Biochemistry
3 questionsWhich of the following enzymes is dependent on Vitamin C for its activity?
Which of the following enzymes is typically elevated in prostate cancer?
Which deficiency is most likely in a patient with delayed wound healing and alopecia?
FMGE 2025 - Biochemistry FMGE Practice Questions and MCQs
Question 61: Which of the following enzymes is dependent on Vitamin C for its activity?
- A. Lysyl oxidase
- B. Prolyl hydroxylase (Correct Answer)
- C. Lysyl dehydrogenase
- D. Hydroxyprolyl kinase
Explanation: ***Prolyl hydroxylase***- **Prolyl hydroxylase** requires **Vitamin C** (ascorbic acid) to reduce the ferric iron (Fe3+) in its active site back to **ferrous iron (Fe2+),** thereby maintaining its catalytic function.- This enzyme hydroxylates **proline** residues, a critical post-translational modification necessary for the stabilization and proper triple-helical winding of **collagen**; deficiency results in **scurvy**. *Lysyl dehydrogenase*- This enzyme is involved in **lysine catabolism** via deamination and is generally not associated with the direct role of Vitamin C in collagen synthesis.- It is distinct from **lysyl hydroxylase**, which *is* a Vitamin C-dependent enzyme modifying lysine in collagen. *Lysyl oxidase*- **Lysyl oxidase** is responsible for forming covalent **cross-links** between collagen and elastin molecules, stabilizing the extracellular matrix structure.- This enzyme requires **copper** (Cu2+) as a cofactor for its activity and is not directly dependent on Vitamin C. *Hydroxyprolyl kinase*- This is not a standard physiological enzyme involved in the key metabolic pathways of **collagen synthesis** or degradation.- Kinase activity concerns **phosphorylation**, which is unrelated to the **hydroxylation** mechanism essential for Vitamin C dependence in connective tissue metabolism.
Question 62: Which of the following enzymes is typically elevated in prostate cancer?
- A. Alpha-fetoprotein
- B. Lactate dehydrogenase
- C. Alkaline phosphatase
- D. Acid phosphatase (Correct Answer)
Explanation: ***Acid phosphatase***- While largely replaced by **Prostate-Specific Antigen (PSA)** for screening, **Prostatic Acid Phosphatase (PAP)** remains a strong enzymatic marker for prostate cancer, particularly useful in monitoring metastatic disease.- Significant elevations are often indicative of **extra-capsular extension** or **bone metastases** in advanced disease.*Alkaline phosphatase*- While generalized **Alkaline phosphatase (ALP)** can be elevated in prostate cancer, this is primarily due to **osteoblastic bone metastases**, not the tumor cells directly.- ALP is a non-specific marker primarily associated with **liver** or **generalized bone disease**.*Lactate dehydrogenase*- **Lactate dehydrogenase (LDH)** is a non-specific indicator of generalized **tissue injury** or high **tumor burden** across various malignancies (e.g., lymphomas, melanoma, germ cell tumors).- Its elevation reflects high cellular turnover/necrosis but is not a primary diagnostic marker specific to prostate cancer.*Alpha-fetoprotein*- **Alpha-fetoprotein (AFP)** is a crucial tumor marker for **hepatocellular carcinoma (HCC)** and **nonseminomatous testicular germ cell tumors** (like yolk sac tumors).- It is not typically elevated in prostate cancer and should not be used in its diagnosis or monitoring.
Question 63: Which deficiency is most likely in a patient with delayed wound healing and alopecia?
- A. Calcium
- B. Zinc (Correct Answer)
- C. Copper
- D. Vitamin D
Explanation: ***Zinc*** - **Zinc** is vital for numerous enzymatic reactions involved in protein synthesis, immune function, and cell membrane stability, impairment of which severely delays **wound healing** and tissue repair. - **Alopecia** is a classic dermatologic finding in zinc deficiency, often accompanied by **acrodermatitis enteropathica** (perioral and acral cutaneous lesions). - The combination of delayed wound healing and alopecia is highly characteristic of zinc deficiency. *Copper* - Copper deficiency typically manifests with **microcytic anemia** (refractory to iron) and **neutropenia** due to its role in iron metabolism and hematopoiesis. - While severe copper deficiency can rarely cause hair abnormalities (often described as "kinky hair" or hypopigmentation), it does not characteristically cause the combination of delayed wound healing and alopecia. - Neurological manifestations (myelopathy, peripheral neuropathy) are more prominent in copper deficiency. *Calcium* - Calcium deficiency primarily affects **bone health** (osteoporosis, osteomalacia) and **neuromuscular function** (tetany, paresthesias, seizures). - It does not typically cause delayed wound healing or alopecia. *Vitamin D* - Vitamin D deficiency mainly causes **musculoskeletal problems** (rickets in children, osteomalacia in adults, bone pain, muscle weakness). - While it has roles in immune function, it is not classically associated with the specific combination of delayed wound healing and alopecia.
