Case Studies

 Case 9.1 Poststreptococcal glomerulonephritis

A 9-year-old boy was admitted as an emergency with puffiness of the face, eyes and trunk. A week previously he had complained of a sore throat. On examination, he was mildly pyrexial (temperature 37.5°C) and hypertensive (BP 170/110). There was periorbital and scrotal oedema. His urine showed proteinuria, haematuria and red cell casts. He was anaemic (Hb 107g/l) with a normal white-cell count and differential. A throat swab grew normal flora but antibodies to streptococcal antigens were present in high titre: antistreptolysin O titre 1600iu/ml (normal <300iu/ml); antihyaluronidase titre 1/2048; and anti-deoxyribonuclease B titre 1/1360. Serum complement studies done 3 days after admission showed a very low C3 (0.10g/l; NR 0.8-1.40) and a normal C4 (0.23g/l; NR 0.2-0.4). His creatinine clearance was 46ml/min, serum albumin 29g/l and urinary protein excretion 1.5g/day.

These findings were typical of poststreptococcal glomerulonephritis and so renal biopsy was not performed. As anticipated, the serum complement returned to normal in 4 weeks, accompanied by disappearance of the proteinuria and hypertension, although a small amount of microscopic haematuria persisted. The prognosis is good. An unusual feature of this case was the degree of hypertension.