The eruption is often resistant to treatment and may persist for months to years before resolution. Recurrent remissions and exacerbations can occur in some patients.
L73.8 – Other specified follicular disorders
81856009 – Disseminate infundibulo-folliculitis
Differential Diagnosis & Pitfalls
- Atopic dermatitis (follicular or papular eczema) – History of atopy and seasonal variation, and better response to topical steroids.
- Folliculitis – Pustules and erythema.
- Lichen nitidus – Papules are nonfollicular, shiny, and flat-topped.
- Keratosis pilaris – Central keratin plugs, preferentially affects extensor aspects of arms and legs, and often has seasonal variation.
- Lichen spinulosus – Central keratin plugs and papules occur in circumscribed plaques.
- Pityriasis rubra pilaris – Central keratin plugs, papules spread cephalocaudally, scaly orange-red plaques (with "islands of sparing"), and palmoplantar keratoderma.
- Phrynoderma (vitamin A deficiency) – Central keratin plugs, history of intestinal malabsorption or anorexia nervosa.
- Darier disease – Follicular and nonfollicular papules coalesce to form larger papillomatous plaques with seborrheic distribution, and characteristic nail and oral findings.