Dermatology
2 questionsAn elderly female undergoing chemotherapy for breast cancer is experiencing significant hair loss. What is the most likely cause of her condition?
A neonate presents with a growing skin lesion, as shown in the image provided. The mother reports that the lesion has been increasing in size daily. What is the appropriate management?
FMGE 2025 - Dermatology FMGE Practice Questions and MCQs
Question 61: An elderly female undergoing chemotherapy for breast cancer is experiencing significant hair loss. What is the most likely cause of her condition?
- A. Alopecia Areata
- B. Trichotillomania
- C. Anagen Effluvium (Correct Answer)
- D. Telogen Effluvium
Explanation: ***Anagen Effluvium***- This condition is the abrupt cessation of cell division in the rapidly proliferating hair matrix, directly caused by cytotoxic agents (chemotherapy) used to treat **breast cancer**.- It results in the hair shaft narrowing and fracturing, leading to massive, acute hair shedding (often non-scarring) that occurs within days to weeks of starting the **chemotherapy treatment**.*Telogen Effluvium*- This type of hair loss involves premature shifting of hairs from the growth (anagen) to the resting (telogen) phase due to a major stressor (e.g., severe illness, childbirth).- The shedding typically appears **2 to 4 months after** the initial precipitating event, which is too delayed for the immediate hair loss associated with most chemotherapy regimens.*Trichotillomania*- This is a psychological disorder characterized by recurrent, irresistible urges to **pull out one's hair**, leading to hair loss.- The resulting alopecia is typically patchy, irregular, and features hairs of different lengths due to continuous pulling, contrasting sharply with the diffuse loss from chemotherapy.*Alopecia Areata*- This is an **autoimmune** disorder where T-lymphocytes attack the anagen hair follicles, resulting in distinct, usually circular or oval, non-scarring patches of hair loss.- It classically presents with "exclamation mark" hairs (hairs that are narrower near the scalp) and is not directly induced by cytotoxic chemotherapy.
Question 62: A neonate presents with a growing skin lesion, as shown in the image provided. The mother reports that the lesion has been increasing in size daily. What is the appropriate management?
- A. Observation (Correct Answer)
- B. Immediate Biopsy due to Malignancy Risk
- C. Cryotherapy
- D. Excision and Laser Therapy
Explanation: ***Observation*** - The image displays a classic **infantile hemangioma** (strawberry nevus), a benign vascular tumor that typically appears shortly after birth. These lesions characteristically undergo a rapid proliferation phase in the first few months, followed by spontaneous involution over several years. - For uncomplicated hemangiomas that do not obstruct vital functions (like vision or breathing), ulcerate, or cause significant disfigurement, **observation** is the standard management, as most resolve on their own. *Excision and Laser Therapy* - Surgical excision or laser therapy are typically reserved for complicated hemangiomas, such as those that are ulcerated, bleeding, or causing functional impairment. - These invasive procedures carry risks of scarring and are generally avoided for simple lesions that are expected to regress spontaneously. *Immediate Biopsy due to Malignancy Risk* - The clinical presentation is highly characteristic of a benign **infantile hemangioma**, making the risk of malignancy extremely low and a biopsy unnecessary in most cases. - A biopsy is only considered if the lesion has atypical features or if the diagnosis is uncertain, to rule out rare malignant vascular tumors. *Cryotherapy* - Cryotherapy is not a standard treatment for infantile hemangiomas as it may not penetrate deep enough to be effective and carries a high risk of causing scarring, hypopigmentation, and pain. - This modality is more appropriate for smaller, more superficial lesions like warts or actinic keratoses, not for vascular tumors.
Internal Medicine
1 questionsA TB patient with HIV begins ART and experiences deterioration in health after 2 months. What is the likely cause?
FMGE 2025 - Internal Medicine FMGE Practice Questions and MCQs
Question 61: A TB patient with HIV begins ART and experiences deterioration in health after 2 months. What is the likely cause?
