Summary: Two cases of histologically proven acute post-streptococcal glomerulonephritis presenting as congestive cardiac failure with normal blood pressure are reported. Proteinuria was not a finding. These features are discussed. Introduction The clinical hallmarks of acute nephritis are the abrupt onset of haematuria and proteinuria, accompanied by oliguria with oedema and hypertension. Recently we have seen a young woman with serologically and histologically proven acute post-streptococcal glomerulonephritis (PSGN) who had no proteinuria throughout her illness. Review of the records of 25 cases of biopsy-proven post-infectious glomerulonephritis presenting to the Department of Nephrology of the Royal Melbourne Hospital over 20 years revealed one similar case. Both cases are reported.Case reports Case 1: A 36-year-old woman suffered an influenza-like illness with high fever. Three days later she developed a reddish rash on the lower legs which settled over 48 hours. Over the next week she had aching in the wrists, ankles, knees and neck. For four days prior to admission she had severe headache and anorexia, and developed marked oedema of the face, arms and legs, associated with increased thirst and decrease in urine volume, which was not altered in colour.On examination, blood pressure was 125/80 mmHg, temperature 37.3°C, and weight was 9 kg above normal. The jugular venous pressure (JVP) was elevated; there was a fourth heart sound, ascites and oedema to the mid-thigh. Repeated routine urine dipstick testing showed no protein and a trace to one plus of blood; urine specific gravity was 1002.The chest X-ray showed interstitial pulmonary oedema with a normal heart size. ECG and echocardiogram were normal. Serum sodium was 129 mmol/l, potassium 5.0 mmol/l, albumin 39 g/l, creatinine 0.09 mmol/l and urea 9.1 mmol/l. A 24-hour urine collection of 1098 ml contained 46 mmol potassium, 33 mmol sodium, 0.04 g protein (normal <0.15 g) and the glomerular filtration rate using the 5tCr EDTA method was 66 ml/mm/1.73 m2 (normal 92-157). Urine microscopy showed 8000 leukocytes (WBC), 60 000 glomerular red cells (RBC) Fairley & Birch 1982) 12 000 hyaline and 20 000 red cell casts per ml. The haemoglobin was 10.0 g/dl, ESR 35 mm/h, and anti-DNase and antistreptolysin-o (ASO) titres of 1:360 suggested recent beta-haemolytic streptococcal infection. Immune complexes, autoantibodies, and hepatitis B antigen were negative and anti-DNA binding was normal. Both total complement and C3 were consistently depressed.Renal biopsy showed a diffuse proliferative and exudative endocapillary glomerulonephritis with mesangial and capillary loop staining for IgG, IgM, IgA, C3, Clq and fibrin on immunofluorescence.The oedema responded to bed rest, modest fluid restriction and oral frusemide. At no stage was the blood pressure elevated and the maximum urinary protein excretion was 0.20 g/day.Case 2: A 20-year-old woman presented with acute pulmonary oedema four weeks after a sore throat. Swelling of the feet, hands and face developed suddenly o...