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Board Review QuiZ MAY

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Board Review QuiZ –MAY
1) Question 58 2010 answer A
Children who are born relatively large but are destined to have short stature as adults because they
come from short families (familial short stature) generally show a shift in growth percentiles so that
by the time they are 2 years of age, they are growing at a steady rate and their height percentile is
appropriate for their family. They mature at a normal time and achieve short normal adult stature
after reaching full maturation, as in growth chart A. Some affected children have idiopathic short
stature and some may have a known single gene mutation leading to short stature.

Growth charts B, C, and D show the progress of children who have growth attenuation or arrest
occurring or persisting past the second year. Such children likely have serious underlying illnesses
interfering with linear growth. An examination of weight for age might be helpful in assessing the
cause of the growth attenuation. For example, a child who has celiac disease would be underweight
and often experience weight loss before slowing in growth, while a child who has hypothyroidism
would have a normal weight or be overweight for age, but have marked growth attenuation.

Growth chart E shows a continuation of growth with a growth spurt after other boys have reached
adult height. A period of slowdown or attenuation in growth rate is documented just before the
pubertal growth spurt, which may be relatively prolonged if puberty is late. This pattern is seen in
delayed adolescence, and it can be associated with relative short stature during childhood and a
normal adult height.

American Board of Pediatrics Content Specifications:


       Know how to distinguish between familial short stature and other conditions
       Recognize the signs of familial short stature


2) question 90 2010 answer E
Children who have constitutional delay commonly have a strong family history of such delay, and in
some cases, genes associated with hypothalamic hypogonadism have been identified in affected
families. However, in most recent studies, no genes to explain constitutional delay have been found,
although the pattern of growth is clearly heritable and as common in females as in males.
Therefore, a boy whose mother experienced late menarche might be expected to have delayed
puberty. Such a boy might have continued growth at a prepubertal growth rate or even rather
marked growth attenuation (slowed growth rate before puberty) at the age when other boys are
entering puberty, followed by a catch-up in height after late puberty, with normal linear growth
sometimes continuing into the third decade of life. When there is growth attenuation, it is important
to rule out other reasons for the slowing, although in most cases, the boy simply is following a
familial pattern.

Absence of olfaction is a component of Kallmann syndrome, one of the hypothalamic hypogonadism
disorders. However, this is not a common finding in children who have delayed puberty. The finding
of pubic hair does not permit the identification of gonadal pubertal stage because premature adrenal
puberty (adrenarche or pubarche) is identified clinically by the presence of pubic hair without
testicular enlargement. Testicular size is a better indicator of true puberty.

If the boy described in the vignette were small for gestational age at birth, this might contribute to
his short stature as a young teenager. Children who are born small for gestational age and do not
catch up to the 10th percentile in height by the time they are 2 years of age have a United States
Food and Drug Administration-approved indication to receive growth hormone. Even if the children
have relatively delayed bone ages and ostensibly good adult height predictions, if adult height is a
concern, growth hormone often is a reasonable treatment because many such children have
pubertal courses that involve limited growth spurts that do not permit them to reach the heights
initially predicted. A short boy whose weight is at the 50th percentile is overweight or obese. Such a
finding could be associated with an underlying endocrine disorder such as hypothyroidism or
Cushing disease, but does not influence a potential diagnosis of delayed puberty.

American Board of Pediatrics Content Specification:


       Know the natural history of constitutional growth delay


3) 122 from 2010 answer A
Testosterone gels applied to the skin to maintain normal testosterone concentrations in men who
have hypogonadism have been reported to cause virilization in family members if used incorrectly.
After applying the gel to an area of skin that will be covered with clothing, the user should wash the
hands with soap and water to remove any residual testosterone. An individual using the preparation
should wait 5 to 6 hours before showering to allow full cutaneous absorption. If direct skin-to-skin
contact with another individual is anticipated, the area of application should be washed thoroughly.
Soap and water or alcohol will remove the testosterone from the skin. Unless the testosterone gel
has been applied to room surfaces and another individual comes into contact with the surfaces,
there is no need to limit room access. Both boys and girls can develop masculinization after
exposure to testosterone gels, so no children should have inappropriate exposure to these potent
medications.

American Board of Pediatrics Content Specification:


       Recognize that testosterone creams used by parents can cause virilization in male or female children


4) 106 from 2010 answer C
Age at puberty has a heritable component. In some families, the inheritance may be autosomal
dominant; in others, it seems polygenic. A 7-year-old girl whose mother reached menarche at an
early age and whose father was delayed in puberty, as described in the vignette, could have either
early or late puberty. However, early menarche at, for example, 9 years of age, would be associated
with some signs of breast development (thelarche) by 7 years of age.

Higher body mass index is associated with early puberty in girls, but not in boys. Adult body odor,
pubic hair, and acne are all signs of adrenal puberty (adrenarche or pubarche). This occurs more or
less independently of gonadal puberty, which, in girls, is identified clinically by the beginning of
breast budding (thelarche).

American Board of Pediatrics Content Specification:


       Understand the familial influences on the onset of puberty


5) 202 from 2010 answer B
The girl described in the vignette has a symmetrically enlarged, firm thyroid gland sometimes
referred to as a goiter. The most common cause of thyroid enlargement in adolescents is chronic
lymphocytic thyroiditis, or Hashimoto thyroiditis. This autoimmune disorder can be diagnosed in
most cases by measuring concentrations of antithyroid antibodies such as those directed against
thyroperoxidase (antimicrosomal or anti-TPO antibodies) or against thyroglobulin (antithyroglobulin
antibodies).

Abnormal thyroid function is not required to have chronic lymphocytic thyroiditis, although many
people who have this disorder develop hypothyroidism. The thyroid may enlarge during periods of
rapid growth of adolescence (ie, adolescent goiter) or increased need for thyroid hormone, as
during pregnancy, but it does not develop the firm consistency seen with chronic lymphocytic
thyroiditis. The girl described in the vignette has normal thyroid hormone and thyroid-stimulating
hormone (TSH) values, indicating that she could not have active Graves disease, which is
autoimmune hyperthyroidism. Iodine deficiency causes thyroid enlargement and elevated TSH
concentrations, but such deficiency is very uncommon in the United States, unless the child eats a
very restricted iodine-deficient diet. Thyroid cancer is rare in children and adolescents and usually
presents as a nodule within the thyroid or with cervical lymphadenopathy rather than symmetric,
smooth, firm thyroid enlargement.

