Meningitis is one of the major lethal infectious diseases especially for the children in developing countries .It is not always possible and often very difficult to distinguish between bacterial and viral meningitis according to CSF findings, which is not accurate 100% and leads to unnecessary antibiotic usage , So We tried to find a useful 'bedside' decision-making tool, based on laboratory results readily available at the emergency department .

Meningitis, since described first in the year 1805, has been one of the major lethal infectious diseases especially for the children in developing countries .Bacterial meningitis, still one of the most life-threatening potentially serious infection worldwide of high morbidity and mortality, it is more prevalent in children and its timely and early differentiation from viral meningitis has a huge impact on the treatment of affected patients with 1.2 million cases per year, resulting in 135 000 deaths.

Case fatality rates for bacterial meningitis range from 4.5% in developed countries to 15-50% in developing countries.

A further 15-20% of survivors sustain neurological sequelae , Including presistant hearing loss and neurologic disability.

The mortality from meningitis is close to 100% in untreated individuals and can still be up to 40% in children who received appropriate antibiotic therapy in developing countries .

Most of these fatalities occur within 72 hours of admission to the hospitals. Neurological outcome and survival depends largely on damage to central nervous system prior to effective antimicrobial therapy. Quick diagnosis and effective management is the key to success . bacterial meningitis commonly caused by N.meningitis , strept.Pneumonia, H.influenza & Group B streptococci. but viral meningitis caused by Enteroviruses 50% , Herpes viruses , respiratory viruses & others itis transmitted by person to person contact through respiratory secretions or droplets.

Diagnostic dilemma is due to large spectrum of signs and symptoms and majority of children who report to hospital have already been treated with inadequate doses of antibiotics and present with atypical features of CSF examination. The only reliable method is bacterial culture of CSF which is positive only in 30-60% and it requires at least 48-72 hrs to be positive. Hence, a test that might help to diagnose and differentiate meningitis earliest is more useful to decrease expensive antibiotic for prolonged duration causing financial burden to poor parents and lengthening of hospital stay .

Hence this study will be conducted to determine and compare the sensitivity, specificity, predictive values and likelihood ratios of such laboratory tests used for diagnosing and differentiating between bacterial and viral meningitis are levels of CRP in CSF and serum procalcitonin with special reference to CSF-CRP level measured by reagent nephelometric method by BN prospec seimense, the major advantage of this method is it's rapid easy two minute reaction time . Serum procalcitonin level for all patient suspected with meningitis measured by chemilumensce on cobas E411 or by ELISA (enzyme linked immunoassay) using blood culture and gram stain as gold standard test.

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Inclusion Criteria:

• Patients at pediatric emergency care unit characterized by:

  1. Age from 2 years to 18 years old.
  2. All patients with clinical features suggestive of meningitis presented with fever, convulsions and possible meningeal signs.
  3. Immuno-compermised patients or patients on steroids specially.

Exclusion Criteria:

1. Patients above 18 years old .
2. patient with acute infections at sites other than central nervous system.
3. patients with severe hepatic dysfunction .
4. patient with positive family history of metabolic disease .
5. patients known to had congenital CNS abnormality.

children at pediatric emergency care unit attending to Assuit University Children Hospital Aged from 2 years to 18 years old presented with fever, convulsions, disturbed consciousness and possible meningeal sign