Supplementary Material for: Peritonitis in peritoneal dialysis - when to consider acute pancreatitis? Case report and mini-review

Introduction: Acute pancreatitis is an infrequent but challenging cause of peritonitis in peritoneal dialysis (PD). Presentation is often indistinguishable from infectious peritonitis, interpretation of pancreatic enzymes is not straight-forward and multiple etiologies need to be considered. Case presentation: A 74 years old PD patient presented with cloudy dialysate and subtle symptoms of malaise and abdominal pain. WBC was 26.000 /µL, CRP 250 mg/L and dialysis effluent contained 1047 leucocytes /µl (90% polymorphs). Infectious peritonitis was presumed and antibiotic treatment started. However, dialysate cultures remained negative, effluent leucocyte count remained high and clinical condition deteriorated. Abdominal ultrasound was unremarkable (pancreas not visible). Acute pancreatitis was diagnosed by elevated lipase level (serum: 628 U/L, dialysis fluid: 15 U/L) and CT scan. Disentangling etiological factors was challenging. The patient had gallstones, consumed alcoholic beverages, was recently on doxycycline and dialyzed with icodextrin. In addition, PD treatment itself may have been a contributory factor. Antibiotic therapy was stopped and PD temporarily suspended. Systemic and effluent markers of inflammation took 4 weeks to normalize. The patient did not regain his usual state of health until several weeks after discharge. Follow-up CT scan showed considerable pancreatic sequelae. Conclusion: Acute pancreatitis is an important cause of PD peritonitis. Negative dialysate cultures and unsatisfactory clinical response should trigger evaluation for acute pancreatitis and its multiple potential causes, including PD treatment itself. Serum lipase levels >3 times ULN and elevated dialysis fluid lipase can be expected. Timely performance of imaging is advisable. Prognosis can be poor and close monitoring is recommended.