VALUE OF GRAM STAIN OF CELL BLOCK MATERIAL FROM PERITONEAL-FLUID IN BACTERIAL PERITONITIS

OBJECTIVE: To determine the value of Gram's stain of cell blocks of pe ritoneal fluid for the diagnosis of bacterial peritonitis. STUDY DESIG N: The results of Gram's stain of 12 cases of culture-positive, frank bacterial peritonitis (FBP) and 11 cases of culture-positive spontaneo us bacterial peritonitis (SBP) were compared with 6 cases of culture-n egative frank sterile peritonitis and 21 cases of culture-negative spo ntaneous sterile peritonitis. RESULTS: For both FBP and SBP, Gram's st ain had low sensitivity (8% and 9%). Overall, the positive predictive value of Gram's stain for peritonitis ions 33%. Hematoxylin-eosin (HE) was just as sensitive but had a positive predictive value of 100%. CO NCLUSION: In cell block material of peritoneal fluid, Gram's stain is of little value except to further characterize organisms seen on HE.