Case Number : Case 750 - 1st May Posted By: Guest

Chronic folliculitis with ruptured follicle and secondary granulomatous reaction to released hair shaft structures. The lesion is associated with dense plasma cell collections demonstrating beautifully Russel bodies. Plasma cells are commonly encountered in association with chronic folliculitis, do not think the whole pattern of the plasma cell proliferation fits with associated plasma cell granuloma, though it is a possibility. Will do PAS to exclude fungus as a cause of this folliculitis (although age is less likely), and will do kappa and lambda staining to be sure of the polyclonal nature of the plasma cell proliferation and to exclude plasmacytoma.

Ruptured follicular cyst

[u]Chronic folliculitis. I am not concerned about neoplastic conditions but would order special stains to exclude fungal and bacterial infections.[/u]

I go with acneiform syphilis due to granulomatous plasma cell-rich perifolliculitis. Alternatively, late phase of acne keloidalis nuchae due to suggestion of scarring.

Granulomatous folliculitis and associated inflammation rich in plasma cells suggestive of infectious aetiology.

I favor a chronic lesion of [b]acne keloidalis nuchae[/b], in the context of a papular occipital lesion.

The central follicle shows: tapering exclamation-point features in the more superficial, dysmorphic hair shaft, polytrichia, concentric lamellar fibroplasia and atrophy extending deep into the infundibulum. There are numerous naked hair shaft foreign body granulomas (some with partially degraded hair shafts). There are numerous plasma cells and fibrosis, with absence of significant acute inflammatory component.

I called this acne keloidalis nuchae.