Rahdar Hossein Ali, Salehi Mohammad Reza, Bahador Abass, Jasemi Seyedesomaye, Karami-Zarandi Morteza, Nejad Malehe Hasan, Shahraki-Zahedani Shahram, Amani Jafar, Feyisa Seifu Gizaw, Kardan-Yamchi Jalil, Feizabadi Mohammad Mehdi
Department of Medical Microbiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
Department of Microbiology, School of Medicine, Iranshahr University of Medical Sciences, Iranshahr, Iran.
Ethiop J Health Sci. 2019 Nov;29(6):737-744. doi: 10.4314/ejhs.v29i6.10.
Nocardia, Streptomyces and Rhodococcus are life threatening opportunistic pathogens under immunodeficiency conditions, particularly among patients infected with HIV. Rapid and accurate detection of these infections can improve immune health quality, patient management and appropriate treatment. The aim of this study was to design a novel multiplex-PCR assay for rapid diagnosis of these three organisms directly from bronchoalveolar lavage (BAL) specimens of patients infected with HIV.
The genus specific primers were designed for direct-detection of Nocardia, Streptomyces and Rhodococcus in a single tube multiplex PCR. This PCR specifically amplified the target genes from pure cultures. It subsequently was applied on BAL specimens of 29 HIV positive patients that had previously been culture negative for actinomycete bacteria, of which Nocardia, Streptomyces and Rhodococcus are members.
Of 29 respiratory clinical specimens, there were positive for Nocardia spp. and one was positive for Streptomyces spp using the multiplex PCR assay. The sequencing of the PCR products identified the species as Nocardia cyriacigeorgica (n=2), Nocardia farcinica and Streptomyces albus.
This novel multiplex PCR assay yielded reliable results for accurate identification of Nocardia, Streptomyces and Rhodococcus from BAL while the results of bacterial culture were negative.
诺卡菌属、链霉菌属和红球菌属是免疫缺陷条件下的危及生命的机会致病菌,尤其是在感染HIV的患者中。快速准确地检测这些感染可改善免疫健康质量、患者管理和适当治疗。本研究的目的是设计一种新型多重PCR检测方法,用于直接从HIV感染患者的支气管肺泡灌洗(BAL)标本中快速诊断这三种微生物。
设计属特异性引物,用于在单管多重PCR中直接检测诺卡菌属、链霉菌属和红球菌属。该PCR从纯培养物中特异性扩增靶基因。随后将其应用于29例HIV阳性患者的BAL标本,这些患者先前放线菌培养阴性,其中包括诺卡菌属、链霉菌属和红球菌属。
在29份呼吸道临床标本中,使用多重PCR检测法检测到诺卡菌属阳性2份,链霉菌属阳性1份。PCR产物测序鉴定出这些菌种为乔治亚嗜麦芽窄食单胞菌(n = 2)、恶臭诺卡菌和白色链霉菌。
这种新型多重PCR检测法在细菌培养结果为阴性时,能从BAL中可靠地准确鉴定诺卡菌属、链霉菌属和红球菌属。