A Study to Assess the Validity of Estimation of Serum Ostase Level in Hyperthyroid and Hypothyroid Cases

One of the more specific assessments of the metabolic status of bone in normal and in disease conditions is the measurement of bone specific alkaline phosphatase or ostase. The measurement of serum ostase has several advantages over the measurements of other bone parameter. Because of its relatively long half-life, in-vivo (1 to 3days), it is relatively unaffected by diurnal variation.

To find the correlation of serum ostase level in hyper and hypothyroid cases and also to study the validity of routine estimation of serum ostase in hyper and hypothyroid cases so as to monitor the base level bone health on presentation.

Serum ostase level was studied in 74 patients with disorder of thyroid function. Serum ostase level, Thyroid Stimulating Hormone (TSH), FT3, FT4 levels were estimated by chemiluminescent technique. The instrument used was Beckman- coulter Access 2. A total of 39 patients were hypothyroid, 31 were hyperthyroid and 4 patients had subclinical hyperthyroidism.

The serum ostase level was found to be elevated above 40 μg/L in 26 of the cases and above 16 μg/L but below 40μg/L in 5 cases of hyperthyroidism along with decrease in Bone Mineral Density (BMD). Serum ostase level was found to be directly proportional to the serum FT3 level (Normal range of serum ostase is 8-16 μg/L).

From this study, an inference can be drawn that a routine estimation of serum ostase level in hyperthyroid cases will help in proper monitoring of decrease bone turnover as indicated by increase serum ostase level. Besides, the estimation of serum ostase level in hyperthyroid cases it is found to be valid in this study, which can turn to be an important guiding parameter to the treating physician to formulate necessary protocols and guidelines for prophylaxis, treatment and to monitor the response to therapy in cases of reduced bone turnover related to hyperthyroid state.