The Bottom Line: This study found the sensitivity of sputum Gram stain was 0.82 for Pneumococcal pneumonia, 0.76 for Staphylococcal pneumonia, 0.79 for Haemophilus influenzae pneumonia and 0.78 for Gram-negative bacilli pneumonia. Specificity of sputum Gram stain was 0.93 for Pneumococcal pneumonia, 0.96 for Staphylococcal pneumonia, 0.96 for H. influenzae pneumonia and 0.95 for Gram-negative bacilli pneumonia.
Anevlavis, Stavros A prospective study of the diagnostic utility of sputum Gram stain in pneumonia. The Journal of infection 2009 vol:59 iss:2 pg:83 -89
Pneumonia remains a major cause of death worldwide and the sixth most common cause of death in United States of America. The 1-year mortality may be as high as 40% in Medicare patients who have been admitted to the hospital with community acquired pneumonia. The study concluded sputum gram stain is a dependable diagnostic test for the early etiological diagnosis of bacterial CAP that helps in choosing orthological and appropriate initial antimicrobial therapy.