Neuron-Specific Enolase In Cerebrospinal Fluid As A Neurochemical Marker For Brain Damage In Childhood Acute Lymphoblastic Leukemia

Neuron-specific enolase (NSE), an isoenzyme of the glycolytic enzyme enolase, is predominantly present in the neuronal soma but is also present to a lesser degree in axons. NSE in CSF is a reliable marker of neuronal damage. And it had previously been shown to signal brain damage after hypoxic –ischemic and traumatic injury. It had been analyzed in various neurodegenerative, inflammatory and infectious diseases, both in blood and in CSF. Recent studies reported that during induction treatment of ALL, uneven regional cerebral blood flow with hypo perfusion of cortical areas was reported. This was seen together with leakage of neuron-specific enolase (NSE) into the cerebrospinal fluid. Regional hypo perfusion causing oxidative stress or direct toxic effect of the chemotherapy might cause brain damage.Objective: The aim of the present study was to show if there is a significant relation between induction treatment of ALL using intrathecal injection as in the protocol of treatment and the elevation of NSE levels in the CSF.Methods: The study included 30 children newly diagnosed ALL. Children in this study were subjected to history taking, clinical examination, routine investigations and a specific investigation to measure the CSF levels of NSE before induction treatment was started (day 0), and with every IT injection of MTX (day 7, day 14 and day 28).Results: The results of the present study showed significant rise in the levels of NSE estimated in the CSF especially at day 7, however the levels tend to regress later on in samples withdrown at days 14 and 28 respectively but always remained higher than before induction levels. This strongly suggest the occurrence of some sort of brain damage most likely following uneven regional hypo perfusion to the brain. The results of this study also showed no significance relation between the age, sex, risk stratification of the cases and the pattern of rise of NSE, moreover FAB classification and immunophenotyping had no significant effect on the results of NSE levels.Conclusion: Increased NSE in CSF during induction therapy in children with ALL can be interpreted as early sign of brain damage.