Common causes of Bloody diarrhea Introduction: This information shows the various causes of Bloody diarrhea, and how common these diseases or conditions are in the general population. This is not a direct indication as to how commonly these diseases are the actual cause of Bloody diarrhea, but gives a relative idea as to how frequent these diseases are seen overall. # 1 diseases that are "very common". # 5 diseases that are "common". # 3 diseases that are "uncommon". # 8 diseases that are "rare". # 27 diseases without any prevalence information. Top Causes of Bloody diarrhea that are very common The following causes of Bloody diarrhea are diseases or medical conditions that affect more than 10 million people in the USA: * CMV - with AIDS or immune compromise Top Causes of Bloody diarrhea that are common The following causes of Bloody diarrhea are diseases or conditions that affect more than 1 million people in the USA: * Campylobacter food poisoning - bloody diarrhea * Celiac * Colitis * Diverticulitis * Salmonella food poisoning Top Causes of Bloody diarrhea that are uncommon The following causes of Bloody diarrhea are diseases or conditions that affect more than 200,000 people, but less than 1 million people in the USA: * Crohn's disease * Inflammatory bowel disease * Regional enteritis Top Causes of Bloody diarrhea that are very rare The following causes of Bloody diarrhea appear in the population at a rate of substantially less than 200,000 people per year in the USA: * Colorectal cancer * E-coli food poisoning - bloody diarrhea * Escherichia coli O157:H7 - bloody diarrhea * Hemolytic uremic syndrome - bloody diarrhea * Shigella food poisoning * Shigellosis - bloody diarrhea * Vibrio - Bloody diarrhoea * Yersiniosis - bloody diarrhea Top Causes of Bloody diarrhea without any prevalence information The following causes of Bloody diarrhea are ones for which we do not have any prevalence information. * Acute digestive infection * Acute food poisoning * Anal bleeding * Anal fissure - bleeding when passing stool * Balantidiasis - bloody diarrhea * Blood in stool - blood may appear in diarrhea for any of the causes of bloody stool. * Chronic digestive infection * D-plus hemolytic uremic syndrome (D+HUS) - bloody diarrhea * Diarrheagenic Escherichia coli - bloody diarrhea * Ebola - bloody diarrhea * Entamoeba histolytica * Gardner syndrome - bloody diarrhea * Gastroenteritis * Helminthiasis - bloody diarrhea * Ichemic colitis * Proctitis - bloody diarrhea * Pseudomembranous Colitis - Bloody or watery diarrhoea * Rectal bleeding * See also causes of bloody diarrhea and causes of rectal bleeding * Ulcerative colitis - bloody diarrhea * Vibrio mimicus food poisoning - bloody diarrhea * Vibrio vulnificus infection - Bloody diarrhoea * Viral digestive infections - Bloody diarrhoea * Wheat intolerance - Bloody diarrhoea * Whipworm - bloody diarrhea * Wiskott-Aldrich Syndrome - bloody diarrhea * Worm conditions - Bloody diarrhoea TopAll Causes of Bloody diarrhea The full list of all possible causes for Bloody diarrhea described in various sources is as follows: * Acute digestive infection * Acute food poisoning * Anal bleeding * Anal fissure - bleeding when passing stool * Balantidiasis - bloody diarrhea See full list of possible disease causes of Bloody diarrhea Top Drug side effect causes of Bloody diarrhea The following drugs, medications, substances or toxins may possibly cause Bloody diarrhea as a side effect. * Rondomycin * Methacycline * Enoxacin * Enoxin * Austramycin V The following medical conditions are some of the possible causes of Bloody diarrhea. There are likely to be other possible causes, so ask your doctor about your symptoms. * Some possible causes of bloody diarrhea include: o Gastroenteritis o Regional enteritis o Colitis o Rectal bleeding o Anal bleeding o Blood in stool - blood may appear in diarrhea for any of the causes of bloody stool. o Acute digestive infection o Chronic digestive infection (see Digestive symptoms) o Acute food poisoning o Campylobacter food poisoning o Salmonella food poisoning o Shigella food poisoning o E-coli food poisoning o Entamoeba histolytica o Inflammatory bowel disease o Ulcerative colitis o Crohn's disease o Celiac o Ichemic colitis o Diverticulitis o Colorectal cancer o CMV - with AIDS or immune compromise Shigellosis Frequently Asked Questions * What is shigellosis? * What sort of germ is Shigella? * How can Shigella infections be diagnosed? * How can Shigella infections be treated? * Are there long-term consequences to a Shigella infection? * How do people catch Shigella? * What can a person do to prevent this illness? * How common is shigellosis? * What else can be done to prevent shigellosis? * What is the government doing about shigellosis? * How can I learn more about this and other public health problems? * Some tips for preventing the spread of shigellosis What is shigellosis? Shigellosis is an infectious disease caused by a group of bacteria called Shigella. Most who are infected with Shigella develop diarrhea, fever, and stomach cramps starting a day or two after they are exposed to the bacterium. The diarrhea is often bloody. Shigellosis usually resolves in 5 to 7 days. In some persons, especially young children and the elderly, the diarrhea can be so severe that the patient needs to be hospitalized. A severe infection with high fever may also be associated with seizures in children less than 2 years old. Some persons who are infected may have no symptoms at all, but may still pass the Shigella bacteria to others. What sort of germ is Shigella? The Shigella germ is actually a family of bacteria that can cause diarrhea in humans. They are microscopic living creatures that pass from person to person. Shigella were discovered over 100 years ago by a Japanese scientist named Shiga, for whom they are named. There are several different kinds of Shigella bacteria: Shigella sonnei, also known as "Group D" Shigella, accounts for over two-thirds of the shigellosis in the United States. A second type, Shigella flexneri, or "group B" Shigella, accounts for almost all of the rest. Other types of Shigella are rare in this country, though they continue to be important causes of disease in the developing world. One type found in the developing world, Shigella dysenteriae type 1, causes deadly epidemics there. How can Shigella infections be diagnosed? Many different kinds of diseases can cause diarrhea and bloody diarrhea, and the treatment depends on which germ is causing the diarrhea. Determining that Shigella is the cause of the illness depends on laboratory tests that identify Shigella in the stools of an infected person. These tests are sometimes not performed unless the laboratory is instructed specifically to look for the organism. The laboratory can also do special tests to tell which type of Shigella the person has and which antibiotics, if any, would be best to treat it. How can Shigella infections be treated? Shigellosis can usually be treated with antibiotics. The antibiotics commonly used for treatment are ampicillin, trimethoprim/sulfamethoxazole (also known as Bactrim* or Septra*), nalidixic acid, or ciprofloxacin. Appropriate treatment kills the Shigella bacteria that might be present in the patient's stools, and shortens the illness. Unfortunately, some Shigella bacteria have become resistant to antibiotics and using antibiotics to treat shigellosis can actually make the germs more resistant in the future. Persons with mild infections will usually recover quickly without antibiotic treatment. Therefore, when many persons in a community are affected by shigellosis, antibiotics are sometimes used selectively to treat only the more severe cases. Antidiarrheal agents such as loperamide (Imodium*) or diphenoxylate