Anatomy
3 questionsA renal biopsy image is shown. Identify the cells marked in the histological section.
Identify the lymphatic structure from the histology section given below?
Which of the following images displays the characteristic histology of the Thymus?
FMGE 2025 - Anatomy FMGE Practice Questions and MCQs
Question 41: A renal biopsy image is shown. Identify the cells marked in the histological section.
- A. Podocytes
- B. Lacis cells (Correct Answer)
- C. Juxtaglomerular (JG) cells
- D. Macula densa
Explanation: ***Lacis cells*** - The highlighted cells are **extraglomerular mesangial cells**, also known as Lacis cells, located in the triangular space between the afferent arteriole, efferent arteriole, and macula densa at the vascular pole of the glomerulus. - They are part of the **juxtaglomerular apparatus (JGA)** and are thought to play a role in transmitting signals from the macula densa to the juxtaglomerular cells, contributing to **tubuloglomerular feedback**. *Macula densa* - These are specialized, densely packed epithelial cells in the wall of the **distal convoluted tubule** where it contacts the glomerulus. The highlighted cells are situated outside of any tubule. - Macula densa cells function as **chemoreceptors** that monitor the **sodium chloride** concentration in the tubular fluid, regulating renin release and glomerular filtration rate. *Juxtaglomerular (JG) cells* - These are modified smooth muscle cells located primarily in the wall of the **afferent arteriole**. The cells in the image are not within an arteriolar wall. - JG cells synthesize, store, and secrete **renin**, and they function as **mechanoreceptors** by sensing changes in blood pressure within the afferent arteriole. *Podocytes* - These are specialized cells located **inside Bowman's capsule**, wrapping around the glomerular capillaries. The highlighted cells are distinctly **extraglomerular** (outside the glomerulus). - Podocytes form **filtration slits** with their interdigitating foot processes (**pedicels**), which are a critical component of the glomerular filtration barrier.
Question 42: Identify the lymphatic structure from the histology section given below?
- A. Spleen
- B. Lymph node
- C. Tonsil
- D. Thymus (Correct Answer)
Explanation: ***Thymus*** - The histology shows lymphoid tissue organized into **lobules** separated by connective tissue septa, with each lobule having a darkly stained outer **cortex** and a paler inner **medulla**. - The medulla contains **Hassall's corpuscles**, which are pathognomonic for the thymus, and the cortex lacks the germinal centers found in other lymphoid organs. *Tonsil* - Tonsils are characterized by an overlying **stratified squamous epithelium** that invaginates to form deep **tonsillar crypts**, neither of which is present in this image. - They contain numerous lymphoid follicles with prominent germinal centers but lack the distinct lobulated cortico-medullary architecture of the thymus. *Lymph node* - A lymph node has a distinct architecture with a **subcapsular sinus**, a cortex with B-cell follicles, a paracortex, and a medulla with medullary cords and sinuses, which is structurally different from the image provided. - The lobulated pattern with clear cortico-medullary differentiation within each lobule is a key feature of the thymus, not a lymph node. *Spleen* - The spleen's parenchyma is divided into **red pulp** (containing sinusoids) and **white pulp** (lymphoid tissue), an organization not seen in this section. - Splenic white pulp is characterized by a **central arteriole** surrounded by a **periarteriolar lymphoid sheath (PALS)**, a feature absent in the image.
Question 43: Which of the following images displays the characteristic histology of the Thymus?
- A. Image of Spleen
- B. Image of Thymus (Correct Answer)
- C. Image of Lymph node
- D. Image of Tonsil
Explanation: ***Image of Thymus*** - The image correctly illustrates the key histological features of the thymus, including the division of thymic lobules into a dark outer **cortex** and a lighter inner **medulla**. - A pathognomonic feature shown is the presence of **Hassall's (thymic) corpuscles**, which are whorls of epithelial reticular cells found exclusively in the thymic medulla. *Image of Tonsil* - Tonsillar histology is characterized by deep invaginations called **tonsillar crypts** and numerous **lymphoid follicles** with prominent germinal centers, neither of which are depicted in the image. - Tonsils are covered by **stratified squamous epithelium** (in palatine and lingual tonsils) or pseudostratified columnar epithelium (in pharyngeal tonsils), a feature not seen in the thymus. *Image of Lymph node* - A lymph node has a distinct architecture with a **cortex** containing **lymphoid follicles**, a **paracortex**, and a **medulla** with medullary cords and sinuses, which is structurally different from the image provided. - Lymph nodes are surrounded by a capsule with afferent lymphatic vessels and a **subcapsular sinus**, features that are absent in the thymus. *Image of Spleen* - Splenic histology is organized into **red pulp** and **white pulp**. The white pulp consists of **lymphoid follicles** and **periarteriolar lymphoid sheaths (PALS)** surrounding a central arteriole, which is not shown. - The red pulp, which makes up the majority of the spleen, contains **splenic sinusoids** and the **cords of Billroth**, structures for filtering blood that are absent in the thymus.
