5th July 2024

A 70-year-old gentleman is admitted with generalised weakness and dark discolouration of his urine

A 70-year-old gentleman is admitted with generalised weakness and dark discolouration of his urine. He was recently started on clarithromycin by his GP for fevers and a cough. His PMH is significant for T2DM, IHD, HTN & COPD. His regular medications are Aspirin, Bisoprolol, Ramipril, Atorvastatin, Gliclazide, Metformin, Tiotropium Inhaler and a PRN salbutamol inhaler. He is allergic to penicillin. Investigations show: Hb 140 g/L (115-165), WBC 6.6×10⁹/L (4-11), Neutrophils 5.2×10⁹/L (2-8), Platelets 325×10⁹/L (150-400), Na 143 mmol/L (135-145), K 4.9 mmol/L (3.5-5), Urea 9.6mmol/L (2.5-7.5), Creatinine 190 μmol/L (60-110). Urine dipstick showed 1+ protein, 3+ blood.

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