Diagnostic and therapeutic advantages of serial quantitative cultures of fresh sputum in acute bacterial pneumonia.

Abstract

Quantitative cultures were made of fresh homogenized sputum on admission and at repeated intervals during the illness of 20 consecutively admitted patients hospitalized for acute bacterial pneumonia without prior antimicrobial treatment. This technique led to more frequent isolation of pathogens than did routine methods. Although more careful collection and rapid processing of the sputum samples contributed to the superior results, liquefaction and thorough mixing appeared to be the most important factors. Quantitation was helpful in recognizing mixed infections, in determining whether superinfection was present, in following the effects of antimicrobial drugs, and in permitting a study of the interrelationship of organisms to one another. Enumeration of the number of bacteria in sputum provided much greater information and insight into the etiologic agent, pathogenesis, and therapy of acute bacterial pneumonia than is available with the usual methods. This technique is within the means of most laboratori...