Dermatology
1 questionsA person with the H/o long-term sexual relationship presented with painful ulcers on his genitals with tender lymphadenopathy. What is the diagnosis?
FMGE 2025 - Dermatology FMGE Practice Questions and MCQs
Question 41: A person with the H/o long-term sexual relationship presented with painful ulcers on his genitals with tender lymphadenopathy. What is the diagnosis?
- A. LGV
- B. Chlamydia
- C. Gonorrhoea
- D. Chancroid (Correct Answer)
Explanation: ***Chancroid*** - Caused by the bacterium **_Haemophilus ducreyi_**, it classically presents with one or more deep, painful genital ulcers that have ragged, undermined borders and a purulent base. - It is characteristically associated with tender, suppurative inguinal lymphadenopathy, often unilateral, which is consistent with the patient's presentation. *Gonorrhoea* - Caused by **_Neisseria gonorrhoeae_**, it typically presents as **purulent urethritis** or cervicitis with discharge and dysuria. - While it can cause systemic infection, painful genital ulcers are not a characteristic feature of a primary gonococcal infection. *Chlamydia* - Caused by **_Chlamydia trachomatis_** (serovars D-K), it is a leading cause of nongonococcal urethritis and is frequently asymptomatic, especially in women. - This infection does not typically cause painful genital ulcers; its presentation is more commonly urethritis, cervicitis, or pelvic inflammatory disease. *LGV* - Lymphogranuloma venereum (LGV) is caused by invasive serovars (L1, L2, L3) of **_Chlamydia trachomatis_**. - It typically begins with a small, transient, **painless** papule or ulcer, followed by the development of painful inguinal lymphadenopathy (buboes), which differentiates it from the painful ulcers of chancroid.
Internal Medicine
1 questionsA young female has episodes of binge eating followed by self-induced vomiting. Which of the following acid- base disturbance is she likely to have?
FMGE 2025 - Internal Medicine FMGE Practice Questions and MCQs
Question 41: A young female has episodes of binge eating followed by self-induced vomiting. Which of the following acid- base disturbance is she likely to have?
- A. Respiratory acidosis
- B. Metabolic acidosis
- C. Respiratory alkalosis
- D. Metabolic alkalosis (Correct Answer)
Explanation: ***Metabolic alkalosis***- Self-induced vomiting results in the significant loss of **gastric hydrochloric acid (HCl)**, leading to a net gain of bicarbonate (HCO3-) in the blood, causing metabolic alkalosis [1, 2].- This condition is often exacerbated by **volume depletion** (due to fluid loss), leading to a state known as "**contraction alkalosis**," where the kidneys attempt to conserve volume even at the expense of excreting bicarbonate [1].*Respiratory acidosis*- This condition is characterized by **hypoventilation** leading to the retention of **carbon dioxide (CO2)** and an increase in carbonic acid, lowering the pH [2].- It is typically seen in conditions compromising respiratory drive or function, such as COPD exacerbations, narcotic overdose, or severe pneumonia.*Respiratory alkalosis*- This disturbance is caused by **hyperventilation**, which results in excessive loss of **carbon dioxide (CO2)**, leading to low PCO2 and elevated pH [3].- While anxiety may be a component of eating disorders, the primary physiologic effect of vomiting is related to acid loss, not sustained hyperventilation causing respiratory alkalosis.*Metabolic acidosis*- This is caused by either the **addition of fixed acids** (e.g., lactic acidosis, diabetic ketoacidosis) or the **loss of bicarbonate** (e.g., severe diarrhea or renal tubular dysfunction) [2].- Vomiting directly causes loss of acid, which is the opposite mechanism needed to induce metabolic acidosis [2].
Microbiology
2 questionsA patient’s laboratory results were positive for malarial antigen, and the Widal test findings were as follows: O ag >1:300, H ag >1:20, A >1:20, B >1:20. What is the most likely diagnosis?
A patient's sample is positive for infectious Hepatitis B. Choose the correct serological marker combination for this condition.