- A. Development of drug resistance to ART
- B. Development of drug resistance to TB drugs
- C. Immunological changes in the body (Correct Answer)
- D. Drug-drug interactions between TB and ART medications
Explanation: ***Immunological changes in the body*** - The patient's deterioration 2 months after initiating ART is highly suggestive of **Immune Reconstitution Inflammatory Syndrome (IRIS)** [1]. - IRIS occurs when the partially restored immune system mounts an intense, often paradoxical, inflammatory response against high existing **Mycobacterium tuberculosis** antigen loads [1]. *Development of drug resistance to TB drugs* - If resistance developed, the patient would typically fail to improve or experience gradual worsening, consistent with inadequate **TB coverage**, not an acute, paradoxical inflammatory reaction. - Worsening due to drug resistance is usually not temporally linked to the start of ART and would require specific **drug sensitivity testing (DST)** for confirmation [1]. *Drug-drug interactions between TB and ART medications* - Significant drug-drug interactions (e.g., between **rifampicin** and certain ART drugs) typically lead to systemic toxicity or subtherapeutic drug levels, manifesting as virologic failure or liver injury, not acute inflammatory worsening of the underlying TB. - Interactions lead to either rapid ART failure or toxicity, but not the specific clinical picture of **paradoxical TB-IRIS** where infectious signs temporarily worsen. *Development of drug resistance to ART* - Resistance to ART typically manifests as a failure of the **HIV viral load** to decrease or subsequent increase, leading to chronic progression of AIDS, not acute deterioration via inflammation of latent or subclinical TB [1]. - Developing drug resistance often requires prolonged exposure to a suboptimal regimen and usually takes longer than 2 months to cause significant clinical decline via **virologic failure**.
Pharmacology
3 questionsA patient with penicillin allergy presents with fever, burning micturition, and hearing problems accompanied by dizziness. Which drug is the most appropriate for the management?
A 35-year-old male experiences headache, nausea, and shortness of breath while trekking. The physician prescribes a drug to alleviate his symptoms. The drug administered primarily acts on which part of the nephron?
Which of the following drug dosages is incorrect for the treatment of leprosy in adults?
FMGE 2025 - Pharmacology FMGE Practice Questions and MCQs
Question 61: A patient with penicillin allergy presents with fever, burning micturition, and hearing problems accompanied by dizziness. Which drug is the most appropriate for the management?
- A. Ciprofloxacin (Correct Answer)
- B. Ampicillin-Clavulanic acid
- C. Amikacin
- D. Azithromycin
Explanation: ***Ciprofloxacin***- Ciprofloxacin is a **fluoroquinolone** that provides excellent coverage against common **uropathogens** (like *E. coli*) and is the preferred choice for managing complicated UTIs in patients with a **penicillin allergy**.- It is the most appropriate choice because, unlike aminoglycosides, it does not carry a high risk of **ototoxicity** or **vestibulotoxicity**, which is crucial as the patient already presents with hearing problems and dizziness.*Azithromycin*- Azithromycin is a **macrolide** that is generally not the first-line empirical antibiotic for typical urinary tract infections (UTIs) due to higher resistance rates among common uropathogens.- While safe in penicillin allergy, its primary spectrum targets atypical pathogens, making it less suitable than Ciprofloxacin for suspected UTIs complicated by fever.*Amikacin*- Amikacin is an **aminoglycoside** known to cause significant **ototoxicity** (leading to hearing loss) and **vestibulotoxicity** (causing dizziness and imbalance).- Given the patient already presents with hearing problems and dizziness, administering Amikacin is **absolutely contraindicated** as it would severely worsen these existing neurotoxic symptoms.*Ampicillin-Clavulanic acid*- This combination includes **Ampicillin**, which belongs to the **penicillin** class of antibiotics.- It is strictly contraindicated because the patient has a confirmed history of **penicillin allergy**, risking a potentially severe, life-threatening hypersensitivity reaction.
Question 62: A 35-year-old male experiences headache, nausea, and shortness of breath while trekking. The physician prescribes a drug to alleviate his symptoms. The drug administered primarily acts on which part of the nephron?
