A 24 year female presented with generalized weakness. Her thyroid function test is as follows. Serum T3 = Normal, T4 = Normal, TSH = 10mU/L. What is the most likely diagnosis?
(a) Primary hypothyroidism
(b) Secondary hypothyroidism
(c) Subclinical hypothyroidism
(d) Non thyroidal illness
ANS- (c) Subclinical hypothyroidism
subclinical hypothyroidism refers to biochemical evidence of thyroid hormone deficiency in patients who have few
or no apparent clinical features of hypothyroidism.
There are no universally accepted recommendations for the management of subclinical hypothyroidism, but levothyroxine is recommended if the patient is a woman who wishes to conceive or is pregnant, or when TSH levels are above 10 mIU/L.
When TSH levels are below 10 mIU/L, treatment should be considered when patients have suggestive symptoms of hypothyroidism, positive TPO antibodies, or any evidence of heart disease.
It is important to confirm that any elevation of TSH is sustained over a 3-month period before treatment is given. As long as excessive treatment is avoided, there is no risk in correcting a slightly increased TSH.
Treatment is administered by starting with a low dose of levothyroxine (25–50 μg/d) with the goal of normalizing TSH. If levothyroxine is not given, thyroid function should be evaluated annually.