Lactate Compared to Creatine Kinase as Diagnostic Marker in Generalized Epileptic Seizure

The patients of this prospective study were selected from a sample of patients who were admitted to the emergency room of the University Hospital RWTH Aachen with an unclear impairment of consciousness. Only patients who later on were diagnosed as having experienced a GTCS or a syncope and whose serum lactate concentrations had been measured within 2 hours after the event were enrolled in the study. The investigators compared the specificity and sensitivity of the serum lactate concentrations at admission with the CK concentration at admission and the CK follow-up taken 10 to 48 hours after the event.

The values at admission were compared between patients from whom a blood sample was collected within 60 minutes after the event, and those from whom a blood sample was collected within 61-120 minutes after the event.

The comparison of initial lactate concentrations at admission with CK levels 10 - 48 hours later could only be performed on part of the patient collective because the other patients were already discharged at this time-point and could therefore not be included.

The initial blood samples were taken at patient arrival in the emergency room. The follow up was performed during the inpatient stay.

Serum lactate and CK concentrations between patient groups were statistically compared with a Mann-Whitney-U test. We defined cut-off values and their sensitivity and specificity by Receiver Operating Characteristic (ROC) analysis.

Inclusion criteria

Patients with generalized tonic-clonic seizures and syncopes and whose blood samples were taken within 2 hours after the event

18 years or older

Observed seizure

Time of the event before admission was known

Diagnosis of an epileptic seizure or syncope had been entered in the final discharge report

Exclusion criteria

Prisoner

Age < 18 years old

Competing explanations for serum lactate or CK elevation e.g. shock or trauma

Lack of capacity for consent