Gram-negative infections in patients with folliculitis decalvans: a subset of patients requiring alternative treatment.

Background Folliculitis decalvans is a neutrophilic cicatricial alopecia whose etiology remains unknown. It is frequently associated with staphylococcal infections. We aimed to determine the rate of gram-negative infections in patients with folliculitis decalvans. Methods A retrospective chart review was performed of patients with biopsy-proven folliculitis decalvans seen at a tertiary hair referral center. The results of bacterial cultures were evaluated. Subjects were determined to have no infection, gram-positive infections, gram-negative infections, or mixed infections. Results Thirty-nine subjects were included in the study. Ninety-three cultures were performed. The majority of cultures were positive for staphylococci. Eleven patients (28%) had gram-negative infections of the scalp. Gram-negative infections comprised one-third of all cultures (33%). Conclusion We present the largest cohort of folliculitis decalvans patients with gram-negative infections, suggesting the need for routine bacterial cultures in patients who are not responsive to standard anti-staphylococcal antibiotics. Awareness of the incidence of these infections may lead to better therapeutic outcomes.