American Board of Pediatrics Content Specification:


       Know that Hashimoto thyroiditis is the most common cause of goiter in adolescents


6) 218 from 2010 answer D
Thyroid fine-needle aspiration (FNA) biopsy, usually conducted under ultrasonographic guidance,
has revolutionized the management of thyroid nodules in adults. Depending on the series, almost all
malignancies are identified by aspiration biopsy (more than 95%), although some malignancies
cannot be diagnosed easily on FNA smear, and an area of malignancy may be missed in a complex
nodule. Nodules may be simple and cystic, simple and composed of follicular or papillary tissue, or
complex and composed of some areas that are cystic and other areas with follicular or components.
Calcitonin-secreting medullary carcinoma of the thyroid also may present as a nodule and is most
worrisome because of its resistance to therapy. Less than 10% of thyroid cancers in children are
medullary carcinomas. The risk of malignancy in an adult who has a thyroid nodule is less than
15%.

Because most thyroid carcinomas progress slowly, watchful waiting and careful observation after
biopsy may be all that is needed in the average adult. The results of FNA seem similar in children,
but the greater likelihood of a malignant lesion (a little less than 25%) and the longer life span of
children make many endocrinologists uncomfortable with observational management after a
negative biopsy. The risk of malignancy is higher in boys who have thyroid nodules, but the general
risk still is slightly less than 25% of all nodules in children. Any nodule that is not removed should
be monitored because an area of malignancy in a complex nodule could have been missed.

American Board of Pediatrics Content Specification:


       Know that a solitary thyroid nodule may be a sign of thyroid cancer


7) 138 from 2010 answer A
Children who have primary adrenal insufficiency (Addison disease) are unable to retain sodium and
excrete potassium because of aldosterone deficiency. They have low concentrations of cortisol and
high concentrations of circulating adrenocorticotrophic hormone (ACTH). They become dehydrated
and break down muscle tissue, developing hyponatremia, hyperkalemia, an elevated blood urea
nitrogen, and acidosis. Their urine electrolytes (increased sodium and decreased potassium) reflect
the aldosterone deficiency.

Children who have ACTH deficiency (ie, secondary adrenal insufficiency) also manifest the effects of
cortisol deficiency: weight loss, nausea, and inability to maintain blood pressure. They often have
hyponatremia because the low intravascular volume resulting from cortisol deficiency leads to
release of vasopressin. Because they can release aldosterone, they do not develop hyperkalemia.
They also do not develop hyperpigmentation.

American Board of Pediatrics Content Specification:


       Know how to use laboratory tests effectively for the diagnosis of Addison disease


8) 58 from 2009 answer C
Weight gain from exogenous obesity can be confused with Cushing syndrome, but glucocorticoid
excess, as seen in Cushing syndrome, almost always is associated with attenuation of normal
growth, as documented with Growth Chart C (Item C58C). The other growth charts are more typical
for exogenous obesity, with height either enhanced or unchanged in the presence of weight gain.
Other signs and symptoms of Cushing syndrome include hypertension, violaceous skin striae (Item
C58B), "buffalo hump" and muscle weakness because of loss of muscle mass, centripetal obesity,
cushingoid facies, easy bruisability, hirsutism, failure of pubertal progression or amenorrhea in
women, loss of libido in men, headache, depression, and dysphoria. Comparison of school
photographs from past years can be a useful exercise, although the clinical diagnosis of pituitary
Cushing syndrome (Cushing disease) can be difficult.

Documentation of several elevated 24-hour urine free cortisol measurements as well as elevated
overnight dexamethasone-suppressed serum cortisol, evening salivary cortisol, or midnight serum
cortisol values aid in diagnosis. However, children who are very obese, stressed, or depressed may
have inappropriate elevations in serum or urine cortisol values, and children who have mild Cushing
disease may have normal values on one or more occasions.

American Board of Pediatrics Content Specification:


       Recognize the signs and symptoms of Cushing syndrome


9)234 from 2009 answer D
The hemoglobin A1c (HbA1c) is a measure of nonenzymatic glycosylation of hemoglobin A and
correlates with concentrations of circulating blood glucose over the life of the red blood cell. It is not
a useful measure of daily changes in blood glucose or of amplitude of excursion of blood glucose
over the course of a day. Because the red cell has a life of approximately 120 days, measurement of
HbA1c more frequently than every 2 months is not likely to be helpful in clinical management. In
general, this measurement is made every 2 to 3 months. Results permit broad adjustments in
insulin therapy and monitoring of large trends in management. If the HbA1c is measured less
frequently, glycemic control may deteriorate without recognition. As children have been reported to
say, it is "the test that does not lie." It is useful in a child of any age, although the presence of fetal
hemoglobin in very young children may make interpretation of the results more difficult. In addition,
measurement of HbA1c in children who have hemoglobinopathies may not be entirely accurate.
Instead, measurement of total glycosylated hemoglobin can be substituted. For children who have
rapid red cell destruction, the published relationship between serum glucose and HbA1c may be
inaccurate.

Self blood glucose monitoring gives a relatively dynamic picture of blood glucose changes over the
course of a day and allows decisions to be made about adjustment of basal insulin requirements as
well as adjustments for meals, exercise, and other life activities. A combination of self blood glucose
monitoring and periodic measurement of HbA1c permits reasoned decisions and improved glycemic
control in this most difficult disorder.

American Board of Pediatrics Content Specification:


       Know the value of hemoglobin A1c in the management of type 1 diabetes


10) 177 from 2009 answer B
The chronic heartburn and dysphagia to solid foods, primarily meats, described for the boy in the
vignette strongly suggest either reflux esophagitis (possibly with an esophageal stricture) or
eosinophilic esophagitis (EE) (Item C177A). The most appropriate next test to evaluate the
dysphagia is esophagogastroduodenoscopy with biopsies. The endoscopy can characterize the
severity of inflammation, exclude Barrett esophagus (a premalignant complication of
gastroesophageal reflux [GER]), and potentially differentiate between GER and EE. Esophageal
manometry, radionuclide gastric emptying scan, measurement of serum immunoglobulin E, and 24-
hour esophageal pH probe study are potentially useful in the evaluation of GER or allergy, but they
are not the appropriate initial tests in evaluating solid food dysphagia.

