Short- and long-term prognosis of patients with community-acquired legionella or pneumococcal pneumonia diagnosed by urinary antigen testing.

OBJECTIVE: To analyse differences in short- and long-term prognosis and predictors of survival between patients with community-acquired Legionella and S. pneumoniae pneumonia, diagnosed early by urinary antigen testing (UAT).

METHODS: Prospective multicentre study conducted in inmunocompetent patients hospitalised with community-acquired Legionella or pneumococcal pneumonia (L-CAP or P-CAP) between 2002-2020. All cases were diagnosed based on positive UAT.

RESULTS: We included 1452 patients, 260 with L-CAP and 1192 with P-CAP. Thirty-day mortality was higher for L-CAP (6.2%) than for P-CAP (5%). After discharge and during median follow-ups of 11.4 and 8.43 years, 32.4% and 47.9% of L-CAP and P-CAP patients died, and 82.3% and 97.4% died earlier than expected respectively. Independent risk factors for shorter long-term survival were: age >65 years, chronic obstructive pulmonary disease, cardiac arrhythmia and congestive heart failure in L-CAP; and the same first three factors plus nursing home residence, cancer, diabetes mellitus, cerebrovascular disease, altered mental status, blood urea nitrogen ≥30 mg/dL and congestive heart failure as a cardiac complication during hospitalization in P-CAP.

CONCLUSIONS: In patients diagnosed early by UAT, long-term survival after L-CAP or P-CAP was shorter (particularly after P-CAP) than expected, and this shorter survival was mainly associated with age and comorbidities.