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									Target PG - TNPG Self Assessment and Review
Author : Dr.J.Mariano Anto Bruno Mascarenhas
Question Stem
81) Vital layer of Hydatid Cyst is
Choices given
    A) Outer laminated
    B) Germinal Layer
    C) Gemule
    D) Brood Capsule
B) Germinal layer
Panicker 5th Edition 153
Harrison 15th Edition Chapter 223
Question Analysis
 Based on Question Category Question Grade Question Type Books                              Target PG Opinion
 Fact         Subtle Point          PG Entrance       Straight forward Given in Panicker Needs Memory
Echinococcosis is the most prevalent, serious human cestode infection in the world yet it is a zoonosis. Two
species are responsible for two distinct clinical presentations, Echinococcus granulosus (cystic hydatid) and the
more malignant E. multilocularis (alveolar hydatid).
With cystic hydatidosis from E. granulosus infection, the established cyst undergoes internal budding of
daughter cysts that remain contained within the larger primary structure. The host surrounds this cyst with a
tough, fibrous capsule. The primary cyst also produces a thick lamellar layer that supports a thin germinal layer
of cells responsible for budding and production of thousands of juvenile-stage parasites (protoscolices) that
remain attached to the wall or are free in the cyst fluid. The germinal layer is thus responsible for asexual
reproduction and also secretes the hydatid fluid which fills the cyst. The fluid in a healthy cyst is clear and
watery. After medical treatment it may become thick and bile stained.
 The right lobe of the liver is the most common site for development of cysts.
Tit Bits
 Reproduction in E. multilocularis resembles a malignancy. The secondary reproductive units bud externally
        and are not confined within a single, well-defined structure. Further, the cyst tissues are poorly
        demarcated from those of the host. This makes these cysts unsuitable for surgical removal. The
        secondary cysts are also capable of distant metastatic spread. The growing cyst mass eventually replaces a
        significant portion of the liver and compromises adjacent tissues and structures.

Question Stem
82)    Which of the following has No Cystic stage
Choices given
    A) Trichomonas vaginalsis
    B) Entamoeba histolytica
    C) Dientamoeba fragilis
    D) Giardia lamblia
A) Trichomonas vaginalsis
C) Dientamoeba fragilis
Panicker 5th Edition Pages 29 and 37
Question Analysis
 Based on Question Category Question Grade Question Type Books             Target PG Opinion
 Fact      Subtle Point     PG Entrance    Two choices   Given in Panicker Needs Memory

    A) Trichomonas vaginalis occurs only as trophozoite, there being no cystic form in Trichomonas
    B) Entamoeba histolytica produces a spherical cyst, about 10-15 m (micron) in size. The early cyst has
       single nucleus but the mature cyst is quadrinucleate
    C) Dientamoeba fragilis is the smallest of the intestinal amoeba, 5 to 8 m (micron) in size and is seen only
       rarely. It has two nucleus and the cytoplasm is fragile. It has no cystic phase and is non pathogenic
    D) Giardia lamblia encysts in the colon and the cyst is ovoid about 12 m (micron) by 8 m (micron) and
       surrounded by a tough hyaline cyst wall. The young cyst contains two and the mature cyst four nuclei
       situated at one end
 It is better to leave these kind of questions where it is very clear that we have two equally qualifying answers
       and cannot choose between the two
Tit Bits
 There are question in entrance exams where more than one answer can be correct and in those cases we
       have to choose the best, when we have more than one correct answer. But in this case, both choices are
       correct and we cannot choose one over another

Question Stem
83)     Treatment of Tropical Splenomegaly is
Choices given
     A) Chloroquine
     B) Proguanil
     C) Both
     D) None
C) Both
Harrison 15th Edition Chapter 214
Question Analysis
Based       Question Category         Question          Question Type Books                   Target PG
on                                    Grade                                                   Opinion
Concept Clinically Applied            PG Entrance       Straight           Given in           Needs Memory
            point                                       forward            Harrison
Tropical Splenomegaly (Hyperreactive Malarial Splenomegaly) Chronic or repeated malarial infections produce
hypergammaglobulinemia; normochromic, normocytic anemia; and, in certain situations, splenomegaly. Some
residents of malaria-endemic areas in tropical Africa and Asia exhibit an abnormal immunologic response to
repeated infections that is characterized by massive splenomegaly, hepatomegaly, marked elevations in serum
titers of IgM and malarial antibody, hepatic sinusoidal lymphocytosis, and (in Africa) peripheral B cell
lymphocytosis. This syndrome has been associated with the production of cytotoxic IgM antibodies to
suppressor (CD8+) lymphocytes, antibodies to CD5+ T cells, and an increase in the ratio of CD4+ T cells to
CD8+ T cells. It is believed that these events lead to uninhibited B cell production of IgM and the formation of
cryoglobulins (IgM aggregates and immune complexes). This immunologic process stimulates reticuloendothelial
hyperplasia and clearance activity and eventually produces splenomegaly. Patients with hyperreactive malarial
splenomegaly (HMS) present with an abdominal mass or a dragging sensation in the abdomen and occasional
sharp abdominal pains suggesting perisplenitis. Anemia and some degree of pancytopenia are usually evident,
but in many cases malarial parasites cannot be found in peripheral blood smears. Vulnerability to respiratory and
skin infections is increased; many patients die of overwhelming sepsis. Persons with HMS who are living in
endemic areas should receive antimalarial chemoprophylaxis: the results are usually good. In nonendemic areas,
treatment is advised. In some cases refractory to therapy, clonal lymphoproliferation may develop and then
evolve into a malignant lymphoproliferative disorder.
 Antimalarial drugs are effective therapy for HMS, and the specific choice of drug is dictated by the pattern
       and prevalence of drug resistance in that geographic area. The treatment should be continued regularly
       for a prolonged period to be effective. Months may pass before response is noticed, and relapses may
       occur when therapy is discontinued.
 No documented studies address the duration of adequate treatment, and no studies compare the different
       antimalarial medications. The role of lifelong prophylaxis for individuals residing in endemic areas is also
       not clear. Treatment may have to be continued for more than a year, sometimes even longer. Response
       to therapy is guided by the splenic size, decrease in serum IgM levels, improvement of anemia, and
       general improvement in the well-being of the patient. Chloroquine and proguanil appear to be equally
       effective, which suggests that the eradication of parasitemia is the common pathway responsible for the
       response. Pyrimethamine may be an alternative drug. Available data are lacking or limited regarding
       usefulness of other antimalarial drugs in HMS.
 The spleen is more commonly enlarged in vivax than in falciparum infections; perisplenitis, infarction, and
       even rupture may occur, and after repeated attacks the spleen may become very large and hard. Tropical
       splenomegaly syndrome ("hyper-reactive malarial splenomegaly") may constitute an abnormal immune
       response in malnourished children in developing countries. Enlargement of the spleen, without
       diminution following antimalarial treatment, is accompanied by lymphocytic infiltration of liver sinusoids
       and an elevated fluorescent antibody titer for malaria, with or without scanty parasitemia.
Tit Bits
 Pyrimethamine and sulfadoxine (Fansidar) -- Combination product containing sulfadoxine 500 mg and 25
       mg pyrimethamine. Pyrimethamine mechanism of action is the same as proguanil (ie, inhibits
       dihydrofolate reductase). Pyrimethamine therapy, perhaps for a shorter duration, may be effective in
       rapidly decreasing the size of spleen. Sulfonamides act in synergy with pyrimethamine and are used
       together. Administer with folinic acid to decrease its adverse effects.