GER is defined as excessive regurgitation of gastric contents (both acid and nonacid) into the
esophagus. The most common gastrointestinal symptoms are heartburn (pyrosis), dysphagia
(difficulty swallowing), and odynophagia (painful swallowing). GER also may result in extraintestinal
symptoms, including hoarseness, chronic cough, exacerbation of asthma, apnea, and aspiration
pneumonia. GER is extremely common in childhood. According to one cross-sectional study, 3% to
5% of healthy children report reflux symptoms at any given time. Because GER frequently is mild
and self-limited, empiric therapy with an antacid, histamine receptor blocker, or proton pump
inhibitor is appropriate and can alleviate symptoms. Prolonged, persistent reflux (ie, more than 3
months) or complicated reflux (ie, associated with hematemesis or respiratory symptoms) warrants
further evaluation. Among the useful tests to evaluate GER are upper gastrointestinal radiographic
series (which excludes malrotation and hiatal hernia), pH probe study or esophageal impedance
(which determine the extent and duration of reflux over a 24-hour period), gastric emptying scan
(which rules out gastroparesis), and esophageal motility evaluation (which assesses peristalsis and
esophageal sphincter pressure). Upper endoscopy with biopsy generally is the most valuable test
because it can determine if chronic GER has caused any esophageal injury (Item C177B).

In the past 10 years, researchers have recognized that not all heartburn or dysphagia is caused by
GER. EE presents similarly to reflux, but is believed to be an atopic condition. Affected patients tend
to have more dysphagia symptoms than heartburn. Often, there is a history of meat impaction in
the esophagus. As noted previously, upper endoscopy with biopsies frequently can differentiate
between the two conditions. GER usually is characterized by ulceration and injury limited to the
distal 5 cm of the esophagus. In contrast, EE is characterized by inflammation of the proximal,
middle, and distal esophagus, with large numbers of eosinophils seen on biopsy. Differentiating
between these two conditions is important because treatment of GER involves acid blockade. In
contrast, the therapies for EE include anti-inflammatory therapy (eg, fluticasone, budesonide), acid
blockade, or elimination diets.

American Board of Pediatrics Content Specification:


       Know the methods for evaluation of gastroesophageal reflux


11) 161 from 2010 answer B
The concomitant findings of abdominal distention and an obstructive gas pattern on abdominal
radiography (Item C161A) reported for the boy in the vignette strongly suggest either a functional
or mechanical small bowel obstruction. In adults, postoperative adhesions are the leading cause of
small bowel obstruction, comprising nearly 75% of cases in one study. However, small bowel
obstruction due to postoperative adhesions is much less common in children. In one pediatric study,
the overall incidence of bowel obstruction was 1.1% during the 5 years after primary surgery. The
highest risk occurred after ileal surgery (9.2%), followed by exploratory laparotomy (6.5%) and
duodenal surgery (4.7%). For children undergoing appendectomy, readmission for obstruction
occurred in only 0.3% of cases.

Regardless of the specific cause, the initial goal of therapy for the child who has either functional or
mechanical bowel obstruction is to relieve the associated signs and symptoms, manifested in the
boy in the vignette by abdominal distention and bilious emesis, with the latter sign suggesting
complete bowel obstruction. Relief can be achieved for this boy by immediate institution of
nasogastric decompression. Although intravenous fluids and bowel rest eventually will be instituted,
the first goal of therapy is intestinal decompression. Computed tomography scan plays little primary
role in management but may be useful in identifying suspected obstructing lesions. Barium enema
may be considered in children whose age and mode of presentation suggest a diagnosis of
intussusception. Finally, emergency surgical intervention should be undertaken only after achieving
decompression and identifying the site of obstruction with an upper gastrointestinal tract contrast
radiographic series, at least to the ligament of Treitz (to detect intestinal malrotation) and with
small intestinal follow-through if needed.

The overall incidence of postappendectomy adhesive small bowel obstruction is low, but adhesions
develop with a much higher frequency when the surgical presentation is complicated by appendiceal
perforation. Lesions causing partial or complete luminal obstruction distal to the ligament of Treitz
often present with bilious vomiting. In the newborn period, this is an ominous sign that suggests a
surgical diagnosis, including intestinal stenosis, atresias, and malrotation with or without volvulus.
Beyond infancy, the significance of bile-stained vomiting is less clear. In one report of 230 children
presenting to an emergency department because of yellow or green emesis, only 20 were
determined to have a surgical disease. In another pediatric study of 44 patients who required a
Ladd procedure for malrotation and midgut volvulus, 80% presented with green bilious emesis.

The most common causes of bilious vomiting are shown in (Item C161B). Considering the clinical
history and age at presentation of the boy in the vignette, postoperative adhesive small intestinal
obstruction represents the most likely diagnosis. Once nasogastric decompression is achieved,
further management must include additional diagnostic studies and consideration of surgical
intervention. Prior data have shown that plain roentgenograms alone often are sufficient for
identifying intestinal malrotation by demonstrating a characteristic gas pattern. In the newborn
period, bilious vomiting should be considered a consequence of mechanical bowel obstruction until
proven otherwise. Once initial bowel decompression has been achieved, a small intestinal contrast
study can identify the nature and location of the obstructing lesion prior to surgery. In older
patients, for whom malrotation with volvulus is much less prevalent, the timing of additional
diagnostic studies depends on the response to nonoperative management. Prior investigations in
patients who had adhesive small intestine obstructions have demonstrated that a significant
percentage may respond to nasogastric decompression alone, obviating the need for emergency
surgery. Under these conditions, intestinal contrast studies using water-soluble contrast material
may be used to confirm luminal integrity and guide further therapy.

American Board of Pediatrics Content Specification:


       Formulate a management plan for a patient with postoperative intestinal obstruction


12) 177 from 2010 answer B
The adolescent described in the vignette has erratic eating habits and presents with the recent
onset of a small-volume, infrequent stooling pattern. Physical examination reveals no obvious
abnormalities, and rectal examination demonstrates normal anal sphincter tone and a rectal vault
devoid of feces. This young woman is exhibiting nonretentive (nonwithholding) constipation that
should be treated with a diet that includes increased fluid intake and a commercially available fiber
supplement such as methylcellulose.

The dietary history and absence of feces in the rectal vault reported for the girl in the vignette
suggest that a more conservative approach that does not encompass medications may be
attempted initially. Recent evidence indicates that fiber supplements for constipation management
are an important addition to the therapeutic armamentarium, particularly for those in whom dietary
history suggests poor fiber intake. Multiple fiber supplements are available over the counter, and
two of the most frequently used are psyllium and methylcellulose. No available evidence suggests
superiority of one formulation over another; patients should be encouraged to use whichever
product is the most palatable to them, thus assuring the greatest likelihood of compliance.
Depending on the patient's response to this nonpharmacologic approach, therapy using an osmotic
agent may be added after an adequate trial of the fiber supplement.

