Risk Factors and Outcomes of Disseminated Nocardiosis Across Host Risk Groups

Area of Science:

• Infectious Diseases
• Clinical Microbiology
• Epidemiology

Background:

• Nocardiosis affects immunocompromised individuals and those with chronic lung disease, but can also occur in immunocompetent patients.
• Predictors of Nocardia dissemination and its impact on long-term mortality are not well understood.

Purpose of the Study:

• To identify risk factors for disseminated nocardiosis.
• To determine predictors of 1-year mortality in patients with nocardiosis.
• To analyze the association between dissemination and mortality across different patient groups.

Main Methods:

• Retrospective cohort study of adults diagnosed with nocardiosis between 2010 and 2023.
• Patients categorized into immunocompromised, immunocompetent with chronic lung disease, and immunocompetent without chronic lung disease groups.
• Multivariable logistic regression and Cox regression analyses used to identify risk factors and mortality predictors.

Main Results:

• Among 232 patients, 19% had disseminated infection and 15.5% died within 1 year.
• Dissemination was more frequent in immunocompromised patients (OR 6.26) and immunocompetent patients without chronic lung disease (OR 5.09).
• Lymphopenia and Nocardia farcinica infection were associated with dissemination. Dissemination predicted mortality only in immunocompetent patients with chronic lung disease (HR 9.43).

Conclusions:

• Immunocompromised status and absence of chronic lung disease increase disseminated nocardiosis risk.
• Dissemination is not a universal predictor of mortality but is significantly associated with mortality in immunocompetent patients with chronic lung disease.
• Tailored prognostic assessment and management are crucial for immunocompetent patients with chronic lung disease and disseminated nocardiosis.