FMGE 2025 Practice Questions

Q: A chronic smoker who worked in a cement factory for the past 20 years developed mesothelioma. This association is most likely due to?

Asbestosis. ***Asbestosis*** - **Mesothelioma**, a malignant tumor of the pleura, is almost exclusively caused by occupational exposure to **asbestos fibers**. Cement factory work is a well-known source of this exposure. - The combination of smoking and asbestos exposure has a synergistic effect, massively increasing the risk for **bronchogenic carcinoma**, but asbestos alone is the primary risk factor for **mesothelioma**. *Bagassosis* - This is a type of **hypersensitivity pneumonitis** caused by inhaling dust from moldy **sugarcane** residue (bagasse). - It is an allergic inflammatory condition and is not associated with the development of **mesothelioma**. *Silicosis* - Caused by the inhalation of **silica dust**, common in mining and sandblasting, it classically affects the **upper lobes** of the lungs. - While it increases the risk for **tuberculosis** and lung cancer, it is not a recognized cause of **mesothelioma**. *Coal worker pneumoconiosis* - Also known as **"black lung disease"**, this condition is caused by the chronic inhalation of **coal dust**. - It is characterized by **coal macules** in the lungs and is not associated with an increased risk of **mesothelioma**.

Q: A 5-year-old child is brought to the outpatient department by his mother with irritability, poor school performance, and a history of recurrent ear infections. Otoscopic examination shows a dull, retracted tympanic membrane with fluid behind it. There is no blood clot present in the ear. What is the most likely diagnosis?

Otitis media with effusion. ***Otitis media with effusion***- This condition is characterized by the presence of **non-purulent fluid (effusion)** in the middle ear space without signs or symptoms of acute infection (such as fever or severe pain).- The otoscopic findings of a **dull, retracted tympanic membrane** with fluid behind it, coupled with symptoms suggesting chronic hearing loss (**poor school performance** and irritability), are classic for OME, or "**glue ear**." *Acute otitis media*- AOM is generally associated with the acute onset of **otalgia** (ear pain) and often fever, along with a key otoscopic finding of a **bulging**, erythematous, and immobile **tympanic membrane**.- The absence of acute inflammatory signs and the description of a retracted, rather than bulging, TM distinguishes this chronic finding from an acute infection. *Otitis externa*- This condition involves inflammation and infection of the **external auditory canal**; the middle ear and the fluid described are not typically affected.- Key clinical findings involve tenderness upon manipulation of the **tragus** or **pinna**, often with swelling and exudate limited to the ear canal. *Cholesteatoma*- Cholesteatoma is a destructive process involving a collection of **squamous epithelium** (a “pearly mass”) that usually causes **foul-smelling chronic otorrhea** due to bone erosion.- While chronic retraction of the TM can lead to its formation, the primary finding here is simply **effusion (fluid)**, not the characteristic highly destructive epidermal mass.

Q: A 20-year-old male was admitted with fever, headache and retro-orbital pain with rash. The tourniquet test is positive. What is the diagnosis?

Dengue hemorrhagic fever. ***Dengue hemorrhagic fever***- The combination of high fever, **headache**, **retro-orbital pain**, and rash is characteristic of classic Dengue fever (breakbone fever) [1].- A **positive tourniquet test** suggests increased capillary fragility, which, along with the other symptoms, strongly indicates progression toward **Dengue hemorrhagic fever (DHF)** [1].*Malaria*- Malaria is characterized by cyclical fever patterns (such as tertian or quartan), often associated with severe chills and sweats, which are not mentioned here.- It typically does not cause prominent retro-orbital pain or lead to a positive **tourniquet test** as a primary finding.*Measles*- Measles is typically preceded by a prodrome including cough, coryza, and conjunctivitis, followed by the appearance of **Koplik spots** (buccal lesions).- The rash starts on the face and spreads downwards, and while fever is present, the key combination of **retro-orbital pain** and a positive tourniquet test is not characteristic.*Japanese encephalitis*- This is primarily a **neuroinvasive disease** transmitted by Culex mosquitoes, leading to symptoms like altered mental status, seizures, and focal neurological deficits.- Simple fever, headache, and rash without significant encephalopathy make this diagnosis less likely, and it is not typically associated with the **tourniquet test**.

Q: Which organism is most commonly responsible for gas gangrene?