Constipation comprises nearly 5% of all primary care pediatric and nearly 25% of all pediatric
gastroenterology visits in the United States. Although many factors, including physiologic, anatomic,
and psychological disorders may be involved, most affected children exhibit no identifiable
pathologic condition, and the term "functional constipation" is applied to their condition. In the
young child, constipation most commonly is the consequence of hard, painful bowel movements that
lead to voluntary stool withholding. Stress, dietary changes, toilet training, and being "too busy" to
use the bathroom are among the many precipitating factors. Prolonged withholding results in fecal
stasis and fluid reabsorption in the colon, with an increase in stool size and consistency. Physical
findings often include mild abdominal distention and a palpable stool mass in the left lower
quadrant. Rectal examination typically demonstrates a rectal vault filled with firm stool, often
extending to the anal verge.

A careful history and physical examination should direct the clinician to prescribing an appropriate
course of therapy. For children who have stool withholding (with or without encopresis), behavior
modification may be beneficial as an adjunct to medical therapy, particularly for the patient older
than 5 years of age. However, treatment should include some form of pharmacologic intervention.

Oral medications used in the treatment of constipation fall into three defined categories: osmotic
agents, lubricants, and stimulants. Each drug class possesses a different mechanism of action. In
general, stimulants (eg, senna, bisacodyl), which promote enhanced colonic transit, should be
avoided as long-term therapy, although they may have some efficacy during an initial "clean-out"
period. Lubricants such as mineral oil have long been used as stool-softening agents and to reduce
withholding while promoting rectal evacuation. Although mineral oil-containing laxatives
theoretically may interfere with vitamin absorption, no available evidence supports this assertion.
Currently, the most frequently used medications for treatment of functional constipation are the
osmotic agents, including lactulose (a synthetic disaccharide), sorbitol, and polyethylene glycol (PEG
3350). These agents increase intestinal intraluminal osmolality, thereby inducing water movement.
A softer, larger volume of stool is produced, with gradual dissolution of hard fecal matter. These
medications are well tolerated long-term, and their doses may be titrated to achieve maximal
effectiveness. Recent evidence indicates that PEG 3350 has greater palatability and acceptance over
all age ranges, and preliminary clinical data suggest that polyethylene glycol is safe and effective in
infants. However, recommendations regarding its use in children younger than 1 year of age must
await further clinical trials. Magnesium hydroxide also acts as an osmotic agent, but abdominal
cramping and the risk of overdosing, leading to hypermagnesemia, hypophosphatemia, and
secondary hypocalcemia, make this a less desirable alternative for long-term use.

American Board of Pediatrics Content Specification:


       Know the action of laxatives, stool softeners, and lubricants


13) 52 from 2010 answer e
The infant described in the vignette has breastmilk jaundice (BMJ), which is defined as indirect
hyperbilirubinemia in a breastfed newborn that develops after the first 4 to 7 days following birth,
persists longer than physiologic jaundice, and has no other identifiable cause.

For healthy term infants who have BMJ and bilirubin values of 12 to 17 mg/dL (205 to 291
mcmol/L), the following options may be considered:


       Ensure breastfeeding 8 to 12 times per day and remeasure the serum bilirubin in 12 to 24 hours,
        reassuring the mother about the relatively benign nature of BMJ. If needed, breastfeeding also can be
        supported with manual or electric pumps or other techniques that assist the mother in maximizing the
        infant's intake of breast milk.
       Continue breastfeeding and supplement with formula.
       Temporarily interrupt breastfeeding.




Temporary interruption of breastfeeding for 12 to 24 hours usually results in a rapid decrease in
bilirubin concentrations but is only recommended for otherwise healthy term infants whose serum
bilirubin values are at least 20 mg/dL (342 mcmol/L). To maintain milk production and minimize
discomfort for the mother, breasts should be pumped and the milk stored for later use.

Phototherapy is not indicated for the healthy term infant who has uncomplicated jaundice and a
bilirubin valve of 16.0 mg/dL (273.7 mcmol/L). Use of sunlight is not recommended because of
reliability and safety issues involved in exposing an unclothed newborn to sunlight.
Use of supplemental intravenous fluids is invasive and generally unnecessary in the infant who is
otherwise healthy, well hydrated, and responding to therapy.

American Board of Pediatrics Content Specification:


       Know the management of the infant with breast milk jaundice


14) 41 from 2010 answer b
Gastrointestinal (GI) bleeding is a common pediatric problem, but life-threatening GI hemorrhage is
relatively rare. The location of acute bleeding (above or below the ligament of Treitz) can be
determined initially by inserting a nasogastric tube. If blood is recovered, the source is the upper GI
tract. Common causes of hematemesis (vomiting of bright red blood) include swallowed blood (eg,
from epistaxis, tonsillectomy), esophagitis, Mallory-Weiss tears, reactive gastritis (eg, "stress ulcer"
due to alcohol, nonsteroidal anti-inflammatory drugs, critical illness, radiation), peptic ulcer, and
esophageal varices (due to portal hypertension).

The child described in the vignette has significant liver disease caused by underlying biliary atresia
with resultant portal hypertension, as evidenced by the dilated collateral veins seen on her
abdominal wall. Portal hypertension, defined as portal pressures greater than 10 mm Hg, is caused
by obstruction to portal blood flow due to intra- or extrahepatic causes. Collateral vessels often form
to shunt blood to the systemic circulation, but portal flow remains high, as do portal pressures.
Collateral vessels are seen commonly in the esophagus; they may dilate and rupture as the result of
chronically elevated pressures. In addition, sudden rises in pressure, such as seen with coughing,
can produce acute rupture.

Although epistaxis and gastric stress ulcers can cause hematemesis, esophageal varices are a much
more likely cause of this child's bleeding because of her underlying clinical condition. Infectious
enterocolitis and Meckel diverticulum are both causes of lower GI bleeding and typically present as
either hematochezia (passage of bright red blood per rectum) or melena (passage of black, tarry
stools).

American Board of Pediatrics Content Specification:


       Recognize that esophageal varices may first present with upper gastrointestinal bleeding


15) 209 from 2010 answer D
The young college student described in the vignette presents with typical symptoms of upper
gastrointestinal tract damage that have increased in severity after attending a party the previous
evening. Physical examination reveals epigastric tenderness and evidence of occult gastrointestinal
tract bleeding. These signs point to an alcohol-induced problem, in this case, alcoholic gastritis.
Although specific medical therapy aimed at gastric acid blockade may be prescribed, the most
important course of action is to obtain a careful history, including recent exposure to drugs or
alcohol, and to urge the young man to refrain from alcohol consumption. Although abstinence for at
least 1 month would be the recommendation for adults before resuming alcohol consumption in
moderation, this young man should be counseled to resume consumption only upon achievement of
legal age.

