Pulmonary nontuberculous mycobacterial infection is associated with urinary molybdenum concentrations in a bronchiectasis cohort.

BACKGROUND

Epidemiologic studies have demonstrated an association between trace metals in source water and water distribution systems and nontuberculous mycobacterial (NTM) pulmonary infection and disease. Specifically, molybdenum has been strongly associated with Mycobacterium abscessus and Mycobacterium avium complex infection and disease in multiple epidemiologic studies. We aimed to determine if urinary molybdenum, chromium, and manganese concentrations were associated with pulmonary NTM infection in a bronchiectasis patient cohort.

METHODS

We enrolled 120 consecutive adult bronchiectasis patients participating in a bronchiectasis natural history study. We collected one urine sample per patient during routine visits and sent samples to the Centers for Disease Control and Prevention for trace metal testing. We defined three patient subgroups: (1) current NTM infection, (2) previous NTM infection, and (3) never NTM infection. Logistic regression models adjusted for age, racial/ethnic group, and cavitary disease status were used to test for differences between metal concentrations across infection statuses.

RESULTS

Forty-six (38%) patients were currently infected with NTM, 46 (38%) were previously infected, and 28 (23%) were never infected. For each increase of one standard deviation of the logarithm of molybdenum concentration, the odds of current versus never NTM infection increased significantly by 14% [odds ratio (OR) = 1.14, 95% confidence interval (CI) = 1.02, 1.28], while manganese and chromium did not exhibit significant associations.

CONCLUSIONS

This clinical study is the first to examine the relationship between trace metals and pulmonary NTM infections. These findings support those from prior population-based studies.