We investigated whether spontaneous bacterial peritonitis in cirrhosis is a recurrent process and attempted to identify possible predictors of recurrence in 75 consecutive cirrhotics who had recovered from a first episode of spontaneous bacterial peritonitis between January, 1981 and December, 1984 and who were followed closely throughout their illness (follow-up period 10 +/- 13 months; mean +/- S.D.). Thirty-eight patients (51%) developed one or more episodes of spontaneous bacterial peritonitis during follow-up, the probability of recurrence (Kaplan-Meier's method) being 43% at 6 months, 69% at 1 year and 74% at 2 years. Twenty-three variables (age, sex, etiology of cirrhosis, standard liver and renal function tests and characteristics of the first spontaneous bacterial peritonitis) were analyzed as possible predictors of recurrence of spontaneous bacterial peritonitis. In univariate analysis (curves of Kaplan-Meier compared with Mantel-Cox's method), serum bilirubin greater than 4 mg per dl, prothrombin less than or equal to 45% and protein concentration in ascitic fluid less than or equal to 1 gm per dl were significantly (p less than 0.05) associated with a high risk or recurrence of spontaneous bacterial peritonitis. In multivariate analysis (Cox multiple regression model), only ascitic fluid protein concentration (p = 0.005) and prothrombin activity (p = 0.009) were found to be independent predictors of recurrence of spontaneous bacterial peritonitis. Fifty-nine patients (79%) died during follow-up, 18 of them (31%) secondary to spontaneous bacterial peritonitis. The 1-year survival probability in the whole series of patients was 38%.(ABSTRACT TRUNCATED AT 250 WORDS)