Biochemistry
1 questionsA 36 year old man presents with decreased appetite, mouth soreness, diarrhoea and irritability. On examination he has a bright red tongue with a pigmented scaly rash around the neck. Which one of the following food items in his diet has a bearing on his disease?
UPSC-CMS 2025 - Biochemistry UPSC-CMS Practice Questions and MCQs
Question 81: A 36 year old man presents with decreased appetite, mouth soreness, diarrhoea and irritability. On examination he has a bright red tongue with a pigmented scaly rash around the neck. Which one of the following food items in his diet has a bearing on his disease?
- A. Wheat
- B. Fish
- C. Corn (Correct Answer)
- D. Rice
Explanation: ***Corn*** - A diet heavily reliant on **corn** (maize) as a staple lacking proper fortification or preparation can lead to **niacin (Vitamin B3) deficiency**, historically common in regions where corn was the primary dietary component. - The symptoms described—**decreased appetite, mouth soreness, diarrhea, irritability, bright red tongue (glossitis)**, and a **pigmented scaly rash around the neck (Casal's necklace)**—are classic manifestations of **pellagra**, a disease caused by niacin deficiency. *Wheat* - While wheat is a common dietary staple, it is not typically associated with classic pellagra symptoms like **Casal's necklace** or severe **glossitis** that point specifically to niacin deficiency. - Wheat-related issues usually involve **celiac disease** (gluten intolerance) or other sensitivities, presenting with different gastrointestinal and dermatological profiles. *Fish* - Fish is a good source of various nutrients, including some B vitamins, and is generally not associated with causing nutritional deficiencies like pellagra. - No symptoms described are typically linked to a diet rich in fish or lack thereof in a way that points to the given presentation. *Rice* - Rice can be a staple food, but a diet predominantly of polished rice can lead to **thiamine (Vitamin B1) deficiency** causing **beriberi**, which presents differently (e.g., neuropathy, heart failure). - It does not cause the characteristic dermatological signs of pellagra like **Casal's necklace**.
Community Medicine
1 questionsWhich one among the following vectors transmits the filaria *Loa loa*?
UPSC-CMS 2025 - Community Medicine UPSC-CMS Practice Questions and MCQs
Question 81: Which one among the following vectors transmits the filaria *Loa loa*?
- A. Cyclops
- B. Chrysops (Correct Answer)
- C. Simulium
- D. Culicoides
Explanation: ***Chrysops*** - **Deer flies** of the genus *Chrysops* are the **intermediate hosts** for *Loa loa*, transmitting the microfilariae when they bite. - These flies are typically found in the **humid rainforests of West and Central Africa**, where loiasis is endemic. *Cyclops* - *Cyclops* (copepods) are the **intermediate hosts** for **Dracunculus medinensis** (guinea worm) and **Diphyllobothrium latum** (fish tapeworm). - They are **freshwater crustaceans** and not involved in the transmission of filarial worms like *Loa loa*. *Simulium* - *Simulium* (blackflies) are the **vectors** for **Onchocerca volvulus**, which causes **onchocerciasis** (river blindness). - These flies breed in **fast-flowing rivers** and are known for their painful bites. *Culicoides* - *Culicoides* (biting midges) are the **vectors** for **Mansonella perstans** and **Mansonella streptocerca** filarial worms, as well as some viral diseases. - They are distinct from the *Chrysops* flies that transmit *Loa loa*.
Dermatology
2 questionsWhich one of the following statements is correct regarding leprosy?
A 56 year old gardener presents with an ulcerative nodule with purulent discharge on his right index finger. He had a prick with a thorn, at the same site around a month back. Which one of the following infections is most likely?
UPSC-CMS 2025 - Dermatology UPSC-CMS Practice Questions and MCQs
Question 81: Which one of the following statements is correct regarding leprosy?