Physiologically, ethanol is a well-described esophageal and gastric mucosal toxin, inducing both
erosive lesions and frank hemorrhage. Chronic alcohol abuse has been associated with the
development of atrophic gastritis as well as with esophageal cancer. Studies in humans demonstrate
that adults who consume alcohol, even in moderation, may develop subepithelial gastric mucosal
hemorrhage and edema but show little evidence of a mucosal or submucosal inflammatory
response. Follow-up endoscopies demonstrate that the gastric lesions disappear rapidly following
abstinence from alcohol intake.

In addition to recommending that alcohol intake be curtailed, standard acid-blocking therapy may
be prescribed for this patient to reduce the likelihood of acid injury to an already damaged mucosa.
Depending on clinical severity, once- or twice-daily therapy with a proton pump inhibitor may be
prescribed. The maximum dose for lansoprazole is 30 mg bid, although once-daily therapy usually is
adequate in uncomplicated cases. Sucralfate is an aluminum-containing sulfated derivative of the
disaccharide sucrose. When ingested orally, it forms a gel that adheres to inflamed esophageal and
gastric mucosa as well as to gastric and duodenal ulcer beds, thus creating a protective barrier
against further acid-mediated damage. Sucralfate may be used in the acute, primary management
of peptic ulcer disease, but it is administered more commonly as adjunctive therapy. Endoscopic
evaluation should not be required for the young man in the vignette unless he fails to respond to
conservative medical therapy.

Determination of H pylori serum antibodies is of limited utility because bacterial colonization, with
the appearance of positive antibody titers, occurs in many healthy individuals by the end of the
second decade of life. In the United States and Canada, the overall prevalence of positive H pylori
antibodies is 35% to 45%. Furthermore, although a positive antibody titer indicates bacterial
colonization, it does not predict a cause-and-effect relationship between infection and inflammation.
Other diagnostic modalities (13C-urea breath testing, fecal H pylori antigen) are under evaluation,
but upper endoscopy with biopsy remains the gold standard for diagnosing H pylori gastritis in
pediatrics. Although several published reports have attempted to link alcoholic gastritis to an
association with H pylori infection, other studies note that ethanol (particularly when consumed in
red wine) actually may inhibit bacterial colonization.

Approximately 40% of college students are binge drinkers, but the incidence of alcoholic gastritis
among college students is unknown.

American Board of Pediatrics Content Specification:


       Recognize the importance of alcohol-induced gastritis in adolescents, and manage appropriately


16) 193 from 2010 answer C
The physical finding of hepatomegaly may be associated with myriad clinical conditions, reflecting
either intrinsic liver disease or a more generalized disorder. The obesity of the patient described in
the vignette (calculated body mass index = weight (kg)/height2(m) = 27.3), coupled with the
findings of a liver edge palpable 2.5 cm below the right costal margin and mild elevations in liver
enzymes, suggest the presence of nonalcoholic fatty liver disease (NAFLD). However, a definitive
diagnosis of NAFLD may be established only after careful consideration of other possible causes of
hepatomegaly.

The most important diagnosis to rule out immediately for this boy is Wilson disease because the
history of recent problems at school suggests the potential for new-onset Wilson-associated
neurobehavioral dysfunction. This disorder may be discerned by measuring serum ceruloplasmin. A
low value (<20 mg/dL [200 mg/L] in most, but not all cases) indicates the need for immediate
further evaluation, including an ophthalmologic exam, 24-hour urine copper excretion
measurement, and a liver biopsy for histology and assessment of hepatic copper content.

A palpable liver edge below the right costal margin does not necessarily indicate enlargement.
Normative data for liver size are based on assessment by percussion, and imaging studies generally
are not performed in the routine assessment of hepatomegaly. Liver size increases linearly with
both body weight and height. In a 12-year-old child, the mean normal liver span is 7 to 8 cm in
boys and 6 to 7 cm in girls. However, whenever a palpable liver edge is found on physical
examination, a distance below the right costal margin of more than 2 cm in children and more than
3.5 cm in newborns should be considered abnormal. The finding of hepatomegaly, by itself,
suggests neither the diagnosis nor the prognosis of liver disease. Rather, depending on patient age,
this observation, in conjunction with a careful history and the presence of other physical findings,
should determine the course of diagnostic evaluation.
A careful history and physical examination are required to direct the initial evaluation toward the
likely pathophysiologic mechanism for hepatic dysfunction: inflammatory, excess storage (fat,
glycogen, metals, abnormal proteins), infiltrative, congestive, or obstructive. In this case, the
patient's obesity predisposes him to manifest the hepatic steatosis associated with NAFLD, and the
liver enzyme elevations also indicate secondary hepatic inflammation (a common consequence of
storage diseases). Questioning about travel history, sick contacts, drug or environmental toxin
exposure, and exposure to blood products can indicate risk factors for acute hepatitis. Systemic
symptoms in the older child may herald the presence of chronic inflammatory or autoimmune
conditions; a history of jaundice, dark urine, or acholic stools indicates cholestasis due to
inflammatory or obstructive causes. In the older child, findings of new-onset behavioral or
neurologic dysfunction, especially in the setting of chronic liver disease, may indicate hepatic
decompensation. In the case of Wilson disease, such findings are the consequence of copper
accumulation in the central nervous system, which may be confirmed by identifying Kayser-Fleisher
rings on ophthalmologic evaluation.

The most important task for the clinician who is evaluating hepatomegaly in the pediatric patient is
to identify serious liver disease at the time of initial presentation. Hepatomegaly, as a marker of
chronic liver disease, is associated with many findings that suggest an inflammatory, obstructive, or
infiltrative process (Item C193A). It may represent a transient observation accompanying a
systemic viral illness, and the finding of hepatic tenderness indicates acute inflammation. Persistent
liver enlargement warrants further evaluation. When the liver edge is firm or hard, a storage or
infiltrative disorder must be considered, and this finding often is associated with splenomegaly. A
hard, thin, or nodular liver edge suggests cirrhosis, and consequent portal hypertension is
accompanied by splenomegaly.

Laboratory studies performed in the assessment of hepatomegaly should be directed initially at
determining the extent of hepatic inflammation or dysfunction (Item C193B). Albumin and
prothrombin time are used to monitor hepatic synthetic capacity; aminotransferases can assess
inflammation; and fractionated bilirubin, alkaline phosphatase, and gamma-glutamyl transpeptidase
are used to evaluate cholestasis. Once abnormal test results demonstrate liver disease, secondary
studies are directed at establishing a specific diagnosis.

