Histopathologic and dermoscopic features of 42 cases of folliculitis decalvans: A case series

BACKGROUND

Folliculitis decalvans (FD) is a form of inflamed primary cicatricial alopecia (PCA). FD is classified as a neutrophilic PCA; however, only a few previous studies have described its histopathology, including the assessment of systematically evaluated and quantified follicular changes in horizontally sectioned biopsy specimens with clinical and dermoscopic findings of the early and advanced stages.

OBJECTIVE

We aimed to clarify the histopathologic and dermoscopic features of early and advanced active stage FD.

METHODS

We conducted a case series study of 42 patients with FD by dermoscopy and both horizontally and vertically sectioned biopsy specimens.

RESULTS

The histopathologic findings of the early-stage lesions included loss of sebaceous glands; interfollicular acanthosis; and fibrosis with depressed, fused follicular infundibula showing thickened interfollicular keloid-like areas with tufted hairs on dermoscopy. Active lesions showed a greater number of hair clusters, clefting, and fused infundibula with dense inflammation predominantly in the upper follicles. Neutrophil-predominant infiltrates were observed in fewer than half of the patients, including those with early-stage lesions.

LIMITATIONS

This was a retrospective study.

CONCLUSION

FD has the features of mixed-cell PCA. The features of early-stage FD are thickened interfollicular keloid-like areas with tufted hairs and loss of sebaceous glands.

Adipose tissue transplant in recurrent folliculitis decalvans

Folliculitis decalvans is a rare clinical disorder classified as primary neutrophilic scarring alopecia with a slight preference for the male gender. Here, we report the use of autologous fat transplantation as a source of stem cell therapy for hair re-growth assisted by inflammatory action of the fat itself in a female patient. The patient underwent adipose transplantation in April and September 2017. After treatments, the patient had no new pustules and no longer had pain or burning sensation in the affected area. The hair has re-grown at the periphery area of alopecia appearing stronger and shinier.