Mortality After Nocardiosis: Risk Factors and Evaluation of Disseminated Infection

• Published in: Open forum infectious diseases Vol. 10; no. 8; p. ofad409
• Main Authors: Yetmar, Zachary A, Khodadadi, Ryan B, Chesdachai, Supavit, McHugh, Jack W, Challener, Douglas W, Wengenack, Nancy L, Bosch, Wendelyn, Seville, Maria Teresa, Beam, Elena
• Format: Journal Article
• Language: English
• Published: US Oxford University Press 01.08.2023
• Subjects: Actinomycetales infections; Comorbidity; Diseases; Health aspects; Imipenem; Infants (Newborn); Lung diseases; Major; Medical research; Medicine, Experimental; Minnesota; Mortality; Prognosis; Risk factors; Minnesota; mortality; advanced infection; nocardia; nocardiosis; disseminated infection
• ISSN: 2328-8957; 2328-8957
• DOI: 10.1093/ofid/ofad409

Abstract Background Nocardia primarily infects patients who are immunocompromised or those with chronic lung disease. Although disseminated infection is widely recognized as an important prognostic factor, studies have been mixed on its impact on outcomes of nocardiosis. Methods We performed a retrospective cohort study of adults with culture-confirmed nocardiosis. Advanced infection was defined as disseminated infection, cavitary pulmonary infection, or pleural infection. The primary outcome was 1-year mortality, as analyzed by multivariable Cox regression. Results Of 511 patients with culture growth of Nocardia, 374 (73.2%) who had clinical infection were included. The most common infection sites were pulmonary (82.6%), skin (17.9%), and central nervous system (14.2%). In total, 117 (31.3%) patients had advanced infection, including 74 (19.8%) with disseminated infection, 50 (13.4%) with cavitary infection, and 18 (4.8%) with pleural infection. Fifty-nine (15.8%) patients died within 1 year. In multivariable models, disseminated infection was not associated with mortality (hazard ratio, 1.16; 95% CI, .62–2.16; P = .650) while advanced infection was (hazard ratio, 2.48; 95% CI, 1.37–4.49; P = .003). N. farcinica, higher Charlson Comorbidity Index, and culture-confirmed pleural infection were also associated with mortality. Immunocompromised status and combination therapy were not associated with mortality. Conclusions Advanced infection, rather than dissemination alone, predicted worse 1-year mortality after nocardiosis. N. farcinica was associated with mortality, even after adjusting for extent of infection. While patients who were immunocompromised had high rates of disseminated and advanced infection, immunocompromised status did not predict mortality after adjustment. Future studies should account for high-risk characteristics and specific infection sites rather than dissemination alone. Disseminated infection and immunocompromised status were not associated with 1-year mortality after nocardiosis, while advanced infection (dissemination, pulmonary cavitation, and/or pleural involvement) and Nocardia farcinica were significant associations. Microbiologic characteristics and infection phenotype should be considered in patients with nocardiosis.