Acute interstitial nephritis in a patient taking tienilic acid.

Acute interstitial nephritis in a patient taking tienilic acid A patient taking the uricosuric diuretic tienilic acid or ticrynafen (2,3-dichloro-4-(2-thienyl-carbonyl) phenoxyacetic acid)-marketed as Selacryn, (Smith, Kline and French Laboratories 62698) developed acute renal failure due to acute allergic interstitial nephritis. Case report A 61-year-old housewife of Lithuanian extraction had been attending the nephrology hypertension clinic at the Royal Melbourne Hospital for 16 years. She had mild essential hypertension controlled by chlorothiazide 0-5 g twice daily and was also receiving thioridazine 50mg daily. She entered a double-blind cross-over trial comparing tienilic acid (250 mg daily) with hydrochlorothiazide (50 mg daily). After a four-week placebo phase she started on active treatment (retrospectively noted to have been with hydrochlorothiazide) for 12 weeks. During this phase her renal function was normal (serum creatinine concentration 0 08 mmol/l (0 9 mg/100 ml)) but she had mild hyperuricaemia (serum uric acid concentration 0 53 mmol/l (9 mg/100 ml)). After 16 weeks treatment was crossed over to tienilic acid. Nine days later her renal function was much impaired. Her serum creatinine concentration was 0 70 mmol/l (7 9 mg/100 ml) and her serum uric acid concentration >070 mmol/l (13-9 mg/100 ml). At this time she was mildly hypertensive (blood pressure 162/92 mm Hg) and complained of nausea, vomiting, and anorexia. Percutaneous renal biopsy showed acute tubular necrosis, interstitial oedema, and a heavy interstitial cellular infiltrate in which eosinophils were predominant. Although the infiltration was patchy the changes were interpreted as those of an acute hypersensitivity interstitial nephritis. Tienilic acid was stopped. Renal function improved spontaneously, returning to normal six weeks later (serum creatinine 0-08 mmol/l (0*9 mg/ 1 00 ml). Comment Tienilic acid, an orally active diuretic with uricosuric properties, is an effective antihypertensive in cases of mild-to-moderate hyper-tension.' Acute renal failure within hours of giving the drug has been reported and has usually been attributed to acute urate nephropathy.2 Some cases of acute renal failure may be precipitated during dehydration , particularly at cross-over periods from thiazide diuretics to tienilic acid and in the presence of hyperuricaemia. A reaction is described characterised by loin pain, abdominal pain, nausea, vomiting , and mild fever. Oliguria and acute renal failure may intervene, but is usually reversible.3 Renal biopsy in some cases has shown an unusual accumulation of vacuoles of a lysosomal type in the proximal tubules.4 No uric acid crystals are seen in the urinary sediment of such …