Unveiling a Shared Precursor Condition for Acne Keloidalis Nuchae and Primary Cicatricial Alopecias

Clinical, Cosmetic and Investigational Dermatology
Open Access

Clinical Summary

View source

What was studied

Retrospective study of 41 consecutive men with acne keloidalis nuchae (AKN) seen June–December 2022 at a single clinic, assessing normal‑appearing scalp ≥5 cm from lesions via trichoscopy‑guided biopsies for perifollicular infundibulo‑isthmic lymphocytoplasmic infiltrates and fibrosis (PIILIF).

Key findings

All 41/41 had trichoscopy signs in normal‑appearing scalp and histologic PIILIF; 96% lacked vellus/miniaturized hairs. Coexisting folliculitis decalvans occurred in 9/41 (22%); PIILIF was often labeled clinically as seborrheic dermatitis (diagnosed in 18/41, 44%; treated in 21/41, 51%).

Study limitations

Retrospective, single AKN specialty clinic without a control cohort, limiting generalizability; small numbers for some subsets (e.g., FD histology n=4; immunohistochemistry subsets).

Clinical implications

In men with AKN, examine the entire scalp with trichoscopy and biopsy suspicious “normal” areas: PIILIF was universal in this series and often mimicked seborrheic dermatitis. Management should include treating scalp‑wide inflammation, not only visible AKN lesions.