Biochemistry
1 questionsWhich of the following interfere with iron absorption?
FMGE 2019 - Biochemistry FMGE Practice Questions and MCQs
Question 181: Which of the following interfere with iron absorption?
- A. Myoglobin
- B. Vitamin C
- C. Phytates (Correct Answer)
- D. Oxalate
Explanation: ***Phytates*** - **Phytates** (phytic acid), found in plant-based foods like whole grains, legumes, nuts, and seeds, are **potent inhibitors of non-heme iron absorption**. - They **chelate non-heme iron** and form insoluble complexes in the gastrointestinal tract, making it unavailable for absorption. - Phytates are considered **the most significant dietary inhibitor** of iron absorption among the options listed. *Myoglobin* - **Myoglobin is a heme-containing protein** found in muscle tissue and serves as an excellent dietary source of readily absorbable **heme iron**. - It does **not interfere** with iron absorption; instead, it provides bioavailable heme iron. *Vitamin C* - **Vitamin C** (ascorbic acid) significantly **enhances the absorption of non-heme iron** by reducing ferric iron (Fe³⁺) to ferrous iron (Fe²⁺), which is more soluble and bioavailable. - It counteracts the inhibitory effects of phytates and other dietary inhibitors. - This is an **absorption enhancer, not an inhibitor**. *Oxalate* - **Oxalate** (oxalic acid), found in foods like spinach, rhubarb, and beet greens, can also **interfere with iron absorption** by forming insoluble complexes with iron and other minerals. - However, oxalate is a **less potent inhibitor** compared to phytates, and its primary effect is on calcium absorption. - While it does reduce iron bioavailability, **phytates remain the more clinically significant inhibitor** of iron absorption.
Internal Medicine
2 questionsWhich type of anaemia is seen in vitamin B12 deficiency?
A 40-year-old male presents with fever and abdominal pain and is diagnosed with HIV and TB. What is the most appropriate sequence of treatment?
FMGE 2019 - Internal Medicine FMGE Practice Questions and MCQs
Question 181: Which type of anaemia is seen in vitamin B12 deficiency?
- A. Dimorphic anemia
- B. Microcytic anemia
- C. Macrocytic anemia (Correct Answer)
- D. Normocytic anemia
Explanation: ***Macrocytic anemia*** - Vitamin B12 is essential for **DNA synthesis**, and its deficiency leads to impaired nuclear maturation and delayed cell division in erythroid precursors, resulting in abnormally large red blood cells called **megaloblasts**. - This impaired maturation process leads to the production of **macrocytic red blood cells** (high MCV) which are also often prematurely destroyed, contributing to the anemia. *Dimorphic anemia* - This term describes the presence of **two distinct red cell populations**, typically microcytic and macrocytic, which can occur with combined deficiencies such as iron and vitamin B12. - While vitamin B12 deficiency primarily causes macrocytic anemia, dimorphic anemia is not its standalone feature unless accompanied by another deficiency. *Microcytic anemia* - Characterized by **abnormally small red blood cells** (low MCV), typically seen in conditions like **iron deficiency anemia** or thalassemia. - Vitamin B12 deficiency causes large red blood cells, thus ruling out microcytic anemia. *Normocytic anemia* - Red blood cells are of **normal size** (normal MCV) but are reduced in number, often seen in conditions like **anemia of chronic disease** or acute blood loss. - Since vitamin B12 deficiency directly impacts red blood cell size by causing megaloblastic changes, normocytic anemia is not the primary presentation.
Question 182: A 40-year-old male presents with fever and abdominal pain and is diagnosed with HIV and TB. What is the most appropriate sequence of treatment?
