Clinic for Birds and Reptiles, University of Leipzig, Leipzig, Germany.
Institute of Molecular Pathogenesis, Friedrich-Loeffler-Institute (Federal Research Institute for Animal Health), Jena, Germany.
Microbiol Spectr. 2022 Aug 31;10(4):e0045222. doi: 10.1128/spectrum.00452-22. Epub 2022 Jul 19.
A total of 50 birds diagnosed with mycobacteriosis were examined for pathomorphological lesions, coinfections, and causative agents. Mycobacterial species were identified and isolates differentiated using multilocus sequence typing (MLST) and mycobacterial interspersed repetitive-unit variable-number of tandem-repeat (MIRU-VNTR) analysis. Possible associations between mycobacterial species, pathomorphological findings, coinfections, bird orders, and husbandry conditions were evaluated statistically. Mycobacteria were isolated from 34 birds (13 of 22 Psittaciformes, 12 of 18 Passeriformes, five of six Columbiformes, and four other orders) belonging to 26 species in total. Mycobacterium genavense (Mg) was cultured from 15 birds, Mycobacterium avium subsp. (Maa) from 20 birds, and Mycobacterium avium subsp. (Mah) from three birds; hence, four birds had mixed infections. About equal numbers of psittacines and passerines were infected with Ma and Mg. The genetic diversity differed; Mg isolates belonged to one MLST type, Maa to six, and Mah to three combined genotypes. Several coinfections were detected; viruses and/or endoparasites affected 44%, fungi 38%, and bacteria 29% of the birds. Pathological findings and mycobacteriosis-affected organs were independent of coinfections. Overall, gross pathological findings were more often seen in mycobacteriosis caused by Ma (95%) compared with Mg (66%). Organ distribution of mycobacteriosis was independent of the mycobacterial species. Pathomorphological changes were seen in the small intestine of 71% and the lung of 65% of the birds, suggesting oral or pulmonal ingestion of mycobacteria. There were no associations between mycobacterial species and bird orders or bird husbandry conditions. Not only Mg, but also Maa and Mah, were clearly identified as primary cause of mycobacteriosis in pet birds. In this study, the causative agents and confounding factors of mycobacteriosis in a set of pet and some wild birds from Germany were examined. Not only Mycobacterium genavense, but also M. avium subsp. and M. avium subsp. , contributed to mycobacteriosis in these birds. Various coinfections did not affect the manifestation of mycobacteriosis. Due to different gross necropsy findings, however, a different pathogenicity of the two species was assumed. New strains of M. avium subsp. originating from birds were identified and characterized, which is important for epidemiological studies and for understanding the zoonotic role of this pathogen, as the subsp. represents an increasing public health concern. The study provides some evidence of correlation between M. avium subsp. genotypes and virulence which will have to be confirmed by broader studies.
共有 50 只被诊断患有分枝杆菌病的鸟类接受了病理形态学病变、合并感染和病原体检查。使用多位点序列分型（MLST）和分枝杆菌插入重复单元可变数串联重复（MIRU-VNTR）分析对分枝杆菌种进行了鉴定和分离。统计评估了分枝杆菌种、病理形态学发现、合并感染、鸟类目和饲养条件之间的可能关联。从属于 26 个种的 34 只鸟（22 只鹦鹉目 13 只，18 只雀形目 12 只，6 只 Columbiformes 5 只，其他 4 目 4 只）中分离出分枝杆菌。从 15 只鸟中培养出分枝杆菌属，从 20 只鸟中培养出鸟分枝杆菌亚种，从 3 只鸟中培养出鸟分枝杆菌亚种；因此，有 4 只鸟发生了混合感染。数量相等的鹦鹉目和雀形目鸟被 Ma 和 Mg 感染。遗传多样性不同；Mg 分离株属于一种 MLST 型，Maa 有 6 种，Mah 有 3 种组合基因型。检测到几种合并感染；病毒和/或内寄生虫影响了 44%的鸟类，真菌影响了 38%的鸟类，细菌影响了 29%的鸟类。病理发现和分枝杆菌病受累器官与合并感染无关。总体而言，与 Mg（66%）相比，Ma（95%）引起的分枝杆菌病的大体病理发现更常见。分枝杆菌病的器官分布与分枝杆菌种无关。71%的鸟类小肠和 65%的鸟类肺部出现病理形态变化，提示口服或吸入分枝杆菌。分枝杆菌种与鸟类目或鸟类饲养条件之间没有关联。不仅是 Mg，还有 Maa 和 Mah，都被明确鉴定为宠物鸟分枝杆菌病的主要原因。在这项研究中，从德国的一组宠物鸟和一些野生鸟中检查了分枝杆菌病的病原体和混杂因素。不仅分枝杆菌属，而且鸟分枝杆菌亚种和鸟分枝杆菌亚种也导致了这些鸟类的分枝杆菌病。各种合并感染并未影响分枝杆菌病的表现。然而，由于大体剖检结果不同，假设两种的致病性不同。从鸟类中分离出的新型鸟分枝杆菌亚种被鉴定并具有特征，这对于流行病学研究和了解该病原体的人畜共患病作用很重要，因为亚种代表了日益严重的公共卫生问题。该研究提供了一些关于鸟分枝杆菌亚种基因型与毒力相关性的证据，这需要通过更广泛的研究来证实。
