[Serum enzymes in hypothyroidism]

The following parameters were studied in 27 newly diagnosed and not treated patients with primary hypothyroidism: TTH, creatine kinase (CK) with MB isoenzyme, lactate dehydrogenase (LDH) with isoenzymes LDH1 and LDH5, aspartate aminotransferase (ASAT) and alanine aminotransferase (ALAT) before and after 20-day substitutive therapy. It has been established that the enzymes were increased in about 60% of the untreated patients, and the typical enzyme constellation for hypothyroidism consisted of CK with MB isoenzymes, ASAT and LDH1. The myocardial isoenzymes were normalized within the period of substitutive therapy. The enzymes were established to be elevated only in the patients that had increased CK. The follow up of the above enzyme constellation before and during the initial phases of the treatment of hypothyroidism could provide considerable possibilities of differential diagnosis with ischemic heart disease, often manifested during that period. The determination of CK in advance would be a screening determining the necessity of studies on the enzyme constellation.