AIIMS NOV 2016: Pathology

Q-1. For detection of pre-malignant lesion of lip, stain used
a) H&E
b) Giemsa
c) Crystal violet
d) Toluidine blue

Answer: Toluidine blue
Toluidine blue (TB) is an acidophilic dye designed to stain acidic cellular components such as DNA and RNA.
Its use in the detection of precancerous/cancerous tissue is based on the fact that dysplastic tissue contains quantitatively more DNA and RNA than non-dysplastic tissue.
Toluidine blue stain is used for early diagnosis of oropharyngeal carcinomas.

Q-2. A 20 years old patient having RBC count 2 lakhs/mm3, PCV 30 percent and Hb 9.3 g/dl, diagnosis is
a) Iron deficiency anemia
b) Thalassemia
c) Sideroblastic anemia
d) Folic acid deficiency anemia

Answer: Folic acid deficiency anemia
Mean corpuscular volume (MCV) = Hematocrit (%) X 10/RBC count (million/mm3)
Mean corpuscular hemoglobin concentration (MCHC) = Hemoglobin (g/ 100 ml) X 100/ hematocrit (%)
Important point:
MCV raised → Macrocytic anemia most often caused by Vitamin B12 deficiency and folic acid deficiency

Q-3. Injury to this area causes what kind of speech defect

a) Sensory aphasia
b) Speech apraxia
c) Aphonia
d) Dysarthria

Answer: Dysarthria
Central core of white matter of cerebellum being arranged in form of branching pattern of a tree is called arbor vitae cerebelli.
Ataxic dysarthria results from cerebellar lesions. Such damage could be caused by stroke, trauma or by neurological disorders like muscular sclerosis.

Q-4. Given below is the histopathology of liver biopsy of a patient with hemochromatosis. Which of the following stain is used?

a) Prussian blue
b) Alcian blue
c) Von kossa
d) Crystal violet

Answer: Prussian blue
Hepato-cellular iron deposition is blue in this Prussian blue stained section of an early stage of hemochromatosis in which parenchymal architecture is normal.

Q-5. Autopsy of heart of a patient died due to Myocardial infarction was stained with triphenyltetrazolium tetrachloride dye.
Color of normal part of heart will be seen as
a) Blue
b) White
c) Red
d) Dark Brown

Answer: Red
Myocardial infarcts less than 12 hours old are usually not apparent on gross examination.
It is often possible to highlight the area of the necrosis that first becomes apparent after 2-3 hours after the infarct, by the immersion of tissue slices in a solution of triphenyltetrazolium chloride.
This histo-chemical stain imports a brick red color to intact, non-infarcted myocardium where the dehydrogenase enzymes are preserved.

Q-6. 25 yr female presents in December month with chronic fatigue syndrome and Cyanosis with blue lips.
Image showed RBC clumps. Most likely cause is

a) Cold AIHA
b) Warm AIHA
c) Hemo-globinopathy
d) G6PD deficiency

Answer: Cold AIHA
Cold agglutinin hemolytic anemia:
Cold agglutinin disease is an autoimmune disease characterized by the presence of high concentrations of circulating antibodies, usually IgM, directed against red blood cells.
Clinical symptoms result from binding of IgM to red cells at sites such as exposed fingers, toes and ears where the temperature is below 30 degree C.

Q-7. 35 year old female with adnexal mass, CA-125 raised and CA 19-9 normal
Gross and HPE is given as below. What is the diagnosis?

a) Dysgerminoma
b) Papillary serous cystadenocarcinoma
c) Teratoma
d) Chorio-carcinoma

Answer: Dysgerminoma
Dysgerminoma may occur in childhood, but 75 % occur in second and third decades.
Most of these tumors have no endocrine function. A few produce elevated levels of chorionic gonadotropin and may have Syncytio-trophoblastic giant cells on histological examination.
Dysgerminoma (In above image) shows polyhedral tumor cells with round nuclei and adjacent inflammation.
Useful tumor markers for Dysgerminoma:
Inhibin A and B
Cancer antigen 125 (CA-125)

Q-8. In urine cytology of post renal transplant patient, marked structure is

a) Hyaline cast
b) Decoy cells
c) Charcot Leyden crystal
d) Tubular epithelial cells

Answer: Decoy cells
Human Polyoma virus causes renal dysfunction and graft loss as a result of tubulo-interstial nephritis in renal transplant recipients after reactivation of latent virus in renal epithelium.
The infected cells, characterized by large homogenous inclusions in the urinary sediments are termed Decoy cells.

Q-9. Patient presents with constipation, diarrhea and weight loss. It is due to
HPE is as follow

a) Entamoeba
b) Giardia
c) Whipple
d) H. pylori

Answer: Giardia
Giardia in stool smears:
Trophozoites are pear shaped and bi-nucleated.
Giardia in duodenal biopsy:
Teeming with sickle shaped trophozoites
As Giardia doesn’t actually invade mucosa, small intestine morphology may be virtually normal.

Q-10. A patient after trauma has respiratory discomfort. Ventilation tried but not helpful. HPE of lung shows

a) Air embolism
b) Fat embolism
c) Diffuse damage due to ventilation pressure
d) Diffuse alveolar hemoglobin with pulmonary edema

Answer: Fat embolism
Fat embolism:
Fat embolism syndrome is characterized by pulmonary insufficiency, neurological symptoms, anemia and thrombocytopenia.
Symptoms typically begin 1 to 3 days after injury with sudden onset of tachypnea, dyspnea and tachycardia.
A diffuse petechial rash in non-dependent areas (Related to rapid onset of thrombocytopenia) is useful in establishing diagnosis.

Frozen section of lung stained with oil red O showing multiple orange red fat globules of varying sizes in septal vasculature.

Q-11. A HIV patient presented with fever, neck rigidity and died in emergency department. After autopsy, gross with histopathological examination is gives as. It is due to

a) Echinococcus
b) Herpes infection
c) Toxoplasmosis
d) Cryptococcosis

Answer: Cryptococcosis
Major lesions caused by Cryptococcosis neoformans in central nervous system:
Involves meninges, cortical gray matter and basal nuclei
In immuno-suppressed patients, organisms may evoke virtually no inflammatory reaction, so gelatinous masses of fungi grow in meninges or expand the peri-vascular Virchow Robin Spaces within the grey matter, producing so called Soap bubble lesion.
In non-immuno-suppressed patients, the fungi induce a chronic granulomatous reaction composed of macrophages, lymphocytes and foreign body type cells.

Mucicarbine stain of Cryptococci (Sating red) in peri-vascular Virchow Robin Spaces of brain (Soap bubble lesion)