Question Stem
84)    Virulence of Pneumococci is due to
Choices given
    A) Capsular Polysacchride
    B) Nuceloprotein
    C) Carbohydrate antigen
    D) All of the above
A) Capsular Polysacchride
Ananthanarayanan 7th Edition Page 218
Park 17th edition Page
Harrison 15th Edition Chapter
Question Analysis
Based       Question          Question           Question Type Books                            Target PG
on          Category          Grade                                                             Opinion
Concept Basic point           MBBS               Straight          Given in                     Needs Memory
                                                 forward           Ananthanarayanan
The most important antigen of the pneumococcus is the type specific capsular polysaccharide. As this
polysaccharide diffuses into the culture medium or infective exudates and tissue, it is also called the „specific
soluble substance (SSS)‟. Pneumococci are classified into types based on the antigenic nature of the capsular
    A) The virulence of the pneumocci depends on its capsule and the production of a toxin called
        pneumolysin. The Capsular Polysacchride because of its acidic and hydrophilic properties protects the
        cocci from phagocytosis. Capsulatted pneumococci are not effectively phagocytosed efficiently in fluid
        media or exudates. They are, however, susceptible to „surface phagocytosis‟, being engulfed against a
        firm surface, such as fibrin clot or epithelium
   B) Nuceloprotein is an antigen situated deep inside the cell and is species specific
   C) Somatic „C‟ Carbohydrate antigen is species specific

 Pneumococci produce an oxygen labile hemolysin and a leucocidin, but these are weak and make no
       contribution to virulence
Tit Bits
 The pneumococci are typed by
          o Agglutination with type specific antiserum
          o Precipitation of the SSS with Specific serum
          o Capsule Swelling reaction described by Neufeld called the Quellung reaction

Question Stem
85)    Chronic Granulomatous disease is a
Choices given
    A) B Cell Defect
    B) T Cell defect
    C) Complemet defect
    D) Disorder of Phagocytosis
D) Disorder of Phagocytosis
Ananthanarayanan 7th Edition Page 153
Question Analysis
Based     Question           Question           Question Type Books                          Target PG
on        Category           Grade                                                           Opinion
Concept Subtle Point         PG Entrance        Straight          Given in                   Needs Memory
                                                forward           Ananthanarayanan
Primary Immunodeficiency syndromes can be classified into
    A) Disorders of Specific Immunity
           1. Humoral
    B) Disorders of Complement
    C) Disorders of Phagocytosis
 Chronic granulomatous disease (CGD) is the most common of the inherited disorders of phagocyte
       function. The pivotal role of the respiratory burst (which follows within seconds after phagocytes are
       activated) in the subsequent effective killing of catalase-positive microbes became evident from studies
       of patients with CGD. The NADPH oxidase that catalyzes the respiratory burst is found exclusively in
       phagocytes and remains dormant unless activated by a variety of particulate and soluble stimuli, such as
       opsonized microbes and chemotactic peptides. These stimuli excite a transmembrane electron transport
       system in which NADPH on the cytoplasmic side of the membrane reduces oxygen through a series of
       reactions involving flavin adenine dinucleotide (FAD), several soluble cofactors, and membrane-
       associated cytochrome b. Oxygen is reduced through a univalent reduction to superoxide anion and is
       rapidly mutated to hydrogen perioxide and hydroxyl radicals. The latter two products are thought to be
       the principal means by which microbial killing or tissue damage takes place. Of the components of the
       phagocyte NADPH oxidase complex, the membrane components, a hemoprotein heterodimer with
       subunits of 91 kD and 22 kD, require at least two cytosolic protein components of 47 kD and 67 kD to
       achieve maximal oxidase activity. The X-linked and autosomally inherited forms of the disease are
       associated with missing components or subunits. The CGD gene is located on the X chromosome
       proximal to the muscular dystrophy gene and distal to the ornithine transcarbamylase gene on the Xp21
       band. The protein encoded by the X-CGD gene is synonymous with the 91-kD subunit of the
       cytochrome b complex. A reservoir of cytochrome b (~80-90%) is found in neutrophil-specific granules
       and is translocated to the membrane on activation of the cell. The 22-kD membrane subunit also has
       been cloned.
 Further Classification of the Primary Immunodeficiency syndromes
    A) Disorders of Specific Immunity
          1. Humoral Immunodeficiencies (B Cell defects)
                    a) X linked agammaglobulinemia
                    b) Transient hypogammaglobulinemia of infancy
                    c) Common variable immunodeficiency (late onset hypogammaglobulinemia)
                    d) Selective immunoglobulin deficiencies (IgA, IgM or IgG subclasses)
                    e) Immunodeficiencies with hyper IgM
                    f) Transcobalamin II deficiency
          2. Cellular immunodeficiencies (T Cell defects)
                    a) Thymic hyperplasia
                    b) Chronic mucocutaneous candidiasis
                    c) Purin nucleoside phosphorylase (PNP) deficiency
          3. Combined Immunodeficeincies (B and T Cell defects)
                    a) Cellular immunodeficiency with abnormal immunoglobulin synthesis (Nezelof‟s
                    b) Ataxia telangiectasia
                    c) Wiskott - Aldrich Syndrome
                    d) Immunodeficiency with thymoma
                    e) Immunodeficiency with short limbed dwarfism
                    f) Episodic lymphopenia with lymphocytotoxin
                    g) Severe combined immunodeficiency
                           1. „Swiss type‟ agammaglobulinemia
                           2. Reticular dysgenesis of de Vaal
                           3. Adenosis deaminase (ADA) deficiency
    B) Disorders of Complement
          1. Complement Component disorder
          2. Complement Inhibitor disorder
    C) Disorders of Phagocytosis
          1. Chronic granulomatous disorder
          2. Myeloperoxidase deficiency
          3. Chediak – Higashi Syndrome
          4. Leucocyte G6PD deficiency
          5. Job‟s Syndrome
          6. Tuftsin deficiency
          7. Lazy leucocyte syndrome
          8. Hyper – IgE Syndrome
          9. Actin-bionding protein deficiency
          10. Shwachman‟s disease
Tit Bits
 In Chronic granulomatous disease (CGD), chronic or recurrent pneumonia with unusual microbes, for
       example, Serratia marcescens, occurs frequently.

