Diagnosis of vitamin B1 deficiency is made by
Thiamine level
Transketolase activity
Carboxylase activity
Transaminase activity
Diagnosis of Vit B1 deficiency is made by Transketolase activity.Biochemical Parameters In thiamine deficiency, blood thiamine is reduced, but pyruvate, alpha-ketoglutarate and lactate are increased. Erythrocyte transketolase activity is reduced; this is the earliest manifestation seen even before clinical disturbances.Reference: Textbook of Biochemistry by D M Vasudevan, sixth edition pg no. 392
vitamins