Department of Clinical Microbiology, Karolinska University Hospital, Stockholm, Sweden.
Department of Medicine, Division of Infectious Diseases, Karolinska Institutet, Solna, Sweden.
J Infect Dis. 2023 Mar 28;227(6):820-827. doi: 10.1093/infdis/jiad007.
The Mycobacterium abscessus complex (MABC) is a difficult to treat mycobacterium with two distinct morphologies: smooth and rough. As the clinical implications are unclear, we explored the morphology of MABC in relation to disease and outcome.
We performed a retrospective multicenter cohort study including patients with confirmed MABC in Sweden, 2009-2020, with treatment outcome as the primary outcome. MABC colony morphology was determined by light microscopy on Middlebrook 7H10 agar plates.
Of the 71 MABC isolates, a defined morphology could be determined for 63 isolates, of which 40 were smooth (56%) and 23 were rough (32%). Immunosuppression, pulmonary disease, and cavitary lesion on chest radiographs were significantly associated with a rough isolate morphology. Participants with smooth isolates had more favorable treatment outcomes (12/14, 86%) compared to those with rough isolates (3/10, 30%). In an age-adjusted logistic regression, rough morphology of MABC was associated to lower odds of clinical cure compared to smooth morphology (adjusted odds ratio, 0.12; P = .049).
Study participants with rough MABC colony morphology of isolates had a worse clinical outcome compared to those with smooth isolates. The biological mechanisms should be further characterized and colony morphology of MABC taken into account during clinical management.
脓肿分枝杆菌复合体（MABC）是一种难以治疗的分枝杆菌，具有两种不同的形态：光滑型和粗糙型。由于其临床意义尚不清楚，我们探讨了 MABC 的形态与疾病和结局的关系。
我们进行了一项回顾性多中心队列研究，纳入了 2009 年至 2020 年在瑞典确诊的 MABC 患者，以治疗结局为主要结局。通过在 Middlebrook 7H10 琼脂平板上进行光学显微镜检查来确定 MABC 菌落形态。
在 71 株 MABC 分离株中，可确定 63 株的明确形态，其中 40 株为光滑型（56%），23 株为粗糙型（32%）。免疫抑制、肺部疾病和胸部 X 线片上的空洞病变与粗糙分离株形态显著相关。光滑分离株组的治疗结局更有利（12/14，86%），而粗糙分离株组的治疗结局较差（3/10，30%）。在年龄调整的逻辑回归中，与光滑形态相比，MABC 的粗糙形态与临床治愈的可能性较低相关（调整后的优势比，0.12；P=0.049）。
与光滑分离株相比，MABC 分离株的粗糙菌落形态的研究参与者的临床结局较差。应进一步研究其生物学机制，并在临床管理中考虑 MABC 的菌落形态。