Clostridium perfringens. ***Clostridium perfringens*** - This **anaerobic, Gram-positive** rod is the most common cause of gas gangrene (or **myonecrosis**) due to its rapid production of potent toxins, especially $\alpha$-toxin (a **lecithinase**). - It is found ubiquitously in soil and the GI tract and typically infects deep penetrating wounds, leading to rapid tissue destruction and gas formation (crepitus). *Clostridium difficile* - This organism primarily causes **antibiotic-associated diarrhea** and **pseudomembranous colitis** due to the production of Toxin A (enterotoxin) and Toxin B (cytotoxin). - It is rarely involved in tissue infections or gas gangrene. *Clostridium tetani* - This bacterium is the causative agent of **tetanus**, a neurological disorder characterized by muscle spasms and locked jaw. - Tetanus symptoms are due to the production of the neurotoxin **tetanospasmin**, which blocks inhibitory neurotransmitters. *Clostridium botulinum* - This organism produces the potent **botulinum toxin**, which causes **flaccid paralysis** (botulism) by preventing the release of acetylcholine at the neuromuscular junction. - It is associated with food poisoning or infant botulism, not typically gas gangrene.

Q: A woman was bitten by a rabid dog. The dog developed symptoms and died within a week. What is the best method for post-mortem diagnosis of rabies in the dog?

DFAT. ***DFAT (Direct Fluorescent Antibody Test)*** - The **Direct Fluorescent Antibody Test (DFAT)** is the **gold standard** for post-mortem diagnosis of rabies in animals - It detects rabies viral antigen in **brain tissue** with high sensitivity and specificity - Provides **rapid results** (within hours) and is the WHO-recommended method for definitive diagnosis - Used worldwide as the standard confirmatory test for rabies in suspected animals *Detection of Negri bodies* - **Negri bodies** are pathognomonic eosinophilic cytoplasmic inclusions found in neurons (especially hippocampal pyramidal cells) - Detection has **low sensitivity** (only 50-80% of cases) and requires expert interpretation - While specific when present, their absence does not rule out rabies - Not reliable as the primary diagnostic method *Seller's staining* - **Seller's staining** is a classical histological technique specifically used to visualize Negri bodies - It is an **outdated method** with the same limitations as general Negri body detection - Has been largely replaced by more sensitive and specific methods like DFAT - Lower sensitivity compared to immunofluorescence techniques *Brain biopsy* - While brain tissue is the ideal specimen for rabies diagnosis, **brain biopsy** is not performed post-mortem - Post-mortem examination involves direct collection of brain tissue, not biopsy - For antemortem human diagnosis, less invasive methods (skin biopsy from nape of neck, corneal impressions) are preferred over brain biopsy

Q: A 3-month-old child was admitted with pneumonia. The microscopy shows the following image. Choose the correct organism.

Influenza. ***Influenza*** - The image displays a virus with two key surface glycoproteins: **Hemagglutinin (HA)** and **Neuraminidase (NA)**. These proteins are the defining structural features of the Influenza virus and are crucial for its entry into and exit from host cells. - Influenza virus is a well-known cause of respiratory illnesses, including severe **pneumonia**, particularly in high-risk groups such as infants, the elderly, and immunocompromised individuals. *Rotavirus* - Rotavirus is the leading cause of severe **gastroenteritis** (diarrhea and vomiting) in infants and young children; it is not a primary cause of pneumonia. - It is a **non-enveloped** virus with a distinct wheel-like appearance (hence the name "rota"), which is structurally different from the enveloped virus shown in the diagram. *Hepatitis virus* - Hepatitis viruses (A, B, C, etc.) are hepatotropic, meaning they primarily infect and cause inflammation of the **liver (hepatitis)**, and are not associated with respiratory infections like pneumonia. - Their viral structures and surface antigens are different; for example, Hepatitis B virus has **HBsAg** on its surface, not HA and NA. *Respiratory syncytial virus* - While RSV is a very common cause of **pneumonia** and **bronchiolitis** in infants, its viral structure differs from the one depicted. - RSV belongs to the *Paramyxoviridae* family and has **Fusion (F)** and **Attachment (G)** proteins on its surface, not Hemagglutinin and Neuraminidase.

Q: Identify the microorganism shown in the image.