with atropine (Lomotil*) are likely to make the illness worse and should be avoided. Are there long term consequences to a Shigella infection? Persons with diarrhea usually recover completely, although it may be several months before their bowel habits are entirely normal. About 3% of persons who are infected with one type of Shigella, Shigella flexneri, will later develop pains in their joints, irritation of the eyes, and painful urination. This is called Reiter's syndrome. It can last for months or years, and can lead to chronic arthritis which is difficult to treat. Reiter's syndrome is caused by a reaction to Shigella infection that happens only in people who are genetically predisposed to it. Once someone has had shigellosis, they are not likely to get infected with that specific type again for at least several years. However, they can still get infected with other types of Shigella. How do people catch Shigella? The Shigella bacteria pass from one infected person to the next. Shigella are present in the diarrheal stools of infected persons while they are sick and for a week or two afterwards. Most Shigella infections are the result of the bacterium passing from stools or soiled fingers of one person to the mouth of another person. This happens when basic hygiene and handwashing habits are inadequate. It is particularly likely to occur among toddlers who are not fully toilet-trained. Family members and playmates of such children are at high risk of becoming infected. Shigella infections may be acquired from eating contaminated food. Contaminated food may look and smell normal. Food may become contaminated by infected food handlers who forget to wash their hands with soap after using the bathroom. Vegetables can become contaminated if they are harvested from a field with sewage in it. Flies can breed in infected feces and then contaminate food. Shigella infections can also be acquired by drinking or swimming in contaminated water. Water may become contaminated if sewage runs into it, or if someone with shigellosis swims in it. What can a person do to prevent this illness? There is no vaccine to prevent shigellosis. However, the spread of Shigella from an infected person to other persons can be stopped by frequent and careful handwashing with soap. Frequent and careful handwashing is important among all age groups. Frequent, supervised handwashing of all children should be followed in day care centers and in homes with children who are not completely toilet-trained (including children in diapers). When possible, young children with a Shigella infection who are still in diapers should not be in contact with uninfected children. People who have shigellosis should not prepare food or pour water for others until they have been shown to no longer be carrying the Shigella bacterium. If a child in diapers has shigellosis, everyone who changes the child's diapers should be sure the diapers are disposed of properly in a closed-lid garbage can, and should wash his or her hands carefully with soap and warm water immediately after changing the diapers. After use, the diaper changing area should be wiped down with a disinfectant such as household bleach, Lysol* or bactericidal wipes. Basic food safety precautions and regular drinking water treatment prevents shigellosis. At swimming beaches, having enough bathrooms near the swimming area helps keep the water from becoming contaminated. Simple precautions taken while traveling to the developing world can prevent getting shigellosis. Drink only treated or boiled water, and eat only cooked hot foods or fruits you peel yourself. The same precautions prevent traveler's diarrhea in general. How common is shigellosis? Every year, about 18,000 cases of shigellosis are reported in the United States. Because many milder cases are not diagnosed or reported, the actual number of infections may be twenty times greater. Shigellosis is particularly common and causes recurrent problems in settings where hygiene is poor and can sometimes sweep through entire communities. Shigellosis is more common in summer than winter. Children, especially toddlers aged 2 to 4, are the most likely to get shigellosis. Many cases are related to the spread of illness in child-care settings, and many more are the result of the spread of the illness in families with small children. In the developing world, shigellosis is far more common and is present in most communities most of the time. What else can be done to prevent shigellosis? It is important for the public health department to know about cases of shigellosis. It is important for clinical laboratories to send isolates of Shigella to the City, County or State Public Health Laboratory so the specific type can be determined and compared to other Shigella. If many cases occur at the same time, it may mean that a restaurant, food or water supply has a problem which needs correction by the public health department. If a number of cases occur in a day-care center, the public health department may need to coordinate efforts to improve handwashing among the staff, children, and their families. When a community-wide outbreak occurs, a community-wide approach to promote handwashing and basic hygiene among children can stop the outbreak. Improvements in hygiene for vegetables and fruit picking and packing may prevent shigellosis caused by contaminated produce. Some prevention steps occur everyday, without you thinking about it. Making municipal water supplies safe and treating sewage are highly effective prevention measures that have been in place for many years. What is the government doing about shigellosis? The Centers for Disease Control and Prevention (CDC) monitors the frequency of Shigella infections in the country, and assists local and State health departments to investigate outbreaks, determine means of transmission and devise control measures. CDC also conducts research to better understand how to identify and treat shigellosis. The Food and Drug Administration inspects imported foods, and promotes better food preparation techniques in restaurants and food processing plants. The Environmental Protection Agency regulates and monitors the safety of our drinking water supplies. The government has also maintained active research into the development of a Shigella vaccine. How can I learn more about this and other public health problems? You can discuss any medical concerns you may have with your doctor or other heath care provider. Your local city or county health department can provide more information about this and other public health problems that are occurring in your area. General information about the public health of the nation is published every week in the "Morbidity and Mortality Weekly Report", by the CDC in Atlanta, GA. Epidemiologists in your local and State Health Departments are tracking a number of important public health problems, investigating special problems that arise, and helping to prevent them form occurring in the first place, or from spreading if they do occur. Some tips for preventing the spread of shigellosis: * wash hands with soap carefully and frequently, especially after going to the bathroom, after changing diapers, and before preparing foods or beverages * dispose of soiled diapers properly * disinfect diaper changing areas after using them * keep children with diarrhea out of child care settings * supervise handwashing of toddlers and small children after they use the toilet * persons with diarrheal illness should not prepare food for others * if you are traveling to the developing world, "boil it, cook it, peel it, or forget it" * avoid drinking pool water (See more information about this.) ============ Shigellosis Clinical Features Watery or bloody diarrhea, abdominal pain, fever, and