Detection of bacterial DNA in acute and chronic cholecystitis

The incidence of bacterbilia in cholelithiasis remains controversial. The positivity of cultures ranges from 0 to 73 per cent. The aim of this study was to employ the polymerase chain reaction (PCR) to detect bacterial DNA in gallbladder bile extracted during elective laparoscopic cholecystectomy, and to compare PCR findings with those of bile culture.

Bile samples from 84 laparoscopic cholecystectomies were collected for culture and PCR analysis.

Positive results for bacterbilia were found in 42 (50 per cent) of 84 patients by PCR but in only 16 patients (19 per cent) by culture (P < 0.001). Agreement between the two methods was seen in 44 samples (52 per cent), which were negative in 35 cases. Pathological examination showed chronic cholecystitis in 69 cases (82 per cent) and acute cholecystitis in 15 (18 per cent). Thirty-three (48 per cent) of the patients with chronic cholecystitis were PCR positive but only ten (14 per cent) were culture positive (P < 0.001). Only culture results correlated with findings on pathological examination (P = 0.033).

PCR is more sensitive in detecting bacterial contamination of gallbladder bile in cholecystitis than conventional culture. The clinical relevance of this high sensitivity remains unclear.