- A. Nose is the last site of involvement in lepromatous leprosy
- B. Type 1 Leprosy Reaction is also called erythema nodosum leprosum
- C. 'Lion face' appearance is seen in tuberculoid leprosy
- D. Type 2 Leprosy Reaction is an immune complex mediated syndrome also known as erythema nodosum leprosum (Correct Answer)
Explanation: ***Type 2 Leprosy Reaction is an immune complex mediated syndrome also known as erythema nodosum leprosum*** - **Type 2 Leprosy Reaction (ENL)** is indeed an **immune complex-mediated hypersensitivity reaction** seen in cases of **multibacillary leprosy**, primarily **lepromatous leprosy** patients undergoing treatment. - It presents with painful, tender, red subcutaneous nodules, often associated with fever, malaise, arthralgia, and neuritis due to the deposition of **antigen-antibody complexes**. *Nose is the last site of involvement in lepromatous leprosy* - The **nose** is actually one of the **earliest sites of involvement** in **lepromatous leprosy** due to the preference of *Mycobacterium leprae* for cooler tissues. - Initial nasal involvement can lead to nasal stuffiness, epistaxis, and, in advanced stages, destruction of cartilage leading to a **saddle nose deformity**. *Type 1 Leprosy Reaction is also called erythema nodosum leprosum* - **Erythema Nodosum Leprosum (ENL)** is **Type 2 Leprosy Reaction**, not Type 1. - **Type 1 Leprosy Reaction** (also known as **reversal reaction**) is a **delayed-type hypersensitivity reaction** that typically occurs in borderline forms of leprosy, characterized by inflammation of existing skin lesions and nerves. *'Lion face' appearance is seen in tuberculoid leprosy* - The **"lion face" appearance (leontiasis)** is a characteristic feature of **advanced lepromatous leprosy**, not tuberculoid leprosy. - It results from diffuse skin infiltration, thickening of facial skin, and nodule formation, leading to coarse, pendulous folds and a distorted facial appearance.
Question 82: A 56 year old gardener presents with an ulcerative nodule with purulent discharge on his right index finger. He had a prick with a thorn, at the same site around a month back. Which one of the following infections is most likely?
- A. Chromoblastomycosis
- B. Phaeohyphomycosis
- C. Mycetoma
- D. Sporotrichosis (Correct Answer)
Explanation: ***Sporotrichosis*** - This presentation, an **ulcerative nodule with purulent discharge** on a finger after a **thorn prick** in a gardener, is classic for **sporotrichosis** (rose gardener's disease). - The organism, *Sporothrix schenckii*, is found in soil, plants, and decaying vegetation and typically enters through **skin trauma**. *Chromoblastomycosis* - Characteristically presents with **verrucous (warty) plaques or nodules** that slowly enlarge; it does not typically show the ulcerative nodule with purulent discharge found here. - While it can be acquired through trauma, the **morphology of the lesions** differs from the described case. *Phaeohyphomycosis* - This is a broad term for infections caused by dematiaceous (pigmented) fungi that typically present as **subcutaneous cysts, abscesses, or nodules**, but the specific clinical picture of **lymphocutaneous spread** following trauma is less characteristic than sporotrichosis. - The lesions tend to be more **encapsulated or abscess-like** rather than the ulcerative, purulent nodule described. *Mycetoma* - Mycetoma presents as a **chronic, localized, progressively destructive infection** of the skin, subcutaneous tissue, fascia, and bone, often characterized by **swelling, draining sinuses, and grains** (microcolonies of the causative organism). - While it can be acquired via trauma, the typical presentation is much more **extensive and chronic** than the initial ulcerative nodule described.
Internal Medicine
1 questionsWhich of the following is the most favourable prognostic parameter in Bell's palsy?
UPSC-CMS 2025 - Internal Medicine UPSC-CMS Practice Questions and MCQs
Question 81: Which of the following is the most favourable prognostic parameter in Bell's palsy?
- A. Pain behind the ear
- B. Incomplete paralysis in the first week (Correct Answer)
- C. Denervation in EMG after 10 days
- D. Mild CSF lymphocytosis
Explanation: ***Incomplete paralysis in the first week*** - The most favorable prognostic factor in Bell's palsy is **incomplete facial paralysis** at presentation or within the first week [1]. - This suggests a less severe nerve injury, making **full recovery** more likely [1]. *Pain behind the ear* - While common in Bell's palsy, **retroauricular pain** is not a specific prognostic indicator for recovery. - It can occur in both mild and severe cases and does not correlate with the degree of paralysis or recovery outcome. *Denervation in EMG after 10 days* - Evidence of **denervation on electromyography (EMG)** after 10 days indicates significant nerve damage and is a **poor prognostic sign**. - This suggests that the nerve fibers have degenerated, leading to a longer and less complete recovery. *Mild CSF lymphocytosis* - **Mild CSF lymphocytosis** can be found in some cases of Bell's palsy, particularly if the cause is thought to be viral. - However, it is not a direct prognostic factor for the extent of facial nerve recovery or the overall outcome of the palsy.