In the absence of a history suggesting systemic involvement, a high-risk infectious or toxic
exposure, or abnormal physical findings (eg, jaundice, splenomegaly), a logical approach is to
perform the initial screening laboratory tests, which in this case demonstrated only mild
aminotransferase elevations, prior to proceeding with a more extensive evaluation. Because the boy
in the vignette demonstrates no hepatic decompensation, he can be monitored for 2 to 3 months. At
the end of this monitoring period, if liver enzyme values remain abnormal, further testing should be
performed. Such secondary evaluation includes alpha-fetoprotein, antismooth muscle antibody,
hepatitis B serology, and lipids.

American Board of Pediatrics Content Specifications:


       Know the significance of hepatomegaly in a 12-year old
       Know how to evaluate a child with hepatomegaly


17) 241 from 2010 answer c
Distal intestinal obstruction syndrome (DIOS), formerly referred to as meconium ileus equivalent, is
a common gastrointestinal complication in patients who have cystic fibrosis (CF). It is of particular
concern among those for whom intestinal maldigestion/malabsorption, a problem that invariably is
associated with the delta-F508 homozygous state, remains poorly controlled. DIOS is suggested for
the boy in the vignette by the findings of decompensated malabsorption, constipation, and
abdominal discomfort and distention. The physical finding of a right-sided abdominal mass further
supports this diagnosis.

CF is the most common heritable disorder among whites in the United States, with a gene frequency
of approximately 1 in 29 in this population. Overall incidence figures indicate that CF affects
approximately 1 in 3,500 children of Caucasian descent, with the incidence in other populations of
approximately 1 in 11,500 (Hispanics), 1 in 20,000 (African Americans) and 1 in 90,000 (Asians). It
is transmitted in an autosomal recessive pattern, with heterozygotes being unaffected. Although
more than 2,000 CF gene mutations have been described, approximately 70% of CF alleles in the
United States demonstrate the delta-F508 mutation on chromosome 7, where a phenylalanine
residue is deleted at position 508 of a 1,480-amino acid protein. Approximately 50% of CF patients
are homozygous for this mutation, which is associated with severe disease. The consequent
metabolic defect involves mutation in the cystic fibrosis transmembrane conductance regulator
(CFTR), resulting in abnormal chloride and water secretion across epithelial surfaces of all exocrine
organs. This causes abnormally thick and viscid secretions, leading to dysfunction in multiple
systems, including the lung, liver, pancreas, and gastrointestinal tract.

DIOS results from inspissation of viscous mucus and fecal material in the ileum, cecum, and
ascending colon. It is a relatively common problem in CF, reported in 10% to 20% of patients. DIOS
occurs with greatest frequency in older children and adolescents. Predisposing factors (apart from
the primary CFTR defect) include poorly controlled fat malabsorption, previous meconium ileus, low
dietary fiber intake, and possibly prolonged intestinal transit time. Interestingly, although DIOS has
been reported in CF patients who retain relatively normal pancreatic exocrine function, the
syndrome has not been reported in other forms of pancreatic insufficiency, likely because of the
contribution of abnormal luminal fluid content in CF.

Acute management of DIOS involves the use of a variety of bowel-cleansing agents, depending on
the degree of involvement. Intestinal lavage with a balanced electrolyte solution containing
polyethylene glycol, use of oral N-acetylcysteine as a mucolytic agent, and high-dose diatrizoate
meglumine and diatrizoate sodium (via both oral and rectal instillation) have been employed
successfully. The particular cleansing protocol often varies with the institution. Chronic management
should include optimizing fat absorption plus the use of cathartic agents and appropriate intake of
fiber.

Although DIOS is a relatively common gastrointestinal complication of CF, other problems must be
considered in any patient who has CF and presents with gastrointestinal complaints. Some of the
more prevalent, age-related problems are listed in (Item C241). Presenting signs and symptoms of
these disorders are similar to those in patients who do not have CF, and the clinician caring for
patients who have CF must be aware of their occurrence in this patient group.

A diagnosis of appendiceal abscess or Crohn disease is unlikely in this case because of the absence
of associated symptoms of right lower quadrant abdominal pain, fever, or diarrhea. Functional
constipation may exhibit one or more of the clinical findings described for this child, but the
relatively recent onset in a child who has no history of stool withholding behavior, coupled with his
malabsorptive state and increase in pancreatic enzyme requirement, points to DIOS as the most
likely diagnosis, particularly considering its importance and frequency in patients who have CF.

Fibrosing colonopathy is an uncommon complication of pancreatic enzyme supplementation. This
iatrogenic disorder results in colonic stricturing, often requiring surgical resection, and is associated
with pancreatic enzyme supplementation in excess of 24,000 lipase units/kg per day. The risk of
fibrosing colonopathy was particularly high when pancreatic enzymes were provided in a high-
strength microencapsulated form (>20,000 lipase units per capsule), which no longer is marketed.
Due to enzyme reformulation that reduced the lipase content per capsule and current
recommendations limiting maximal lipase supplements to 10,000 enzyme units/kg per day, the
incidence of fibrosing colonopathy has been reduced dramatically.

American Board of Pediatrics Content Specification:


       Know the age-related gastrointestinal signs and symptoms of cystic fibrosis
18) 181 from 2010 answer B


The gallop rhythm, hepatomegaly, and jugular venous distention described for the boy in the
vignette support the diagnosis of congestive heart failure (CHF), most likely due to myocardial
dysfunction associated with dilated cardiomyopathy. Generally, CHF is a clinical syndrome that
reflects the inability of the myocardium to meet the metabolic requirements of the body, including
those for growth. The presentation in the older child differs from that of the young infant. In the
former, CHF usually presents with signs and symptoms of fatigue, particularly with exercise or
activity. In addition, children may present with shortness of breath, palpitations, diaphoresis, and in
the most acute cases, extremis. Almost invariably, the left ventricle is affected, and as its systolic
and diastolic function diminishes, its filling pressures increase. Clinically, this may manifest during
auscultation as a gallop rhythm. The increased left ventricular filling pressures results in rising
pressures in the pulmonary veins, pulmonary capillaries, pulmonary arteries, right ventricle, and
right atrium. When the right-sided filling pressures increase, the systemic veins that drain into the
right atrium, including those of the hepatic system and the jugular system, become congested.
Congestion of the former leads to hepatomegaly and that of the latter may manifest with jugular
venous distention discernible on examination.

Laboratory support for the myocardial failure seen in patients who have CHF can be demonstrated
by an elevation in the brain natriuretic peptide value. Results of this test almost always are
abnormal in patients who have significant CHF.

