Anatomy
1 questionsA 45-year-old woman presented with tingling sensation of lateral 3 digits with loss of sensation of base of thumb on the dorsal aspect of the hand. Which is the nerve involved?
FMGE 2025 - Anatomy FMGE Practice Questions and MCQs
Question 1: A 45-year-old woman presented with tingling sensation of lateral 3 digits with loss of sensation of base of thumb on the dorsal aspect of the hand. Which is the nerve involved?
- A. Median nerve
- B. AIN
- C. Radial nerve (Correct Answer)
- D. Ulnar nerve
Explanation: ***Radial nerve*** - The **superficial branch of the radial nerve** provides sensory innervation to the dorsal aspect of the hand, including the dorsal surface of the thumb, index, middle, and the radial half of the ring finger up to the nail beds [1]. - The patient's symptoms of sensory loss at the **dorsal base of the thumb** (anatomical snuffbox) and tingling in the lateral digits are classic signs of superficial radial nerve involvement [1]. *Ulnar nerve* - The **ulnar nerve** provides sensation to the medial one and a half digits (the little finger and the medial half of the ring finger) on both the palmar and dorsal sides [1]. - Involvement of the ulnar nerve would not cause sensory changes in the lateral three digits or the thumb. *Median nerve* - The **median nerve** supplies sensation to the palmar aspect of the lateral three and a half digits and the nail beds on the dorsal side [1]. - It does not supply the dorsal aspect of the hand or the base of the thumb, which is a key localizing feature in this case. Common entrapment leads to **carpal tunnel syndrome** [2]. *AIN* - The **Anterior Interosseous Nerve (AIN)** is a purely **motor** branch of the median nerve [2]. - An injury to the AIN would result in motor weakness, specifically an inability to flex the thumb and index finger to make an 'OK' sign, but would not cause any sensory loss [2].
Microbiology
3 questionsPatient with HIV presenting with bouts of cough and fever. Which medium is appropriate for diagnosis?
A firefighter was admitted with fever, cough, culture shown in the image reveals gram-negative, oxidase-positive bacilli. Colonies transilluminating while passing under UV light. Choose the correct agent.
A firefighter with fever and cough has a culture showing gram-negative, oxidase-positive bacilli with fluorescent colonies under UV light. Which of the following organisms is most likely causing the infection?
FMGE 2025 - Microbiology FMGE Practice Questions and MCQs
Question 1: Patient with HIV presenting with bouts of cough and fever. Which medium is appropriate for diagnosis?
- A. MacConkey agar
- B. Loeffler serum slope (LSS)
- C. Tinsdale media
- D. Lowenstein-Jensen (LJ) medium (Correct Answer)
Explanation: ***Lowenstein-Jensen (LJ) medium*** - This egg-based culture medium is the standard solid medium used globally for the isolation of **Mycobacterium tuberculosis**. - Given the patient's history of **HIV** and symptoms of cough and fever, **Pulmonary Tuberculosis (TB)** is the differential diagnosis most likely requiring this specialized medium. *Tinsdale media* - Tinsdale medium is specifically used for the primary isolation and identification of **Corynebacterium diphtheriae**. - The characteristic presentation of **diphtheria** (pseudomembrane, severe pharyngitis) differs significantly from the suspected chronic respiratory symptoms of TB. *MacConkey agar* - This is a selective and differential medium designed to isolate and differentiate **Gram-negative enteric bacilli** (e.g., *E. coli*, *Salmonella*). - It is completely inadequate for the isolation of the slow-growing, **acid-fast bacilli** characteristic of mycobacteria. *Loeffler serum slope (LSS)* - Loeffler serum slope is an enrichment medium primarily used to promote the growth and demonstration of characteristic morphology in **Corynebacterium diphtheriae**. - While sometimes used for initial inoculum, it is not the definitive medium required for the isolation of **Mycobacterium tuberculosis** due to its composition and intended purpose.
Question 2: A firefighter was admitted with fever, cough, culture shown in the image reveals gram-negative, oxidase-positive bacilli. Colonies transilluminating while passing under UV light. Choose the correct agent.
