Case presentation
A 51-year-old Sudanese female was diagnosed with RA in 2018 based on the
EULAR classification of RA. She had a history of bilateral symmetrical
polyarthritis with involvement of small joints of the hands, both wrists
and shoulders; they are also associated with morning stiffness lasting
for two hours. She was treated successfully with methotrexate and
prednisolone and her disease remains in remission. A year ago, she
started to develop an itchy skin rash with pus involving her lower
extremities and abdomen. She had no fever, weight loss, skin rashes,
bowel symptoms, aphthous ulcers or hair loss. Currently, she has no
joint pain or extra-articular manifestations. Her systemic review was
unremarkable. The patient had hypertension for 5 years, her family
history revealed no history of connective tissue diseases. She is a
mother of 7 healthy children with no history of abortion. In terms of
drug history, she is on amlodipine 5 mg for hypertension. Her
musculoskeletal examination showed no synovitis, her skin examination
showed nodulopapular lesions affecting the extensor surfaces of the
lower extremities particularly on thighs and the lower part of the
abdomen with hyperpigmentation as shown in the figures (1, 2).
Laboratory tests revealed normal liver function test and renal function
test, C-reactive protein 12.9 (<5), Erythrocyte sedimentation
rate (ESR) is 70mm/hr (<15), normal urine analysis and blood
sugar level 98 mg/dl. With regards to Immunological studies: Rheumatoid
factor (RF) <8 (negative), anti-citrullinated peptide
antibodies (ACPA) <4(<20, negative) and Antinuclear
factor <1/80(negative). Hand X-ray demonstrated periarticular
osteopenia and the Chest x-ray was normal. Skin lesion biopsy showed
multiple foci of necrosis, mixed inflammatory infiltrates composed
mainly of neutrophils, hyperkeratosis and acanthosis and no evidence of
vasculitis. The biopsy findings were consistent with a diagnosis of
neutrophilic dermatosis fig (3, 4). The patient received topical and
systemic steroids for the skin lesion however, no significant
improvement was noticed, and then she was started on cyclosporin 100 mg
twice a day with close monitoring of the serum creatinine and blood
pressure, few weeks later her skin lesions and general condition showed
marked improvement.