malaise. Etiologic Agent Four species of Shigella: boydii, dysenteriae, flexneri, and sonnei. Incidence Approximately 14,000 laboratory confirmed cases of shigellosis and an estimated 448,240 total cases (mostly due to S. sonnei) occur in the United States each year. In the developing world, S.flexneri predominates. Epidemics of S. dysenteriae type 1 have occurred in Africa and Central America with case fatality rates of 5-15%. Sequelae Reiter's syndrome is a late complication of S. flexneri infection, especially in persons with the genetic marker HLA-B27. Hemolytic-uremic syndrome can occur after S. dysenteriae type 1 infection. Convulsions may occur in children; the mechanism may be related to a rapid rate of temperature elevation or metabolic alterations. Transmission A small inoculum (10 to 200 organisms) is sufficient to cause infection. As a result, spread can easily occur by the fecal-oral route and occurs in areas where hygiene are poor. Epidemics may be foodborne or waterborne. Shigella can also be transmitted by flies. Risk Groups In the United States, groups at increased risk of shigellosis include children in child-care centers, contacts of children in child- care settings, and persons in custodial institutions, where personal hygiene is difficult to maintain; Native Americans; orthodox Jews; international travelers; men who have sex with men; and those in homes with inadequate supplies for handwashing. Surveillance All reported cases are laboratory-confirmed in states or at CDC. Trends Decreasing incidence in cases since 1995; characteristically, S. sonnei causes large periodic outbreaks. Challenges Increasing resistance to available antimicrobial agents among isolates acquired domestically and abroad; absence of effective vaccines; modifying handwashing behavior to control prolonged community-wide outbreaks; identifying targeted prevention measures in high-risk groups (e.g., Native Americans, Orthodox Jews, men who have sex with men). Opportunities A major initiative to strengthen laboratory, epidemiologic, and public health capacity to detect and respond to epidemic S.dysenteriae type 1 in southern Africa could be duplicated in other regions at risk. Partnerships with local health departments and communities may lead to investigations of transmission and new prevention materials. Subtyping of S. sonnei by pulsed field gel electrophoresis can improve outbreak detection and control. ================ Shigellosis Shigellosis, also known as bacillary dysentery, is an acute intestinal infection caused by the bacteria Shigella, a short, nonmotile, gram-negative rod. Shigella can be classified into four groups, all of which may cause shigellosis: group A (S. dysenteriae), which is most common in Central America and causes particularly severe infection and septicemia; group B (S. flexneri); group C (S. boydii); and group D (S. sonnei). Typically, shigellosis causes a high fever (especially in children), acute self-limiting diarrhea with tenesmus (ineffectual straining at stool) and, possibly, electrolyte imbalance and dehydration. It's most common in children ages 1 to 4; however, many adults acquire the illness from children. The prognosis is good. Mild infections usually subside within 10 days; severe infections may persist for 2 to 6 weeks. With prompt treatment, shigellosis is fatal in only 1% of cases, although in severe S. dysenteriae epidemic mortality may reach 8%. Causes and incidence Transmission occurs through the fecal-oral route; by direct contact with contaminated objects; or through ingestion of contaminated food or water. Occasionally, the housefly is a vector. Shigellosis is endemic in North America, Europe, and the tropics. In the United States, about 18,000 cases appear annually, usually in children or in elderly, debilitated, or malnourished people. Shigellosis commonly occurs among confined populations, such as those in mental institutions or day- care centers. Signs and symptoms After an incubation period of 1 to 7 days (3 days is the average), Shigella organisms invade the intestinal mucosa and cause inflammation. In children, shigellosis usually produces high fever, diarrhea with tenesmus, nausea, vomiting, irritability, drowsiness, and abdominal pain and distention. Within a few days, the child's stool may contain pus, mucus, and — from the superficial intestinal ulceration typical of this infection — blood. Without treatment, dehydration and weight loss are rapid and overwhelming. In adults, shigellosis produces sporadic, intense abdominal pain, which may be relieved at first by passing formed stools. Eventually, however, it causes rectal irritability, tenesmus and, in severe infection, headache and prostration. Stools may contain pus, mucus, and blood. Fever may be present. Complications of shigellosis, such as electrolyte imbalance (especially hypokalemia), metabolic acidosis, and shock, aren't common but may be fatal in children and patients who are debilitated. Less common complications include conjunctivitis, iritis, arthritis, rectal prolapse, secondary bacterial infection, acute blood loss from mucosal ulcers, and toxic neuritis. Diagnosis CONFIRMING DIAGNOSIS Fever (in children) and diarrhea with stools containing blood, pus, and mucus point to this diagnosis; microscopic bacteriologic studies and culture help confirm it. Microscopic examination of a fresh stool may reveal mucus, red blood cells, and polymorphonuclear leukocytes; direct immunofluorescence with specific antisera will demonstrate Shigella. Severe infection increases hemagglutinating antibodies. Sigmoidoscopy or proctoscopy may reveal typical superficial ulcerations. Diagnosis must rule out other causes of diarrhea, such as enteropathogenic Escherichia coli infection, malabsorption diseases, and amebic or viral diseases. Treatment Treatment of shigellosis includes enteric precautions, low-residue diet and, most important, replacement of fluids and electrolytes with I.V. infusions of normal saline solution (with electrolytes) in sufficient quantities to maintain a urine output of 40 to 50 ml/hour. Antibiotics are of questionable value but may be used in an attempt to eliminate the pathogen and thereby prevent further spread. Ampicillin, tetracycline, or co-trimoxazole may be useful in severe cases, especially in children with overwhelming fluid and electrolyte loss. Sulfamethoxazole-trimethoprim and ciprofloxacin are also used. Antidiarrheals that slow intestinal motility are contraindicated in shigellosis because they delay fecal excretion of Shigella and prolong fever and diarrhea. An investigational vaccine containing attenuated strains of Shigella appears promising in preventing shigellosis. Special considerations Supportive care can minimize complications and increase patient comfort. ?To prevent dehydration, administer I.V. fluids as ordered. Measure intake and output (including stools) carefully. ?Correct identification of Shigella requires examination and culture of fresh stool specimens. Therefore, hand carry specimens directly to the laboratory. Because shigellosis is suspected, include this information on the laboratory slip. ?Use a disposable hot-water bottle to relieve abdominal discomfort, and schedule care to conserve patient strength. ?To help prevent spread of this disease, maintain enteric precautions until microscopic bacteriologic studies confirm that the stool specimen is negative. If a risk of exposure to the patient's stool exists, put on a gown and gloves before entering the room. Keep the patient's (and your own) nails short to avoid harboring organisms. Change soiled linen promptly and store in an isolation container. ?During shigellosis outbreaks, obtain stool specimens from all potentially infected staff, and instruct those infected to