2184. Predictors of Pneumococcal Urinary Antigen Test Positivity in Patients with Community-acquired Pneumonia: A Meta-analysis and Systematic Review
Authors: Kim Priscilla , Runsewe Oluwapeyibomi , Schleicher Mary C , Deshpande Abhishek 
Published: December 2022

Abstract

Background
The 2019 American Thoracic Society/Infectious Diseases Society of America (ATS/IDSA) guidelines argue against routine pneumococcal urinary antigen testing (pUAT), except in patients with severe community-acquired pneumonia (CAP). Recent studies, however, have suggested that these recommendations identify a low-risk population, resulting in missed opportunities for antimicrobial stewardship. The optimal patient population for pUAT thus remains unknown. Our objective was to summarize predictors of pUAT positivity among patients hospitalized with CAP as determined by previous observational studies.

Methods
We systematically searched MEDLINE, Embase, Web of Science, and Scopus for articles related to urinary antigen tests and community-acquired pneumonia. Studies published until August 26, 2021, were included if risk factors for pUAT positivity in adult patients with CAP were evaluated with multivariable analyses. No language filters or limits were applied in order to capture all potentially relevant material. Two investigators independently screened studies, extracted, and compiled data.

Results
Of the 1,144 studies that were screened, 9 met the inclusion criteria, representing 8,536 patients who underwent pUAT. The most frequent independent risk factors associated with a positive pUAT were intensive care unit (ICU) admission (OR 1.77, 95% CI 1.27 – 2.48, I2 = 21%) (Figure 1) and female sex (OR 1.53, 95% CI 1.19 – 1.97, I2 = 36%) (Figure 2). Laboratory parameters such as C-reactive protein (OR 0.26, 95% CI 0.02 – 4.49, I2 = 93%) and BUN (OR 1.36, 95% CI 0.84 – 2.19, I2 = 93%) were not significantly associated with pUAT positivity. Many variables were inconsistently reported and thus could not be combined for analysis, including age &gt; 65, current smoking, history of emphysema, hyponatremia, certain markers of severity, and antibiotic history. Figure 1:Forest plot of the association between ICU admission and positive pneumococcal UAT.
The vertical line corresponds to the no difference point between the two groups. Squares, the size of which indicates the proportion of information given by each study, correspond to ORs. Horizontal lines represent the 95% CIs. The diamond indicates the pooled odds ratios. df = degrees of freedom; IV = inverse variance Figure 2:Forest plot of the association between female sex and positive pneumococcal UAT.
The vertical line corresponds to the no difference point between the two groups. Squares, the size of which indicates the proportion of information given by each study, correspond to ORs. Horizontal lines represent the 95% CIs. The diamond indicates the pooled odds ratios. df = degrees of freedom; IV = inverse variance

Conclusion
Consistent with current guidelines, ICU admission, an indication of severe CAP, appears to be an important predictor of pUAT positivity. Additionally, however, female sex was significantly associated with pUAT positivity. Recognition of these risk factors can assist in identifying patient populations most likely to benefit from pUAT and may be considered in future CAP guidelines.

Disclosures
Abhishek Deshpande, MD, PhD, Clorox: Grant/Research Support|Merck: Advisor/Consultant|Seres Therapeutics: Grant/Research Support.