Question Stem
86)    Infection with which of the following does not confer natural active immunity
Choices given
    A) Chicken Pox
    B) Measles
    C) Hemophilus ducreyi
    D) Polio
C) Hemophilus ducreyi
Ananthanarayanan 7th Edition Page 76
Question Analysis
Based      Question           Question         Question Type Books                     Target PG
on         Category           Grade                                                           Opinion
Concept    Basic point        MBBS              Straight         Given in                     Needs Memory
                                                forward          Ananthanarayanan
Immunity can be classified as
 Innate (Native) Immunity
           o Nonspecific
                    Species
                    Racial
                    Individual
           o Specific
                    Species specific
                    Racial
                    Individual
 Acquired (Adaptive) Immunity
           o Active
                    Natural – following clinical or inapparent infection
                    Artificial – following vaccinations
           o Passive
                    Natural - resistance passively transferred from mother to baby in utero
                    Artificial – by administration of antibodies
    A) Infection with Chicken Pox confers natural active immunity
    B) Infection with Measles confers natural active immunity
    C) In chancroid, a venereal disease caused by Hemophilus ducreyi, there does not appear to be any effective
       immunity as the patient may develop lesions following reinfection even while the original infection is
    D) Infection with Polio confers natural active immunity
 In syphilis, a special type of immunity known as „premunition‟ is seen. Here the immunity to reinfection lasts
       only as long as the original infection remains active
Tit Bits
 Influenza canb recur in an individual after a few months or a year but this is not so much due to lack of the
       immunizing capacity of the virus as to its ability to undergo antigenic variation so that immunity
       following the first infection is not effective against the second infection caused buy an antigenically
       novel virus

Question Stem
87)     Gas Gangrene is caused by
Choices given
    A) Clostridium perfringens
    B) Clostridium tetani
    C) Clostridium botulinum
    D) Clostridium difficile
A) Clostridium perfringens
Ananthanarayanan 7th Edition Page 251
Question Analysis
Based       Question           Question        Question Type     Books                        Target PG
on          Category           Grade                                                          Opinion
Fact        Basic point        MBBS            Straight          Given in                     Needs Memory
                                               forward           Ananthanarayanan
The clostridia which are human pathogens are
   A) The gas gangrene group
            a. Established pathogens
                     i. Cl. perfringens
                    ii. Cl. septicum
                   iii. Cl. novyi
            b. Less pathogenic
                     i. Cl. histolyticum
                    ii. Cl. fallax
            c. Doubtful pathogens
                     i. Cl. bifermentans
                    ii. Cl. sporogenes
    B) Causing Tetanus
                     i. Cl. tetani
    C) Causing Food Poisoning
            a. Gastroenteritis
                     i. Cl. Perfringens (Type A)
            b. Necrotising enteritis
                     i. Cl. Perfringens (Type C)
            c. Botulism
                     i. Cl. botulinum
    D) Causing Acute Colitis
                     i. Cl. difficile
C. perfringens is the most common of the clostridial species isolated from tissue infections and bacteremias;
next in frequency are C. novyi and C. septicum
 Morphological and Biochemical classification of Clostridia

                                                                        Proteolytic or Saccharolytic
       Position of the           Both Proteolytic and Saccharolytic          Slightly Proteolytic
                                                                                                      Saccharolytic but    Neither Proteolytic
       spore                     Proteolytic            Saccharolytic               but not
                                                                                                        not Proteolytic    nor Saccharolytic
                               predominating            predominating           Saccharolytic
       Central or          Cl. bifermentans         Cl. perfringens         -                        Cl. fallax            -
       subterminal         Cl. botulinum A,B,F      Cl. septicum                                     Cl. botulinum C,D,E
                           Cl. histolyticum         Cl. chauvoei
                           Cl. sordelli             Cl. novyi
                           Cl. sporogens
       Oval and terminal   -                        Cl. difficile           -                       Cl. tertium            Cl. cochlearum
       Spherical and       -                        -                       Cl. tetani              Cl. tetanomorphum      -
       terminal                                                                                     Cl. sphenoides

Tit Bits
 Clostridium novyi is also called as clostridioum edematiens

Question Stem
88)    Food poisoning is caused by all except
Choices given
    A) Bacillus cerues
    B) Proteus
    C) Staphyloccocus
    D) Salmonella
B) Proteus
Ananthanarayanan 7th Edition Page 246, 196, 303
Question Analysis
Based      Question Category Question                            Question                 Books                                  Target PG
on                              Grade                            Type                                                            Opinion
Concept Clinically Applied      MBBS                             Straight                 Given in                               Needs Memory
           point                                                 forward                  Ananthanarayanan
Facts about Bacterial Food Poisoning