- A. Staphylococcus aureus
- B. Pseudomonas aeruginosa (Correct Answer)
- C. Serratia
- D. Klebsiella
Explanation: ***Pseudomonas aeruginosa*** - This organism is a **gram-negative**, **oxidase-positive** bacillus, matching the description. The image shows growth with a characteristic green pigment (**pyocyanin** and **pyoverdin**). - The key identifier is the production of **pyoverdin**, a fluorescent siderophore, which causes the colonies to transilluminate under UV light. *Klebsiella* - *Klebsiella* is **oxidase-negative**, which rules it out based on the biochemical test results provided. - It typically produces large, **mucoid colonies** due to its prominent capsule and is a lactose fermenter, features not described here. *Staphylococcus aureus* - *Staphylococcus aureus* is a **gram-positive coccus**, not a gram-negative bacillus, making it incorrect based on the initial microscopy. - It is also **oxidase-negative** and characteristically forms opaque, often golden-yellow colonies, not greenish fluorescent ones. *Serratia* - *Serratia* is a gram-negative bacillus but is **oxidase-negative**, which is inconsistent with the findings. - Certain species like *Serratia marcescens* are known for producing a red pigment called **prodigiosin**, especially at room temperature, not a green fluorescent pigment.
Question 3: A firefighter with fever and cough has a culture showing gram-negative, oxidase-positive bacilli with fluorescent colonies under UV light. Which of the following organisms is most likely causing the infection?
- A. Staphylococcus aureus
- B. Pseudomonas aeruginosa (Correct Answer)
- C. Serratia
- D. Klebsiella
Explanation: ***Pseudomonas aeruginosa***- This organism is a non-lactose fermenting, **Gram-negative bacillus** that is definitively **oxidase-positive**.- It characteristically produces the siderophore **pyoverdine**, which is fluorescent under UV light, confirming the most likely etiology.*Klebsiella*- *Klebsiella* species are **oxidase-negative** (**distinguishing factor**) and typically highly encapsulated, often causing consolidation in pneumonia.- They are also strong **lactose fermenters** and do not produce fluorescent pigments.*Staphylococcus aureus*- *S. aureus* is a **Gram-positive coccus** (stains purple) arranged in clusters, not a Gram-negative bacillus (stains pink).- It is non-motile, shows no fluorescence, and is identified by being coagulase and catalase positive.*Serratia*- *Serratia marcescens* is generally **oxidase-negative** (unlike the clinical finding) and belongs to the Enterobacteriaceae family.- Under room temperature, *Serratia* often produces a characteristic **red pigment** (**prodigiosin**), not a fluorescent pigment.
Pediatrics
2 questionsA 9-month-old child was admitted to ICU with a history of recurrent sinusitis and otitis media by Staphylococcus aureus. Blood test shows decreased serum IgA, IgG, IgM, IgE, and plasma B cells. What is the diagnosis?
Chronic malnutrition is best measured by?
FMGE 2025 - Pediatrics FMGE Practice Questions and MCQs
Question 1: A 9-month-old child was admitted to ICU with a history of recurrent sinusitis and otitis media by Staphylococcus aureus. Blood test shows decreased serum IgA, IgG, IgM, IgE, and plasma B cells. What is the diagnosis?
