الفهرس 
PneumoniaOnly 14 pages are availabe for public view
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Abstract
Community-acquired pneumonia is a common potentially serious pediatric infection. It is one of the five leading causes of mortality among children in developing countries and accounting for approximately three million deaths per year worldwide.
Using ”state-of-the-art” diagnostic testing, a bacterial or viral cause of pneumonia can be identified in 30-50 %”of children with CAP. Etiologic diagnosis is particularly challenging in children because bacterial and viral pneumonia cannot be differentiated on the basis of patient’s characteristics or radiographic findings. In addition, appropriate specimens can rarely be obtained from the lower respiratory tract, as children are not able to expectorate efficiently.
Recent studies using modern microbiologic diagnostic tools have identified Streptococcus pneumoniae as a common cause of invasive bacterial infection in children and a frequent cause of community-acquired pneumonia in 37–46% of patients.
However, children are frequently colonized by SP in the nasopharynx, and consequently, the nasopharyngeal cultures can be positive as a result of this colonization. Direct culture of lung tissue is invasive and rarely performed. Blood culture and pleural culture are considered indicative of the pneumonia etiology, but they lack sensitivity. Pneumococcal PCR test is sensitive but is very expensive, needs high technical skills and is not readily available in low resource countries.
Therefore, the identification of the causative agent remains challenging in children with CAP. The lack of a standard for the etiologic diagnosis of pneumonia remains an unresolved issue.
The aim of this study was to evaluate the diagnostic performance of BinaxNOW® S. pneumoniae UAT for early detection of S. pneumoniae directly from urine specimens. It is a rapid non-invasive immunochromatographic test that detects the C polysaccharide cell wall antigen (common to all strains of SP) and it can suggest a diagnosis of SP infection within 30 minutes.
This study was carried on a total of 80 children less than 14 years old, 60 of them hospitalized with CAP (proved both clinically and radiologically) in Pediatric Department at Ain Shams University Hospitals during the period from January 2015 to July 2015. The other 20 were healthy children (Controls) excluding those with positive urine culture or respiratory infection during the previous 10 days. There was no statistical significant difference in gender or age between cases and controls.
BinaxNOW® S. pneumoniae UAT was performed for both cases and controls. All cases were tested for TLC, CRP, serum sodium level and blood culture which was the reference method for diagnosis of Pneumococci.
In this study, blood culture was positive in 9 cases; 2 of them (3.3 %) were positive for Streptococcus pneumoniae and 7 were positive for other organisms.
BinaxNOW® UAT was positive in 6/60 (10%) of cases; 2 of the them were positive for S. pneumoniae by blood culture and the other 4 positive UAT cases showed negative blood cultures. Also, Pneumococcal UAT was positive in 1/20 (5 %) in control group. The Diagnostic validity of UAT showed high sensitivity (100%) and high specificity (93.1%) in detecting pneumococcal pneumonia.
It was observed that the 2 positive S. pneumoniae blood culture cases had CRP >100 mg/L and high total leucocytic count. Hyponatremia was present in one case of positive S. pneumoniae blood culture.
The combined value of UAT and serum sodium level was found to be positive in 2/58 non-S. pneumoniae blood culture cases (96.6%) and 2/2 of S. pneumoniae blood culture cases (100%). This combination increased the diagnostic efficacy from 93.3% to 96.7%, PPV significantly improved from 33.3% to 50% and also, the specifity increased from 93.1% to 96.6%.