A 58-year-old woman, originally from Somalia, presented to our Dermatology clinic for assessment of a relapsing course of generalized pruritic eruption. Her comorbidities included type 2 diabetes, hypertension, dyslipidemia, non-alcoholic fatty liver disease, peripheral artery disease, and immune thrombocytopenic purpura. She reported that her skin lesions improved with sun exposure and worsened in the winter. Previous treatments included only calcipotriol and betamethasone dipropionate ointment to which she had minimal improvement. On physical examination, there were widespread scaly erythematous papules and plaques, affecting 10% of her body surface area (BSA). Halobetasol propionate cream was started while awaiting histopathology results that finally confirmed a diagnosis of psoriasis.
As a treatment for her severe psoriasis (baseline BSA 10%, Psoriasis Area Severity Index (PASI) of 10.2; Dermatology Life Quality Index (DLQI) of 15) and patient preference against a biologic therapy at this time, apremilast 30 mg twice daily was initiated. After 16 weeks of treatment, her psoriasis significantly improved (BSA of 2%, PASI of 2.6). However, after 4 months of treatment, the dosing had to be reduced to 30 mg daily due to gastrointestinal side effects. Following this dose modification, her psoriasis worsened (BSA of 15%; PASI of 12.8), and to prepare her for the next therapeutic option, we performed a pre-immunosuppressive work-up that included blood test, TB skin test, and chest X-ray (CXR).
At this pre-biologic screening, she was diagnosed with LTB by the infectious diseases team. She had an abnormal CXR, and positive TB skin test and QuantiFERON-TB Gold without any symptoms of active TB. A computed tomography (CT) chest scan was ordered for further assessment, showing a small region of chronic inflammatory reaction in the posterior area of the left upper lobe and a superimposed granuloma. She was treated with rifampicin 600 mg daily for 4 months, and much to our surprise, her psoriasis completely resolved within 2-3 months of treatment. In addition, her psoriasis has remained clear 1 year after stopping rifampicin.