Investigation of Positive Streptococcus pneumoniae Urinary Antigen Test Results in a Korean University Hospital.
10.5145/KJCM.2010.13.1.14
- Author:
In Suk KIM
1
;
Eun Ha KOH
;
Sunjoo KIM
;
Kook Young MAENG
;
Hyun Ju JUNG
Author Information
1. Department of Laboratory Medicine, Institute of Health Sciences, Gyeongsang National University School of Medicine, Jinju, Korea. sjkim8239@hanmail.net
- Publication Type:Original Article
- Keywords:
Streptococcus pneumoniae;
Bacterial antigens;
Urinary antigen test;
Cross-reactivity
- MeSH:
Antigens, Bacterial;
Clinical Laboratory Information Systems;
Emergencies;
Hospitalization;
Humans;
Medical Records;
Pneumococcal Infections;
Pneumonia;
Pneumonia, Pneumococcal;
Retrospective Studies;
Sputum;
Streptococcus;
Streptococcus pneumoniae;
Urinary Tract Infections
- From:Korean Journal of Clinical Microbiology
2010;13(1):14-18
- CountryRepublic of Korea
- Language:English
-
Abstract:
BACKGROUND: The Streptococcus pneumoniae urinary antigen test (SPUAT) (Binax Now, USA) was developed for detecting polysaccharide C in urine samples for rapid diagnosis of pneumococcal pneumonia, the most common cause of community-acquired pneumonia (CAP). To validate positive results of these tests, we retrospectively investigated all positive results obtained from the emergency room of a Korean university hospital among patients with suspected CAP. METHODS: One hundred twenty-three positive SPUAT results were abstracted and analyzed from the authors' laboratory information system among the SPUAT results performed from 1,143 pneumonic patients admitted from the emergency room of a university hospital between 2007 and 2008. Medical records, including conventional microbiologic analysis results, were reviewed in detail for all positive test results. RESULTS: Among 123 patients with the positive SPUAT results, 24 patients were excluded due to hospitalization history during the preceding month. Nine of 99 patients (9.1%) with suspected CAP had confirmed pneumococcal pneumonia upon conventional sputum or blood culture. Thirty-five positive results (35.4%) showed other microorganisms upon conventional methods, which might be due to possible cross-reactivity. Among those, 23 positive results were considered bacterial pneumonic agents, and 12 positive results were regarded as urinary tract infection strains or contaminating agents. Fifty-five positive SPUAT results (55.6%) showed negative conventional microbiologic growth, and some positive SPUAT results might be caused by true pneumococcal infection although without cultural evidence. CONCLUSION: Our retrospective study demonstrated that a positive SPUAT result typically does not agree well with conventional culture methods, suggesting that the value of a positive SPUAT result in etiology determination may be limited under practical conditions in a university hospital.
