Hyponatraemia induced by a combination of hydrochlorothiazide and triamterene.

Urological complications of renal transplantation are well recognised1 2 but, to our knowledge, this is the first case of ureteric obstruction resulting from a calculus in the donor kidney. The recipient's normal bone biochemistry and the time of presentation make it unlikely that the calculus arose de novo after surgery. Unless a calculus is particularly large it is unlikely to be recognised at retrieval surgery. Previous studies have emphasised the need for early detection in the management of the obstructed transplant ureter.3 The frequent use of an isotope renogram in preference to an intravenous urogram after transplantation may render early detection of such calculi more difficult.