捐精志愿者精液细菌学分析

Bacteriological analysis of semen samples from sperm donors

目的:探讨捐精志愿者精液细菌分布情况及特点。方法:由于目前无男性精液细菌培养和菌落计数的参考值,依据男性尿路感染诊断标准(尿液细菌培养菌落数>10^(5)cfu/ml应认为有感染,<10^(4)cfu/ml可能为污染,10^(4)cfu/ml~10^(5)cfu/ml之间为可疑),重庆市人类精子库将菌落数≥10^(4)cfu/ml作为精液细菌培养不合格的界限。对2015年4月至2019年11月到重庆市人类精子库自愿捐精的3160例捐精志愿者的精液样本进行细菌培养,采用英国synbiosis全自动菌落计数仪进行菌落计数,法国梅里埃VITEK2 Compact全自动微生物鉴定仪对菌落数≥10^(4)cfu/ml的样本进行菌种鉴定。结果:捐精志愿者精液样本无细菌生长456例,占14.43%,有细菌生长2704例,细菌携带率为85.57%,其中杂菌污染143例,占4.53%,未被杂菌污染的精液样本中细菌培养阳性2561例,占81.04%,包括菌落数<10^(4)cfu/ml精液样本2305例,占72.94%,菌落数≥10^(4)cfu/ml的精液样本256例,占8.10%。细菌鉴定结果中革兰氏阳性菌(G^(+))占87.89%(225/256),革兰氏阴性菌(G^(-))占12.11%(31/256),其中以表皮葡萄球菌(Staphylococcus epidermidis)、溶血性葡萄球菌(Hemolytic staphylococcus)、极小棒状杆菌(Corynebacterium)、粪肠球菌(Enterococcus faecalis)、金黄色葡萄球菌(Staphylococcus aureus)为主,分别占26.95%、16.40%、13.28%、6.64%、5.86%。结论:捐精志愿者精液样本细菌携带率高,种类多,以G^(+)菌为主。

Objective:To explore the distribution and characteristics of semen bacteria in sperm donors.Methods:For lack of the reference value for semen bacterial culture and colony count,we referred to the existing criteria for the diagnosis of male urinary tract infection(urine bacterial colonies>10^(5)cfu/ml for infection,<10^(4)cfu/ml for possible bacterial contamination,and 10^(4)-10^(5)cfu/ml for suspected infection)and set the threshold value for unqualified semen culture at bacterial colonies≥10^(4)cfu/ml.We performed bacterial culture of the semen samples from 3160 sperm donors in the Chongqing Human Sperm Bank from April 2015 to November 2019,counted the bacterial colonies using the British Synbiosis automatic colony counter,and identified the bacterial species in the samples with bacterial colonies≥10^(4)cfu/ml with the automatic microbial identification instrument.Results:Of the 3160 semen samples,456(14.43%)were found without bacterial growth,and the other 2704(85.57%)with bacterial growth,which included 143(4.53%)with miscellaneous bacteria contamination and 2561(81.04%)positive for bacterial culture but not contaminated,the latter including 2305(72.94%)with bacterial colonies<10^(4)cfu/ml and 256(8.10%)with bacterial colonies≥10^(4)cfu/ml.Bacterial identification showed that 87.89%of the bacteria were Gram-positive(G^(+))and 12.11%Gram-negative(G^(-)),mainly including Staphylococcus epidermidis(26.95%),Hemolytic staphylococcus(16.40%),Corynebacterium(13.28%),Enterococcus faecalis(6.64%)and Staphylococcus aureus(5.86%).Conclusion:Semen samples from sperm donors have a high rate of bacteria-carriers,and the bacteria vary widely in strain,with G^(+)bacteria as the main type.