Reproducibility of protected specimen brush and bronchoalveolar lavage conserved at 4 degrees C for 48 hours.
OBJECTIVE
Protected specimen brush (PSB) and bronchoalveolar lavage (BAL) are proposed in combination to optimize antimicrobial treatment. Nevertheless, they are only validated for immediate laboratory processing. This study was therefore conducted to determine whether 48 h conservation at a mere 4 degrees C enables good culture reproducibility for both PSB and BAL.


METHODS
Prospective study, evaluation of a conservation procedure for PSB and BAL, from February 1994 to February 1995, in the 12 bed ICU of a general hospital (938 beds).


METHODS
Ninety-nine PSB and 86 BAL samples, obtained from 100 bronchoscopic procedures, were analyzed. Thresholds were 10(3) and 10(4) cfu/ml for PSB and BAL, respectively.


RESULTS
Qualitative comparison between the immediate and 48 h procedures were, for PSB, specificity 100%, sensitivity 78%, positive predictive value 100%, negative predictive value 84% and overall accuracy 90%; and for BAL: 100%, 89%, 100%, 89% and 94%. Lowered 10(2) and 10(3) cfu/ml thresholds at the 48 h procedure for PSB and BAL reduce the false negatives from 10 to 3 and 5 to 1, respectively. Microorganism results were comparable for PSB and BAL ( r = 0.63 and 0.67), especially for the most resistant strains: Staphylococcus, Enterobacteriaceae and Pseudomonas. However, there was a decrease in the Neisseria and Haemophilus group ( p < 0.01).


CONCLUSIONS
There is a good culture reproducibility for both PSB and BAL after 48 h conservation at 4 degrees C, especially with lowered thresholds; this technique is therefore appropriate for routine use.
Service de Réanimation Polyvalente, Centre Hospitalier de Meaux, Saint Faron, 6-8 rue Saint Fiacre, 77104 Meaux, France. xforceville@invivo.edu
Xavier
X
Forceville
Alain
A
Fiacre
Frederic
F
Faibis
Pierre
P
Lahilaire
Marie-Claude
MC
Demachy
Alain
A
Combes
D000328:Adult; D000368:Aged; D001419:Bacteria / Q000145:classification; D018893:Bronchoalveolar Lavage; D003428:Cross Infection / Q000175:diagnosis / Q000382:microbiology*; D005260:Female; D005602:France; D006801:Humans; D007362:Intensive Care Units; D008297:Male; D008875:Middle Aged; D018410:Pneumonia, Bacterial / Q000175:diagnosis / Q000382:microbiology*; D011446:Prospective Studies; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013048:Specimen Handling / Q000379:methods* / Q000706:statistics & numerical data; D013696:Temperature