remain away from work until two stool specimens are negative. ?Report cases to the local health department. An estimated 300,000 cases of shigellosis occur annually in the U.S. The number attributable to food is unknown, but given the low infectious dose, it is probably substantial. Summary of Notifiable Diseases, United States, 1997:MMWR 46(54) (Source: FDA Bad Bug Book) ... Every year, about 18,000 cases of shigellosis are reported in the United States. Because many milder cases are not diagnosed or reported, the actual number of infections may be twenty times greater. (Source: excerpt from Shigellosis (General): DBMD) TopPrevalence/Incidence of Shigellosis: Online Medical Books 16 MEDICAL BOOKS ONLINE! Review the full text of medical books online, free, without registration, for more information about the prevalence and/or incidence of Shigellosis. Shigellosis: Causes and incidence (Professional Guide to Diseases (Eighth Edition)) Transmission occurs through the fecal-oral route; by direct contact with contaminated objects; or through ingestion of contaminated food or water. Occasionally, the housefly is a vector. Shigellosis is endemic in North America, Europe, and the tropics. In the United States, about 18,000 cases appear annually, usually in children or in elderly, debilitated, or malnourished people. Shigellosis commonly occurs among confined populations, such as those in mental institutions or day- care centers. Approximately 14,000 laboratory confirmed cases of shigellosis and an estimated 448,240 total cases (mostly due to S. sonnei) occur in the United States each year. In the developing world, S.flexneri predominates. Epidemics of S. dysenteriae type 1 have occurred in Africa and Central America with case fatality rates of 5-15%. (Source: excerpt from Shigellosis: DBMD) TopOutbreaks of Shigellosis: MMWR 48(14):1999 In August 1998, the Minnesota Department of Health reported to CDC two restaurant-associated outbreaks of Shigella sonnei infections. Isolates from both outbreaks had two closely related pulsed-field gel electrophoresis (PFGE) patterns that differed only by a single band. Epidemiologic investigations implicated chopped, uncooked, curly parsley as the common vehicle for these outbreaks. MMWR 45(11):1996 On August 20, 1995, the District 7 Health Department requested the Idaho Department of Health to assist in investigating reports of diarrheal illness among visitors to a resort in Island Park in eastern Idaho; Shigella sonnei had been isolated from stool cultures of some cases. This report summarizes the findings of the investigation, which implicated contaminated drinking water as the cause of the outbreak. MMWR 43(35):1994 During August 29-September 1, 1994, an outbreak of gastrointestinal illness occurred on the cruise ship Viking Serenade (Royal Caribbean Cruises, Ltd.) during its roundtrip voyage from San Pedro, California, to Ensenada, Mexico. A total of 37% of passengers and 4% of the crew who completed a survey questionnaire reported having diarrhea or vomiting during the cruise. One death occurred. Investigation of the mode of transmission is under way. MMWR 41(25):1992 In January 1991, the Lexington-Fayette County (Kentucky) Health Department (LFCHD) received three reports of Shigella sonnei infections from the University of Kentucky microbiology laboratory. The infections occurred in children aged 2-3 years, each of whom attended a different child day care center in Lexington-Fayette County (population:200,000). MMWR 40(25):1991 On March 14, 1991, physicians at a hospital in Guatemala City reported to the Institute of Nutrition of Central America and Panama (INCAP) that a 2-year-old boy living in an orphanage in Guatemala City had been hospitalized with dysentery. Another child from the orphanage had recently died from dysentery. During March 18-21, two other young children from the orphanage were diagnosed with Shigella dysenteriae type 1. On March 21, health officials in Rabinal, in the department of Baja Verapaz, reported more than 100 cases of dysentery to the Division of Epidemiology and Disease Control of the Ministry of Health (MOH). MMWR 39(30):1990 From 1986 to 1988*, the reported isolation rate of Shigella in the United States increased from 5.4 to 10.1 isolates per 100,000 persons. In addition to the increase in Shigella isolation rates, many communitywide shigellosis outbreaks that have been difficult to control have been reported. This report describes four community outbreaks of shigellosis during 1986-1989 in which innovative public health control measures were used. MMWR 37(31):1988 From January 1 to August 1, 1988, 17 cases of diarrheal disease caused by Shigella dysenteriae type 1 (Shiga bacillus) were reported to CDC. Three cases were reported to CDC during the same period in 1987. Fifteen of the patients with shigellosis had visited Cancun, Mexico, andd two had visited other areas in Mexico in the weeks before or during onset of their illness. The patients had no common exposures in hotels or restaurants. An epidemiologic and laboratory investigation is under way in Mexico. In 1988, numerous individuals contracted shigellosis from food consumed aboard Northwest Airlines flights; food on these flights had been prepared in one central commisary. No specific food item was implicated, but various sandwiches were suspected. MMWR 36(38):1987 In early July 1987, an outbreak of multiply resistant Shigella sonnei gastroenteritis occurred among persons who attended the annual Rainbow Family gathering in North Carolina. Since that time, four clusters of gastroenteritis due to multiply resistant S. sonnei have been reported among persons who had no apparent contact with gathering attendees. Basic hygiene and sanitary precautions remain the cornerstones of control measures for shigellosis outbreaks, including those due to multiply resistant strains. Vigorous emphasis on handwashing with soap after defecation and before eating has been shown to reduce secondary transmission of shigellosis. MMWR 36(27):1987 CDC has received reports that shigellosis outbreaks have occurred in several states, affecting related religious communities. Dates of onset range from November 1986 through June 1987. The largest outbreak was in New York City, and outbreaks in other states began soon after the Passover holiday in April, when many persons visited relatives in New York. Epidemiologic data are incomplete, but in some of these outbreaks new cases continue to occur. MMWR 35(48):1986 Between October 10 and November 6, 1985, 15 children at a day-care center in Diboll, Texas, developed a diarrheal illness. Shigella sonnei was isolated from 10 ill children and from two of 19 asymptomatic children who were cultured on November 7. All isolates were colicin type 9, resistant to ampicillin, carbenicillin, streptomycin, cephalothin, and trimethoprim/sulfamethoxazole (TMP/SMX), and sensitive to tetracycline, nalidixic acid, chloramphenicol, and gentamicin. The attack rate was highest among the 12- to 22-month-old group. Family members of this group had the highest secondary attack rate. No cases occurred among the 22 staff members. In 1985-1986, several outbreaks of shigellosis occurred on college campuses, usually associated with fresh vegetables from the salad bar. Usually an ill food service worker was shown to be the cause. In 1985, a huge outbreak of foodborne shigellosis occurred in Midland-Odessa, Texas, involving perhaps as many as 5,000 persons. The implicated food was chopped, bagged lettuce, prepared in a central location for a Mexican restaurant chain. FDA research subsequently showed that S. sonnei, the isolate from the lettuce, could survive in chopped lettuce under refrigeration, and the lettuce remained fresh and appeared to be quite edible. MMWR 