Hereditary forms of folliculitis, such as follicular eczema (generally classified under "atopic dermatitis"), and the deeper forms of inflammatory folliculitis that involve the entire follicular structure, such as folliculitis decalvans, occur most commonly in blacks. Folliculitis may also be seen as a secondary infection in conditions such as eczema, scabies, and excoriated insect bites. It is more commonly found in patients who are diabetic, obese, or immunocompromised.

One school of thought considers thisas a subset of Central Centrifugal Cicatricial Alopecia (CCCA). These authors purport that the pustules seen in it are a manifestation of either bacterial superinfectio or an intense immune response to degenerating follicular components. According to their studies, if inflamed but non-pustular areas of affected individuals are sent for biopsy, the histological findings are similar to those seen in Follicular Degeneration syndrome or pseudopelade. As it broadly overlaps with pseudopelade and Follicular Degeneration syndrome, these authors believe that folliculitis decalvans represents the same basic pathological process.

Folliculitis is not always caused by S aureus. Other forms of folliculitis may be caused by organisms acquired in hot tubs or by irritation, friction, chemicals, steroids, or fungi. In addition, therapeutically recalcitrant folliculidities, such as the herpes simplex infections or eosinophilic pustular folliculitis, may be seen in patients with acquired immunodeficiency syndrome (AIDS).

Folliculitis decalvans treatment can mimic classic folliculitis, acne necrotica, lichen planopilaris, discoid lupus erythematosus, and dissecting cellulitis (also called perifolliculitis capitis abscedens et suffodiens). Other than that, all forms of treatment have their own side effects, and benefits of treatment must be evaluated against the consequences of the drugs. Rifampin causes red staining of bodily secretions including tears. Zinc at high dosage levels competes with copper metabolism and can result in severe refractory anemia and neutropenia, a hematological disorder.

Diagnosis of the condition is based on clinical, microbiological, histo-pathological and laboratory features. Grouped follicular pustules as seen in folliculitis decalvans are not seen in ordinary folliculitis or acne necrotica. Dissecting cellulitis can be distinguished easily as early pustules and papule formation develop immediately into dermal nodules. In addition, folliculitis decalvans does not display the sinus tract formation in histological skin biopsies, a characteristic typical of dissecting folliculitis.