Clinical usefulness of pneumococcal urinary antigen test, stratified by disease severity and serotypes

Abstract

Early diagnosis of pneumococcal pneumonia facilitates appropriate antibiotic therapy. The urinary antigen test (UAT) is known to be useful for the diagnosis of pneumococcal pneumonia. This study aimed to evaluate the usefulness of UAT in the 13-valent pneumococcal conjugated vaccine (PCV13) era. Community-acquired pneumonia (CAP) cases aged ≥19 years were reviewed retrospectively. This study evaluated the utility of Streptococcus pneumoniae UAT (BinaxNOW(®) assay) for diagnosis of pneumococcal CAP, and the relation of the UAT positive rate to age, comorbidities, pneumonia severity, and pneumococcal serotypes. Among 752 microbiologically identified CAP cases, S. pneumoniae (36.7%) was the most common isolate, and of those cases, 56.4% were positive for UAT. UAT positivity varied by pneumococcal serotype (serotype 3, 50%; 9V/9A, 85%; 11A/11E, 54%; 14, 36.4%; 19A, 50%; and 23F, 37.5%), and was significantly increased since 2012, two years after introduction of PCV13. The positive rate of UAT was significantly related to CRP level (P = 0.007) and lobar pneumonia (P = 0.006), but not to age, co-morbidities or prior antibiotic therapy. In conclusion, urinary antigen detection varied depending on the S. pneumoniae serotype. In the PCV13 era, the serotype distribution of pneumococcal pneumonia may be changing, and the clinical usefulness of UAT needs to be monitored. The positive rate of UAT may be influenced by a localized bacterial burden and host reactions.

Disease burden of hospitalized community-acquired pneumonia in South Korea

“…Although this study did not include outpatient CAP cases, 97.7% to 100% of patients with CAP were reported to receive inpatient care in South Korea because of several unique characteristics of this healthcare system (easy accessibility and high coverage level of NHI), the propensity of doctors and patients, and business-related factors. [ 19 , 21 – 23 ] Thus, the results of this study may reflect the real disease burden of CAP in South Korea; 1% to 2% of mild outpatient CAP cases might not be included, but overestimation of direct medical costs would not be remarkable.…”

Bacterial Pneumonia in Patients with Cancer

“…provides enhanced sensitivity for the diagnosis of bacterial pneumonias over culture-only strategies. Moreover, like PCR testing on respiratory secretions, urinary antigen testing can be performed in minutes, potentially improving time-to-diagnosis and time-to-correct antibiotics [112, 113]. Notably, there appears to be a strong correlation between urine antigen levels and markers of host response, including procalcitonin levels, C-reactive protein levels and lobar infiltrates on CXR.…”

Cost-effectiveness analysis of 13-valent pneumococcal conjugate vaccine versus 23-valent pneumococcal polysaccharide vaccine in an adult population in South Korea

“…Of these, the proportion of pneumococcal pneumonia incidence was assumed to be 30%, following an expert panel consultation, based on the existing research in Korea. [8][9][10][11][12][13][14][15][16][17][18] Since bacteremic pneumococcal pneumonia is classified as IPD, and thus should be excluded, the proportion of bacteremia was set to be 7%, following an expert panel consultation, based on the existing research in Korea. 8,9,12,53 Serotype coverage A S. pneumoniae serotype report, 49 which studied Korean adults in 2013-2015, was used.…”

“…The range of variation in each parameter was determined following the expert panel consultation based on existing research (Supplementary Table 3). [8][9][10][11][12][13][14][15][16][17][18]46 We also included variations in the serotypes, reflected in the estimation of the indirect effect, excluding certain serotypes (3 or 1,5 or 1,3,5); the contribution of serotype 3 to disease reduction has been reported to be low, 67 and serotypes 1 and 5 were considered uncommon colonizers. 55 Finally, we assessed differences in cost using a 0% or 5% discount rate.…”

“…6 In Korean adults, the annual incidence rates of community-acquired pneumonia (CAP) range from 538 to 707 cases per 100,000 persons, which increases with age. 7 Among CAP cases, S. pneumoniae accounts for 21.1-43.6%, [8][9][10][11][12][13][14][15][16][17][18] and 5.9% of the cases result in death. 10 The average per-capita medical fee was reported at 1,887 USD.…”