- A. First ATT and then ART
- B. ATT only
- C. First ART and then ATT
- D. ATT followed by ART within 2-8 weeks (Correct Answer)
Explanation: ***ATT followed by ART within 2-8 weeks*** - This sequence is crucial for patients with co-infection of **HIV and TB**. Initiating **anti-tuberculous treatment (ATT)** first is vital to control the active TB infection, which can be rapidly fatal [2]. - Subsequently, starting **antiretroviral therapy (ART)** within 2-8 weeks (typically 2-4 weeks after ATT in patients without CNS TB) helps to restore the immune system and prevent other opportunistic infections, but delaying it slightly reduces the risk of **IRIS (Immune Reconstitution Inflammatory Syndrome)** [1]. *First ATT and then ART* - While starting ATT first is correct, this option is too vague regarding the timing of ART initiation. - The specific window of 2-8 weeks (or 2-4 weeks without CNS TB) is important to balance TB treatment efficacy and mitigate **IRIS risk** [1]. *ATT only* - This approach is incorrect as it fails to address the underlying HIV infection, which would lead to continued immune decline and increased morbidity and mortality. - ART is essential for improving prognosis and reducing viral load in HIV-infected individuals. *First ART and then ATT* - Initiating ART before ATT in co-infected patients with active TB can worsen the TB condition due to **IRIS**, which can be severe and life-threatening [1]. - ART can cause a rapid immune reconstitution and paradoxical worsening of symptoms or presentation of subclinical TB [1].
Obstetrics and Gynecology
1 questionsBacterial vaginosis is caused by all except
FMGE 2019 - Obstetrics and Gynecology FMGE Practice Questions and MCQs
Question 181: Bacterial vaginosis is caused by all except
- A. Coccobacillus
- B. Mobiluncus
- C. Proteus (Correct Answer)
- D. Gardnerella
Explanation: ***Proteus*** - **Proteus** species are commonly associated with **urinary tract infections (UTIs)** and wound infections, not typically with bacterial vaginosis. - The presence of **Proteus** in vaginal flora is generally considered an opportunistic infection rather than a causative agent of BV. *Coccobacillus* - **Coccobacillary bacteria**, such as **Gardnerella vaginalis**, are primary organisms contributing to the polymicrobial shift that defines bacterial vaginosis. - The disruption of normal lactobacilli dominance allows for the overgrowth of these specific anaerobic and facultative organisms. *Mobiluncus* - **Mobiluncus species** are curved, rod-shaped anaerobic bacteria frequently found in high numbers in women with bacterial vaginosis. - They are considered key anaerobic bacteria involved in the microbial imbalance characteristic of BV. *Gardnerella* - **Gardnerella vaginalis** is the most commonly isolated bacterium in bacterial vaginosis and is considered the primary initiating organism. - While BV is polymicrobial, **Gardnerella's** overgrowth is central to the diagnostic criteria and pathogenesis.
Pediatrics
2 questionsA 3-month-old baby presents with fever and respiratory rate of 60/min. The baby is irritable but feeding well. There is no stridor, no chest indrawing, and no convulsions. What is the diagnosis?
Treatment of choice used in nocturnal enuresis is:
FMGE 2019 - Pediatrics FMGE Practice Questions and MCQs
Question 181: A 3-month-old baby presents with fever and respiratory rate of 60/min. The baby is irritable but feeding well. There is no stridor, no chest indrawing, and no convulsions. What is the diagnosis?
- A. Pneumonia (Correct Answer)
- B. Very severe pneumonia
- C. Severe pneumonia
- D. No Pneumonia
Explanation: ***Pneumonia*** - A respiratory rate of 60 breaths per minute in a 3-month-old infant meets the **WHO criteria for fast breathing**, which is the primary indicator for diagnosing **pneumonia** in this age group. - The absence of chest indrawing, stridor, or convulsions means this falls under **pneumonia**, not **severe** or **very severe pneumonia**. *Very severe pneumonia* - This would be diagnosed if there were **danger signs** such as inability to feed, lethargy, or convulsions, which are explicitly stated as absent. - Presence of **stridor** in a calm child or **severe malnutrition** would also suggest very severe pneumonia, none of which are mentioned. *Severe pneumonia* - This classification requires the presence of **chest indrawing** or **stridor** in a child, which are noted as absent in the clinical presentation. - While the child has fast breathing, the lack of additional severe signs distinguishes it from severe pneumonia. *No Pneumonia* - The presence of **fast breathing** (respiratory rate of 60 in a 3-month-old) is a clear sign of respiratory distress indicating **pneumonia**, according to WHO guidelines. - If the child had a normal respiratory rate and no other signs of respiratory illness, this option might be considered.
