A new urinary antigen test score correlates with severity of pneumococcal pneumonia in children

ABSTRACT Little is known about the sensitivity of the BinaxNOW pneumococcal urinary antigen (PUA) test for adult pneumococcal pneumonia caused by different serotypes. In this study, we aimed to analyze the trends in the sensitivity of the PUA test over a 15-year period (2001 to 2015) and to analyze its sensitivity for pneumococcal pneumonia caused by different serotypes. In total, we analyzed 1,096 pneumococcal isolates from adults with pneumococcal pneumonia who had a PUA test performed at the onset of the episode. Three periods were analyzed: 2001 to 2005 (early use of the seven-valent pneumococcal conjugate vaccine [early PCV7]), 2006 to 2010 (late PCV7), and 2011 to 2015 (early PCV13). The sensitivity of the PUA test varied from 76.4% (95% confidence interval [CI], 70.5% to 82.4%) in the period from 2001 to 2005 to 77.9% in 2006 to 2010 (95% CI, 74.4% to 81.4%) and decreased to 60.5% (95% CI, 55.4% to 65.6%) in 2011 to 2015. This decrease was observed in 560 proven (83.2% in 2001 to 2005, 86.5% in 2006 to 2010, and 78.1%) and 536 probable (70.0% in 2001 to 2005, 68.7% in 2006 to 2010, and 41.5% in 2011 to 2015) episodes of pneumococcal pneumonia. Differences were observed in the sensitivity of the PUA test for diagnosing pneumonia caused by certain serotypes, being highest for the 9V (90.6%), 14 (86.8%), 18C (100%), and 20 (100%) serotypes and lowest for the 8 (55.2%), 9L/N (39.1%), 11A (48.8%), 23B (33.3%), and nontypeable (47.8%) serotypes. Comparing 2001 to 2005, 2006 to 2010, and 2011 to 2015, the prevalence of serotypes 9V (3.1%, 3.7%, and 1.7%, respectively) and 14 (7.2%, 5.1%, and 3.1%, respectively) decreased, while the prevalence of serotypes 23B (0%, 0.7%, and 1.4%, respectively), 9L/N (1.0%, 1.6%, and 3.4%, respectively), 11A (2.6%, 4.2%, and 3.7%, respectively), and 8 (1.5%, 1.5%, and 5.1%, respectively) increased. The PUA test sensitivity varied by pneumococcal pneumonia serotype, and these differences and the changes in serotype distribution were associated with an overall decrease in the sensitivity of the PUA test.

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Rapid diagnosis of pneumococcal pneumonia in adults using the Binax NOW Streptococcus pneumoniae urinary antigen test

International Journal of Infectious Diseases ◽

10.1016/j.ijid.2006.07.006 ◽

2007 ◽

Vol 11 (3) ◽

pp. 284-285 ◽

Cited By ~ 7

Author(s):

Bram M.W. Diederen ◽

Marcel F. Peeters

Keyword(s):

Streptococcus Pneumoniae ◽

Pneumococcal Pneumonia ◽

Rapid Diagnosis ◽

Antigen Test ◽

Urinary Antigen ◽

Urinary Antigen Test

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Detection of Streptococcus pneumoniae in Urine by Loop-Mediated Isothermal Amplification

Journal of Pediatric Infectious Diseases ◽

10.1055/s-0040-1719164 ◽

2020 ◽

Author(s):

María Dolores Cima-Cabal ◽

Emma Vázquez-Espinosa ◽

Fernando Vazquez ◽

María del Mar García-Suárez

Keyword(s):

Streptococcus Pneumoniae ◽

Predictive Value ◽

Pneumococcal Pneumonia ◽

Lamp Assay ◽

Urine Samples ◽

Healthy Children ◽

Antigen Test ◽

Urinary Antigen ◽

Urinary Antigen Test ◽

Free Dna

Abstract Objective To assess the loop-mediated isothermal amplification (LAMP) to detect cell-free DNA from Streptococcus pneumoniae in urine samples from children with pneumococcal pneumonia. Methods LAMP reactions using four primers (backward inner primer, forward inner primer, B3, and F3) targeting conserved regions of the S. pneumoniae ply gene and DNA from the recombinant plasmid pTrc99A-ply were optimized for temperature (65°C) and MgSO4 concentration (8 mM) conditions. Urine samples from 71 patients with symptoms of pneumonia and from 17 healthy children were tested side by side using the isothermal methodology LAMP and the commercial urinary antigen test, BinaxNOW S. pneumoniae assay. Percentages of sensitivity, specificity, positive predictive value (PPV), negative predictive value, and positive (LR) were calculated to compare both tests. Results The specificity of the LAMP reaction was confirmed against several species of bacteria and yeast that can cause pneumonia or urine infections. The suitability of the LAMP assay was evaluated in urine samples from 71 patients and 17 healthy children. All patients (100%) with confirmed pneumococcal pneumonia were positive for the LAMP assay. Among patients with possible/probable pneumonia, 74.1% were identified as positive using the LAMP test. Notably, a higher specificity (95.4%), PPV (94.1%) and positive LR (21.7) were found compared with the urinary antigen test. Conclusion The presence of S. pneumoniae cell-free DNA in urine samples of pediatric patients can be used as a specific diagnostic biomarker for community-acquired pneumonia by using the LAMP methodology.

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