- A. Chronic granulomatous disease
- B. Bruton syndrome (Correct Answer)
- C. DiGeorge syndrome
- D. Ataxia telangiectasia
Explanation: ***Bruton syndrome***- This diagnosis (X-linked agammaglobulinemia or XLA) is defined by the failure of **B cell maturation** due to a mutation in the **BTK gene**, leading to near-total absence of mature B cells and plasma cells.- The clinical presentation is recurrent infections, often *S. aureus* and encapsulated bacteria, correlated with the drastic reduction of all serum **immunoglobulin levels** (IgA, IgG, IgM, IgE).*Ataxia telangiectasia*- This is an **autosomal recessive** T-cell/B-cell defect associated with defects in **DNA repair** (ATM gene), causing progressive cerebellar ataxia and oculocutaneous telangiectasias.- While associated with immunodeficiency, it typically presents with low **IgA** and **IgE**, not the complete absence of plasma B cells seen here.*Chronic granulomatous disease*- This is a phagocytic disorder due to a defect in the **NADPH oxidase** complex, preventing neutrophils from generating a respiratory burst necessary to kill catalase-positive organisms (like *S. aureus*).- Although the child has *S. aureus* infection, **serum Ig and B cell levels** remain normal, which contradicts the profound pan-hypogammaglobulinemia seen in this scenario.*DiGeorge syndrome*- Caused by defective development of the 3rd and 4th pharyngeal pouches, resulting in **T-cell deficiency** (thymic hypoplasia), **hypocalcemia**, and cardiac defects.- The primary immunodeficiency affects T cells, leading to susceptibility to **viral and fungal infections**; B cell numbers are usually normal, even though antibody production might be secondarily impaired.
Question 2: Chronic malnutrition is best measured by?
- A. Weight for height
- B. Body mass index
- C. Height for age (Correct Answer)
- D. Weight for age
Explanation: ***Height for age*** - This index measures **stunting**, which is the definitive indicator of **chronic malnutrition** (long-term failure to achieve expected height). - A low height-for-age indicates that a child has suffered from sustained nutritional deficiencies or repeated infections over a prolonged period. *Weight for age* - This index measures **underweight**, reflecting a mixture of both **acute** and **chronic malnutrition**. - Since it is influenced by both weight loss (wasting) and long-term growth delay (stunting), it is less specific than H/A for solely quantifying chronicity. *Weight for height* - This index measures **wasting**, which is the indicator of **acute malnutrition** (recent, rapid weight loss). - It assesses current nutritional status and is essential for identifying conditions like severe acute malnutrition (SAM). *Body mass index* - BMI is a measure of generalized nutritional status, often used to define overweight or obesity in adults, but it is **not the primary index** for assessing stunting in children. - While correlated with weight-for-height, it does not specifically capture the historical growth failure characterized by low height-for-age.
Pharmacology
1 questionsWhich anti-epileptic drug is commonly associated with gum hypertrophy and dizziness as side effects?
FMGE 2025 - Pharmacology FMGE Practice Questions and MCQs
Question 1: Which anti-epileptic drug is commonly associated with gum hypertrophy and dizziness as side effects?
- A. Carbamazepine
- B. Topiramate
- C. Phenytoin (Correct Answer)
- D. Levetiracetam
Explanation: ***Phenytoin*** - It is classically associated with **gingival hyperplasia** (gum hypertrophy) due to increased stimulation of **fibroblast activity** and **collagen synthesis** in the gingiva, which is a major distinction from other AEDs. - Dose-dependent **dizziness** and **ataxia** are very common CNS side effects, reflecting its non-linear kinetics and narrow therapeutic index. *Carbamazepine* - Its most characteristic serious side effects include **aplastic anemia** and agranulocytosis, requiring baseline and periodic complete blood counts (CBCs). - It is a potent inducer of **CYP450 enzymes** and frequently causes **hyponatremia** (via Syndrome of Inappropriate Antidiuretic Hormone secretion, SIADH). *Levetiracetam* - This drug is generally well-tolerated but is notably associated with significant **behavioral side effects** such as irritability, aggression, and mood instability. - It does not cause **gum hypertrophy** or significant liver enzyme induction, unlike Phenytoin or Carbamazepine. *Topiramate* - Commonly causes side effects related to cognition, often called **"Dopamax"**, leading to cognitive slowing, difficulty concentrating, and language problems. - Other unique side effects include **weight loss** and the formation of **kidney stones** (nephrolithiasis) due to inhibition of carbonic anhydrase.
Physiology
3 questionsWhich segment of the nephron has the lowest osmolality under the influence of antidiuretic hormone (ADH)?
Which of the following is the afferent limb of the corneal reflex?
Which of the following changes occurs during muscle contraction while exercising, as shown in the image?
FMGE 2025 - Physiology FMGE Practice Questions and MCQs
Question 1: Which segment of the nephron has the lowest osmolality under the influence of antidiuretic hormone (ADH)?
