Nosocomial pneumonia: importance of recognition of aetiological agents to define an appropriate initial empirical therapy

Of the 16 024 patients hospitalized from January 1995 to October 1997, 397 (2.4%,) acquired nosocomial pneumonia and the aetiological agent was define d in 101 (25%). About 82% developed late onset pneumonia (> 7 days of hospi talization). The site of isolation of microorganisms was bronchoalveolar la vage (BAL) (49%), blood culture (39%), pleural effusion (10%) and (2%) pulm onary tissue. Gram-negative bacteria were responsible for 54% of infections . Staphylococcus aureus (34%) was the most frequent microorganism isolated followed by Acinetobacter baumannii (29%) and Pseudomonas aeruginosa and kl ebsiella pneumoniae responsible For 7% of nosocomial pneumonia. Monotherapy gave good cover for early onset pneumonia, but not for late onset pneumoni a. Based on our selection criteria, eiprofloxacin was the best monotherapy for early (50%) and late (31%,) onset pneumonia. Vancomycin plus ciprofloxa cin gave cover of 85% of early and 64% of late onset pneumonia. Monotherapy with ciprofloxacin and also combination therapy of ciprofloxacin plus vanc omycin may be good options as initial empirical therapy for nosocomial pneu monia. (C) 2001 Published by Elsevier Science B.V. and International Societ y of Chemotherapy. All rights reserved.