Incubation Period,
Organisms                   Symptoms                           Common Food Sources
1 TO 6 H
Staphylococcus aureus       Nausea, vomiting, diarrhea         Ham, poultry, potato or egg salad, mayonnaise,
                                                                cream pastries
Bacillus cereus             Nausea, vomiting, diarrhea         Fried rice
8 TO 16 H
Clostridium perfringens     Abdominal cramps, diarrhea         Beef, poultry, legumes, gravies
                             (vomiting rare)
B. cereus                   Abdominal cramps, diarrhea         Meats, vegetables, dried beans, cereals
                             (vomiting rare)
> 16 H
Vibrio cholerae           Watery diarrhea                      Shellfish
Enterotoxigenic           Watery diarrhea                      Salads, cheese, meats, water
 Escherichia coli
Enterohemorrhagic E. coli Bloody diarrhea                      Ground beef, roast beef, salami, raw milk, raw
                                                                vegetables, apple juice
Salmonella spp.             Inflammatory diarrhea              Beef, poultry, eggs, dairy products
Shigella spp.               Dysentery                          Potato or egg salad, lettuce, raw vegetables
Vibrio parahaemolyticus     Dysentery                          Mollusks, crustaceans

    A) Bacillus cerues produces two patterns of food borne disease. – the diarrhoeal disease caused by serotypes
        2,6,8,9,10 or 12 and the rice associated emetic illness is caused by serotypes 1, 3 or 5
    B) Proteus is not a common cause of Food Poisoning
    C) Enterotoxin is responsible for the food poisoning with Staphyloccocus
    D) Salmonella gastroenteritis (more appropriately enterocolitis) or food poisoning is generally a zoonotic
Several clinical syndromes follow the ingestion of contaminated food or water
 Nausea and vomiting within 6 hr
             o Toxins that produce direct gastric irritation,
                      Such as heavy metals, or with
             o Preformed toxins of
                      B. cereus (B. cereus also produces an enterotoxin )or
                      S. aureus;;
 Paresthesia within 6 hr; Paresthesias after a brief incubation period are suggestive of
             o scombroid (histamine fish poisoning),
             o paralytic or neurotoxic shellfish poisoning,
             o Chinese restaurant syndrome (monosodium glutamate poisoning),
             o niacin poisoning, or
             o ciguatera fish poisoning
 Neurologic and gastrointestinal symptoms within 2 hr;
             o ingestion of toxic mushrooms
                      parasympathetic hyperactivity,
                      confusion,
                      visual disturbances,
                      and hallucinations to
                      hepatic or
                      hepatorenal failure, which occurs after a 6-24 hr incubation period.
 Abdominal cramps and watery diarrhea within 16-48 hr;
             o 8-16 hr incubation period
                      enterotoxin-producing Clostridium perfringens and
                   B. cereus.
 Fever, abdominal cramps, and diarrhea within 16-72 hr;
          o Salmonella,
          o Shigella,
          o C. jejuni,
          o Y. enterocolitica, and
          o enteroinvasive E. coli are associated with diarrhea, which may contain fecal leukocytes,
              abdominal cramps, and fever, although these organisms can cause watery diarrhea without fever.
 Abdominal cramps, bloody diarrhea without fever within 72-120 hr;
          o enterohemorrhagic E. coli, such as E. coli 0157:H7.
 Hemolytic uremic syndrome
          o enterohemorrhagic E. coli.
 Neurologic signs and symptoms within 6-24 hr; and nausea, vomiting, and paralysis within 18-48 hr
          o blurred vision,
          o dry mouth,
          o dysarthria,
          o diplopia, or
          o descending paralysis
       should suggest C. botulinum as the cause
Tit Bits
 Not all food poisoning has a bacterial cause. Diagnostic confusion can result from diarrhea caused by
       nonbacterial agents of short-incubation food poisoning, including capsaicin, which is found in hot
       peppers, and a variety of toxins found in fish and shellfish

Question Stem
89)    Mycelia are
Choices given
    A) Unicellular growth form of fungi
    B) Thread like branching cylindrical tubules
    C) Clumps of intertwined branching hyphae
    D) Reproducing bodies of molds
C) Clumps of intertwined hyphae
Ananthanarayanan 7th Edition Page 610
Question Analysis
Based      Question           Question          Question Type Books                          Target PG
on         Category           Grade                                                          Opinion
Concept Basic point           High School       Straight        Given in                     Needs Memory
                                                forward         Ananthannarayanan
Fungi are eukaryotic cells, which lack chlorophyll, and they cannot generate energy through photosynthesis.
They do not require aerobic environment
    A) Yeast is the unicellular growth form of fungi. These cells can appear spherical to ellipsoidal. Yeast
       reproduce by budding. When buds do not separate, they can form long chains of yeast cells, which are
       called pseudohyphae. Yeast reproduce at a slower rate than bacteria
    B) Hyphae are threadlike, branching, cylindrical tubules composed of fungal cells attached end to end.
       These grow by extending in length from the tips of the tubules
    C) Molds (also called as mycelia) are composed of clumps of intertwined tangled mass of branching hyphae.
       These grow by longitudinal extension and produce spores
    D) Spores are reproducing bodies of molds. Spores are rarely seen in skin scrapings
 All Candida species pathogenic for humans are also encountered as commensals of humans, particularly in
       the mouth, stool, and vagina. These species grow rapidly at 25° to 37°C on simple media as oval,
       budding cells. In special culture media and in tissue, hyphae or elongated branching structures called
       pseudohyphae are formed. C. glabrata differs from other members of the genus in that it forms no true
       hyphae or pseudohyphae in vitro or in infected tissue.
 Demonstration of pseudohyphae on wet smear with confirmation by culture is the procedure of choice for
       diagnosing superficial candidiasis
Tit Bits
 Candida yeast cells and pseudohyphae are the only fungi that are usually gram-positive on smears

Question Stem
90)    Erythema Chronicum Migrans is
Lyme‟s Disease
Ananthanarayanan 6th Edition Page 389
Harrison 15th Edition Page 1062
 Refer to Question 97 in TNPG 2002 Section for more information and relevant discussions

Question Stem
91)    Cat are associated with all except
Choices given
    A) Bartonella quintana
    B) Toxoplasma gondii
    C) Pasteurella multocida,
    D) Tularemia
A) Bartonella quintana
Harrison 14th Edition Chapter 163
Question Analysis
Based      Question              Question            Question Type      Books                    Target PG
on         Category              Grade                                                           Opinion
Concept Basic point              MBBS                Straight           Given in Most            Needs Memory
                                                     forward            books