FMGE 2025 - Microbiology FMGE Practice Questions and MCQs
Question 41: A patient’s laboratory results were positive for malarial antigen, and the Widal test findings were as follows: O ag >1:300, H ag >1:20, A >1:20, B >1:20. What is the most likely diagnosis?
- A. Past infection
- B. Patient has taken TAB vaccine
- C. Recent infection by Salmonella spp (Correct Answer)
- D. Convalescence
Explanation: ***Recent infection by Salmonella spp*** - The **O antigen** titer (1:300) is significantly elevated (the diagnostic threshold is generally $\geq$1:160 or $\geq$1:320), strongly indicating a **recent or active infection** with *Salmonella typhi* (enteric fever). - The 'O' antigen is related to the **somatic LPS** and represents the IgM response, which is prominent during the acute phase of the infection. *Patient has taken TAB vaccine* - The **TAB vaccine** (Typhoid-Paratyphoid A and B) primarily generates high titers of **H (flagellar) antigen**, while the O antigen titer remains minimally elevated or low. - This patient exhibits a very high **O antigen** titer and low H antigen titer (1:20), ruling out recent vaccination as the sole cause of the serological picture. *Past infection* - **Past infection** is typically characterized by high and persistent **H (flagellar) antigen** titers, as the H antibody (IgG) persists longer than the O antibody (IgM). - The low H titer (1:20) and high O titer (1:300) suggest an **acute infection** rather than a remote or past infection. *Reconvalescence* - The **convalescent phase** (recovery) is marked by a decline in the acute-phase O antibody titers and sometimes a rise or persistence of H antibody titers. - The observed high O titer indicates an **ongoing acute process**, which is inconsistent with the late stage of recovery or reconvalescence.
Question 42: A patient's sample is positive for infectious Hepatitis B. Choose the correct serological marker combination for this condition.
- A. HBcAg
- B. HBeAg
- C. HBs + Anti Hbe
- D. HBsAg + HBeAg (Correct Answer)
Explanation: ***Correct: HBsAg + HBeAg*** - **HBsAg (Hepatitis B surface antigen)** indicates active HBV infection (acute or chronic) - **HBeAg (Hepatitis B e antigen)** indicates active viral replication and **high infectivity** - This combination is the hallmark of **infectious/highly contagious Hepatitis B** with active virus replication - High viral load (HBV DNA levels typically >10^5 copies/mL) *Incorrect: HBcAg* - Core antigen is **not detectable in serum** - only detectable in liver tissue - Anti-HBc antibodies are detected in serum, not HBcAg itself *Incorrect: HBeAg alone* - While HBeAg indicates infectivity, **HBsAg must be present** for active infection - HBeAg without HBsAg context is incomplete for diagnosis *Incorrect: HBsAg + Anti-HBe* - This pattern indicates **low replicative phase** (inactive carrier or chronic infection with seroconversion) - Anti-HBe suggests decreased viral replication and **lower infectivity** - This is the opposite of "infectious" Hepatitis B
Pediatrics
2 questionsA child with fused carpal bones comes to your clinic. What is the gene associated with Hand-Foot-Genital Syndrome?
A 4-year-old child with mid-arm circumference of 105mm, upon providing therapeutic food, eagerly completed all of it. This patient is considered under?
FMGE 2025 - Pediatrics FMGE Practice Questions and MCQs
Question 41: A child with fused carpal bones comes to your clinic. What is the gene associated with Hand-Foot-Genital Syndrome?
- A. BCL6
- B. HOXA13 (Correct Answer)
- C. FGFR
- D. COL11
Explanation: ***HOXA13 (Correct Answer)*** - Mutations in the **HOXA13** gene, a member of the HOX family of transcription factors, are responsible for **Hand-Foot-Genital Syndrome (HFGS)** - HFGS is an autosomal dominant disorder characterized by skeletal defects, including **fused carpal and tarsal bones** (as presented in this case), short digits, and genitourinary anomalies - The carpal fusion is a classic diagnostic feature of HOXA13 mutations *Incorrect: BCL6* - **BCL6** (B-cell lymphoma 6) is a transcriptional repressor primarily known for its role in regulating B-cell maturation and germinal center formation - Mutations or translocations involving BCL6 are implicated in **diffuse large B-cell lymphoma** and follicular lymphoma, not congenital skeletal abnormalities *Incorrect: FGFR* - **FGFR** (Fibroblast Growth Factor Receptor) genes are associated with skeletal dysplasias involving abnormal endochondral ossification - Mutations in FGFR genes cause conditions like **Achondroplasia** (FGFR3) or **craniosynostoses** (FGFR2), rather than the specific carpal-tarsal fusion pattern seen in HOXA13 defects *Incorrect: COL11* - **COL11A1** and **COL11A2** genes encode collagen type XI and are associated with **Stickler syndrome** and various collagenopathies - These conditions affect connective tissue broadly, causing features like myopia, hearing loss, and joint hypermobility, rather than the isolated carpal fusions characteristic of Hand-Foot-Genital Syndrome
Question 42: A 4-year-old child with mid-arm circumference of 105mm, upon providing therapeutic food, eagerly completed all of it. This patient is considered under?