Question 182: Treatment of choice used in nocturnal enuresis is:
- A. Bed alarms (Correct Answer)
- B. Trazodone
- C. Fluoxetine
- D. Imipramine
Explanation: ***Bed alarms*** - **Bed alarms** are the **first-line, non-pharmacological treatment (TOC)** for nocturnal enuresis, working through classical conditioning to train the child to wake up when urination begins. - They have a high success rate and durable response once treatment is completed. *Trazodone* - **Trazodone** is an antidepressant primarily used for **insomnia** and depression; it is not indicated for the treatment of nocturnal enuresis. - It works by modulating serotonin reuptake and blocking alpha-1 adrenergic receptors, with a different mechanism of action than treatments for enuresis. *Fluoxetine* - **Fluoxetine** is a Selective Serotonin Reuptake Inhibitor (SSRI) primarily used to treat **depression, anxiety disorders**, and OCD. - It is not a recommended treatment for nocturnal enuresis and does not address the underlying physiological mechanisms. *Imipramine* - **Imipramine** is a tricyclic antidepressant that has been used for nocturnal enuresis, but it is **not the treatment of choice** due to potential side effects and the availability of safer, more effective options. - It works by anticholinergic and alpha-adrenergic effects to increase bladder capacity and arousal, but its use is often limited by its adverse effect profile.
Pharmacology
2 questionsWhich of the following is a carbonic anhydrase inhibitor?
Which of the following anti-epileptic drugs has the highest teratogenic potential?
FMGE 2019 - Pharmacology FMGE Practice Questions and MCQs
Question 181: Which of the following is a carbonic anhydrase inhibitor?
- A. Hydrochlorothiazide
- B. Mannitol
- C. Furosemide
- D. Acetazolamide (Correct Answer)
Explanation: ***Acetazolamide*** - Acetazolamide is a classic example of a **carbonic anhydrase inhibitor**, primarily used as a diuretic and for managing **glaucoma** and **altitude sickness**. - It works by inhibiting the enzyme **carbonic anhydrase** in the **proximal renal tubule**, reducing bicarbonate reabsorption and thus promoting diuresis. *Hydrochlorothiazide* - Hydrochlorothiazide is a **thiazide diuretic** that acts on the **distal convoluted tubule** to inhibit the reabsorption of sodium and chloride. - It is not a carbonic anhydrase inhibitor. *Mannitol* - Mannitol is an **osmotic diuretic** that works in the **proximal tubule** and **descending limb of Henle's loop** by creating an osmotic gradient. - It is not a carbonic anhydrase inhibitor and functions by drawing water into the renal tubule, leading to increased urine output. *Furosemide* - Furosemide is a **loop diuretic** that acts on the **thick ascending limb of the loop of Henle** by inhibiting the Na+-K+-2Cl- cotransporter. - It is one of the most potent diuretics but does not inhibit carbonic anhydrase.
Question 182: Which of the following anti-epileptic drugs has the highest teratogenic potential?
- A. Carbamazepine
- B. Phenytoin
- C. Valproate (Correct Answer)
- D. Lamotrigine
Explanation: ***Correct: Valproate*** - **Valproate has the highest teratogenic potential** among all anti-epileptic drugs, with a **10-20% risk of major congenital malformations** - **Neural tube defects** (spina bifida) occur in **1-2% of exposed pregnancies**, which is 10-20 times higher than the general population - Other significant risks include **cardiac malformations, craniofacial abnormalities**, and **neurodevelopmental disorders** (autism spectrum disorder, reduced IQ) - **Fetal valproate syndrome** is a recognized clinical entity - Current guidelines strongly recommend **avoiding valproate in women of childbearing potential** unless no alternatives exist *Incorrect: Carbamazepine* - Has teratogenic risks but significantly **lower than valproate** (2-5% risk of major malformations) - Associated with **neural tube defects** (0.5-1% risk, lower than valproate) - Considered a safer alternative when valproate must be avoided *Incorrect: Phenytoin* - Causes **fetal hydantoin syndrome** with characteristic features: craniofacial anomalies, nail/digital hypoplasia, growth restriction, and developmental delay - Teratogenic risk is **moderate** (approximately 5-10% risk of major malformations) - Risk is significant but **lower than valproate** *Incorrect: Lamotrigine* - Considered **one of the safest anti-epileptic drugs** during pregnancy - Low teratogenic risk with **major malformation rate of 2-3%** (close to baseline population risk) - Slight increased risk of **oral clefts** at higher doses - **Preferred choice** for women of childbearing potential requiring anti-epileptic therapy
Physiology
1 questionsPR interval in ECG shows?
