Dube Felix S, Kaba Mamadou, Robberts F J Lourens, Ah Tow Lemese, Lubbe Sugnet, Zar Heather J, Nicol Mark P
Division of Medical Microbiology, Department of Pathology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa.
Faculty of Health Sciences, Institute for Infectious Diseases and Molecular Medicine, University of Cape Town, Cape Town, South Africa.
BMC Infect Dis. 2016 Oct 24;16(1):597. doi: 10.1186/s12879-016-1934-z.
Lower respiratory tract infection in children is increasingly thought to be polymicrobial in origin. Children with symptoms suggestive of pulmonary tuberculosis (PTB) may have tuberculosis, other respiratory tract infections or co-infection with Mycobacterium tuberculosis and other pathogens. We aimed to identify the presence of potential respiratory pathogens in nasopharyngeal (NP) samples from children with suspected PTB.
NP samples collected from consecutive children presenting with suspected PTB at Red Cross Children's Hospital (Cape Town, South Africa) were tested by multiplex real-time RT-PCR. Mycobacterial liquid culture and Xpert MTB/RIF was performed on 2 induced sputa obtained from each participant. Children were categorised as definite-TB (culture or qPCR [Xpert MTB/RIF] confirmed), unlikely-TB (improvement of symptoms without TB treatment on follow-up) and unconfirmed-TB (all other children).
Amongst 214 children with a median age of 36 months (interquartile range, [IQR] 19-66 months), 34 (16 %) had definite-TB, 86 (40 %) had unconfirmed-TB and 94 (44 %) were classified as unlikely-TB. Moraxella catarrhalis (64 %), Streptococcus pneumoniae (42 %), Haemophilus influenzae spp (29 %) and Staphylococcus aureus (22 %) were the most common bacteria detected in NP samples. Other bacteria detected included Mycoplasma pneumoniae (9 %), Bordetella pertussis (7 %) and Chlamydophila pneumoniae (4 %). The most common viruses detected included metapneumovirus (19 %), rhinovirus (15 %), influenza virus C (9 %), adenovirus (7 %), cytomegalovirus (7 %) and coronavirus O43 (5.6 %). Both bacteria and viruses were detected in 73, 55 and 56 % of the definite, unconfirmed and unlikely-TB groups, respectively. There were no significant differences in the distribution of respiratory microbes between children with and without TB. Using quadratic discriminant analysis, human metapneumovirus, C. pneumoniae, coronavirus 043, influenza virus C virus, rhinovirus and cytomegalovirus best discriminated children with definite-TB from the other groups of children.
A broad range of potential respiratory pathogens was detected in children with suspected TB. There was no clear association between TB categorisation and detection of a specific pathogen. Further work is needed to explore potential pathogen interactions and their role in the pathogenesis of PTB.
越来越多的人认为儿童下呼吸道感染起源于多种微生物。有疑似肺结核（PTB）症状的儿童可能患有结核病、其他呼吸道感染或结核分枝杆菌与其他病原体的合并感染。我们旨在确定疑似PTB儿童鼻咽（NP）样本中潜在呼吸道病原体的存在情况。
对在南非开普敦红十字会儿童医院连续就诊的疑似PTB儿童采集的NP样本进行多重实时逆转录聚合酶链反应检测。对每个参与者采集的2份诱导痰进行分枝杆菌液体培养和Xpert MTB/RIF检测。儿童被分为确诊结核病（培养或定量聚合酶链反应[Xpert MTB/RIF]确诊）、非结核病（随访中未经结核病治疗症状改善）和未确诊结核病（所有其他儿童）。
在214名中位年龄为36个月（四分位间距，[IQR]19 - 66个月）的儿童中，34名（16%）患有确诊结核病，86名（40%）患有未确诊结核病，94名（44%）被归类为非结核病。在NP样本中检测到的最常见细菌为卡他莫拉菌（64%）、肺炎链球菌（42%）、流感嗜血杆菌属（29%）和金黄色葡萄球菌（22%）。检测到的其他细菌包括肺炎支原体（9%）、百日咳博德特菌（7%）和肺炎衣原体（4%）。检测到的最常见病毒包括偏肺病毒（19%）、鼻病毒（15%）、C型流感病毒（9%）、腺病毒（7%）、巨细胞病毒（7%）和O43冠状病毒（5.6%）。在确诊、未确诊和非结核病组中，分别有73%、55%和56%的儿童同时检测到细菌和病毒。患结核病和未患结核病的儿童之间呼吸道微生物的分布没有显著差异。使用二次判别分析，人偏肺病毒、肺炎衣原体、O43冠状病毒、C型流感病毒、鼻病毒和巨细胞病毒最能将确诊结核病儿童与其他儿童组区分开来。
在疑似结核病儿童中检测到多种潜在呼吸道病原体。结核病分类与特定病原体的检测之间没有明确关联。需要进一步开展工作来探索潜在病原体的相互作用及其在PTB发病机制中的作用。