Pharmacology
5 questionsWhat is the antidote for belladonna poisoning?
Which one of the following prevents gastrointestinal absorption of thallium?
A 45 year old farmer came with accidental consumption of a pesticide. He complained of frequent urination and excessive salivation. Which one of the following toxidromes is most likely to be associated with this poisoning?
Consider the following regarding salicylate poisoning : I. Arterial pH of 7.25 , anion gap of 18 mmol / L II. Arterial pH of 7.25 , anion gap of 10 mmol / L III. pCO2 of 20 mm Hg IV. pCO2 of 48 mm Hg Which disturbance is likely to be encountered?
Which one of the following groups of drugs is ineffective against gram positive bacteria?
UPSC-CMS 2025 - Pharmacology UPSC-CMS Practice Questions and MCQs
Question 81: What is the antidote for belladonna poisoning?
- A. Atropine
- B. Amitriptyline
- C. Physostigmine (Correct Answer)
- D. Flumazenil
Explanation: ***Physostigmine*** - **Physostigmine** is a **reversible acetylcholinesterase inhibitor** that increases acetylcholine levels at the muscarinic and nicotinic receptors. - This effectively counteracts the **anticholinergic effects** of belladonna, which contains atropine and scopolamine, by overcoming the competitive blockade. *Atropine* - **Atropine** is the primary toxic component in belladonna, acting as a **muscarinic acetylcholine receptor antagonist**. - Administering atropine would worsen the existing anticholinergic toxidrome, making it a contraindicated treatment. *Amitriptyline* - **Amitriptyline** is a **tricyclic antidepressant** and has significant **anticholinergic properties** itself. - Using amitriptyline would exacerbate rather than treat the symptoms of belladonna poisoning due to its similar mechanism of action. *Flumazenil* - **Flumazenil** is an **antagonist of benzodiazepine receptors** and is used to reverse benzodiazepine overdose. - It has no effect on the muscarinic receptor blockade caused by belladonna alkaloids and would not be effective in this poisoning.
Question 82: Which one of the following prevents gastrointestinal absorption of thallium?
- A. Calcium carbonate
- B. Potassium permanganate
- C. Penicillamine
- D. Prussian blue (Correct Answer)
Explanation: ***Prussian blue*** - **Prussian blue** (ferric hexacyanoferrate) acts as an ion exchanger in the gastrointestinal tract, binding to thallium and preventing its absorption. - This complex of thallium and Prussian blue is then **excreted in the feces**, reducing systemic toxicity. *Calcium carbonate* - **Calcium carbonate** is an antacid primarily used to neutralize stomach acid or as a calcium supplement. - It does not specifically bind to or prevent the absorption of **thallium**. *Potassium permanganate* - **Potassium permanganate** is a strong oxidizing agent sometimes used for gastric lavage in certain poisonings. - It does not form a stable, non-absorbable complex with **thallium** to prevent its gastrointestinal uptake. *Penicillamine* - **Penicillamine** is a chelating agent used for heavy metal poisoning, such as copper (in Wilson's disease) or lead. - While it can chelate some metals, its primary mechanism involves forming soluble complexes that are excreted renally, rather than directly preventing **gastrointestinal absorption** of thallium.
Question 83: A 45 year old farmer came with accidental consumption of a pesticide. He complained of frequent urination and excessive salivation. Which one of the following toxidromes is most likely to be associated with this poisoning?
