Pathology · single question
What is the best NON-INVASIVE method for diagnosis of Mucous Membrane Pemphigoid?
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Correct answer: C. Nikolsky sign
- A. Brush biopsy samples oral epithelial cells and is used for oral cancer screening — it is not appropriate for MMP diagnosis.
- B. Incisional biopsy with direct immunofluorescence is the DEFINITIVE (but invasive) diagnostic method for MMP — not non-invasive.
- C. The NIKOLSKY SIGN is a non-invasive clinical test for vesiculobullous diseases: applying lateral pressure with a finger to perilesional mucosa causes sloughing/separation of the epithelium. POSITIVE Nikolsky sign indicates fragility of the epithelial-connective tissue junction, characteristic of MMP (and pemphigus). It is a quick, non-invasive bedside diagnostic test. Definitive diagnosis requires INCISIONAL BIOPSY with direct immunofluorescence.
- D. Exfoliative cytology (smear) is used for fungal infections or viral cytopathic effects — it is not the best screening test for MMP.