Minocycline-Induced Agranulocytosis Presenting as Ecthyma Gangrenosum

Abstract

A 51-year-old female with a history of rheumatoid arthritis was admitted for progressive fevers, chills and malaise. Five weeks prior, she started minocycline for an RA exacerbation. Two weeks after starting minocycline she developed an abscess on her right ankle that was treated at an urgent care facility with ceftriaxone and trimethoprim-sulfamethoxazole. She had minimal improvement so was switched to clindamycin. She developed additional abscesses on her right ankle and right axilla and spiking fevers so she was treated with incision and drainage under general anesthesia. Routine blood work obtained prior to surgery revealed severe neutropenia (0.74 103/ul) and the patient was urgently referred to the emergency department.  Skin biopsy was obtained on admission and revealed ulceration, necrosis, acute and chronic inflammation, vasculitis with vascular thrombosis and rod-shaped bacteria in blood vessel walls and lumina consistent with ecthyma gangrenosum. The following day tissue and blood cultures confirmed the growth of Pseudomonas aureginosa. 

Bone-marrow biopsy showed decreased granulopoiesis and hematopoiesis, and a diagnosis of minocycline-induced agranulocytosis presenting as ecthyma gangrenosum was made.  The patient had dramatic improvement with appropriate antibiotic therapy, discontinuation of minocycline and initiation of filgrastrim. She has remained healthy without recurrence for 17 months.