44-Year-Old Man With Anemia, Thrombocytopenia, and Acute Kidney Injury

Abstract

44-year-old man presented with a 3-month history of progressive generalized weakness, polyarthralgia, polymyalgia, fatigue, unintentional 11 kg (13%) weight loss, and vision loss. His medical history is significant for hypothyroidism, melanoma in remission, spongiotic dermatitis that resolved with prednisone, Raynaud disease, and recently diagnosed monoclonal gammopathy of undetermined significance (MGUS). His ongoing medications include levothyroxine (75 ug), lisinopril (20 mg), omeprazole (40 mg), prednisone (40 mg), sulfamethoxazoletrimethoprim (400 to 80 mg), sumatriptan (50 mg as needed), and zolpidem (5 mg as needed). He denies recent diarrhea, fevers, chills, night sweats, easy bruising, hypertension, or bleeding. Family history was notable for psoriasis but negative for other autoimmune or renal disease. On exam, the patient was afebrile with a heart rate of 63 beats/ min, respiratory rate 14 breaths/min, blood pressure 131/88 mm Hg, and oxygen saturation 97% on room air. He was alert, orientated, and not in acute distress. Cardiovascular exam revealed an irregularly irregular pulse without murmurs, gallops, or rubs. Lungs were clear to auscultation with good air entry bilaterally. Skin exam was negative for rash, sclerodactyly, or calcinosis. Fundoscopic exam was significant for bilateral beading of retinal vessels, intraretinal hemorrhages, and cotton wool spots.Laboratory studies revealed the following results (reference ranges in parentheses): hemoglobin level, 11.3 g/dL (13.7 to 17.5 g/ dL); mean corpuscular volume (MCV), 95.5 fL (80 to 100 fL); white blood cell count, 12.8Â10 9 /L (3.4 to 9.6Â10 9 /L); platelet count, 65Â10 9 /L (135 to 317Â10 9 /L); blood urea nitrogen, 41 mg/dL (6 to 24 mg/dL);