Impact of prior pulmonary tuberculosis in treatment outcomes of HCAP and CAP patients in intensive care units

Background/purpose: It is controversial whether healthcare-associated pneumonia (HCAP) belongs to a unique clinical entity or it shares common characteristics with community-acquired pneumonia (CAP). The impact of prior pulmonary tuberculosis (PTB) in clinical presentation and treatment outcome of ICU-admitted CAP and HCAP patients also remains unknown. Methods: We report a nationwide, multi-center, retrospective study. ICU-admitted CAP and HCAP patients from six medical centers in Taiwan were enrolled for analysis. Patients were defined as either CAP or HCAP cases, and with and without prior PTB, according to the database of Taiwan CDC. The disease severity, microbiologic characteristics, and treatment outcomes between CAP and HCAP patients with or without prior PTB were compared and analyzed. Results: A total of 414 ICU-admitted patients, including 176 CAP cases and 238 HCAP cases were included for analysis during the study period. In both CAP and HCAP subgroups, the pneumonia severities, proportions of organ dysfunction, and microbiologic characteristics were similar between patients with and without prior PTB. In survival analysis, patients with prior PTB had higher 30-day mortality than those without prior PTB (38.9% vs. 16.5%, p = 0.021) in the CAP population. Multivariate analysis revealed that a history of prior PTB was an independent clinical factor associated with higher 30-day mortality rate in CAP patients (HR = 4.45, 95% CI: 1.81–10.98, P = 0.001). Conclusion: History of prior PTB is an independent clinical factor for increased 30-day mortality rate in ICU-admitted CAP patients, but not in ICU-admitted HCAP patients. Keywords: Community-acquired pneumonia, Healthcare-associated pneumonia, Intensive care unit, Mortality, Tuberculosis