Efficacy of cerebro-spinal fluid biochemistry in the diagnosis of brain insult

Abstract

Postmortem biochemical indices may provide a useful adjunct to morphological studies in the identification of antemortem brain insult. We studied 34 routine medico-legal cases categorising them into one of four diagnostic groups. There were 11 cases of head trauma, 7 of ‘hypoxia’ (3 hangings and 4 carbon monoxide or drug poisonings), 7 sudden cardiac deaths and 9 miscellaneous cases. Survival time and postmortem interval was known for each case. The degree of cranio-cerebral trauma was graded. Cerebro-spinal fluid (CSF) and vitreous humour were analysed for calcium, glucose, total proteins, aldolase, aspartate transaminase (AST), alanine transaminase (ALT), gamma glutamyltransferase (GGT), lactate dehydrogenase (LDH), creatine kinase (CK) and creatine kinase BB isoenzyme (CK-BB). CK-BB was also measured in superior vena cava serum. In CSF there was a significant correlation between the severity of cranio-cerebral trauma and levels of aldolase, CK-BB, AST, ALT and total proteins. CSF CK-BB, median units/l (range), for the groupings of head trauma, hypoxia, sudden cardiac death and miscellaneous were respectively 823 (2–3431); 96 (2–187); 4 (2–25); 5 (1–69). Corresponding serum CK-BB levels were 240 (28–322); 390 (26–411); 180 (20–482); 79 (18–530).