The aminoglycoside antiseptic that is used as a first-line anti-TB drug is?

ISRO 2024

Pharmacology

Easy

Appeared in: ISRO 2024

Explanation

Streptomycin is an aminoglycoside antibiotic that is classified as a first-line agent for treating tuberculosis (TB).
Historically, it was the first antibiotic found to be effective against Mycobacterium tuberculosis.
Its mechanism of action involves irreversibly binding to the 30S ribosomal subunit of the bacteria, which inhibits protein synthesis and leads to bacterial cell death.
While newer all-oral regimens are now often preferred for drug-sensitive TB, Streptomycin remains a key first-line injectable agent in specific treatment protocols and for certain types of TB.

Option A: Tobramycin is not used as a first-line anti-TB drug. Its primary indication is for treating serious infections caused by gram-negative bacteria like Pseudomonas aeruginosa and Proteus species.
Option B: Amikacin is not a first-line drug for TB. It is a broader-spectrum aminoglycoside reserved as a second-line agent for treating multidrug-resistant tuberculosis (MDR-TB).
Option D: Kanamycin, similar to Amikacin, is a second-line anti-TB drug. Its use is limited to resistant cases due to its significant ototoxicity and nephrotoxicity.

Clinical Relevance

Nursing practice connection: Knowing Classification of anti-tuberculosis drugs, specifically aminoglycosides helps nurses interpret findings accurately and avoid errors in routine assessment, medication administration, and patient teaching.
The most critical nursing responsibility when administering any aminoglycoside, including Streptomycin, is monitoring for toxicity.
Nurses must perform baseline and periodic assessments of hearing (audiometry) and balance to detect ototoxicity early. Any patient report of tinnitus, vertigo, or hearing loss requires immediate attention.
Monitoring renal function through blood tests (BUN, serum creatinine) and urine output is essential to prevent irreversible kidney damage (nephrotoxicity).

How to Approach the Question

First, break down the question. It asks for a specific drug that fits two criteria: it must be an aminoglycoside AND a first-line anti-TB drug.
Recall the standard first-line anti-TB drugs, often remembered by the mnemonic RIPE or RIPES: Rifampicin, Isoniazid, Pyrazinamide, Ethambutol, and Streptomycin.
Next, review the options provided: Tobramycin, Amikacin, Streptomycin, and Kanamycin. All of these belong to the aminoglycoside class.
Compare the list of first-line drugs with the given options. Streptomycin is present in both lists.
Confirm the status of the other options. Recall or deduce that Amikacin and Kanamycin are reserved for resistant TB (second-line), and Tobramycin is primarily for other types of bacterial infections, not TB.
This process of elimination and direct matching confirms Streptomycin as the only option that meets both criteria.

Concept Tested & Keywords

Concept Tested: Classification of anti-tuberculosis drugs, specifically aminoglycosides.
Stem keywords: aminoglycoside, first-line, anti-TB drug
Lead-in keywords: is
Negative lead-in flag: false

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