Bacteriologic studies of the sputum in patients with pneumococcal pneumonia treated with penicillin.

Abstract

Abstract Sputum and throat cultures and stained smears of sputum were studied before, during, and after treatment with penicillin in twenty-six patients with pneumococcal pneumonia. Considerable differences were noted in the persistence of pneumococci in these patients. About one-sixth of the strains found before penicillin therapy was started persisted throughout the period of observation. About three-fourths of the remaining strains could no longer be found after the third day of treatment. Strains of pneumococci of types not identified in the pretreatment cultures were found for the first time during or after penicillin therapy in six patients. Only one of the strains, however, was found in more than a single specimen. All of the strains of pneumococci tested were sensitive to penicillin, and three strains isolated after therapy were found to be just as sensitive as the pretreatment strains of the same types isolated from the same patients. The persistence of pneumococci in the sputum did not appear to be definitely related to bacteremia, complications, chronic respiratory infections, the numbers of organisms present before treatment, the development of penicillin resistance, or the failure to develop antibodies, as judged by phagocytosis of pneumococci in stained smears. In one patient a staphylococcal pneumonia developed as a complication of the pneumococcal lobar pneumonia. The staphylococcus first appeared in the culture of the sputum obtained twelve hours after penicillin was started and then became predominant in subsequent cultures. It was quite resistant to penicillin, and improvement occurred only after intensive sulfonamide therapy. Following penicillin therapy, the flora of the sputum changed in most instances to one in which the predominant organisms were gram-negative bacilli having the morphology and colony characteristics of influenza bacilli.