Entamoeba histolytica. ***Entamoeba histolytica*** - The image displays the **trophozoite** stage, characterized by a single nucleus with a central, dot-like **karyosome**. - A key diagnostic feature seen here is the presence of ingested **red blood cells** within the cytoplasm, a phenomenon known as **erythrophagocytosis**, which indicates invasive disease. *Giardia lamblia* - *Giardia* trophozoites are pear-shaped and **binucleated**, often described as having a face-like appearance, which is distinct from the single nucleus seen in the image. - They are flagellated protozoa and do not phagocytose red blood cells. *Shigella dysenteriae* - *Shigella* is a **bacterium**, not a protozoan, and would appear as a small, rod-shaped organism under a microscope. - It lacks the complex eukaryotic structures, such as a distinct nucleus and cytoplasmic inclusions, that are visible in the provided image. *Campylobacter jejuni* - This is a **bacterium** known for its characteristic curved, S-shaped, or "gull-wing" morphology. - As a prokaryote, it is much smaller and structurally simpler than the large amoeboid parasite shown.

Q: A 25-year-old man presents with headaches, visual disturbances, and hypertension. MRI brain shows a cerebellar hemangioblastoma, and abdominal imaging reveals multiple cysts in the kidneys along with a solid renal mass suggestive of renal cell carcinoma. His father had similar findings and died from a brain tumor in his 40s. Which of the following chromosomal abnormalities is most likely associated with his condition?

Deletion on chromosome 3p. ***Deletion on chromosome 3p*** - This clinical presentation of **cerebellar hemangioblastoma**, **renal cell carcinoma (clear cell type)**, and multiple renal and pancreatic cysts in a familial context is highly characteristic of **Von Hippel-Lindau (VHL) disease**. [1] - VHL disease is caused by an inherited or sporadic inactivation (deletion or mutation) of the **VHL tumor suppressor gene** located on the short arm of chromosome 3 (**3p25.3**). [2] *Deletion on chromosome 13q* - Deletion of the **RB1 gene** on chromosome 13q is associated with **retinoblastoma** and an increased risk of **osteosarcoma**, not VHL disease. - The clinical picture of headaches, cerebellar mass, and renal cell carcinoma is distinct from the typical presentation of RB1-associated disorders. *Deletion on chromosome 17p* - Deletion or mutation of the **TP53 gene** on chromosome 17p is primarily associated with **Li-Fraumeni syndrome**, which increases the risk for a variety of cancers, including sarcomas, breast cancer, and adrenocortical carcinoma, but less commonly VHL-related tumors. - This deletion is not the genetic locus for the VHL tumor suppressor gene. *Trisomy of chromosome 12* - Trisomy 12 is a common chromosomal anomaly found in B-cell chronic lymphocytic leukemia (**CLL**) and some benign tumors like **uterine leiomyomas**. - It is an inappropriate anomaly for a familial syndrome presenting with hemangioblastoma and renal cell carcinoma. **References:** [1] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Manifestations Of Central And Peripheral Nervous System Disease, pp. 724-725. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Kidney, pp. 958-959.

Q: Mutation in which of the following genes is most commonly associated with medullary thyroid carcinoma?

RET. ***RET***- The **RET proto-oncogene** mutation is the defining genetic feature of medullary thyroid carcinoma (MTC), which arises from parafollicular C-cells. [1] - Germline mutations in **RET** are responsible for hereditary forms of MTC, including **Multiple Endocrine Neoplasia type 2 (MEN 2A and 2B)**, making it the most critical diagnostic marker. [1] *RAS* - Mutations in the **RAS family** of genes (NRAS, HRAS, KRAS) are highly prevalent in **follicular thyroid carcinoma (FTC)** and follicular variants of papillary thyroid carcinoma (PTC). - These mutations are typically associated with a less aggressive tumor phenotype compared to RET or BRAF alterations. *BRAF* - The **BRAF V600E mutation** is the most common genetic alteration found in **papillary thyroid carcinoma (PTC)**, specifically the classical and tall cell variants. - The presence of **BRAF V600E** often correlates with increased risk of aggressive features, such as lymph node metastasis and extrathyroidal extension in PTC. *TP53* - **TP53** is a tumor suppressor gene whose mutations are primarily seen in highly aggressive, **anaplastic (undifferentiated) thyroid carcinoma (ATC)**. - Mutations in **TP53** indicate a progression from well-differentiated tumors and are associated with a very poor prognosis. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Endocrine System, pp. 1139-1140.

Q: Hereditary non-polyposis colorectal cancer (HNPCC), also known as Lynch syndrome, is caused by mutations in which type of genes?