34(39):1985 In 1984, 12,790 Shigella isolates from humans were reported to CDC. This is a 14.4% decrease from the 14,946 isolates reported in 1983. The number of isolates continues to be less than the 15,334 reported during the peak year, 1978. MMWR 33(43):1984 In 1983, 14,946 Shigella isolates from humans were reported to CDC. This is a 10.5% increase from the 13,523 isolates reported in 1982. The number of isolates is still less than the 15,334 reported during the peak year, 1978. MMWR 32(34):1983 In 1982, 13,523 Shigella isolations from humans were reported to CDC. This represents a 9.9% decrease from the 15,006 isolations reported in 1981. The number of isolations has continued to decline from the 15,334 reported during the peak year, 1978. MMWR 32(19):1983 An outbreak of severe dysentery caused by Shigella dysenteriae type 2 recently occurred at the U.S. Naval Hospital, Bethesda, Maryland. Epidemiologic investigation implicated the salad bar in the active-duty staff cafeteria as the source of infection. MMWR 31(50):1982 In 1981, 15,006 Shigella isolations from humans were reported to CDC. While this represented a 6% increase over the 14,168 isolates reported in 1980, it remained 2% below the 15,334 reported during the peak year, 1978. **NOTE - Although all Shigella spp. have been implicated in foodborne outbreaks at some time, S. sonnei is clearly the leading cause of shigellosis from food. The other species are more closely associated with contaminated water. One in particular, S. flexneri, is now thought to be in large part sexually transmitted. Morbidity and Mortality Weekly Reports For more information on recent outbreaks see the CDC. (Source: FDA Bad Bug Book) TopIncidence statistics for Shigellosis: The following statistics relate to the incidence of Shigellosis: * 3.70 per 100,000 in Canada 20001 * 2.5 new cases of shigellosis per 100,000 population was notified in Australia 2002 (Yohannes K, Roche P, Blumer C et al. 2004, Australia’s Health 2004, AIHW) * 496 new cases of shigellosis was notified in Australia 2002 (Yohannes K, Roche P, Blumer C et al. 2004, Australia’s Health 2004, AIHW) TopAbout prevalence and incidence statistics: The term 'prevalence' of Shigellosis usually refers to the estimated population of people who are managing Shigellosis at any given time. The term 'incidence' of Shigellosis refers to the annual diagnosis rate, or the number of new cases of Shigellosis diagnosed each year. Hence, these two statistics types can differ: a short-lived disease like flu can have high annual incidence but low prevalence, but a life-long disease like diabetes has a low annual incidence but high prevalence. For more information see about prevalence and incidence statistics. Prognosis of Shigellosis Duration of Shigellosis: Shigellosis usually resolves in 5 to 7 days. (Source: excerpt from Shigellosis (General): DBMD) Deaths from Shigellosis: 10 reported deaths in USA 1999 for shigellosis and amebiasis (NVSR Sep 2001) Estimated mortality rate for Shigellosis from incidence and deaths statistics: * Deaths: 10 (USA annual deaths calculated from this data: 10 reported deaths in USA 1999 for shigellosis and amebiasis (NVSR Sep 2001)) * Incidence: 17,521 (USA annual incidence calculated from this data: 17,521 annual cases of shigellosis notified in USA 1999 (MMWR 1999) * 0.057% (ratio of deaths to incidence). Complications: see complications of Shigellosis TopResearch More About Shigellosis * Introduction: Shigellosis * Deaths: Shigellosis * Symptoms: Shigellosis * Complications: Shigellosis TopAbout prognosis: The 'prognosis' of Shigellosis usually refers to the likely outcome of Shigellosis. The prognosis of Shigellosis may include the duration of Shigellosis, chances of complications of Shigellosis, probable outcomes, prospects for recovery, recovery period for Shigellosis, survival rates, death rates, and other outcome possibilities in the overall prognosis of Shigellosis. Naturally, such forecast issues are by their nature unpredictable. Children and Shigellosis This section discusses the causes of Shigellosis in children, babies, infants, or toddlers. You can also refer to the list of causes of Shigellosis in any age group. Shigellosis in Children: Online Medical Pediatrics Textbooks 16 medical textbooks online! (free access, no registration). Full online access to the full text of medical textbooks covering pediatrics (including child health, babies, infants, older children, preteens, teens, etc.), free of charge and without registration, for published medical textbooks related to the causes of Shigellosis in children. Diarrhea – Acute (In A Page: Pediatric Signs and Symptoms) READ FULL BOOK ONLINE (free access, no registration) ... Acute diarrhea is an abrupt onset of increased fluid content of stool above about 10 mL/kg/day and increased frequency from 4–5 to more than 20 times daily. It is a major problem worldwide because of excessive loss of fluid and electrolytes in... Differential Diagnosis ... Workup and Diagnosis ... Treatment ... READ FULL BOOK ONLINE » (free access, no registration) Diarrhea – Chronic, No Blood or Weight Loss (In A Page: Pediatric Signs and Symptoms) READ FULL BOOK ONLINE (free access, no registration) ... Chronic diarrhea (nonbloody, without weight loss) is defined as increased total daily stool output (greater than 10 g/kg/day), associated with increased stool water content; diarrhea is classified as chronic when it lasts longer than 2 weeks. Per liter, normal stool of infants and children contains approximately... Differential Diagnosis ... Workup and Diagnosis ... Treatment ... READ FULL BOOK ONLINE » (free access, no registration) Diarrhea – Chronic, with Weight Loss (In A Page: Pediatric Signs and Symptoms) READ FULL BOOK ONLINE (free access, no registration) ... Diarrhea is considered chronic when it last longer than 14 days. Weight loss with diarrhea should always be concerning and deserves thorough investigation. Collectively the malabsorption syndromes are the most common etiologic factors. Differential Diagnosis ... Workup and Diagnosis ... Treatment ... READ FULL BOOK ONLINE » (free access, no registration) Diarrhea (The Diagnostic Approach to Symptoms and Signs in Pediatrics) READ FULL BOOK ONLINE (free access, no registration) ... Definedas stools that are more fluid and frequent than normal. Can be acute or chronic (>2–3wks in duration). Acute diarrhea is discussed in first section ofthis chapter, and chronic diarrhea is discussed in second section. Principle Causes of Acute Diarrhea Infection ... Clinical Features and Diagnosis: Acute Diarrhea ... Diagnostic Approach: Acute Diarrhea ... Principle Causes of Chronic Diarrhea ... Clinical Features and Diagnosis: Chronic Diarrhea ... Diagnostic Approach: Chronic Diarrhea ... References ... READ FULL BOOK ONLINE » (free access, no registration) Copyright notice for book excerpts: Copyright © 2007 Lippincott Williams & Wilkins. All rights reserved. TopChildren and Shigellosis: Online Medical Books 16 MEDICAL BOOKS ONLINE! Review the full text of medical pediatrics books online, free, without registration, for more information about causes of Shigellosis in children (including babies, infants, toddlers, and older children). Diarrhea: Pediatric pointers (Professional Guide to Signs & Symptoms (Fifth Edition)) Diarrhea in children commonly results from infection, although chronic diarrhea may result from malabsorption syndrome, an anatomic defect, or allergies. Because dehydration and electrolyte imbalance occur rapidly in children, diarrhea can be life-threatening. Diligently monitor all episodes of diarrhea, and replace lost fluids immediately. READ FULL BOOK TEXT ONLINE » Diarrhea: Pediatric pointers (Alarming Signs and Symptoms: Lippincott Manual of Nursing Practice