Enzymatic changes in serum and cerebrospinal fluid in neurological injury

Abstract

✓ Enzymatic determinations in serum and cerebrospinal fluid (CSF) of creatine phosphokinase (CPK) and its isoenzymes, lactic dehydrogenase (LDH) and its isoenzymes, and glutamic oxaloacetic transaminase (GOT) were performed on patients with closed head injury with Glasgow Coma Scale (GCS) scores of 3 to 15. The purpose of the work was to study the usefulness of these determinations as a biochemical index of brain injury. Detailed analysis of serum determinations on 139 patients demonstrated a prognostic correlation for only the CPK1 isoenzyme. The presence of the CPK1 isoenzyme correlated with the degree of head injury (as indexed by the GCS) and with the ultimate outcome. Although the presence of the CPK1 isoenzyme was a foreboding sign, it was not consistently present even with severe head injury, and its presence was not invariably associated with poor outcome. Therefore, serum enzymatic determinations have an inadequate sensitivity and specificity for use as an index of neurological trauma. Fifty-seven patients had CSF enzymatic determinations, and each of the enzymes studied was correlated directly with GCS and with the ultimate outcome. Within the subgroup of severely head-injured patients with a GCS score of 3 to 7, only the CPK1 and LDH1 isoenzymes correlated with the degree of head trauma and outcome. The CPK1 isoenzymes were not detectable in CSF from control patients, but were invariably present following head trauma. These CPK1 isoenzymes in the CSF were particularly useful in that they appeared in the acute course and were subsequently absent unless secondary injury to the brain occurred causing additional neurological damage. Secondary injuries due to delayed hemorrhage, infarction, hypoxia, or pathological evaluations of intracranial pressure were readily detected. The LDH1 isoenzyme is present in the CSF from normal patients and does elevate with neurological trauma; these LDH1 isoenzymes appear to be elevated for a period of weeks to months following injury and thus are less useful in detecting secondary injuries. An attempt was made to investigate the effect of Decadron (dexamethasone) on these enzymatic changes, but no significant effect was identified. Also noted in this study was the presence of CPK1 isoenzymes in the CSF of patients with gunshot wounds to the head, spinal cord injuries, and herniation syndromes. It is concluded, therefore, that CPK1 isoenzymes in the CSF appear to be a specific marker for neurological trauma, and may be of value both in clinical practice and in clinical investigations.