Rapid urinary antigen test for diagnosis of pneumococcal community-acquired pneumonia in adults

Abstract

Streptococcus pneumoniae is suspected to cause an important proportion of community-acquired pneumonia (CAP) whose aetiology cannot be detected with conventional tests.In this study, the authors evaluated the diagnostic yield of a new immunochromatographic membrane test (ICT) for the detection of the S. pneumoniae antigen in the urine of patients admitted with diagnosed CAP. ICT was performed in unconcentrated and concentrated urine from all the patients. ICT was repeated 1 month after discharge in a group initially testing positive. The authors also studied the ICT in clinically stable human immunodeficiency virus type 1 (HIV1)-infected patients.S. pneumoniae antigen was detected in all of the 68 (100%) patients tested with definitive pneumococcal pneumonia. In five of these cases ICT was only positive when it had been performed on the patients. The S. pneumoniae antigen was also detected in 36 (69.2%) of 52 patients with probable pneumococcal pneumonia and in 50 of 277 (18%) patients without pneumococcal pneumonia. ICT remained positive in 16 (69.5%) of 23 patients, 1 month after hospital discharge. Nasopharyngeal colonisation with S. pneumoniae was detected in 8 (12%) of 68 clinically stable HIV1 infected patients, but none tested ICT positive.The Binax NOW1 immunochromatographic membrane test is a rapid, sensitive and specific test for detecting pneumococcal community-acquired pneumonia in adults. The test may remain positive for several weeks after pneumococcal pneumonia.

Randomised controlled trial and health economic evaluation of the impact of diagnostic testing for influenza, respiratory syncytial virus and Streptococcus pneumoniae infection on the management of acute admissions in the elderly and high-risk 18- to 64-year-olds

“…Although blood culture is used as the 'gold standard' for diagnosis of pneumococcal CAP in many studies, it has low sensitivity and premedication with antibiotics reduces it further. The observed sensitivity (57.1%, 95% CI 18.4% to 90.1%) and specificity (92.5%, 95% CI 90.6% to 94.1%) for the BinaxNOW urinary antigen detection test in our study are comparable to sensitivities of 75% to 88% 49,[156][157][158][159][160] compared with blood culture (or culture of blood and pleural aspirate) in previous studies. The BinaxNOW POCT has a high specificity, in excess of 90%, and contributed to a reduction in the spectrum of antibiotic cover of 41 of 474 episodes of CAP in one recent study.…”

Clinical Usefulness of Streptococcus pneumoniae Urinary Antigen in Patients Hospitalized with Non-Nosocomial Pneumonia

“…The described data are inferior to those previously described in the literature 2 . These results may be due to low quality products collected in the emergency department and inclusion of non-septic patients.…”

“…According to the current recommendations of the Infectious Diseases Society of America (IDSA), it is good practice to investigate the etiologic agent responsible for the pneumonia, because it allows a significant change in the treatment, promotes the rational use of antibiotics, reduces costs, adverse effects and resistance 2,3 .…”

Pulmonary Manifestations of HIV Disease

“…The urinary pneumococcal antigen test is a rapid test with good test performance parameters including a sensitivity in the region of 81%, specificity 98%, positive (PPV) and negative predictive values (NPV) 98%, and 82%, respectively 137 . The urine pneumococcal antigen test may be positive many weeks after the pneumonia has resolved 128 . The urinary antigen test for Legionella pneumophila sero group 1 has a sensitivity of 70-90% and a specificity of nearly 100% for the detection of this pathogen 129…”