Could Abnormally High TSH Levels While Being Hypothyroid Indicate Macro TSH?

Hi Dr. Topiwala, I am a 32 year old woman. I had been diagnosed with hypothyroid 9 years back. Since then I am on synthetic hormones. (No history of thyroid disorder from either of the parents side.) TSH level within specified limits now. Few days back my younger brother(3years younger to me) is also being diagnosed with hypothyroid. His TSH levels are abnormally high, 255.1. He on synthetic hormone of 100 mg for last 6 days. Please reply if his case is of high molecular weight forms (macro TSH)? And if this is the case what should be the line of treatment for him.