Usefulness of Urinary Antigen Detection by an Immunochromatographic Test for Diagnosis of Pneumococcal Pneumonia in Children

Abstract

We evaluated an immunochromatographic assay detecting pneumococcal antigen in urine samples from children diagnosed with pneumococcal pneumonia. The sensitivity and specificity of the immunochromatographic test with nonconcentrated urine (NCU) were 86.7 and 62.9%, respectively; with concentrated urine (CU), they were 100 and 11.7%, respectively. Pneumococcal antigen was also detected in 42.5% of NCU and 87.1% of CU samples from nasopharyngeal carriers. This is a nonspecific test for the diagnosis of pneumococcal pneumonia in children, particularly the very young.Streptococcus pneumoniae is presumed to be the main bacterial cause of community-acquired lower respiratory infections among children (2, 9, 12). The severity of pneumococcal diseases heightens the importance of the identification of children with pneumococcal infections (10). Detection of S. pneumoniae antigen in urine samples is an alternative for the diagnosis of pneumococcal pneumonia. We assessed the utility of a rapid immunochromatographic membrane test (ICT) (Binax Now S. pneumoniae urinary antigen test; Binax, Portland, Maine) for detecting C-polysaccharide (PnC) S. pneumoniae antigen in urine samples from children diagnosed with pneumococcal pneumonia. We also studied whether the status of pneumococcal nasopharyngeal carriage could interfere with the performance of the ICT.(Part of this study was presented at the 12th European

Diagnosis of Invasive Pneumococcal Infection by Serotype-Specific Urinary Antigen Detection

“…First, performing multiple ELISAs on each sample is relatively labor intensive, although some automation of the process would be relatively straightforward, and the assays could potentially be "multiplexed" using coated-bead suspension array technology as described previously for the assay of antibodies against pneumococcal capsular polysaccharides (17). Second, previous studies have demonstrated that detectible pneumococcal C polysaccharide is present in the urine of healthy infants with upper respiratory tract colonization (4,5,8). While there is currently no evidence that capsular polysaccharide is similarly present in the urine of colonized infants, it would not be surprising if this were the case, and this requires further investigation before these ELISAs could be recommended in a pediatric population.…”

“…A number of publications have described antigen detection assays (7,9). Several have targeted C polysaccharide in urine, and recent evaluations have reported favorable sensitivity and specificity data for commercial kits using this strategy in adults (13,21), although they lack specificity in children (4,5). These kits do not, however, give information on the capsular serotype of causative organisms, data which would be valuable for epidemiological purposes and for assessing the extent of postvaccination serotype replacement among pneumococci causing invasive infections.…”

Detection of Mycobacterial Lipoarabinomannan with A Monoclonal Antibody Qualitative ELISA in Urine of Tuberculous Meningitis Patients

“…(4) The most severe form of tuberculosis is tuberculous meningitis. Diagnosis of tuberculous meningitis is difficult and relied on history, physical examination, laboratory and radiological capsulatum antigen (17,18), Streptococcus pneumoniae (19,20) and Legionella pneumophila (21). It has been shown that the sensitivity of the enzyme-linked immunosorbent assay (ELISA) method for LAM in unconcentrated urine tuberculosis patients without HIV infection was 7%.…”

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

“…It has sensitivity of 80% or more in adults and children when positive blood cultures are used as reference standard. [50][51][52][53][54] Rationale for the study…”