Stimulated sweating in chronic renal failure.

should be preceded by an ECG to exclude those patients with atrio-ventricular block grades II and III. Sulphamethoxazole, hypoalbuminaemia, crystalluria, and renal failure Sulphamethoxazole is an active component of co-trimoxazole. We describe two patients who developed renal failure after receiving this drug. Case reports Case 1-A 31-year-old woman developed generalised peritonitis secondary to a pyosalpinx, which had been excised. Endotoxic shock ensued, which was treated with penicillin, gentamicin, and metronidazole for seven days with good effect. She then became febrile and was started on co-trimoxazole intravenously, 1 ampoule (5 ml co-trimoxazole in 150 ml 0 9",, saline) infused over 30 minutes. The drug was given 12-hourly, and within 36 hours her urine output had fallen in association with haematuria and profound crystalluria. Co-trimoxazole was stopped but she went into complete renal failure and, despite acute haemodialysis, died. Case 2-A 24-year-old man presented with peritonitis eight days after being stabbed in the abdomen causing three colonic perforations, which had been oversewn. He was given the same antibiotics as in case 1, but with little effect, and intravenous co-trimoxazole was begun (same regimen as in case 1). Within 48 hours he went into acute renal failure. Mannitol (20",) 300 ml was administered and co-trimoxazole stopped. This resulted in a pronounced diuresis, and within 14 days renal function returned to normal. Comment Both these patients were septicaemic and hypoproteinaemic (serum albumin concentrations 16 and 18 g 1 respectively). In both cases serum samples taken before co-trimoxazole treatment were recovered, which permitted in-vitro sulphamethoxazole-binding studies using 15C-sulphamethoxazole. With normoalbuminaemic serum 24-35', of sulphamethoxazole is protein bound.' In these two patients, however, only 2",, and 36",, of the drug was bound. Neither patient was dehydrated when co-trimoxazole was instituted, and in both cases renal function was normal (serum creatinine 97 2 and 79 6 !smol 1 (1 1 and 0 9 mg,100 ml) respectively). Presumably by virtue of the hypoalbuminaemia, and possibly due to the presence of penicillin and metronidazole in the serum acting as competitive binders, sulphamethoxazole was unable to bind, so that nearly all the drug was free (unbound). This is a similar finding to that reported in kwashior-kor serum, in which only 4-7",, of the drug was bound (serum albumin 22 g 1).' As only the free component of a drug is filtered by the kidneys it may be assumed that in these two patients crystalluria ensued secondary to the massive load …