TY - JOUR
T1 - Sputum gram stain for bacterial pathogen diagnosis in community-acquired pneumonia
T2 - A systematic review and Bayesian meta-analysis of diagnostic accuracy and yield
AU - Ogawa, Hiroaki
AU - Kitsios, Georgios D.
AU - Iwata, Mitsunaga
AU - Terasawa, Teruhiko
N1 - Funding Information:
Potential conflicts of interest. G. D. K. has received grants from the NHLBI and Karius, Inc. M. I. has received personal fees from Otsuka Pharmaceutical Co, Ltd, Astellas Pharma Inc, Eisai Co, Ltd, and Daiichi Sankyo Co, Ltd. All other authors report no potential conflicts of interest. All authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Conflicts that the editors consider relevant to the content of the manuscript have been disclosed.
Funding Information:
Financial support. This work was supported by the Ministry of Education, Culture, Sports, Science, and Technology of Japan (grant numbers 26461518 and 26460755 to T. T.) and the National Heart, Lung, and Blood Institute (NHLBI), National Institutes of Health (grant number K23 HL139981 to G. D. K.).
Publisher Copyright:
© The Author(s) 2019.
PY - 2020/8/1
Y1 - 2020/8/1
N2 - Background. The clinical role of sputum Gram stain (SGS) in community-acquired pneumonia (CAP) diagnosis remains controversial. A 1996 meta-analysis of the diagnostic accuracy of SGS reported heterogeneous results. To update the available evidence, we performed a systematic review and a Bayesian standard and latent-class model meta-analysis. Methods. We searched Medline, Embase, and Cochrane Central by 23 August 2018 to identify studies reporting on the diagnostic accuracy, yield (percentage of patients with any pathogen[s] correctly identified by SGS), and clinical outcomes of SGS in adult patients with CAP. Two reviewers extracted the data. We quantitatively synthesized the diagnostic accuracy and yield, and descriptively analyzed other outcomes. Results. Twenty-four studies with 4533 patients were included. The methodological and reporting quality of the included studies was limited. When good-quality sputum specimens were selected, SGS had a summary sensitivity of 0.69 (95% credible interval [CrI], .56-.80) and specificity of 0.91 (CrI, .83-.96) for detecting Streptococcus pneumoniae, and a sensitivity of 0.76 (CrI, .60-.87) and specificity of 0.97 (CrI, .91-.99) for Haemophilus influenzae. Adjusted analyses accounting for imperfect reference standards provided higher-specificity estimates than the unadjusted analyses. Bacterial pathogens were identified in 73% (CrI, 26%-96%) of good-quality specimens, and 36% (CrI, 22%-53%) of all specimens regardless of quality. Evidence on other bacteria was sparse. Conclusions. SGS was highly specific to diagnose S. pneumoniae and H. influenzae infections in patients with CAP. With goodquality specimens, SGS can provide clinically actionable information for pathogen-directed antibiotic therapies.
AB - Background. The clinical role of sputum Gram stain (SGS) in community-acquired pneumonia (CAP) diagnosis remains controversial. A 1996 meta-analysis of the diagnostic accuracy of SGS reported heterogeneous results. To update the available evidence, we performed a systematic review and a Bayesian standard and latent-class model meta-analysis. Methods. We searched Medline, Embase, and Cochrane Central by 23 August 2018 to identify studies reporting on the diagnostic accuracy, yield (percentage of patients with any pathogen[s] correctly identified by SGS), and clinical outcomes of SGS in adult patients with CAP. Two reviewers extracted the data. We quantitatively synthesized the diagnostic accuracy and yield, and descriptively analyzed other outcomes. Results. Twenty-four studies with 4533 patients were included. The methodological and reporting quality of the included studies was limited. When good-quality sputum specimens were selected, SGS had a summary sensitivity of 0.69 (95% credible interval [CrI], .56-.80) and specificity of 0.91 (CrI, .83-.96) for detecting Streptococcus pneumoniae, and a sensitivity of 0.76 (CrI, .60-.87) and specificity of 0.97 (CrI, .91-.99) for Haemophilus influenzae. Adjusted analyses accounting for imperfect reference standards provided higher-specificity estimates than the unadjusted analyses. Bacterial pathogens were identified in 73% (CrI, 26%-96%) of good-quality specimens, and 36% (CrI, 22%-53%) of all specimens regardless of quality. Evidence on other bacteria was sparse. Conclusions. SGS was highly specific to diagnose S. pneumoniae and H. influenzae infections in patients with CAP. With goodquality specimens, SGS can provide clinically actionable information for pathogen-directed antibiotic therapies.
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U2 - 10.1093/cid/ciz876
DO - 10.1093/cid/ciz876
M3 - Article
C2 - 31504334
AN - SCOPUS:85088847027
SN - 1058-4838
VL - 71
SP - 499
EP - 513
JO - Clinical Infectious Diseases
JF - Clinical Infectious Diseases
IS - 3
ER -