Among the many causes of CHF are large-volume left-to-right shunts with pulmonary
overcirculation, pressure load on the myocardium, inadequate blood flow to the myocardium,
infection or infiltration of the myocardium, or genetic or idiopathic diseases of the myocardium. CHF
from large-volume shunting lesions is seen almost exclusively during infancy. The other causes may
manifest any time throughout infancy, childhood, or adolescence.

Anemia can lead to a "high-output" state but does not present with the right heart failure
demonstrated by the patient in the vignette. Although Kawasaki disease can present in some cases
with CHF due to acute myocarditis, the patient in the vignette has no other physical findings to
support this diagnosis. Primary pulmonary hypertension is seen more typically in females during
adolescence or adulthood and includes the presence of a loud second heart sound with or without a
gallop rhythm. Pulmonary embolism typically presents more acutely with chest pain, hypoxemia,
and tachypnea in addition to the findings of acute right heart failure.

American Board of Pediatrics Content Specification:


       Identify edema, hepatomegaly, jugular vein distension, cardiomegaly, and gallop rhythm as important
        physical findings in congestive heart failure in older children


19) 37 from 2010 answer C


Tetralogy of Fallot (TOF) is the most common form of cyanotic congenital heart disease, with an
incidence of approximately 0.2 in 1,000 live births and accounting for 9% of all congenital heart
disease. The four components of TOF are right ventricular outflow/pulmonary stenosis, ventricular
septal defect (VSD), overriding aorta, and right ventricular hypertrophy (Item C37). The primary
lesion is underdevelopment of the pulmonary infundibulum, which has led some to refer to this
disease as "monology of Fallot" because all aspects of the tetrad result from this lesion. The result
of underdevelopment of the pulmonary infundibulum is deviation of the infundibular septum
anteriorly and superiorly, bringing it into the right ventricular outflow tract. This leads to obstructed
right ventricular outflow and the commonly seen underdevelopment of the pulmonary valve and
pulmonary arteries caused by diminished blood flow through these structures. The underdeveloped
pulmonary infundibulum also creates a VSD, which is almost universally large and of the
malalignment type. The defect resulting from anterior malalignment of the infundibulum allows the
aorta to "override" the ventricular septum. Finally, right ventricular hypertrophy results from
exposure to systemic pressures (large VSD and pulmonary stenosis).
Most patients who have TOF do not present with cyanosis in the newborn period, but rather come to
medical attention because of a harsh systolic murmur. The murmur results from infundibular
stenosis and pulmonary stenosis, not from the VSD. The second heart sound is single. Because the
degree of pulmonary blood flow obstruction can vary among patients, the degree of systemic
oxygen desaturation ranges from mild to severe. Children who have mild obstruction may appear
"pink," and those who have severe pulmonary stenosis have significantly reduced pulmonary blood
flow and an increase in right-to-left shunting across the VSD into the aorta, leading to more
pronounced cyanosis. Furthermore, as pulmonary blood flow decreases with tight pulmonary
stenosis, pulmonary venous return to the left atrium decreases, resulting in less highly saturated
blood leaving the left ventricle and entering the aorta. Conversely, mild pulmonary stenosis is
associated with more pulmonary blood flow, less right-to-left intracardiac shunting, and less
systemic desaturation. In the mildest cases, there is left-to-right shunting across the VSD and near-
normal or normal systemic saturation.

A decreased or absent murmur signifies diminished pulmonary blood flow, as occurs in the cyanotic
spell or tetralogy spell. Such spells are marked by distress, crying, inconsolability, hyperpnea, and
increasing cyanosis, as described for the infant in the vignette. They frequently occur in the morning
or at times of dehydration (eg, fever, gastroenteritis). If not treated quickly, cyanotic spells can lead
to serious morbidity and even death.

Treatment of cyanotic spells centers on increasing pulmonary blood flow, which is accomplished by
several means. The first step is to alter the ratio of relative resistance of pulmonary and systemic
beds. Increasing the systemic vascular resistance relative to the pulmonary vascular resistance
decreases the right-to-left shunt at the VSD and can be accomplished by placing the patient in a
knee-to-chest position or by squatting in older children. Pharmacologic augmentation of the
systemic vascular resistance can be achieved with intravenous phenylephrine. Therapy also includes
the use of sedation with morphine, which suppresses the sensation of suffocation and can relieve
the patient's fear. The use of high-flow oxygen, which dilates pulmonary vasculature, constricts
systemic vasculature and increases PO2 of pulmonary venous return, and generous intravascular
fluid administration to increase preload are important therapies for the patient experiencing a
tetralogy spell.

Clubbing of the digits can be seen in cyanotic heart disease as well as a variety of other entities, but
it is not typical in patients younger than 1 year of age and its presence is not associated with a
tetralogy spell. Hepatomegaly is uncommon in the infant who has TOF; its presence suggests right
heart failure. Diminished oxygen saturation is a component of a tetralogy spell, although the
physical findings and condition of the patient, not the oxygen saturation, define the spell. Finally, an
S3 gallop rhythm can be heard in the patient who has myocardial failure but is not expected in a
patient who has TOF, particularly with the pronounced tachycardia described for the patient in the
vignette.

American Board of Pediatrics Content Specification:

Identify the clinical characteristics of a tetralogy spell


20) 53 from 2010 answer C


Cerebrovascular accidents can occur in patients affected by congenital heart disease as a result of
perioperative surgical complications, hemodynamic abnormalities, intracranial abscess, or
endocarditis. Patients who have chronic cyanotic heart disease, such as the boy described in the
vignette, are at additional risk for cerebrovascular accident due to paradoxic emboli and a relative
anemia.

Paradoxic emboli result from the right-to-left intracardiac shunting of blood such that an embolus
that originates in the systemic venous system avoids the filtering function of the pulmonary
vasculature and crosses from the right to the left side in the heart, thereby gaining access to the
systemic circulation, including the cerebral circulation. Stroke from relative anemia may result from
complex interactions of iron-deficient blood in the cerebral circulation, including the decreased
oxygen-carrying capacity of iron-deficient blood. In addition, the microcytes formed under
conditions of relative anemia are less deformable than those formed in an iron-rich environment,
and such "structural" erythrocyte changes may be associated with an increased viscosity despite the
lower hemoglobin concentration. The higher viscosity leads to more resistance to flow, and the
altered flow in the cerebral microvasculature can result in cerebrovascular accident.