- A. Uncomplicated SAM (Correct Answer)
- B. Complicated SAM
- C. Acute malnutrition
- D. Normal nutrition
Explanation: ***Uncomplicated SAM*** - A Mid-Arm Circumference (**MUAC**) of 105mm in a child aged 6–59 months meets the criterion for defining **Severe Acute Malnutrition (SAM)** (MUAC < 115mm). - The eager consumption of therapeutic food implies a **good appetite** (passing the appetite test), which classifies the case as *uncomplicated*, enabling **outpatient treatment** with Ready-to-Use Therapeutic Food (RUTF). - This is the **most specific and accurate classification** for management purposes. *Complicated SAM* - This classification is reserved for children with SAM who fail the **appetite test**, have **bilateral pitting edema**, or present with medical danger signs (e.g., lethargy, severe vomiting, hypothermia, hypoglycemia). - Children with complicated SAM require immediate **inpatient care** for specialized treatment and stabilization. - Since this child has a **good appetite** and no complications mentioned, this classification is incorrect. *Acute malnutrition* - While technically SAM is a form of acute malnutrition, this term is **too broad and non-specific** for clinical management. - Acute malnutrition encompasses both Severe Acute Malnutrition (**SAM**) and Moderate Acute Malnutrition (MAM). - The question requires the **most specific classification** to guide appropriate treatment (RUTF for uncomplicated SAM vs. supplementary foods for MAM vs. inpatient care for complicated SAM). - This is therefore **not the best answer** despite being partially correct. *Normal nutrition* - A MUAC of 105mm is significantly below the threshold for **normal nutritional status** (typically MUAC > 125mm or > 135mm, depending on classification system). - Normal nutritional status would not necessitate the provision of specialized therapeutic food. - This option is clearly incorrect.
Physiology
1 questionsDehydration is more severe in infants compared to adults. What is the PRIMARY reason for this increased susceptibility?
FMGE 2025 - Physiology FMGE Practice Questions and MCQs
Question 41: Dehydration is more severe in infants compared to adults. What is the PRIMARY reason for this increased susceptibility?
- A. Total body water in infants is more than in adults (Correct Answer)
- B. Intracellular fluid (ICF) is more than extracellular fluid (ECF)
- C. Extracellular fluid (ECF) is more than intracellular fluid (ICF)
- D. Extracellular fluid equals intracellular fluid
Explanation: ***Total body water in infants is more than in adults*** - Newborn infants have a significantly higher percentage of **Total Body Water (TBW)**, approximately **75-80%** of their body weight, compared to adults (~60%). - This large volume of water, combined with their greater **surface area-to-volume ratio** and higher **metabolic rate**, necessitates rapid fluid turnover, dramatically increasing their risk of severe dehydration. - This is the **primary physiological reason** why infants are more vulnerable to dehydration compared to adults. *Intracellular fluid (ICF) is more than extracellular fluid (ECF)* - This fluid distribution pattern is characteristic of **adults and older children**, not infants. - In young infants, the **ECF** compartment is actually greater than or nearly equal to the **ICF** compartment. - This represents the adult fluid distribution pattern, not the infant pattern. *Extracellular fluid (ECF) is more than intracellular fluid (ICF)* - While this statement is **anatomically true** for newborns (who have a disproportionately large ECF volume), it does not explain the **primary mechanism** of increased dehydration risk. - The ECF:ICF ratio changes with age, but the overall higher **total body water percentage** is the fundamental reason for severe dehydration susceptibility. - This is a characteristic of infant fluid distribution but not the main answer to why dehydration is more severe. *Extracellular fluid equals intracellular fluid* - In normal physiological states, the volume of the **ECF** compartment rarely equals the volume of the **ICF** compartment at any age. - In infants, ECF typically exceeds ICF; in adults, ICF exceeds ECF. - This statement is not accurate for either infants or adults.