Sequential Changes in the Serum Creatine Phosphokinase Isoenzyme Activity and Correlation with Prognosis in Patients with Acute Head Injuries

Abstract

A sensitive biochemical marker for acute brain damage is important in assessing the severity of head injuries. Acute brain damage is followed by increased creatine phosphokinase (CPK) activity in the serum. The present study was undertaken to examine whether the measurement of serum levels of brain type isoenzyme (CPK-BB) and heart type isoenzyme (CPK-MB) is valuable in assessing and evaluating the clinical status of patients with acute head injuries. Fifty-seven patients with acute head injuries were studied. Fourty-four patients were male and thirteen patients were female with ages ranging from 2 to 69 years. All patients were diagnosed by computed tomography (CT) scan within three hours after head injury. Serial blood samples were drawn during the first 7 days after head injury. The Glasgow Coma Scale (GCS) for all patients was recorded on admission. Clinical outcome was assessed at the time of discharge according to the Glasgow Outcome Scale. The “good” group consisted of patients with good recovery or moderate disability. The “poor” group consisted of patients with severe disability and persistent vegetative state. The maximal serum levels of CPK-BB and CPK-MB occurred in most patients on the first day of trauma. There was a highly significant correlation between the serum levels of CPK-BB and GCS (p<0.001), whereas there was little correlation between serum levels of CPK-MB and GCS. The peak levels of CPK-BB in the “poor” and “dead” groups were significantly higher than those in the “good” group (p<0.01). Particular correlation between CT findings and serum levels of CPK-BB was found. Cases with serum levels of CPK-BB higher than 10 IU/l were associated with cerebral contusions. The major factors in the increase of serum levels of CPK-BB were associated with the severity of cerebral contusions and particular sites of the brain injuries. New lesions in serial CT scans didn't seem to be a factor in raising serum levels of CPK-BB. Serum levels of CPK-BB did not correlate with intracranial pressure. Measurement of serum levels of CPK-BB may offer useful information for making a prognosis. It seems to be a sensitive index of acute brain damage and a reliable marker of cerebral contusions.