In response to quality performance evaluations, hospitals have encouraged vaccination of eligible hospitalized adults with 23-valent pneumococcal polysaccharide vaccine (PPV23) before discharge. While examining the distribution of pneumococcal serotypes in US adults hospitalized for community-acquired pneumonia (CAP) and enrolled in the Etiology of Pneumonia in the Community (EPIC) study, we observed that in-hospital vaccination with PPV23 sometimes preceded collection of urine samples used for pneumococcal detection. We assessed the influence of in-hospital vaccination with PPV23 on detection of specific pneumococcal serotypes in urine samples.
We assessed archival urine samples from patients enrolled in the EPIC study using novel serotype-specific urinary antigen detection (SSUAD) assays. The cutoff values for SSUAD positivity vary for different serotypes.
A total of 2026 adult patients hospitalized with CAP had available urine samples tested with SSUAD; median age was 58 years. Prevalence of in-hospital vaccination with PPV23 was 11% (230/2026). We identified three patients with a sample collected one day before PPV23 vaccination and at least one sample collected after vaccination. SSUAD results for all three patients were negative before PPV23 and became positive for vaccine serotypes after PPV23 administration; two patients tested positive for serotype 5 and one for 19A (Figure). Of note, these patients tested negative for pneumococcal infection through blood cultures and BinaxNOW urinary antigen detection. We also identified four additional patients with more than one serotype detected through SSUAD who had exact times of PPV23 administration and urine sample collection documented. In these four patients, collection of urine samples occurred between 2.5-15 hours following PPV23 administration; two subjects had both serotypes 5 and 14 detected; the other two had serotypes both 5 and 19A detected.
Vaccination with PPV23 may cause false positive detections in urine samples tested through SSUAD assays, favoring detection of serotypes 5 and 19A. Caution is warranted when interpreting results from these increasingly used research assays, in the setting of recent vaccination with PPV23.
C. G. Grijalva,
Y. Zhu, None
D. J. Williams, None
R. Balk, None
S. Fakhran, None
M. Courtney, None
E. J. Anderson, Abbvie: Scientific Advisor , Speaker honorarium
C. Qi, None
C. Trabue, None
A. Pavia, None
M. R. Moore, None
S. Jain, None
K. Edwards, None
W. H. Self, Pfizer: Grant Investigator , Grant recipient