A 28-year-old man presents with a painless indurated ulcer at the coronal sulcus for 10 days. He has bilateral, non-tender, rubbery inguinal lymphadenopathy. Dark-field microscopy of serum from the lesion base shows motile spirochetes. VDRL is reactive (1:8). Which histopathological feature is most characteristic of primary syphilitic chancre?
- A Suppurative granuloma with central necrosis
- B Intraepidermal vesicle with acantholysis
- C Dense plasma cell infiltrate with obliterative endarteritis ✓
- D Palisading granuloma with caseous necrosis
Correct answer: C. Dense plasma cell infiltrate with obliterative endarteritis
Explanation
The hallmark histopathology of syphilitic chancre is dense perivascular plasma cell infiltrate with obliterative endarteritis (endothelial swelling and fibrosis of vessel walls). This endarteritis is responsible for the induration of the chancre. Granulomas with caseous necrosis are seen in tuberculosis. Suppurative granuloma is characteristic of LGV/cat-scratch disease. Acantholysis is a feature of pemphigus.
Reference: Neena Khanna Illustrated Synopsis of Dermatology & STD, 6th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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