MMR. ***MMR*** - Hereditary non-polyposis colorectal cancer (**HNPCC**), also known as **Lynch syndrome**, is caused by germline mutations in **DNA Mismatch Repair (MMR)** genes [1]. - Defective MMR function, most commonly due to mutations in **MLH1**, **MSH2**, **MSH6**, or **PMS2**, leads to an accumulation of mutations throughout the genome, a state known as **microsatellite instability (MSI)**. *APC* - Mutations in the **APC** gene, a tumor suppressor, are the cause of **Familial Adenomatous Polyposis (FAP)**, a different hereditary colorectal cancer syndrome [1]. - FAP is characterized by the development of hundreds to thousands of colonic polyps, whereas HNPCC typically presents with fewer polyps that rapidly progress to carcinoma [1]. *MYC* - **MYC** is a **proto-oncogene** involved in cell cycle control and proliferation; its dysregulation contributes to the development of many cancers, but it is not the primary genetic cause of HNPCC. - It is not a DNA repair gene, but rather a transcription factor that, when overexpressed, promotes uncontrolled cell growth. *TERT1* - This likely refers to the **TERT** gene, which encodes **telomerase reverse transcriptase**, an enzyme essential for maintaining telomere length. - While reactivation of **telomerase** is a critical step for cellular immortalization in many cancers, inherited mutations in this gene are not the cause of Lynch syndrome. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Gastrointestinal Tract, pp. 817, 821-822.

Question 1

A chronic smoker who worked in a cement factory for the past 20 years developed mesothelioma. This association is most likely due to?

Accepted Answer

Asbestosis

Answer

Silicosis

Answer

Coal worker pneumoconiosis

Answer

Bagassosis

Question 2

A 5-year-old child is brought to the outpatient department by his mother with irritability, poor school performance, and a history of recurrent ear infections. Otoscopic examination shows a dull, retracted tympanic membrane with fluid behind it. There is no blood clot present in the ear. What is the most likely diagnosis?

Accepted Answer

Otitis media with effusion

Answer

Acute otitis media

Answer

Otitis externa

Answer

Cholesteatoma

Question 3

A 20-year-old male was admitted with fever, headache and retro-orbital pain with rash. The tourniquet test is positive. What is the diagnosis?

Accepted Answer

Dengue hemorrhagic fever

Answer

Malaria

Answer

Japanese encephalitis

Answer

Measles

Question 4

Which organism is most commonly responsible for gas gangrene?

Accepted Answer

Clostridium perfringens

Answer

Clostridium difficile

Answer

Clostridium tetani

Answer

Clostridium botulinum

Question 5

A woman was bitten by a rabid dog. The dog developed symptoms and died within a week. What is the best method for post-mortem diagnosis of rabies in the dog?

Accepted Answer

DFAT

Answer

Detection of Negri bodies

Answer

Brain biopsy

Answer

Seller’s staining

Question 6

A 3-month-old child was admitted with pneumonia. The microscopy shows the following image. Choose the correct organism.

Accepted Answer

Influenza

Answer

Rotavirus

Answer

Hepatitis virus

Answer

Respiratory syncytial virus

Question 7

Identify the microorganism shown in the image.

Accepted Answer

Entamoeba histolytica

Answer

Giardia lamblia

Answer

Campylobacter jejuni

Answer

Shigella dysenteriae

Question 8

A 25-year-old man presents with headaches, visual disturbances, and hypertension. MRI brain shows a cerebellar hemangioblastoma, and abdominal imaging reveals multiple cysts in the kidneys along with a solid renal mass suggestive of renal cell carcinoma. His father had similar findings and died from a brain tumor in his 40s. Which of the following chromosomal abnormalities is most likely associated with his condition?

Accepted Answer

Deletion on chromosome 3p

Answer

Trisomy of chromosome 12

Answer

Deletion on chromosome 17p

Answer

Deletion on chromosome 13q

Question 9

Mutation in which of the following genes is most commonly associated with medullary thyroid carcinoma?

Accepted Answer

RET

Answer

RAS

Answer

BRAF

Answer

TP53

Question 10

Hereditary non-polyposis colorectal cancer (HNPCC), also known as Lynch syndrome, is caused by mutations in which type of genes?

Accepted Answer

MMR

Answer

APC

Answer

TERT1

Answer

MYC

FMGE 2025

Community Medicine

ENT

Internal Medicine

Microbiology

Pathology