FMGE 2019 - Physiology FMGE Practice Questions and MCQs
Question 181: PR interval in ECG shows?
- A. Atrial depolarization and conduction delay (Correct Answer)
- B. Conduction through AV node
- C. Delay in ventricular depolarization
- D. Delay in ventricular repolarization
Explanation: ***Atrial depolarization and conduction delay*** - The **PR interval** is measured from the **beginning of the P wave** to the **beginning of the QRS complex**. - It represents the **complete time** for the electrical impulse to travel from the SA node through the atria, the AV node, the Bundle of His, and bundle branches until ventricular depolarization begins. - This includes two major components: 1. **Atrial depolarization** (represented by the P wave) 2. **Conduction delay** through the AV node and His-Purkinje system (the isoelectric segment after the P wave) - **Normal PR interval**: 0.12-0.20 seconds (120-200 ms) - The **AV nodal delay** is the longest component, allowing atrial contraction to complete before ventricular contraction begins. *Conduction through AV node* - While **AV nodal conduction** is an important component of the PR interval, this option is **incomplete**. - The PR interval begins with the **P wave** (atrial depolarization), which occurs before the impulse reaches the AV node. - Stating only "conduction through AV node" ignores the atrial depolarization component that is also part of the PR interval. *Delay in ventricular depolarization* - **Ventricular depolarization** is represented by the **QRS complex**, not the PR interval. - The PR interval *ends* when ventricular depolarization begins (start of QRS). *Delay in ventricular repolarization* - **Ventricular repolarization** is represented by the **T wave** on an ECG. - This occurs much later in the cardiac cycle and is not related to the PR interval.
Radiology
1 questionsWhich of the following typically results in the maximum radiation exposure?
FMGE 2019 - Radiology FMGE Practice Questions and MCQs
Question 181: Which of the following typically results in the maximum radiation exposure?
- A. Chest X ray
- B. IV pyelography
- C. PET CT (Correct Answer)
- D. Barium Enema
- E. X-ray abdomen
Explanation: ***PET CT*** - **PET CT (Positron Emission Tomography-Computed Tomography)** combines the radiation from both a PET scan (using radiotracers like FDG) and a CT scan, resulting in the highest typical radiation exposure among the listed options. - The integration of functional (PET) and anatomical (CT) imaging, while providing comprehensive diagnostic information, significantly increases the total absorbed dose (~20-30 mSv). *Chest X-ray* - A **chest X-ray** involves a very low dose of radiation (~0.1 mSv), making it one of the imaging modalities with the least radiation exposure. - Due to its low dose and widespread use, the benefits of chest X-rays in diagnosing pulmonary and cardiac conditions far outweigh the minimal radiation risk. *IV pyelography* - **Intravenous pyelography (IVP)**, or intravenous urography, uses X-rays and contrast dye to visualize the urinary tract, delivering a moderate radiation dose (~3-5 mSv). - While higher than a standard X-ray, its dose is significantly lower than that of complex combined imaging like PET-CT. *Barium Enema* - A **barium enema** involves multiple X-ray images of the large intestine after administering barium contrast, leading to a moderate to high radiation dose (~8-15 mSv). - The series of exposures required to adequately visualize the entire colon contributes to a higher cumulative dose compared to single-shot X-rays.