Renal, Urology and Electrolytescommon
A 23-year-old man presents because his urine has turned dark brown, which he noticed this morning. Two days ago he developed a sore throat and runny nose, which are still present. His blood pressure is 138/88 mmHg and he is otherwise well; urinalysis shows blood 3+ and protein 1+, and serum creatinine is 98 micromol/L (60-110). He recalls a similar self-limited episode of dark urine during a head cold about 18 months ago. Which one of the following is the most likely diagnosis?