Mycobacterium xenopi is associated with the highest mortality among pulmonary nontuberculous mycobacterial (NTM) infections, but whether this is due to the infection or other factors is unclear. There is little information regarding outcomes among patients infected with M. xenopi versus other NTM species.

We conducted a retrospective matched cohort study comparing M. xenopi pulmonary disease (Mx-PD) to M. avium complex (MAC)-PD. Patients were matched by sex, age, radiologic subtype, and presence of cavitation. Baseline clinical characteristics, treatment, and outcomes were compared using matched analyses.

We identified 70 Mx-PD cases: 29 fibrocavitary-type, 28 nodular-bronchiectatic-type, and 13 unclassifiable-type CT patterns, mean (SD) age 63 (13) years, and 54.3% (n = 38) female. Median follow-up duration was longer in the Mx-PD cohort (1552 days versus 1035 days, p = 0.01). Symptoms, radiologic phenotype, and pulmonary function were similar between groups although the Charlson Comorbidity Index was numerically higher in Mx-PD patients (3.6 versus 3.2, p = 0.08). Rifamycins were used less frequently in Mx-PD (59.5% versus 85.7%, p = 0.02). Although combined clinical and radiologic improvement was similar between the groups, successful treatment was more common with Mx-PD (40.5% versus 16.7%, p = 0.02) owing to superior culture conversion (70.8% versus 33.3%, p = 0.0001). Mortality 24 months after initiation of treatment was numerically but not statistically greater in the Mx-PD cohort (20.4% versus 10.3%, p = 0.32).

Among matched Mx-PD and MAC-PD patients, standard anti-mycobacterial treatment was significantly more likely to achieve culture conversion and successful treatment for Mx-PD patients. Mortality among Mx-PD patients was numerically, but not statistically higher, possibly explained by increased comorbidity burden.

在肺非结核分枝杆菌（NTM）感染中，异种分枝杆菌与最高死亡率相关，但是尚不清楚这是由于感染还是其他因素引起的。关于异种分枝杆菌与其他NTM物种感染的患者之间的结局信息很少。

我们进行了一项回顾性配对队列研究，比较了异种支原体肺部疾病（Mx-PD）与鸟支原体复合体（MAC）-PD。根据性别，年龄，放射学亚型和空化情况对患者进行匹配。使用匹配分析比较基线临床特征，治疗和结果。

我们确定了70例Mx-PD病例：29例为纤维肉眼型，28例为结节性支气管扩张型和13例无法分类的CT模式，平均（SD）年龄为63（13）岁，女性为54.3％（n = 38）。在Mx-PD队列中，中位随访时间较长（1552天对1035天，p = 0.01）。两组之间的症状，放射学表型和肺功能相似，尽管Mx-PD患者的Charlson合并症指数在数值上更高（3.6比3.2，p = 0.08）。利福霉素在Mx-PD中的使用频率较低（59.5％对85.7％，p = 0.02）。尽管两组之间的临床和放射学综合改善相似，但由于较高的培养转化率，Mx-PD的成功治疗更为常见（40.5％对16.7％，p = 0.02）（70.8％对33.3％，p = 0.0001）。

在匹配的Mx-PD和MAC-PD患者中，标准抗分枝杆菌治疗显着更有可能实现培养转换并成功治疗Mx-PD患者。Mx-PD患者的死亡率在数字上有所提高，但在统计学上并未更高，这可能是由于合并症负担增加所致。