Series) Diarrhea in children commonly results from infection, although chronic diarrhea may result from malabsorption syndrome, an anatomic defect, or allergies. Because dehydration and electrolyte imbalance occur rapidly in children, diarrhea can be life-threatening. Diligently monitor all episodes of diarrhea, and immediately replace lost fluids. READ FULL BOOK TEXT ONLINE » Diarrhea: Pediatric pointers (Signs & Symptoms: A 2-in-1 Reference for Nurses) Diarrhea in children commonly results from infection, although chronic diarrhea may result from malabsorption syndrome, an anatomic defect, or allergies. Because dehydration and electrolyte imbalance occur rapidly in children, diarrhea can be life-threatening. Diligently monitor all episodes of diarrhea, and immediately replace lost fluids. READ FULL BOOK TEXT ONLINE » Copyright notice for book excerpts: Copyright © 2007 Lippincott Williams & Wilkins. All rights reserved. Misdiagnosis of Shigellosis Contents *1 *2 *3 1. Alternative Diagnoses List 2. Possible Misdiagnoses 3. Misdiagnosis Center 4. Introduction: Shigellosis 5. Symptoms: Shigellosis TopAlternative diagnoses list for Shigellosis: For a diagnosis of Shigellosis, the following list of conditions have been mentioned in sources as possible alternative diagnoses to consider during the diagnostic process for Shigellosis: * Salmonella * Campylobacter * E. coli * Amebic dysentery * Inflammatory bowel disease * Viral gastroenteritis * Food poisoning TopDiseases for which Shigellosis may be an alternative diagnosis The other diseases for which Shigellosis is listed as a possible alternative diagnosis in their lists include: * Traveler's diarrhea * Ulcerative colitis TopGeneral Misdiagnosis Articles Read these general articles with an overview of misdiagnosis issues. * Misdiagnosis Overview * How Common is Misdiagnosis? * Over-Diagnosed Diseases * Under-Diagnosed Diseases * Types of Misdiagnosis * Wrong Type Misdiagnosis * Why Does Misdiagnosis Occur? * Difficult Diseases to Diagnose * More premium medical articles ... TopAbout misdiagnosis: When checking for a misdiagnosis of Shigellosis or confirming a diagnosis of Shigellosis, it is useful to consider what other medical conditions might be possible misdiagnoses or other alternative conditions relevant to diagnosis. These alternate diagnoses of Shigellosis may already have been considered by your doctor or may need to be considered as possible alternative diagnoses or candidates for misdiagnosis of Shigellosis. For a general overview of misdiagnosis issues for all diseases, see Overview of Misdiagnosis. Treatments for Shigellosis Contents *1 *2 *3 1. Discussion of treatments for Shigellosis 2. Buy Products Related to Treatments for Shigellosis 3. Find a Therapist or Health Professional 4. Introduction: Shigellosis TopTreatments of Shigellosis: Online Medical Books 16 MEDICAL BOOKS ONLINE! Review the full text of medical books online, free, without registration, for more information about the treatments of Shigellosis. Diarrhea - Acute: Treatment (In a Page: Signs and Symptoms) * Treatment is generally supportive * Fluid resuscitation (oral, if possible, or IV) * Antimotility agents: Opiates (e.g., loperamide) and parasympathetic inhibitors (e.g., diphenoxylate plus atropine); former concerns that these agents may slow the clearance of pathogens have been disproved * Antibiotic therapy is reserved for severe disease –Most authorities recommend empiric treatment with a fluoroquinolone or trimethoprin-sulfamethoxasole in patients with severe or bloody diarrhea, fever, or fecal leukocytes –If Giardia, C. difficile, or E. histolytica is suspected, treat empirically with metronidazole –Antibiotic therapy increases the risk of hemolytic-uremic syndrome in children with E. coli O157:H7 –There is no good evidence that antibiotics prolong the carrier state in Salmonella infections * Advise patient to hydrate with glucose-containing, caffeine-free beverages, and to avoid lactose, sorbitol-containing gum, and raw fruit until symptoms subside READ FULL BOOK TEXT ONLINE » Diarrhea - Chronic: Treatment (In a Page: Signs and Symptoms) * Fluid resuscitation: Oral, if possible, or IV (e.g., normal saline or lactated Ringer's) * Nonspecific antidiarrheal agents (e.g., loperamide, codeine, tincture of opium) and fiber supplementation may be attempted initially * Diabetic neuropathy: Control blood sugar, metoclopramide may be used * Irritable bowel syndrome: High-fiber diet, anticholinergics * Inflammatory bowel disease is treated with steroids for acute exacerbations and daily prophylactic therapy with 5-aminosalicyclic agents –Bowel resection may be necessary * Lactose intolerance: Lactose-free diet * Diseases of malabsorption: Gluten-free diet, long-term antibiotics * Intestinal neoplasm: Consultation with gastroenterology, oncology, and/or surgery > READ FULL BOOK TEXT ONLINE » Diarrhea – Acute: Treatment (In A Page: Pediatric Signs and Symptoms) * Mainstay of treatment is rehydration to correct fluid and electrolyte deficits –Oral route is best in mildly to moderately dehydrated children who can tolerate PO fluid –IV fluids: Useful in severe to moderate dehydration –Estimate fluid deficit using % of weight loss, and add this to maintenance requirement and ongoing losses – Correct over 24–48 hours o Antibiotics –Not necessary in most cases, can precipitate HUS –Indicated for V. cholerae, Shigella, and G. lamblia –Indicated in selected circumstances: Salmonella in very young infant, if febrile, or positive blood culture –Metronidazole for C. difficile (if antibiotic elimination doesn’t help) * Refeeding: No benefit to withholding milk, incidence of lactose intolerance overstated * Probiotics: Lactobacillus rhamnosus for rotavirus READ FULL BOOK TEXT ONLINE » Diarrhea – Chronic, No Blood or Weight Loss: Treatment (In A Page: Pediatric Signs and Symptoms) * Treatment is directed at cause * Chronic nonspecific diarrhea –Restriction of fluid intake to <90 mL/kg/day –Reduction of fruit juices (<8 ounces/day) –Elimination of sorbitol-containing juices * Carbohydrate malabsorption –Trial elimination or reduction of offending sugar –Lactase (Lactaid) for lactose intolerance –Sucrase (Sucraid) for sucrase-isomaltase deficiency o Small intestine bacterial overgrowth –Antibiotic therapy with metronidazole alone or in combination with ampicillin or Bactrim –Surgery for partial small bowel obstruction * Low-fat diet: Increase fat intake to approximately 40% of total daily calorie intake * Irritable bowel syndrome –Anticholinergic therapy or antidepressants * Acrodermatitis enteropathica: Zinc supplements >>>>> >> READ FULL BOOK TEXT ONLINE » Diarrhea – Chronic, with Weight Loss: Treatment (In A Page: Pediatric Signs and Symptoms) * Correct malnourished states * IBD: Anti-inflammatories (e.g., steroids, 6MP, 5ASA) * CD: Lifelong gluten-free diet * CF: Pancreatic enzyme and nutritional supplements including fat-soluble vitamins (ADEK) * Allergy: Food antigen avoidance * Sucrase-isomaltase deficiency: “Sucraid” enzyme * Neural crest tumors: Surgical resections * VIPoma: Somatostatin * Gastrinoma: Proton pump inhibitors * Whipple disease: Trimethoprim-sulfamethoxazole * Abetalipoprotenemia: No specific treatment –Supplements of fat-soluble vitamins and MCT oil * Acrodermatitis enteropathica: Zinc supplements * Giardiasis: Metronidazole or nitazoxamide * Hyperalimentation: Parenteral nutrition may be needed for familial enteropathies READ FULL BOOK TEXT ONLINE » Shigellosis: Treatment (Professional Guide to Diseases (Eighth Edition)) Treatment of shigellosis includes enteric precautions, low-residue diet and, most important, replacement of fluids and electrolytes with I.V. infusions of normal saline solution (with electrolytes) in sufficient quantities