Abstract

Dermatologic procedures disrupt the skin barrier and predispose individuals to cutaneous infection. Most procedures have a low wound infection rate, even with common pathogens. However, infections have been reported, mainly due to environmental and patient risk factors, with an increase in non-tuberculous mycobacteria. Mycobacterium abscessus is the most common culprit, frequently associated with contaminated traumatic skin wounds and post-surgical soft tissue infections. Herein, we describe a post-surgical mycobacterial infection in a patient treated for pilomatricoma. Literature review showed this is the first case of mycobacterial infection following the excision of pilomatricoma.

A 57-year-old man of Indian origin presented with a cystic lesion on his right elbow. Pathological examination of the excised lesion revealed a morphological stage 3 pilomatricoma. The patient's postoperative course was complicated by swelling and itching at the excision site. The area was treated with multiple intralesional Kenalog for presumed hypertrophic scar without improvement. The area was re-excised to rule out recurrence of pilomatricoma recurrence. The histopathology revealed a small follicular cyst surrounded by cicatricial dermis containing multiple suppurative granulomata. No residual pilomatricoma was present. Special stains for fungal organisms were negative. An acid-fast stain showed acid-fast bacilli with the granulomata. 

One association between pilomatricoma and mycobacterial infection is reported, where pilomatricoma was secondarily infected by mycobacterium. However, cutaneous mycobacterial infection is common in post-surgical excisions of dermatological conditions due to poor surgical and post-surgical antiseptic care, wound contamination, immunosuppression, and demographical factors. In our case, at least two factors contributed: localized immunosuppression and the patient demographics.