Thyroxine binding globulin is one of three proteins in the human body that is responsible for transporting the thyroid hormone to different parts of the human body. A deficiency in this globulin is an acquired or inherited disorder which typically does not cause any health problems. The hormone thyroid is an essential part of growth regulation, brain development and the bodys metabolism (the speed at which the human body reacts to chemicals). In general the thyroid hormone circulates through the blood stream by attaching itself to thyroxine binding globulin – it follows then that if there is a deficiency of this protein then the amount of thyroid hormone in the blood system will be reduced. Diagnosis is reached through blood tests that determine what levels of thyroid hormone are in your bloodstream. A correct diagnosis is essential in order to avoid any unnecessary and potentially harmful treatments.
Binding globulin deficiency as a result of genetic defects
Inherited thyroxine binding globulin deficiency may be the result of things like genetic defects – this includes defects in the TBG gene as well as other genetic defects. Most specifically, it is a deficiency caused by a mutation in the SERPINA7 gene. The condition affects around 1 in 15,000 newborn babies and is most commonly found among Australian Aborigine people and Bedouin people of Israel. Fathers cannot pass this condition on to their sons, but they can give it to their daughters. Mothers can be carriers to both genders of children.
Most common conditions due to binding globulin
If the thyroxine binding globulin deficiency has been acquired then it is probably due to one of the following conditions -
Hyperthyroidism – this can be diagnosed by noting the decreased amount of thyroid hormone in the bloodstream, a result of TBG deficiency.
Chronic renal failure
Chronic liver disease
Severe systemic illness
Certain drugs can also increase the likelihood of developing TBG deficiency. These mainly include androgens and glucocorticoids.
Sufferers of thyroxine binding globulin deficiency do not appear to develop any specific traits connected with the conditions and there appears to be no incidence rate or reported deaths associated with it – the morbidity and mortality for patients with acquired thyroxine binding globulin deficiency is usually related to their severe underlying illness. There have been reported cases of misdiagnosis resulting in unnecessary and harmful treatment in patients thought to be in a hypothyroid state when in fact their condition was thyroxine binding globulin deficiency.
It is essential that those with inherited thyroxine binding globulin deficiency are fully aware of their condition so that they can inform their physicians and avoid any dangerous misdiagnosis that could occur and potentially cause damage to organs and health.