to maintain a urine output of 40 to 50 ml/hour. Antibiotics are of questionable value but may be used in an attempt to eliminate the pathogen and thereby prevent further spread. Ampicillin, tetracycline, or co-trimoxazole may be useful in severe cases, especially in children with overwhelming fluid and electrolyte loss. Sulfamethoxazole-trimethoprim and ciprofloxacin are also used. Antidiarrheals that slow intestinal motility are contraindicated in shigellosis because they delay fecal excretion of Shigella and prolong fever and diarrhea. An investigational vaccine containing attenuated strains of Shigella appears promising in preventing shigellosis. READ FULL BOOK TEXT ONLINE » Poisoning: Treatment (Tx) (Professional Guide to Diseases (Eighth Edition)) Depending on poison: airway management, CPR, poison antidote, patient placed on left side, supportive care (I.V. fluid replacement, oxygen therapy, seizure precautions) READ FULL BOOK TEXT ONLINE » Diarrhea: Emergency interventions (Professional Guide to Signs & Symptoms (Fifth Edition)) If the patient’s diarrhea is profuse, check for signs of shock—tachycardia, hypotension, and cool, pale, clammy skin. If you detect these signs, place the patient in the supine position and elevate his legs 20 degrees. Insert an I.V. line for fluid replacement. Monitor the patient for electrolyte imbalances, and look for an irregular pulse, muscle weakness, anorexia, and nausea and vomiting. Keep emergency resuscitation equipment handy. READ FULL BOOK TEXT ONLINE » Diarrhea: Nursing considerations (Alarming Signs and Symptoms: Lippincott Manual of Nursing Practice Series) Administer an analgesic for pain and an opioid to decrease intestinal motility, unless the patient has a possible or confirmed stool infection. Ensure the patient’s privacy during defecation, and empty bedpans promptly. Clean the perineum thoroughly, and apply ointment to prevent skin breakdown. ALERT: Excessive diarrhea may cause skin breakdown and excoriation. To decrease excoriation and facilitate drainage measurement, insert a rectal tube or large indwelling catheter. Help the patient maintain adequate hydration, administering I.V. fluid replacements. Measure liquid stools, and weigh the patient daily. Monitor electrolyte levels and hematocrit. Quantify the amount of liquid stool and carefully observe intake and output. TopPatient teaching Explain the purpose of diagnostic tests to the patient. These tests may include blood studies, stool cultures, X-rays, and endoscopy. Advise the patient to avoid spicy or high-fiber foods (such as fruits), caffeine, high-fat foods, and milk. Suggest smaller, more frequent meals if he has had GI surgery or disease. If appropriate, teach the patient stress-reducing exercises, such as guided imagery and deep-breathing techniques, or recommend counseling. Stress the need for medical follow-up to patients with inflammatory bowel disease (particularly ulcerative colitis), who have an increased risk of developing colon cancer. READ FULL BOOK TEXT ONLINE » Diarrhea: Emergency Actions (Signs & Symptoms: A 2-in-1 Reference for Nurses) If the patient’s diarrhea is profuse, check for signs of shock, including tachycardia, hypotension, and cool, pale, clammy skin. If you detect these signs, place the patient in the supine position and elevate his legs 20 degrees. Insert an I.V. line for fluid replacement. Monitor patient for electrolyte imbalances, and look for an irregular pulse, muscle weakness, anorexia, and nausea and vomiting. Keep emergency resuscitation equipment handy. READ FULL BOOK TEXT ONLINE » Diarrhea: Nursing considerations (Nursing: Interpreting Signs and Symptoms) ? Administer an analgesic for pain and an opiate to decrease intestinal motility, unless the patient has a possible or confirmed stool infection. ? Ensure the patient's privacy during defecation, and empty bedpans promptly. ? Clean the perineum thoroughly, and apply ointment to prevent skin breakdown. ? Note the amount and characteristics of the patient's stool. ? Monitor intake and output. ? Obtain serum samples for electrolytes and treat imbalances. ? Provide fluid replacement orally or I.V., as appropriate. TopPatient teaching ? Stress the need for medical follow-up to patients with inflammatory bowel disease (particularly ulcerative colitis) who have an increased risk of developing colon cancer. ? Emphasize the importance of maintaining adequate hydration. ? Explain food or fluids that should be avoided. ? Discuss stress reduction techniques. ? Explain the diagnosis and treatment plan. READ FULL BOOK TEXT ONLINE » TopMedications used to treat Shigellosis: Note:You must always seek professional medical advice about any treatment or change in treatment plans. Some of the different medications used in the treatment of Shigellosis include: * Cephalosporin Antibiotic Drugs * Cefaclor * Ceclor * Cefadroxil * Duricef * Ultracef * Cefixime * Suprax * Cefprozil * Cefzil * Ceftriaxone * Rocephin * Cefuroxime * Ceftin * Kefurox * Zinaxef * Cephalexin * Apo-Cephalex * Cefanex * Ceporex * Keflet * Keflex * Keftab * Novo-Lexin * Nu-Cephalex * Loracarbef * Lorabid Unlabelled alternative drug treatments include: * Rocephin * Amcel * Benaxona * Cefaxona * Ceftrex * Tacex * Terbac * Triaken * Ceftriaxone TopDiscussion of treatments for Shigellosis: Shigellosis can usually be treated with antibiotics. The antibiotics commonly used for treatment are ampicillin, trimethoprim/sulfamethoxazole (also known as Bactrim* or Septra*), nalidixic acid, or ciprofloxacin. Appropriate treatment kills the Shigella bacteria that might be present in the patient's stools, and shortens the illness. Unfortunately, some Shigella bacteria have become resistant to antibiotics and using antibiotics to treat shigellosis can actually make the germs more resistant in the future. Persons with mild infections will usually recover quickly without antibiotic treatment. Therefore, when many persons in a community are affected by shigellosis, antibiotics are sometimes used selectively to treat only the more severe cases. Antidiarrheal agents such as loperamide (Imodium*) or diphenoxylate with atropine (Lomotil*) are likely to make the illness worse and should be avoided. (Source: excerpt from Shigellosis (General): DBMD) DIARRHEA, ACUTE TopAsk the following questions: 1. Is there blood in the stool? From the algorithm, blood in the stool should indicate that there is Salmonella , Shigella , Campylobacter jejuni , ulcerative colitis, and amebic dysentery. Without blood in the stool, it is more likely that the acute diarrhea is due to a staphylococcal toxin, giardiasis, traveler's diarrhea, a virus, or contaminated food. 2. Is there a fever? Fever, especially with an elevated white count and blood in the stool, would suggest Salmonella , Shigella , Campylobacter jejuni , or ulcerative colitis in its acute stage. The absence of fever would suggest amebic dysentery or giardiasis, although there may be fever in amebic dysentery in the severe cases. Even traveler's diarrhea and toxic staphylococcal gastroenteritis do not usually give more than a low-grade temperature at best. Pseudomembranous colitis may result in a significant elevation of the temperature once the patient becomes severely dehydrated. 3. Is there severe vomiting? Severe vomiting is seen in toxic staphylococcal gastroenteritis! This follows 2 to 4 hr after eating food poisoned with the toxin. Traveler's diarrhea and viral gastroenteritis may also cause severe vomiting, as may food that is contaminated. On the other hand, there is little or no vomiting in giardiasis and pseudomembranous colitis. 