Hypoglycemia might lead to abnormal speech, both in terms of content and patterns, but this would
not be expected to occur over the course of 1 hour in the absence of other symptoms.
Hypothyroidism would not be expected to present with slurring of speech. Polycythemia can be
associated with increased viscosity and, therefore, decreased flow through small cerebral vessels, as
mentioned previously. However, iron deficiency in the presence of polycythemia poses a greater risk
for stroke. Finally, Wolff-Parkinson-White syndrome would be expected to present with palpitations,
diaphoresis, or chest pain, but not slurring of speech in isolation.

American Board of Pediatrics Content Specification:


       Know that a relative anemia can be associated with a stroke in a patient with cyanotic heart disease


21) 105 from 2010 answer E


Adequate tissue oxygenation requires a complex interaction between the pulmonary, cardiovascular,
and hematologic systems and can be disturbed by a variety of disease processes. Continual supply
of oxygen is imperative because cells lack the ability to store oxygen. Imbalances between tissue
demand and supply result in cell injury and death.

The amount of oxygen transport in the blood is dependent on three factors: hemoglobin
concentration, cardiac output, and the amount of hemoglobin that is saturated with oxygen.
Although a small amount of oxygen is dissolved in blood, most is carried by hemoglobin, as
expressed in the equation for arterial oxygen content (Cao2):

                   Cao2 (g O2/mL)= (hemoglobin x 1.34 x SaO2) + (0.003 x Pao2)


The tissue delivery of oxygen (DO2) is calculated using the cardiac output (CO) and the Cao2 as
follows:

                                             DO2 = CO x Cao2


Oxygen delivery for the child described in the vignette can be improved most appropriately by
transfusion of packed red blood cells and correction of her anemia. Other interventions may be
beneficial but would not have the impact of transfusion. Reducing her fever with acetaminophen
would decrease tissue oxygen demand, increasing the diuretic dose might increase cardiac output if
her vascular volume is elevated, and increasing oxygen flow would increase the arterial oxygen
content. A reduction in the milrinone dose would decrease cardiac output and reduce oxygen
delivery.

American Board of Pediatrics Content Specification:


       Know how to manage the child with an hypoxic episode


22) 117 from 2010 answer D


The infant described in the vignette has typical findings of pulmonary stenosis, which often is
associated with a systolic click resulting from the abnormal structure and function of the pulmonary
valve. The click is caused by the opening of the thickened valve leaflets during systole. In contrast
to the normal thin and flexible semilunar valve leaflets, those of the stenotic pulmonary valve have
an accentuated sound that is referred to as an opening click. The murmur of pulmonary stenosis
results from systolic blood flow from the right ventricle across the abnormally narrowed orifice of
the pulmonary valve. The narrowing yields a diminished valve area through which the stroke
volume crosses, creating turbulence. Such turbulence is noted during auscultation as a systolic
ejection murmur and typically is heard best over the pulmonary valve and main pulmonary artery.
On the chest wall, these structures lie beneath the left sternal border, with extension cephalad
toward the left clavicle. Frequently, the murmur radiates into the back and the axillae as the sound
of turbulence follows the course of the branch pulmonary arteries.

Aortic stenosis also is associated with a systolic ejection click that does not change with position,
but the accompanying murmur is heard best at the upper right sternal border, with radiation into
the neck. The murmur associated with an atrial septal defect is not from the blood flow across the
atrial septum, which usually is nonturbulent and at low pressure. Rather, the systolic murmur
created by an atrial septal defect is the result of a relative pulmonary stenosis as the left-to-right
atrial shunt and resulting increased right ventricular volume must cross the pulmonary valve. In
contrast to pulmonary valve stenosis, there is no structural abnormality of the pulmonary valve and,
thus, no systolic click. Patent ductus arteriosus typically produces a continuous murmur
characterized as having a "machinery" quality that is usually loudest at the left infraclavicular area.
It is continuous because of the constant flow between the systemic and pulmonary circulation
resulting from the higher systemic vascular resistance compared with the pulmonary vascular
resistance throughout the cardiac cycle and the lack of a valve to separate the two circulations. The
murmur of a ventricular septal defect typically is holosystolic because the left-to-right shunt at the
ventricular level begins with the onset of systole, even before the aortic and pulmonary valves
open. When the ventricular septal defect is small, it produces a high-pitched murmur, heard along
the sternal border, and a normal second heart sound without a change in its normal physiologic
splitting.

American Board of Pediatrics Content Specification:


       Recognize the major clinical findings in patients with cardiac anomalies such as ventricular septal
        defect, atrial septal defect, patent ductus arteriosus, aortic stenosis, or pulmonic stenosis


23) 133 from 2009 answer B


The patient described in the vignette has history and physical examination findings that are highly
suggestive of infective endocarditis. These include symptoms of chills and malaise; a history of
fever; and the findings of hematuria, a new murmur, and fever. Typically, the diagnosis is
confirmed by isolation of the offending organism from blood cultures. Blood cultures from three to
five sites should be obtained prior to initiation of antibiotic therapy. Because the bacterial shedding
is constant, the practitioner should not wait until the patient is febrile to obtain blood cultures.
Viridans streptococci (eg, S bovis, S mitis) as well as Staphylococcus aureus are the most common
bacterial pathogens causing endocarditis in children. However, clinicians must be concerned about
organisms such as Enterococcus, coagulase-negative Staphylococcus, fungi, and a group of bacteria
referred to as the HACEK organisms (Haemophilus sp, Actinobacillus actinomycetemcomitans,
Cardiobacterium hominis, Eikenella corrodens, and Kingella kingae). The HACEK organisms are
gram-negative oral and pharyngeal flora that are fastidious and slow-growing, often requiring
growth factors and carbon dioxide to be isolated in cultures.

Treatment of endocarditis depends on the isolated organism. In general, long-term antibiotic
treatment (4 to 6 weeks) is undertaken in an effort to eradicate completely the bacteria that have
been sequestered in a nonvascular vegetation. Surgery is reserved for patients who develop severe
congestive heart failure from severe valve regurgitation or deterioration.

The boy in the vignette requires intravenous antibiotic treatment, but blood cultures should be
obtained before therapy is begun. He also should undergo echocardiography, which may be
performed from the transesophageal approach to improve the sensitivity, but similar to renal
ultrasonography, such a study is performed after blood cultures have been obtained. The absence of
vegetation at the time of echocardiography does not rule out a diagnosis of infective endocarditis.
Patients who have infective endocarditis may exhibit hematuria from the deposition of immune
complexes resulting in glomerulonephritis. Although fever and hematuria may be associated with
urinary tract infection, the presence of a diastolic murmur and absence of urinary symptoms make
such a diagnosis unlikely.

American Board of Pediatrics Content Specifications:


       Know the management of infective endocarditis
       Know the microbiology of infective endocarditis

				
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