 Although less common than dog bites, cat bites and scratches result in infection in more than half of all
       cases. Because the narrow, sharp feline incisors penetrate deeply into tissue, cat bites are more likely than
       dog bites to cause septic arthritis and osteomyelitis; the development of these conditions is particularly
       likely when punctures are located over or near a joint, especially in the hand. Women sustain cat bites
       more frequently than do men. These bites most often involve the hands and arms. Both bites and
       scratches from cats are prone to infection from organisms in the cat's oropharynx. Pasteurella multocida,
       a normal component of the feline oral flora, is a small gram-negative coccobacillus implicated in the
       majority of cat-bite wound infections. Like that of dog-bite wound infections, however, the microflora
       of cat-bite wound infections is usually mixed. Other microorganisms causing infection after cat bites are
       similar to those causing dog-bite wound infections.
    A) Typical Cat Scratch Disease (CSD) is manifested by painful regional lymphadenopathy persisting for
       several weeks or months after a cat scratch. Occasionally, infection may disseminate and produce more
       generalized lymphadenopathy and systemic manifestations, which may be confused with the
       manifestations of lymphoma. Bartonella henselae is the causative agent of CSD. There is no
       evidence that B. quintana causes CSD, and this microbe is not carried by cats. The role of Afipia
       felis (originally proposed as the agent of CSD) is unclear inasmuch as only a few cases are associated
       with its isolation. B. henselae remains the predominant species causing typical CSD. Several reports
       suggest that B. clarridgeiae may also cause feline lymphadenopathy
    B) The principal stage in the life cycle of the parasite T.gondii takes place in the cat (the definitive host) and
       its prey.
    C) Pasteurella multocida, a normal component of the feline oral flora, is a small gram-negative coccobacillus
       implicated in the majority of cat-bite wound infections.
    D) Tularemia has also been reported to follow cat bites
 The same risk factors for systemic infection following dog-bite wounds apply to cat-bite wounds. Pasteurella
       infections tend to advance rapidly, often within hours, causing severe inflammation accompanied by
       purulent drainage; Pasteurella may also be spread by respiratory droplets from animals, resulting in
       pneumonia or bacteremia. Like dog-bite wounds, cat-bite wounds may result in the transmission of
       rabies or in the development of tetanus.
Tit Bits
 Puncture wounds due to cat bites should be left unsutured because of the high rate at which they become
       infected. Facial wounds are usually sutured after thorough cleaning and irrigation because of the
       importance of a good cosmetic result in this area and because anatomic factors such as an excellent
       blood supply and the absence of dependent edema lessen the risk of infection.

Question Stem
92)     Example of Dimorphic Fungi is - Histoplasma
Choices given
    A) Cryptococcus
    B) Candida
    C) Trichophyton
    D) Histoplasmosis
D) Histoplasmosis
Ananthanarayanan 7th Edition Page 611
Park 17th edition Page
Harrison 15th Edition Chapter
Question Analysis
 Based on Question Category Question Grade Question Type Books                                Target PG Opinion
 Concept Basic point               MBBS              Straight forward Given in all books Needs Memory
Fungi are classified as eukaryotic microorganisms, in contrast to bacteria, which are considered prokaryotic.
Eukaryotes, such as fungi, possess a discrete nuclear membrane and a nucleus that contains several
chromosomes, whereas prokaryotes have no nucleus or nuclear membrane and possess only a single
chromosome. Fungi also differ from bacteria in the ability of the former to reproduce sexually or asexually.
Most fungi reproduce by asexual spore formation. When sexual mating of two closely related species, e.g.,
Cryptococcus neoformans, serotypes A and D, takes place, the "perfect state" (Filobasidiella neoformans var.
neoformans) is produced. Fungi for which a perfect state has not been identified are referred to as fungi
imperfecti (e.g., Candida albicans and Coccidioides immitis). The cell walls of fungi are rigid, usually composed
of chitin, glucan, and mannoproteins, another feature that distinguishes fungi from bacteria. In addition, the
cytoplasmic membrane of fungi contains sterols, (principally ergosterol) which are the target sites of action for
the major classes of antifungal drugs.
    A) Yeasts are unicellular fungi which occur as spherical or ellipsoidal cells and reproduce byt simple
        budding. On culture they form smooth creamy colonies. The only pathogenic yeast is Cryptococcus
    B) Yeast like fungi grow partly as yeast and partly as elongated cells resembling hyphae. The latter forms
        pseudomycelium. Candida albicans is a pathogenic yeast like fungus
    C) Moulds or Filamentous fungi form true mycelia and reproduce by the formation of different types of
        spores Dermatophytes are examples of pathogenic moulds
    D) Dimorphic fungi can occur as filaments or as yeasts depending on the conditions of growth. In host
        tissues or cultures at 37oC they occur as yeasts, while in the soil and in cultures at 22oC they appear as
        moulds. Most fungi causing systemic infections are dimorphic fungi.
Histoplasma capsulatum is a dimorphic fungus that grows as a mold in nature or on Sabouraud's agar at room
temperature. Hyphae bear both large and small spores, which are used for identification. Nucleic acid
hybridization can also be used to identify the organism in culture. H. capsulatum grows as a small budding yeast
in host tissue and on enriched agar, such as blood cysteine glucose, at 37°C. Despite its name, the fungus is
unencapsulated. Coculture of isolates with opposite mating types can produce different sporulating structures in
which genetic recombination occurs. When these structures, referred to as a teleomorph or the perfect state, are
seen in culture, the name Ajellomyces capsulatus is used
Tit Bits about Classification of Fungi
Fungi can be classified based on
 Cell morphology – into Yeasts, yeast like fungi, moulds and dimorphic fungi
 On the basis of sexual spore formation
            o Phycomycetes
                      Lower fungi
                      Non septate hyphae
                      Form endogenous asexual spores called sporangiospores contained within swollen sac
                        like structures called sporangia
                      They also produce sexual spores known as oospores in some fungi and zygospores in
                        some others
            o Ascomycetes
                      Higher fungi
                      Septate hyphae
                      Form exogenous spores called conidia
                      Form asexual spores (ascospores) within a sac or ascus
                      Include both yeasts and filamentous fungi
            o Basidomycetes
                      Higher fungi
                      Septate hyphae
                      Form exogenous spores called conidia
                      Form sexual spores (basidiospores) on a „basidium‟ or base
            o Deuteromycets or hyphomycetes (Fungi imperfecti)
                      Provisional group consisting of fungi whose Sexual phases have not been identified
                      Higher fungi
                      Septate hyphae
                      Form exogenous spores called conidia

