Brain injury markers: S100 calcium-binding protein B, neuron-specific enolase and glial fibrillary acidic protein in children with diabetic ketoacidosis.

BACKGROUND: To investigate serum levels of brain injury markers in diabetic ketoacidosis (DKA) and the relation of these markers with clinical and radiological findings of brain injury and laboratory results.

METHODS: Twenty-nine patients with DKA, 30 with type 1 diabetes mellitus (T1DM), and 35 healthy children were included. Clinical and laboratory findings, and the Glasgow Coma Scale (GCS) were recorded. In the DKA group, neuron-specific enolase (NSE), S100 calcium-binding protein B (S100B) and glial fibrillary acidic protein (GFAP) levels were measured at baseline and 6 and 12 hours after treatment. Magnetic resonance imaging was performed in the DKA group to demonstrate any brain injury.

RESULTS: No clinical or radiological findings of brain injury were found in any of the patients with DKA. In the DKA group, S100B was significantly higher than the healthy control and T1DM groups, while GFAP and NSE levels were not different from controls and T1DM patients. No significant differences were found in GFAP, NSE and S100B levels according to severity of DKA, diabetes duration and GCS.

CONCLUSION: NSE and GFAP levels do not increase in DKA patients without overt brain injury. Elevated levels of S100B, which is also synthesized from non-neuronal tissues, might arise from peripheral sources. A lack of concurrent increase in serum levels of these brain injury markers might result from the yet intact blood brain barrier or a true absence of neuronal damage. In order to reveal subclinical brain injury related to DKA, there is a need for studies concurrently assessing neurocognitive functions.