Life-threatening hyperchloraemic acidosis in an azotaemic patient with normal serum creatinine

150 mmol/l, potassium (K+) 3.6 mmol/l and chloride(Cl−) 126.3 mmol/l. The anion gap (Na+−(HCO3−A 70-year-old man was admitted with pronounced +Cl−)) was increased (20 mmol/l). Blood urea wasdyspnoea and a 2 week history of progressively 201 mg/dl, and creatinine 1.0 mg/dl. Haemoglobin,worsening diarrhoea and diminished urinary volume. white blood cell count, platelet count, C-reactive pro-The diarrhoea was described as watery stools without tein, aminotransferases, phosphate, lactate, and bloodblood or mucus and was not ameliorated by loperam- sugar were normal. Stool cultures were negative.ide. Anuria developed 2 days before admission. Fever, Urinanalyses were not performed because of anuria.nausea, and abdominal or ank pain were absent. Ultrasonography showed an empty bladder with noIn 1995 the patient had undergone abdominoperineal signs of hydronephrosis; however, uid-lled loops ofrectum resection and sigmoid colostomy as treatment bowel were visualized. A cystogram revealed a largefor non-metastatic adenocarcinoma of the distal stulous tract between the urinary bladder and smallrectum with an intermediate stage of diVerentiation intestine (Figure 1).(pT3N3M0, R0-resection). The patient received com- The patient received uid substitution, bicarbonatebined adjuvant treatment with pelvic radiotherapy and potassium infusions, and surgical treatment was(total dose 50.4 Gy delivered in a fractionated fashion) planned. Two days later the diarrhoea ceased and urineand 5-uoruracil chemotherapy. Urinary retention due owed through the bladder catheter. The acidosis andto neurological damage, as assessed by cystometry, uraemia reversed rapidly. Surgical treatment withdeveloped as a complication of surgery. The patient excision of the stula and direct closure was performed.performed intermittent self-catheterization three times Microscopic examination of the stulous tract revealeda day. Two years later an abdominal computed tomo- late-stage radiation injury with signs of chronicgraphy scan showed evidence of local recurrence and inammation and vascular damage with intimal b-metastatic disease in the liver. Palliative therapy with rosis. No signs of malignancy were detected.endotoxin (