Question Stem
93)     H.Pyloric is Carcinogenic due to
Choices given
    A) CagA gene
    B) VacA gene
    C) Its ability to convert nitrates
    D) All of the above
D) All of the above
Ananthanarayanan 7th Edition Page 408
Question Analysis
 Based on Question Category Question Grade Question Type Books                              Target PG Opinion
 Concept Basic point                MBBS            Straight forward Given in all books Needs Memory
The disease causing strains of Helicobacter pylori contain a “pathogenicity island” containing the CagA
(cytotoxin associated gene A) and a secretory system which injects the CagA protein into the host cells. Another
gene associated with virulence is is VacA, which encodes a vacuolating toxin that causes apoptosis
Infection with H. pylori is associated with gastric adenocarcinomas of the intestinal through a sequence that
involves chronic gastritis, multifocal atrophy with lower gastric acid secretion, intestinal metaplasia, dysplasia and
Remarks about the diagnostic tests for H.pylori

                     Commonly Used Tests to Detect Helicobacter pylori Infection
Test               Advantages                 Disadvantages             Remarks
Biopsy urease test Quick, simple              Rapid test not fully
                                               sensitive, 24-h test not
                                               fully specific
Histology          Widely available; may give Sensitivity dependent on Examination by microscopy
                    additional histologic      experience                  Silver Staining
                    information                                            Gram Staining

Culture              Permits determination of        Sensitivity dependent on
                      antibiotic susceptibilities     experience
Serology (ELISA) Cheap and convenient                Cannot be used for early
13C or 14C urea           Safer and cheaper             Need Isotope            The subject drinks a urea solution
 breath test                   than endoscopy                   assay             containing labeled carbon which
 (Breath Urease           Sensitive                            facilities        can be detected in the breath.
 Test)                    Reliable                      Low-dose
                                                                irradiation in
                                                                14C test

Tit Bits about Nitrate-Converting Bacteria as a Factor in the Causation of Gastric Carcinomaa
     Exogenous sources of nitrate-converting bacteria:
           o Bacterially contaminated food
                   common in lower socioeconomic classes, who have a higher incidence of the disease;
                   diminished by improved food preservation and refrigeration
           o ? Helicobacter pylori infection
     Endogenous factors favoring growth of nitrate-converting bacteria in the stomach:
           o Decreased gastric acidity
           o Prior gastric surgery (antrectomy) (15 to 20 year latency period)
           o Atrophic gastritis and/or pernicious anemia
           o ? Prolonged exposure to histamine H2-receptor antagonists

Question Stem
94)    The correct statement about Infectious Mononucleosis is
Choices given
    A) Caused by Cytomegalovirus
    B) The virus belongs to the alpha sub family
    C) Caused by Salivary gland Viruses
    D) Also called as Kissing Disease
D) Also called as Kissing Disease
Ananthanarayanan 7th Edition Page 483
Question Analysis
Based      Question            Question         Question       Books                              Target PG
on         Category            Grade            Type                                              Opinion
Concept Subtle Point           PG Entrance      Trap           Given in                           Needs Memory
                                   Classification of Human Herpes Viruses
                            Species                                              Site of latent
                                                        Sub family Cytopathology
     Official name             Common Name                                       infection
     Human Herpes Virus Type 1   Herpes simplex Virus type 1       Alpha        Cytolytic             Neurons
     Human Herpes Virus Type 2   Herpes simplex Virus type 2       Alpha        Cytolytic             Neurons
     Human Herpes Virus Type 3   Varicella Zoster Virus            Alpha        Cytolytic             Neurons
     Human Herpes Virus Type 4   Epstein Barr Virus                Gamma        Lymphoproliferative   Lymphoid
     Human Herpes Virus Type 5   Cytomegalovirus                   Beta         Cytomegalic           Secretory, Glands,
                                                                                                      Kidneys,        other
                                                                                                      organs and tissues
     Human Herpes Virus Type 6   Human B cell lymphotropic virus   Beta         Lymphoproliferative   Lymphoid tissues
     Human Herpes Virus Type 7   RK Virus                          Beta         Lymphoproliferative   Lymphoid tissues
     Human Herpes Virus Type 8   Kaposi Sarcoma associated         Gamma
                                 herpesvirus (KSHV)

    A) Infectious mononucleosis is Caused by Epstein Barr Virus
    B) The virus belongs to the gamma sub family
    C) Cytomegaloviruses are called as Caused by Salivary gland Viruses
    D) Infectious mononucleosis is also called as Kissing Disease and also as Glandular Fever
 Epstein Barr Virus (EBV) infection may lead to one of the following
           o Infectious mononucleosis
           o EBV associated malignancies
                   Burkitt‟s Lymphoma
                   Lymphomas in immunodeficient persons such as AIDS patients and transplant recipients
                   Nasopharyngeal carcinoma in persons of Chinese origin
Tit Bits
 Darling‟s Disease is Histoplasmosis

Question Stem
95)    Paul Bunnel Test is used to detect Infectious mononucleosis caused by
Choices given
    A) Cytomegaloviruses
    B) Epstein Barr Virus
    C) Toxoplasmosis
    D) All of the above
B) Epstein Barr Virus
Ananthanarayanan 7th Edition Page 485
Question Analysis
Based      Question            Question          Question          Books                    Target PG
on         Category            Grade             Type                                       Opinion
Concept Subtle Point           PG Entrance       Trap              Given in                 Needs Memory
 Infectious mononucleosis is an acute self limiting illness usually seen in non immune young adults following
       primary infection with the EB Virus.
 The infectious mononucleosis syndrome can follow infection by other agents such as cytomegalovirus and
       toxoplasmosis or as a reaction to non infectious stimuli
The heterophile Paul – Bunnel test is positive only in disease caused by the EB Virus
 Heterophile antibodies agglutinate cells from species different from those in the source serum. The transient
     heterophile antibodies seen in infectious mononucleosis, also known as Paul-Bunnell antibodies, are IgM
     antibodies detected by the Paul-Bunnell-Davidsohn test for sheep red cell agglutination. The heterophile
     antibodies of infectious mononucleosis agglutinate sheep or, for greater sensitivity, horse red cells but
     not guinea pig kidney cells. This adsorption property differentiates this response from the heterophile
     response found in patients with serum sickness, rheumatic diseases, and some normal individuals. Titers
     greater than 1:28 or 1:40 (depending on the dilution system used) after absorption with guinea pig cells
     are considered positive.
                         Differential absorption test for Paul Bunnel Antibody
                                                     Result of Absorption by
                    Clinical Condition
                                                     Guinea Pig Kidney Ox Red Cells
                    Normal Serum                     Absorbed             Not absorbed
                    Antibody after serum therapy Absorbed                 Not absorbed
                    Infectious mononucleosis         Not absorbed         Absorbed