- A. Adrenergic
- B. Cholinergic (Correct Answer)
- C. Hypnotic
- D. Serotonergic
Explanation: ***Cholinergic*** The patient's symptoms of frequent urination and excessive salivation, along with accidental pesticide consumption, are classic signs of **organophosphate poisoning**, which falls under the **cholinergic toxidrome** [1, 2]. This toxidrome is characterized by excessive stimulation of the **cholinergic system**, leading to symptoms memorized by the acronyms **SLUDGE** (Salivation, Lacrimation, Urination, Defecation, Gastrointestinal upset, Emesis) and **DUMBBELS** (Diarrhea, Urination, Miosis, Bradycardia, Bronchorrhea, Emesis, Lacrimation, Salivation) [1]. *Adrenergic* The adrenergic toxidrome is associated with sympathetic overactivity, leading to symptoms like **tachycardia**, **hypertension**, **mydriasis**, agitation, and hyperthermia. These symptoms are opposite to the parasympathetic overactivity observed in this patient. *Hypnotic* The hypnotic toxidrome typically presents with **CNS depression**, including **sedation**, **respiratory depression**, **bradycardia**, and **hypotension**. This toxidrome does not match the patient's symptoms of excessive salivation and frequent urination. *Serotonergic* The serotonergic toxidrome (serotonin syndrome) is characterized by a triad of mental status changes, autonomic hyperactivity (e.g., **tachycardia**, **hypertension**, hyperthermia), and neuromuscular abnormalities (e.g., **hyperreflexia**, clonus). The patient's presentation does not align with these hallmark features.
Question 84: Consider the following regarding salicylate poisoning : I. Arterial pH of 7.25 , anion gap of 18 mmol / L II. Arterial pH of 7.25 , anion gap of 10 mmol / L III. pCO2 of 20 mm Hg IV. pCO2 of 48 mm Hg Which disturbance is likely to be encountered?
- A. II and III
- B. II and IV
- C. I and III (Correct Answer)
- D. I and IV
Explanation: ***I and III*** - Salicylate poisoning typically presents with a **mixed acid-base disorder** consisting of primary **respiratory alkalosis** and primary **metabolic acidosis with an increased anion gap** [1]. - A pH of 7.25 with an anion gap of 18 mmol/L (normal range 8-12 mmol/L) indicates **metabolic acidosis with an increased anion gap**, while a pCO2 of 20 mmHg (normal range 35-45 mmHg) indicates **respiratory alkalosis** [2]. *II and III* - An anion gap of 10 mmol/L is within the normal range, which is inconsistent with the **metabolic acidosis with increased anion gap** expected in salicylate poisoning [1]. - While pCO2 of 20 mmHg indicates respiratory alkalosis, the normal anion gap makes this combination less likely for salicylate poisoning. *II and IV* - An anion gap of 10 mmol/L is within the normal range, which does not reflect the typical **anion gap metabolic acidosis** seen in salicylate poisoning. - A pCO2 of 48 mmHg indicates respiratory acidosis, which is generally not the primary respiratory disturbance in salicylate poisoning; rather, **respiratory alkalosis** due to direct stimulation of the respiratory center is more characteristic [1]. *I and IV* - While an anion gap of 18 mmol/L is consistent with **anion gap metabolic acidosis**, a pCO2 of 48 mmHg indicates respiratory acidosis. - The classic picture of salicylate poisoning includes **respiratory alkalosis** due to direct stimulation of the respiratory center, not respiratory acidosis [1].
Question 85: Which one of the following groups of drugs is ineffective against gram positive bacteria?
- A. Glycopeptides
- B. Fluoroquinolones
- C. First generation cephalosporins
- D. Monobactams (Correct Answer)
Explanation: Monobactams - **Monobactams**, such as **aztreonam**, have a narrow spectrum of activity primarily targeting aerobic **Gram-negative bacteria** [1]. - They lack significant activity against **Gram-positive organisms** and **anaerobes** due to differences in cell wall structure and penicillin-binding proteins (PBPs) [1]. *Glycopeptides* - **Glycopeptides**, like **vancomycin**, are highly effective against a wide range of **Gram-positive bacteria**, including **MRSA** (methicillin-resistant *Staphylococcus aureus*) [3]. - They inhibit cell wall synthesis by binding to the D-Ala-D-Ala precursor, which is crucial for **Gram-positive cell wall integrity**. *Fluoroquinolones* - **Fluoroquinolones** are broad-spectrum antibiotics with activity against both **Gram-positive** and **Gram-negative bacteria** [4]. - While some newer agents (*e.g., levofloxacin, moxifloxacin*) have enhanced **Gram-positive coverage**, older agents (e.g., **ciprofloxacin**) are less potent against Gram-positives [4]. *First generation cephalosporins* - **First-generation cephalosporins** (e.g., **cefazolin**, **cephalexin**) exhibit good activity against many **Gram-positive bacteria**, including **staphylococci** and **streptococci** [2]. - They are commonly used for infections caused by **Gram-positive organisms** and as surgical prophylaxis [2].