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Abstract：
A hypothesis-forming exploratory cross-sectional assessment was conducted to assess the occurrence and relevance of Gram-positive rod-shaped bacteria like Corynebacterium spp. and Actinomycetaceae in human urine samples. In total, 1170 urine samples from 1031 inpatients with suspected urinary tract infection were assessed for culture-based growth of Gram-positive rod-shaped bacteria applying API Coryne assays, matrix-assisted laser desorption-ionization time-of-flight mass spectrometry (MALDI-TOF-MS), and in-house 16S rRNA gene sequencing. Overall, 502 different bacterial colonies from 346 urine samples taken from 324 inpatients were observed. The three quantitatively most abundant genera or genus clusters were Corynebacterium (254 isolates, 62%), Actinomyces/Winkia (79 isolates, 19%), and Actinotignum/Actinobaculum (29 isolates, 7%). Compared to sequencing, the diagnostic accuracy of all assessed competitor assays from the diagnostic routine was <80% for differentiation on the genus level and <30% for differentiation on the species level. Prolongated incubation for 4 days compared to 2 days resulted in additional detection of 15% of the totally recorded Gram-positive rod-shaped bacteria. An approximately 5-fold increased detection rate in mid-stream urine compared to urine acquired applying alternative sampling strategies was observed. In conclusion, in the rare event of the suspected clinical relevance of such findings, confirmatory testing with invasively sampled urine should be considered due to the high contamination rate observed in mid-stream urine. Confirmatory testing by DNA-sequencing methods should be considered if an exact identification of genus or species is regarded as relevant for the individual choice of the therapeutic strategy.
摘要：
进行了假设形成的探索性横截面评估，以评估革兰氏阳性杆状细菌如棒状杆菌属的发生和相关性。和人体尿液样本中的放线菌科。总的来说,使用APICoryne测定法评估了1031例疑似尿路感染住院患者的1170例尿液样本的革兰氏阳性杆状细菌的培养生长，基质辅助激光解吸电离飞行时间质谱(MALDI-TOF-MS),和内部16SrRNA基因测序。总的来说,从324名住院患者的346个尿液样本中观察到502个不同的细菌菌落。三个定量上最丰富的属或属簇是棒状杆菌（254个分离株，62%），放线菌/Winkia(79个分离株，19%），和放线菌/放线菌(29个分离株，7%)。与测序相比，来自诊断常规的所有评估的竞争者测定的诊断准确性对于属水平的分化为<80%,对于种水平的分化为<30%.与2天相比,延长孵育4天导致额外检测到15%的全部记录的革兰氏阳性杆状细菌。观察到与应用替代采样策略获得的尿液相比，中流尿液的检出率增加了约5倍。总之,在罕见的情况下，怀疑这些发现的临床相关性，由于在中段尿液中观察到较高的污染率，因此应考虑使用侵入性尿液采样进行验证性测试。如果属或物种的确切鉴定被认为与治疗策略的个体选择相关，则应考虑通过DNA测序方法进行的确证测试。
