Case Studies

 Case 5.6 Minocycline-induced systemic lupus erythematosus

A previously healthy 23-year-old woman was referred to a rheumatology clinic with a 4-month history of pain and swelling in the small joints of her hands associated with a blotchy rash over the bridge of her nose and over her knuckles. Examination revealed mild symmetrical synovitis in the hands and red scaly patches over her knuckles and face consistent with a photosensitive rash. Her blood pressure was normal and dipstick testing of her urine showed no blood or protein. Investigations showed a normal full blood count, urea and creatinine. Her erythrocyte sedimentation rate was significantly elevated at 43mm/h. Antinuclear antibodies were present at a titre of 1/1000 with a homogenous pattern. Antibodies to double-stranded DNA and extractable nuclear antigens were absent. A biopsy of the sun exposed skin was negative on a lupus band test. A diagnosis of mild SLE was made and she was treated with non-steroidal anti-inflammatory drugs and hydroxychloroquine. She was also given advice on protection from ultraviolet light.

Her symptoms failed to improve over the next 6 months and treatment with low-dose corticosteroids was considered. However, she refused to consider steroid treatment as she had read about side-effects and was concerned that this drug would cause her previously troublesome acne to return. At this point it transpired that she had been receiving treatment with daily low doses of the antibiotic minocycline for the last 4 years because of previously severe acne. She had not mentioned this previously as she had been taking this form of treatment for so long that she did not feel it could be relevant to her more recent problems. The minocycline was discontinued and the clinical and laboratory features of SLE disappeared over the next 6 months, confirming the revised diagnosis of minocycline-induced SLE. Her acne remained in remission with no treatment.