Adenylate kinase values in cerebrospinal fluid as a marker to predict neurological outcome in children with meningitis

Abstract

Meningitis in children is a common and serious disease. Bacterial and tuberculous meningitis often lead to neurological complications. A sensitive marker to predict brain damage in children with meningitis could be of great importance. Frithz F et aI, 1982 suggested that increased adenylate kinase values could indeed be used as a marker for brain damage. Adenylate kinase (AK) is an enzyme present in brain tissue. Low concentrations are present in normal cerebrospinal fluid (CSF) « 1 uti). Increased concentrations were found in cases of ischemic brain damage (Frithz et aI, 1982), malignant brain tumours (Ronquist G et aI, 1977) and bacterial meningitis. As AK has a low molecular weight (22,00 Daltons), in comparison to other kinases (40,000 Daltons) it is one of the first enzymes that can be detected in the CSF after brain damage and it can thus be used as a reliable marker for brain cell damage. The aim of this study was to quantify the AK values in CSF of children with bacterial and tuberculous meningitis and to evaluate their use to predict the neurological outcome in children with bacterial and tuberculous meningitis. Eighty eight children with tuberculous meningitis (TBM) and thirty three children with bacterial meningitis were included in the study. Sixty children with suspected meningitis but who were later diagnosed with urinary tract infections, gasto-enteritis, bronchitis, febrile convulsions or other non-neurological infections were used as controls. The results showed raised AK values in the CSF of children with bacterial- and TB meningitis. There was a statistically significant difference of AK values between stage III and II TBM AK values in patients at week 1 after diagnosis (p=0,03). There was also a statistically significant correlation between CSF AK values and lactate concentrations (P=0,001) which reflected hypoxic brain metabolism. Although AK values did not always correlate directly with the patients’ clinical outcome, there is proof that increased AK values in CSF can be used to predict neurological outcome.