الفهرس 
Streptococcus pneumoniae
Methods of transmission of PneumococciOnly 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%.