An unusual case of gross hematuria with acute renal failure: question

Excerpt

A previously fit and healthy 15-year-old boy presented with a 4-day history of dark urine, reduced urine output and bilateral flank pain. He had no past medical history of note and was not on any long-term medication. He was alert, interactive and warm and well perfused without any evidence of peripheral oedema. On admission his weight was 65.9 kg and height 172 cm. His body temperature was measured at 36.8°C, respiratory rate at 18 breaths/min, heart rate 68 beats/min, normal jugular venous pressure and blood pressure of 108/68 mmHg. Although both his tonsils were slightly inflamed they did not have any visible pus. There was no associated lymphadenopathy or organomegaly. Systemic examination was unremarkable except for the presence of mild bilateral flank tenderness. Additionally, there was history of a severe sore throat infection 2 weeks previously that had resulted in a review at his local Accident & Emergency department. Investigations including a throat swab performed at the local hospital at the time had failed to identify any obvious pathology and also confirmed normal renal function with a plasma creatinine at 76 μmol/l. …