- A. Loop of Henle
- B. Collecting duct (CD)
- C. Proximal convoluted tubule (PCT) (Correct Answer)
- D. Distal convoluted tubule (DCT)
Explanation: ***Proximal convoluted tubule (PCT)***- The clinical presentation (headache, nausea, shortness of breath while trekking) is consistent with **Acute Mountain Sickness (AMS)**, which is typically prevented or treated with **Acetazolamide**.- **Acetazolamide** is a **carbonic anhydrase inhibitor** that acts primarily in the PCT, reducing bicarbonate reabsorption and inducing metabolic acidosis, which stimulates ventilation to counteract altitude-induced respiratory alkalosis.*Loop of Henle*- This segment is the primary site for **Loop Diuretics** (e.g., **Furosemide**), which inhibit the **Na+-K+-2Cl- cotransporter** in the thick ascending limb.- Loop diuretics promote powerful diuresis but are not the standard pharmacological choice for treating or preventing the symptoms of AMS.*Distal convoluted tubule (DCT)*- The DCT is the target site for **Thiazide Diuretics** (e.g., **Hydrochlorothiazide**), which block the **Na+-Cl- cotransporter**.- Thiazides primarily manage hypertension and edema and lack the necessary mechanism (carbonic anhydrase inhibition) to directly increase ventilation required for AMS treatment.*Collecting duct (CD)*- The collecting duct is where **Potassium-sparing diuretics** and **Aldosterone antagonists** (e.g., **Spironolactone**) exert their effects by controlling final sodium and potassium balance.- While these drugs can influence fluid balance, their primary actions are far removed from the need to induce metabolic acidosis to stimulate central respiratory drives in high-altitude illness.
Question 63: Which of the following drug dosages is incorrect for the treatment of leprosy in adults?
- A. Clofazimine 50 mg
- B. Dapsone 100 mg
- C. Rifampicin 450 mg (Correct Answer)
- D. Clofazimine 300 mg
Explanation: ***Rifampicin 450 mg*** - The standard dose of Rifampicin for leprosy treatment in adults is **600 mg once monthly** (supervised dose) as per WHO MDT regimen - 450 mg is an incorrect dosage and not part of the recommended treatment protocol - This makes it the correct answer to this negation question *Clofazimine 50 mg* - This is the correct **daily self-administered dose** of Clofazimine in Multibacillary (MB) leprosy - Used as part of the WHO MDT-MB regimen *Dapsone 100 mg* - This is the correct **daily dose** of Dapsone for both Paucibacillary (PB) and Multibacillary (MB) leprosy - Standard component of WHO MDT regimen *Clofazimine 300 mg* - This is the correct **monthly supervised dose** of Clofazimine in Multibacillary (MB) leprosy - Given once a month under supervision as part of WHO MDT-MB regimen
Radiology
1 questionsA patient presents with a history of dysphagia, which is more pronounced for liquids than solids. Which radiological sign is most likely to be seen?
FMGE 2025 - Radiology FMGE Practice Questions and MCQs
Question 61: A patient presents with a history of dysphagia, which is more pronounced for liquids than solids. Which radiological sign is most likely to be seen?
- A. Rat-tail sign (Correct Answer)
- B. Corkscrew esophagus
- C. Apple-core lesion
- D. Filling defect
Explanation: ***Rat-tail sign*** - Dysphagia that is more pronounced for liquids (**paradoxical dysphagia**) than solids is the hallmark symptom of **Achalasia**, a primary esophageal motility disorder. - The **rat-tail sign** (or **bird-beak sign**) seen on **barium swallow** is due to the non-relaxed, smoothly tapered distal esophagus resulting from **Lower Esophageal Sphincter (LES) failure** to relax. *Filling defect* - This is a general radiological term indicating any mass lesion protruding into the esophageal lumen, such as a **polyp**, **foreign body**, or a large tumor mass. - It is not specific to motility disorders like Achalasia, which cause smooth, concentric narrowing rather than a discrete filling absence. *Corkscrew esophagus* - This classic radiographic finding is characteristic of **Diffuse Esophageal Spasm (DES)**, where uncoordinated and severe contractions occur intermittently throughout the esophagus. - DES typically causes intermittent dysphagia and significant non-cardiac **chest pain**, and the dysphagia pattern is usually not strictly *liquids more than solids*. *Apple-core lesion* - The **apple-core lesion** (or **napkin-ring sign**) is the classical appearance of an infiltrative, malignant stricture, most commonly seen in cases of advanced **esophageal carcinoma**. - Malignant strictures cause progressive dysphagia, typically starting with difficulty swallowing **solids before liquids**, which contradicts the patient’s presentation.