‘Soybean sauce’ peritoneal dialysate

A 68-year-old woman with end-stage diabetic nephropathy undergoing continuous ambulatory peritoneal dialysis for 2 years was admitted for septic shock with coma, who was found hours earlier. Physical examination revealed an unconscious febrile woman with blood pressure of 84/ 49 mmHg. Blood tests showed a haemoglobin of 11.5 (normal 12–15) g/dL, white blood cell (WBC) count of 11.3 (normal 3.8–9.8) × 10/L with 82% of segmented neutrophils, high creatine kinase level of 3050 (normal 20–170) U/L, as well as elevated aspartate aminotransferase (198, normal 11–45 U/L) and alanine aminotransferase level (117, normal 7–50 U/L). The peritoneal dialysate was initially clear, but became reddish-brown (Figure 1A) with a red blood cell (RBC) count of 1/μL and WBC 12/μL at the next exchange several hours later, and progressed to ‘soybean sauce’-like (Figure 1B) on the second hospital day when the analysis demonstrated an occult blood reaction of 3+ by dipstick, RBC 14/μL, WBC 200/μL with neutrophils 83%, bilirubin 0.1 mg/dL, along with a serum haemoglobin of 10.5 g/dL. Despite intensive management with potent intravenous antibiotics and high-dose inotropic agents, the patient died on the third hospital day. The dialysate kept the same appearance without precipitation even after being stored for 7 days. The abundant peritoneal dialysable [1] myoglobins from progressive rhabdomyolysis precipitated by longterm immobilization and profound septic shock [2] in our patient are favoured to have caused the ‘soybean sauce’ dialysate because of the strongly positive occult blood reaction with only 14 RBC/μL in the dialysate. The nearly constant serum haemoglobin level and extremely low dialysate bilirubin level further convincingly excluded the possibility of intra-abdominal bleeding and bile leakage, respectively. The discoloured peritoneal dialysate by myoglobin is rarely described. Another interesting report is the ‘cola-coloured’ effusion in a peritoneal dialysis patient suffering from rhabdomyolysis with a dialysate myoglobin level of 20 406 μg/L [3].