Validity of carbohydrate deficient transferrin and other markers as diagnostic aids in the detection of alcohol related seizures

Objective-The role of alcohol misuse in the genesis of seizures is probably often undetected. The aim was to investigate the utility of carbohydrate d eficient transferrin (CDT) compared with other biomarkers and clinical exam ination in the diagnosis of alcohol related seizures. Methods-The study included consecutively 158 seizure patients-83 men and 75 women-with mean age 45 (16-79) years. Seizures related to alcohol use were identified by a score greater than or equal to 8 in the alcohol use disord ers identification rest (AUDIT positive). AUDIT was applied as the gold sta ndard to which sensitivity and specificity of the various markers were rela ted. Blood samples were obtained from 150 patients on admission and analyse d for ethanol, liver enzymes, and CDT, using AXIS Biochemicals' %CDT-TIA ki t. Results-53 patients (34%) were AUDIT positive. Using the commonly applied d ecision value for %CDT of 5.0%, a sensitivity of 41% and a specificity of 8 4% were obtained. Analysis of receiver operator characteristics (ROC) curve s disclosed an optimal cut off value for %CDT of 5.4%, which yielded a sens itivity of 39% and a specificity of 88%. At, specificity of 80%, the sensit ivity was 43% for %CDT and 26% for GGT. The %CDT sensitivity was markedly h igher for men than for women. Compared with GGT, ASAT, ALAT, and ASAT/ALAT ratio, CDT was the best single biomarker for alcohol related seizures. Howe ver, even in the subgroup of withdrawal seizures, the sensitivity level bar ely exceeded 50%. Clinicians scored alcohol as the main cause of the seizur e in only 19 cases (12%). In 38 (24%) cases, clinicians suspected that alco hol had a role (sensitivity of 62% at a specificity of 89%). Their ability to identify AUDIT positive patients was better than that of any biomarker, but many cases were missed. Agreement of clinicians' scores to CDT was only fair (kappa=0.28). CDT concentrations were significantly increased among a lcohol abstaining patients on enzyme-inducing antiepileptic drugs. Six out of 16 patients with false positive CDT results were exposed to such drugs. Conclusions-CDT is not recommended as a Stand alone marker for alcohol rela ted seizures, but may provide a useful contribution to the overall diagnost ic investigation of seizures. Confirmatory studies are needed as to the app arent vulnerability of CDT to antiepileptic drugs.