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Aims: Evaluation of 16S PCR in addition to the standard culture to improve the pathogen detection rate in clinical specimens. Methods and Results: Microbiological culture and direct 16S PCR was performed on specimens from suspected prosthetic joint infection patients (cohort‐1) and on tissues and fluids from other normally sterile body sites (cohort‐2). Based on clinical and microbiological data, the detection rate for both methods was assessed, assuming no superiority of either 16S PCR or culture. In cohort‐1, 469 specimens were obtained. Culture was positive in 170 (36·2%) specimens, 16S PCR detected 70 (41·2%) of those pathogens. Additionally, 16S PCR detected pathogens in 13 of 299 (4·3%) culture‐negative specimens. In cohort‐2, pathogens were cultured in 52 of 430 (12·1%) specimens and 16S PCR revealed those pathogens in 32 (61·5%) specimens. 16S PCR detected pathogens in 31 of 378 (8·2%) culture‐negative specimens. Conclusions: Overall, the yield with 16S PCR was low. For cohort‐1 16S PCR detected pathogens in 4·3% of culture‐negative specimens, where this was 8·2% for cohort‐2. Significance and Impact of the Study: Although direct 16S PCR cannot replace culture, it may offer a valuable additional diagnostic option for detection of difficult to culture micro‐organisms in culture‐negative clinical specimens. [ABSTRACT FROM AUTHOR]

The prevalence of ESBL was determined among isolates of Escherichia coli (n = 571) and Klebsiella spp. (n = 196) collected during a 1-week study period in 8 university and 3 large regional laboratories all over the Netherlands. 18 isolates were positive for at least one of the screening tests used, i.e., VITEK-ESBL, E-test ESBL and MIC ratio of ceftazidime/ceftazidime-clavulanic acid, cefotaxime/cefotaxime-clavulanic acid. In 5 of these 18 putative ESBLs no betalactamase production was detectable. A TEM type was found in three E. coli and two Klebsiella spp. An SHV type was present in five Klebsiella spp. In one E. coli and one Klebsiella pneumoniae both enzymes were present. In one Klebsiella oxytoca neither of the two enzymes was present. Using PCR for both ESBL TEM and ESBL SHV, an SHV ESBL was found in one E. coli and four Klebsiella isolates. The mutations at position 238 and 240 were already described. In one E. coli isolate a TEM ESBL was found with three mutations, at position 21, 164 and 265. These mutations were already described in other ESBLs but not in this combination suggesting a new TEM ESBL. The overall prevalence of ESBL producing E. coli and Klebsiella spp. was less than 1% (6 out of 767). [ABSTRACT FROM AUTHOR]