 The sheep red cell agglutination test is likely to be positive for several months after infectious
       mononucleosis; the horse red cell agglutination test may be positive for as long as 2 yr. The most widely
       used method is the qualitative, rapid slide test using horse erythrocytes. It detects heterophile antibody in
       90% of cases of EBV-associated infectious mononucleosis in older children and adults but in only up to
       50% of cases in children younger than 4 yr because they typically develop a lower titer. Approximately 5-
       10% of cases of infectious mononucleosis are not caused by EBV and are not uniformly associated with
       a heterophile antibody response. The false-positive rate is less than 10%, usually resulting from
       erroneous interpretation. If the heterophile test is negative and an EBV infection is suspected, EBV-
       specific antibody testing is indicated.
Tit Bits
 EBV-specific antibody testing is useful to confirm acute EBV infection, especially in heterophile-negative
       cases, or to confirm past infection and determine susceptibility to future infection. Several distinct EBV
       antigen systems have been characterized for diagnostic purposes. The EBNA, EA, and VCA antigen
       systems are most useful for diagnostic purposes.

Question Stem
96)    The antibody conferring Local Immunity is
Choices given
    A) IgA
    B) IgG
    C) IgM
    D) IgE
A) IgA
Ananthanarayanan 7th Edition Page 88
Question Analysis
 Based on Question Category Question Grade Question Type Books                             Target PG Opinion
 Concept Basic point               MBBS             Straight forward Given in all books Needs Memory
 Immunoglobulins constitute 20-25% of the total serum proteins. Based on physiochemical and antigenic
       differences, five classes of immunoglobulins have been recognized – IgG, IgA, IgM, IgD and IgE.
 Both Ig and  (gamma) are accepted abbreviations for immunoglobulins
 The constant domains of the heavy chain define the isotype of the antibody, IgG, A, D, M or E, each of
       which has particular functions.
 The isotypes determine essential properties of the antibodies, particularly binding of C1q of the complement
       system, binding of the Fc receptor that enables antibody to cross the placenta, and binding of Fc
       receptors on mast cells and basophils.
    A) IgA binds to a specific Fc receptor, known as a secretory component, which is on the epithelial
       membranes. The antibody can then be endocytosed and transported across these cells and released on
       the outside, that is the gut lumen, biliary tract, respiratory tract or milk duct. Light-chain constant regions
       are one of two classes, appa or ambda. There are no known differences in function between the two.
    B) An IgG molecule consists of four chains, two identical heavy chains (50 000 Da) and two identical
       light chains (25000 Da). The immunoglobulin molecule can be broken into segments by enzymes, giving
       the peptides. Sequence analysis of light and heavy chains and crystallographic studies have revealed that
       they are composed of domains of about 100 amino acids, held by a disulphide loop between two
       cysteines (a domain structure that has been found to be present in many other cell-surface molecules).
       There are two for each light chain (L) and four for an IgG amma heavy chain (H). The N-terminal
       domains of both L and H chains are highly variable when different antibody molecules are compared:
       they contain the antigen-binding site.
    C) IgM is phylogenetically the oldest Ig Class
    D) IgE is reagenic antibody
 IgD resembles IgG Structurally
Tit Bits
 Mnemonic for IgD is „3‟ – concentration of 3 mg per 100 ml of serum and half life of 3 days

Question Stem
97)    Rabies presents with
Negri bodies
 Refer Question Number 98 in TNPG 2002 Micro Section

Question Stem
98)    The most common agent associated with .neonatal bacterial meningitis is
Streptococcus agalactiae or Group B Streptococcus
 Refer to Question No 92 in TNPG 2002 Micro

Question Stem
99)    Bull‟s neck is characteristically seen in
Choices given
    A) Harmatoma of Lung
    B) Diphtheria
    C) Glaucoma
    D) Hepatic Candidiasis
B) Diphteria
Ananthanarayanan 7th Edition Page 234
Question Analysis
Based      Question              Question           Question Type       Books           Target PG Opinion
on         Category              Grade
Concept Basic point              High School        Straight            Given in        Needs Memory
                                 MBBS               forward             Park            Needs Analysis
                                 PG Entrance        Twisted                             Needs memory and
                                 Super specialty    Trap                                Analysis

