Pseudocysts in acute nonalcoholic pancreatitis - Incidence and natural history

Epidemiological studies on pancreatic pseudocysts are retrospective analyse s on alcoholic patients. The aims of this study were to investigate the inc idence, natural history, and predictors of the appearance and disappearance of pancreatic fluid collections and pseudocysts after nonalcoholic acute p ancreatitis. We carried out a prospective cohort study in a series of 926 p atients with acute pancreatitis. Pancreatic fluid collections or pseudocyst s were treated only after complications. We studied pancreatic fluid collec tions from 83 patients (8.9%): 48 of whom developed pseudocysts (5.1%). Bot h were less frequent after biliary pancreatitis (P < 0.0001). In the first 60 days of follow-up, patients with fluid collections or pseudocysts showed more complications than spontaneous disappearance; two of them died. After the 60th day, spontaneous disappearance was more frequent, and at one year the cumulative incidence of complications and spontaneous disappearance wa s 36% and 56%, respectively. A total of 33 patients with fluid collection n eeded interventional treatment (surgery or percutaneous or endoscopic drain age). Pseudocysts that were small (<5 cm) or developed in the tail had a hi gher incidence of spontaneous disappearance: 22/24 (91.7%) and 11/12 (91.7% ), respectively. In conclusion, fluid collections and pseudocysts after non alcoholic pancreatitis have a low incidence of complications and mortality with a high rate of spontaneous disappearance. We suggest treating them onl y after complications.