Nonbacterial, or sterile, folliculitis can arise from physical or chemical irritation.

Irritants include hair removal methods such as leg waxing, shaving, electrolysis, plucking or chemical depilatories, occlusive dressings, wearing tight clothing, and excessive sweating.

Nonbacterial folliculitis may also be related to working conditions, such as the use of greases or oils, and to the application of various cosmetics. Occasionally, secondary bacterial infection may occur.

Topical or systemic steroid treatment may lead to steroid-induced acne, which is actually a form of folliculitis.

Diagnosis of these conditions is aided by a history of potent topical or systemic steroid use (Fig. 16.13).

Eosinophilic pustular folliculitis (EPF), another form of sterile folliculitis, is typically intensely pruritic.

Presents in three clinical forms: (1) EPF in adults also called Ofuji disease, (2) AIDS-associated EPF, and (3) EPF of infancy which presents as recurrent grouped papulopustules most often noted on the scalp.

Lesions appear as recurrent crops of erythematous papules and papulopustules on “sebaceous” areas of skin and spontaneously resolve over 7 to 10 days (Fig. 16.14). Recurrences may occur every 3 to 4 weeks.

In all three forms there may be peripheral eosinophilia and histology will show eosinophils around the follicular infundibulum.

Tinea corporis of the lower legs may produce tinea folliculitis in women who shave their legs. The organism is introduced into the hair follicle by shaving.