Barada Ghyda, Basma Raida, Khalaf Roy A
Natural Sciences Division, Lebanese American University, P.O. Box 36, Byblos, Lebanon.
Mycopathologia. 2008 Mar;165(3):115-25. doi: 10.1007/s11046-008-9089-0. Epub 2008 Feb 12.
The present study involves collecting 125 isolates labeled as C. albicans from five different Lebanese hospitals and utilizing the microsatellite genotyping test to determine the following: first, the accuracy of hospital identification by comparing microsatellite results to hospital results. Second, the frequency and genotypes of infectious strains present relative to tissue and hospital location--a possible indicator of nosocomial infection, and third, a possible relationship between lack of microsatellite heterozygosity to azole resistance. Our results showed that the error in hospital identification varied from 2 to 33%, averaging at 7%, with the highest identification error in stool. Misidentified isolates were mainly Candida tropicalis followed by C. glabrata and C. parapsilosis. Strains with similar genotypes were also found to occur within certain hospitals suggesting the possibility of nosocomial infection. Finally, a relationship between lack of heterozygosity and azole resistance was observed since nine out of 10 homozygous isolates sharing a common allele with a heterozygote strain were sensitive to all drugs tested, whereas the homozygous genotype was resistant to at least one drug.
本研究包括从黎巴嫩五家不同医院收集125株标记为白色念珠菌的分离株,并利用微卫星基因分型试验来确定以下内容:第一,通过将微卫星结果与医院结果进行比较,确定医院鉴定的准确性。第二,相对于组织和医院位置,存在的感染菌株的频率和基因型——这可能是医院感染的一个指标,第三,微卫星杂合性缺乏与唑类耐药性之间可能存在的关系。我们的结果表明,医院鉴定中的错误率在2%至33%之间,平均为7%,粪便中的鉴定错误率最高。错误鉴定的分离株主要是热带念珠菌,其次是光滑念珠菌和近平滑念珠菌。在某些医院中也发现了具有相似基因型的菌株,这表明存在医院感染的可能性。最后,观察到杂合性缺乏与唑类耐药性之间的关系,因为与杂合子菌株共享一个共同等位基因的10株纯合分离株中有9株对所有测试药物敏感,而纯合基因型对至少一种药物耐药。