Iwasaki Kotaro, Matsuzawa Yasuo, Wakabayashi Hiroki, Shioya Moe, Hayakawa Sho, Tatsuno Ichiro
Department of Internal Medicine, Toho University Sakura Medical Center, Japan.
Department of Diabetes, Endocrinology and Metabolism, Toho University Graduate School of Medicine, Japan.
Heliyon. 2021 Jun 11;7(6):e07283. doi: 10.1016/j.heliyon.2021.e07283. eCollection 2021 Jun.
The relationship between the lower airway microbiota in humans and respiratory illness has gained attention recently. However, the relationship between nontuberculous mycobacterial lung disease (NTM-LD) and the lower airway microbiota is not fully understood yet. We conducted a study to characterize the lower airway microbiota in complex lung disease (MAC-LD), a representative subclass of the NTM-LD. The subject sample included 25 patients clinically suspected of having mild MAC disease whose condition could not be diagnosed using sputum culture. Upon testing MAC antibodies (anti-glycopeptidolipid (GPL)-core IgA antibodies), mycobacterial culture of bronchoalveolar lavage fluid (BALF), and performing BALF 16S rRNA gene sequencing, we divided the subjects into two groups of patients: those in whom MAC was detected in BALF mycobacterial culture (MAC-LD group) and in whom MAC was not detected in BALF mycobacterial culture (non-MAC-LD group), which was then comparatively examined. BALF mycobacterial culture showed that 9 out of 25 patients were positive for NTM; the detected was MAC in all. No patients were positive for acid-fast bacteria other than MAC. Eighteen patients were positive for MAC antibodies (anti-glycopeptidolipid (GPL)-core IgA antibodies), including nine patients positive for mycobacterial culture. On BALF 16S rRNA gene sequencing, six patients were positive for the genus and were culture-positive. Among the 16 patients in the non-MAC-LD group, the genus was detected by 16S rRNA gene sequencing in 7 patients, 4 among whom were positive for MAC antibodies (anti-GPL-core IgA antibodies). Conversely, the genus was not detected among the nine patients in the MAC-LD group. Other than the genus , there was no clear difference in the composition of and no significant difference in the diversity of the bacterial flora between the MAC-LD and non-MAC-LD groups. However, we found that the genus and MAC tended to exist exclusively.
人类下呼吸道微生物群与呼吸道疾病之间的关系最近受到了关注。然而，非结核分枝杆菌肺病（NTM-LD）与下呼吸道微生物群之间的关系尚未完全明确。我们开展了一项研究，以对NTM-LD的一个代表性子类——复杂性肺病（MAC-LD）中的下呼吸道微生物群进行特征分析。受试者样本包括25例临床疑似患有轻度MAC病但无法通过痰培养确诊病情的患者。在检测MAC抗体（抗糖脂肽（GPL）核心IgA抗体）、支气管肺泡灌洗液（BALF）的分枝杆菌培养以及进行BALF 16S rRNA基因测序后，我们将受试者分为两组患者：在BALF分枝杆菌培养中检测到MAC的患者（MAC-LD组）和在BALF分枝杆菌培养中未检测到MAC的患者（非MAC-LD组），然后对其进行比较研究。BALF分枝杆菌培养显示，25例患者中有9例NTM呈阳性；检测到的均为MAC。除MAC外，没有患者抗酸杆菌呈阳性。18例患者MAC抗体（抗糖脂肽（GPL）核心IgA抗体）呈阳性，其中9例分枝杆菌培养呈阳性。在BALF 16S rRNA基因测序中，6例患者的该属呈阳性且培养呈阳性。在非MAC-LD组的16例患者中，7例通过16S rRNA基因测序检测到该属，其中4例MAC抗体（抗GPL核心IgA抗体）呈阳性。相反，MAC-LD组的9例患者中未检测到该属。除该属外，MAC-LD组和非MAC-LD组之间的细菌菌群组成没有明显差异，细菌菌群多样性也没有显著差异。然而，我们发现该属和MAC往往单独存在。