- A. Descending limb of the loop of Henle
- B. Collecting duct
- C. Late distal tubule
- D. Early distal tubule (Correct Answer)
Explanation: ***Early distal tubule*** - This segment is known as the **cortical diluting segment** because it actively reabsorbs solutes (Na+ and Cl-) via the **Na+-Cl- cotransporter** while being impermeable to water. - This mandatory solute removal ensures the tubular fluid is maximally diluted (hypoosmolar, often around 100 mOsm/L), a process that is independent of **ADH** levels. *Descending limb of the loop of Henle* - This segment is highly permeable to **water** but largely impermeable to solutes, causing water to flow out into the surrounding hypertonic medulla. - Consequently, the osmolality of the tubular fluid **increases** significantly as it moves down toward the loop hairpin turn, making it highly concentrated, not dilute. *Collecting duct* - The influence of **ADH** is to insert **aquaporin 2** channels into the apical membrane, making this segment highly permeable to water. - This allows massive water reabsorption out of the tubule, concentrating the urine and leading to a **high osmolality** within the tubule lumen, especially near the end. *Late distal tubule* - While the fluid here is dilute, some water reabsorption is possible in the presence of **ADH** due to ADH-sensitive aquaporins, similar to the collecting duct. - This water movement slightly increases the osmolality compared to the maximally dilute fluid produced earlier in the **early distal tubule**.
Question 2: Which of the following is the afferent limb of the corneal reflex?
- A. Facial nerve
- B. Trigeminal nerve (Correct Answer)
- C. Trochlear nerve
- D. Optic nerve
Explanation: ***Trigeminal nerve***- The **Trigeminal nerve (CN V)**, specifically its **ophthalmic division (V1)**, detects the tactile sensation on the cornea, making it the sensory input (afferent limb) of the reflex arc.- Sensory impulses travel through the nasociliary nerve (a branch of V1) to the **principal sensory nucleus of CN V** in the pons.*Optic nerve*- The **Optic nerve (CN II)** is crucial for the sense of **vision** and serves as the afferent limb for the **pupillary light reflex**.- It transmits light stimuli, whereas the corneal reflex is triggered by **tactile stimuli** (touch or pain).*Facial nerve*- The **Facial nerve (CN VII)** serves as the **efferent (motor) limb** of the reflex, responsible for causing the blink via innervation of the **orbicularis oculi** muscle.- It carries the motor command *away* from the nucleus to the muscle, contrasting with the afferent nerve which carries sensation *to* the nucleus.*Trochlear nerve*- The **Trochlear nerve (CN IV)** is a motor nerve responsible for innervating the **superior oblique muscle**, which controls eye movement (depression and intorsion).- It has no role in the sensation of the cornea or the motor response (blinking) that characterizes the corneal reflex.
Question 3: Which of the following changes occurs during muscle contraction while exercising, as shown in the image?
- A. M length increase
- B. M length increase and I decrease
- C. A length decrease
- D. I length decrease (Correct Answer)
Explanation: ***I length decrease*** - The **I band** is the region of the sarcomere containing only **thin filaments (actin)**. During contraction, these thin filaments slide over the thick filaments, causing the I band to shorten. - The shortening of the I band, along with the H zone, results in the **Z lines** moving closer together, which constitutes the shortening of the entire **sarcomere**. *M length increase* - The **M line** is a protein structure in the center of the H zone that anchors the **thick filaments (myosin)**. It is a line, not a band, and its own length does not change. - The region surrounding the M line, the **H zone**, actually *decreases* in width during contraction, it does not increase. *A length decrease* - The **A band** represents the entire length of the **thick myosin filaments**. The length of these filaments does not change during the sliding filament process of muscle contraction. - Because the thick filaments do not shorten, the length of the **A band remains constant** during both muscle contraction and relaxation. *M length increase and I decrease* - This option is partially correct, as the **I band** does decrease in length during contraction. - However, it is incorrect because the **M line** does not increase in length; it remains constant. The overall statement is therefore false.