IMPROVED DETECTION OF BACTERIAL-GROWTH IN CONTINUOUS AMBULATORY PERITONEAL-DIALYSIS EFFLUENT BY USE OF BACT ALERT FAN BOTTLES/

Culture-negative peritonitis is a major complication for patients on c ontinuous ambulatory peritoneal dialysis (CAPD) and precludes organism -specific therapy, The aim of the present study was to compare inocula tion of 10 ml of CAPD effluent into BacT/Alert blood culture bottles ( FAN [fastidious antimicrobic neutralizing], BacTAlert aerobic [BTA], a nd BacT/Alert anaerobic [BTAn] bottles) to our conventional method of using 50 mi of concentrated CAPD effluent to inoculate peptone broth b ottles (ED bottles) and MacConkey agar and blood agar medium (BA-MAC), The FAN, BTA, and BTAn bottles were monitored automatically in the Ba cT/Alert blood culture instrument, A total of 207 CAPD effluents were studied, and in 97 bacteria were detected by at least one method, Comp ared to BTA bottles (79 of 97; 81.4%), BTAn bottles (78 of 97; 80.4%), and ED bottles (88 of 97; 90.7%), the single best broth medium for de tecting bacterial growth in CAPD effluents was the FAN bottle (90 of 9 7 effluents; 92.8%), A total of 125 bacterial species were detected by any method, and the majority (91.8%) of CAPD effluents were infected with a single species, A combination of FAN and BTAn bottles detected 111 of 125 (88.8%) of all organisms, whereas a combination of ED bottl es and BA-MAC detected 107 of 125 (85.6%) of all organisms, One or mor e organisms that would have been completely missed by the conventional method with ED bottles and BA-MAC were detected in 18 CAPD effluents. Of these 18 CAPD effluents, 6 showed no growth by the conventional me thod with ED bottles and BA-MAC. On the basis of our data, the most se nsitive and least labor intensive method was direct inoculation of 10 mi of CAPD effluent into a FAN bottle and a BTAn bottle, which could b e automatically monitored by the BacT/Alert blood culture instrument, On the basis of case definitions for peritonitis, the sensitivities an d specificities of the methods with FAN and BTAn bottles and with ED b ottles and BA-MAC were 81.1 and 98.8% and 74.5 and 96.5%, respectively .