4. Did several members of the family experience acute diarrhea also? This is a key question because it indicates whether there is a possibility of toxic staphylococcal gastroenteritis or the possibility of a contagious condition such as infection with Salmonella , Shigella , or Campylobacter . If only one member of the family was suffering from diarrhea and everyone is eating the same food, then it is less likely to be a contagious condition, and one must consider ulcerative colitis, pseudomembranous colitis, and conditions listed under chronic diarrhea. 5. Was there recent foreign travel? Recent foreign travel would suggest the possibility of traveler's diarrhea, cholera, shigellosis, salmonellosis, and giardiasis. 6. Is there neurologic symptomatology? This should point one in the direction of botulism, and generally a little epidemiologic research will disclose that other people in the community have been suffering from the same condition. TopDIAGNOSTIC WORKUP The first thing to do is a stool for occult blood. This will help distinguish those patients who are having obvious infectious disease of the large intestine or maybe even the small intestine. It will also make one suspicious of ulcerative colitis. All patients need a stool culture and stool for ova and parasites. A stool for Giardia antigen can also be done. Serologic studies will not be of much help in the acute condition, but they may help later on in cases of salmonellosis and amebiasis. The clinician himself should do a methylene blue smear for leukocytes and examine a wet saline preparation of the stool. If there is a history of antibiotic uses, a stool should be tested for Clostridium difficile toxin B. Leukocytes on a smear suggest bacterial cause and a culture should be done. The laboratory should be alerted if Campylobacter or Yersinia are suspected because special culture media are needed. If the diarrhea persists or if there is blood, sigmoidoscopy or colonoscopy should be performed. It is always important to examine the rectum for hemorrhoids and anal fissures that may be causing the positive stool for occult blood. When the diarrhea persists and becomes chronic, the diagnostic workup should include the studies that are listed under chronic diarrhea. Amebiasis Amebiasis, also known as amebic dysentery, is an acute or chronic protozoal infection caused by Entamoeba histolytica. This infection produces varying degrees of illness, from no symptoms at all or mild diarrhea to fulminant dysentery. Extraintestinal amebiasis can induce hepatic abscess and infections of the lungs, pleural cavity, pericardium, peritoneum and, rarely, the brain. The prognosis is generally good, although complications — such as ameboma, intestinal stricture, hemorrhage or perforation, intussusception, or abscess — increase mortality. Brain abscess, a rare complication, is usually fatal. TopCauses and incidence E. histolytica exists in two forms: a cyst (which can survive outside the body) and a trophozoite (which can't survive outside the body). Transmission occurs through ingesting feces-contaminated food or water. The ingested cysts pass through the intestine, where digestive secretions break down the cysts and liberate the motile trophozoites within. The trophozoites multiply and either invade and ulcerate the mucosa of the large intestine or simply feed on intestinal bacteria. As the trophozoites are carried slowly toward the rectum, they are encysted and then excreted in feces. Humans are the principal reservoir of infection. Amebiasis occurs worldwide but is most common in the tropics, subtropics, and other areas with poor sanitation and health practices. Incidence in the United States averages between 1% and 3% but may be higher among homosexuals and institutionalized people, in whom fecal-oral contamination is common. TopSigns and symptoms The clinical effects of amebiasis vary with the severity of the infestation. Acute amebic dysentery causes a sudden high temperature of 104° to 105° F (40° to 40.6° C) accompanied by chills and abdominal cramping; profuse, bloody, mucoid diarrhea with tenesmus; and diffuse abdominal tenderness due to extensive rectosigmoid ulcers. Chronic amebic dysentery produces intermittent diarrhea that lasts for 1 to 4 weeks and recurs several times a year. Such diarrhea produces 4 to 8 (or, in severe diarrhea, up to 18) foul-smelling mucus- and blood-tinged stools daily in a patient with a mild fever, vague abdominal cramps, possible weight loss, tenderness over the cecum and ascending colon and, occasionally, hepatomegaly. Amebic granuloma (ameboma), commonly mistaken for cancer, can be a complication of the chronic infection. Amebic granuloma produces blood and mucus in the stool and, when granulomatous tissue covers the entire circumference of the bowel, causes partial or complete obstruction. Parasitic and bacterial invasion of the appendix may produce typical signs of subacute appendicitis (abdominal pain and tenderness). Occasionally, E. histolytica perforates the intestinal wall and spreads to the liver. When it perforates the liver and diaphragm, it spreads to the lungs, pleural cavity, peritoneum and, rarely, the brain. TopDiagnosis CONFIRMING DIAGNOSIS Isolating E. histolytica (cysts and trophozoites) in fresh feces or aspirates from abscesses, ulcers, or tissue confirms acute amebic dysentery. Diagnosis must distinguish between cancer and ameboma with X-rays, sigmoidoscopy, stool examination for amebae, and cecum palpation. In patients with amebiasis, exploratory surgery is hazardous; it can lead to peritonitis, perforation, and pericecal abscess. Other laboratory tests that support the diagnosis of amebiasis include: ?indirect hemagglutination test — positive with current or previous infection ?complement fixation — usually positive only during active disease ?barium studies — rule out nonamebic causes of diarrhea, such as polyps and cancer ?sigmoidoscopy — detects rectosigmoid ulceration; a biopsy may be helpful. Patients with amebiasis shouldn’t have preparatory enemas because these may remove exudates and destroy the trophozoites, thus interfering with test results. TopTreatment Drugs used to treat amebic dysentery include metronidazole, an amebicide at intestinal and extraintestinal sites; emetine hydrochloride, also an amebicide at intestinal and extraintestinal sites, including the liver and lungs; iodoquinol (diiodohydroxyquin), an effective amebicide for asymptomatic carriers; chloroquine, for liver abscesses, not intestinal infections; and tetracycline (in combination with emetine hydrochloride, metronidazole, or paromomycin), which supports the antiamebic effect by destroying intestinal bacteria on which the amebae normally feed. When nausea and vomiting are present, I.V. therapy may be necessary until medications are tolerated by mouth. TopSpecial considerations ?Tell patients with amebiasis to avoid drinking alcohol when taking metronidazole. The combination may cause nausea, vomiting, and headache. ?Antidiarrheals aren’t prescribed and can make the condition worse. ?After treatment, stools should be re-checked to make sure the infection has been cleared. Copyright Details: Professional Guide to Diseases (Eighth Edition), Copyright © 2005 Lippincott Williams & Wilkins. REASONS FOR COLONOSCOPY — The most common reasons for colonoscopy are to evaluate the following: * As a screening exam for colon cancer in anyone over age 50 * Blood in the stool or rectal bleeding * Dark/black stools * Persistent diarrhea * Iron deficiency anemia (a decrease in blood count due to loss of iron) * Significant, unexplained weight loss, accompanied by gastrointestinal symptoms * A family history of colon cancer * To follow up an abnormal barium enema * A history of previous colon polyps or colon cancer * Surveillance in people with ulcerative colitis * For the medical management of chronic inflammatory bowel disease * Chronic, unexplained abdominal pain.