 In the diphtheria, the primary focus of infection was the tonsils or pharynx in 94%, with the nose and larynx
      the next two most common sites. After an average incubation period of 2-4 days, local signs and
      symptoms of inflammation develop. Fever is rarely higher than 39ºC. Infection of the anterior nares
       (more common in infants) causes serosanguinous, purulent, erosive rhinitis with membrane formation.
       Shallow ulceration of the external nares and upper lip are characteristic. In tonsillar and pharyngeal
       diphtheria, sore throat is a universal early symptom, but only one half of patients have fever, and fewer
       have dysphagia, hoarseness, malaise, or headache. Mild pharyngeal injection is followed by unilateral or
       bilateral tonsillar membrane formation, which extends variably to affect the uvula, soft palate, posterior
       oropharynx, hypopharynx, and glottic areas.
 Underlying soft tissue edema and enlarged lymph nodes can cause a "bull-neck" appearance. The degree of
       local extension correlates directly with profound prostration, bull-neck appearance, and fatality from
       airway compromise or toxin-mediated complications.
 The leather-like adherent membrane, extension beyond the faucial area, relative lack of fever, and dysphagia
       help differentiate diphtheria from exudative pharyngitis due to Streptococcus pyogenes and Epstein-Barr
 Vincent angina, infective phlebitis and thrombosis of the jugular veins, and mucositis in patients undergoing
       cancer chemotherapy are usually differentiated by the clinical setting. Infection of the larynx, trachea,
       and bronchi can be primary or a secondary extension from the pharyngeal infection. Hoarseness, stridor,
       dyspnea, and "croupy" cough are clues. Differentiation from bacterial epiglottitis, severe viral
       laryngotracheobronchitis, and staphylococcal or streptococcal tracheitis hinges partially on the relative
       paucity of other signs and symptoms in the patient with diphtheria and primarily on visualization of the
       adherent pseudomembrane at the time of laryngobronchoscopy and intubation.
    A) In CT Scan of Lung while investigating a solitary puylm0nary nodule, “bull‟s eye” denotes granuloma
       and “popcorn ball” denotes hamartoma.
    B) Diphtheria presents with Bull Neck
    C) Glaucoma presents with Buphthalmos – Bull Eye
    D) Hepatic candidiasis results from seeding of the liver (usually from a gastrointestinal source) in
       neutropenic patients. It is most common in patients being treated for acute leukemia and usually
       develops around the time the neutropenia resolves. The characteristic picture is that of persistent fever
       unresponsive to antibiotics; abdominal pain and tenderness or nausea; and elevated serum levels of
       alkaline phosphatase in a patient with hematologic malignancy who has recently recovered from
       neutropenia. The diagnosis of this disease (which may present in an indolent manner and persist for
       several months) is based on the finding of yeasts or pseudohyphae in granulomatous lesions. Hepatic
       ultrasound or computed tomography (CT) may reveal bull's-eye lesions.
 Few more Animal Signs
                          Animal Comparison Sign                    Condition
                        Elephant Legs             Elephantiasis     Filariasis
                             Lion Face            Leonine Facies    Lepramatous Leprosy
                             Bull Heart           Cor Bovinum       Cardiomegaly
                            Wolf Face             Facies            Lupus Erythematosus
                            Goat Sound            Aegophony         Pneumonia
                          Sea gull Sound          Sea gull Murmur Aortic Regurgitation
                            Elfin Face            Elfin Facies      Aortic Stenosis
                             Fish Skin            Ichythyosis       Ichythyosis
                             Bull Eye             Buphthalmos       Glaucoma
                            Hare Eye              Lagophthalmos Lagophthalmos
                            Toad Skin             Phrynoderma       Phrynoderma
Tit Bits
 Do you know that the following medical terminologies originated from Animal Kingdom?

                    Animal / Bird        Terminology           Intepretation
                    Crab                 Cancer
                    Horse                Hippocampus           (Sea Horse)
                                         Cauda Equina          (Horse Tail)
                    Worm                 Lumbrical
                                         Vermis                (Cerebellum)
                    Snail                Cochlea
                    Cockle-shell         Chemosis              (resembling gaping shell)
                    Wolf                 Lupus                 (Wolf Facies in SLE)
                    Mouse                Muscle
                    Bull                 Buphthalmos           (Bull Eyed)
                    Hare                 Lagophthalmos         (Hare Eyed)
                    Fish                 Ichthyosis
                    Toad                 Phrynoderma           (Toad skin)
                    Ant                  Formification
                    Cuckoo               Coccyx
                    Crow                 Coronoid
                    Goose                Chenopodium           (Goose Feet – Mexican Tea)
                    Beak                 Rostrum               (Rostrum Sphenoidale)
                                         Rostral               (directed towards snout end)
                    Wing (Latin)         Ala                   (Crista Galli)
                                         Pinna                 (Ear)
                    Wing (Greek)         Pterion               (in Skull)
                                         Pterygium             (in Eye)
                                         Pterygoid             (Muscles)
                    Horse Stirrup        Stapes                (in Middle Ear)
                    Saddle               Sella                 (Tursica)

                    Spur on bird‟ s leg Calcar Avis        (Hippocampus Minor)
                    Calcar Femorale     (Bigelow‟s Septum)
                    Calcar Pedis                           (Heel)

Question Stem
100) Which of the following statement is true regarding adjuvants
Choices given
    A) Adjuvants decrease the efficacy of vaccines
    B) More antigens are needed when an adjuvant is added
    C) More antibodies are produced when an adjuvant is added
    D) More doses are needed when an adjuvant is added
C) More antibodies are produced when an adjuvant is added
Park 18th edition 97
Question Analysis
    Based on Question Category Question Grade Question Type Books                         Target PG Opinion
    Concept Basic point              MBBS               Straight forward Given in Park Needs Memory
The immune response to some antigens is potentiated by the addition of adjuvants such as aluminum salts or, in
the case of polysaccharides (e.g., the polyribose phosphate oligosaccharide of Hib), by conjugation to a carrier
protein. Adjuvants, nonspecific boosters of immune responses, are used with inactivated products such as
diphtheria and tetanus toxoids, acellular pertussis (aP) vaccine, and HBV vaccine. The mechanism for adjuvant
enhancement of immunogenicity is not well defined but relates in part to the rendering of soluble antigens into a
particulate form, the mobilization of phagocytes to the site of antigen deposition, and the slowing down of the
release of antigens, which prolongs stimulation of the immune response
    A) Adjuvants increase the efficacy of vaccines
    B) Less antigens are needed when an adjuvant is added
    C) More antibodies are produced when an adjuvant is added
  D) Less doses are needed when an adjuvant is added
 Most of the immunizing agents contain preservatives, stabilizers, antibiotics, adjuvants, and a suspending

            Component        Use and Examples
            Preservatives,   Constituents can inhibit or prevent bacterial growth or stabilizers,
                             antibiotics        stabilize the antigen. Materials such as mercurials
                             or antibiotics are used. Allergic reactions to any of the additives
                             may occur.
            Adjuvants        An aluminum salt is used in some vaccines to enhance the immune
                             response (e.g., toxoids, hepatitis B).
            Suspending fluid Sterile water, saline, or more complex fluids derived from the
                             growing media or biologic system in which the agent is produced
                             (e.g., egg antigens, cell culture ingredients, serum proteins) are used.
Tit Bits
 Examples of adjuvants are
         o Aluminium phosphide
         o Aluminium hydroxide
         o Water in Oil

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