Nosocomial Respiratory Infections with Gram-Negative Bacilli

Abstract

A prospective study of 213 patients admitted to a medical intensive care unit was done to determine the frequency of colonization of the respiratory tract with Gram-negative bacilli and the relation of such colonization to nosocomial infection. Ninety-five patients (45%) became colonized, 22% on the first hospital day. Associated with colonization were respiratory tract disease, coma, hypotension, tracheal intubation, acidosis, azotemia, and either leukocytosis or leukopenia. Antimicrobial therapy may have promoted colonization in some patients. Nosocomial infections developed in 26 patients (12.2%), 22 of whom were colonized with Gram-negative bacilli. Nosocomial respiratory infections occurred in 23% of colonized patients but in only 3.3% of noncolonized patients. The control of nosocomial pneumonia may require the development of methods for preventing or interrupting the colonization of hospitalized patients with Gram-negative bacilli.