Minocycline‐induced cutaneous pigmentation

A 76‐year‐old man receiving long‐term prednisone therapy for rheumatoid arthritis had a four‐part intertrochanteric fracture after a fall. The patient underwent an open reduction with internal fixation and dynamic hip screw placement. Two months later, when the patient presented with significant pain and difficulty ambulating, radiographs revealed dissociation of the compression screw from the femoral head. At the time of removal of failed hardware, a total hip replacement procedure was aborted when intraoperative findings were consistent with infection. Thorough irrigation and debridement were performed, with placement of antibiotic‐impregnated cement spacers. One month after a 4‐week course of intravenous cefazolin, the patient underwent left total hip arthroplasty. Intraoperative cultures grew methicillin‐resistant Staphylococcus aureus and Corynebacterium jeikeium . A 4‐week course of intravenous vancomycin was followed by long‐term antibiotic suppression with long‐term minocycline (100 mg twice daily). Six months after starting minocycline, the patient noticed a blue‐gray discoloration of the forearms. During the next 4 months, the pigmentation progressed considerably. He was admitted to Mayo Clinic for a myocardial infarction. Three‐vessel coronary artery disease was discovered, necessitating bypass grafting. Before surgery, dermatology was consulted. A main concern of the primary service was the discoloration representing ecchymoses in a surgical candidate with a possible bleeding diathesis. Cutaneous examination revealed slate gray, ill‐defined patches in the preauricular, flank, upper thigh, and shoulder areas. Similar patches coalesced on the upper and lower extremities ( Fig. 1). There was no scleral or mucous membrane involvement. Histologically, minocycline pigmentation with pigment‐laden macrophages and free dermal pigment in the papillary and superficial reticular dermis stained positive with Prussian blue and Fontana‐Masson ( Fig. 2). Minocycline was discontinued, and the patient was started on trimethoprim‐sulfamethoxazole double strength once daily for long‐term antimicrobial therapy. 1Minocycline‐induced slate gray discoloration of the (a) arms and (b) shins2Pigment‐laden macrophages and free dermal pigment. (Hematoxylin‐eosin; original magnification ×600)