Micro & Immunology · single question
A patient presents with a stellate (star-shaped) ulcer. What organism should be suspected?
Show answer and explanation
Correct answer: B. Mycobacterium tuberculosis
B) Mycobacterium tuberculosis — CORRECT.
Oral tuberculosis ulcers characteristically appear as irregular, stellate (star-shaped), painful ulcers with undermined edges, typically on the tongue or palate. They are pathognomonic of oral TB when combined with systemic symptoms (night sweats, weight loss, hemoptysis).
A) Syphilis: Primary syphilis produces a painless chancre (single, indurated); secondary syphilis causes "snail-track" ulcers — not stellate.
C) Candida: Appears as white plaques (pseudomembranous) or erythematous patches — not stellate ulcers.
D) HSV: Vesicles that rupture into small, clustered painful ulcers — not stellate.
Oral tuberculosis ulcers characteristically appear as irregular, stellate (star-shaped), painful ulcers with undermined edges, typically on the tongue or palate. They are pathognomonic of oral TB when combined with systemic symptoms (night sweats, weight loss, hemoptysis).
A) Syphilis: Primary syphilis produces a painless chancre (single, indurated); secondary syphilis causes "snail-track" ulcers — not stellate.
C) Candida: Appears as white plaques (pseudomembranous) or erythematous patches — not stellate ulcers.
D) HSV: Vesicles that rupture into small, clustered painful ulcers — not stellate.
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