A 55-year-old woman was referred to our ward for further evaluation of mark
ed hyperuricaemia and suspected tophi. On physical examination, huge subcut
aneous nodules were observed on the knee joints as well as a small nodule o
n the lateral side of the left sole. Blood chemistry showed marked hyperuri
caemia (0.85 mmol/l), hypokalaemia (2.7 mmol/l) and a mild degree of renal
insufficiency. Arterial blood gas analysis showed signs of metabolic alkalo
sis. Daily urinary uric acid excretion on a purine non-restricted diet was
8.9 mmol/day. Uric acid clearance and fractional uric acid clearance were 0
.8 ml/min and 2.6%, respectively. Plasma renin activity was 21.8 ng/ml/h, a
nd plasma angiotensin II and aldosterone concentrations were 61 and 121 pg/
ml, respectively. However, pressor response to an intravenous administratio
n of angiotensin II was normal. The urinary calcium to creatinine molar rat
io was 0.069, and serum magnesium concentration was normal to supranormal.
A biopsy of the subcutaneous nodule showed a typical appearance of tophus.
Based on these findings, the patient was diagnosed with an atypical case of
renal tubular hypokalaemic metabolic alkalosis, with marked hyperuricaemia
and tophi as the initial manifestations. So far, only four cases of Bartte
r's syndrome with gout and/or hyperuricaemia have been described in Japan.
This rare case is presented and its mechanism of hyperuricaemia discussed.