Evaluation of fine catheter aspiration cytology of the peritoneum as an adjunct to decision making in the acute abdomen.

Fine catheter aspiration cytology of the peritoneal cavity was performed successfully in 61 patients admitted with acute abdominal pain. Aspirates were examined microscopically and the percentage of neutrophils in the specimen counted. In patients in whom the clinical need for operation was certain (n = 25) all patients required surgery and the peritoneal neutrophil count was greater than 50 per cent. In patients in whom the clinical need for operation was uncertain (n = 36) 19 patients required operation: the peritoneal neutrophil count was greater than 50 per cent in 18 and in one patient with ectopic pregnancy fresh blood was aspirated. Of the 17 patients not requiring operation the peritoneal neutrophil count was less than 10 per cent in 15 and greater than 50 per cent in two patients (both had acute pelvic inflammatory disease). This study confirms peritoneal cytology as a useful adjunct to decision making in those patients with acute abdominal pain in whom the decision to operate is in doubt.