Clinical presentation: A 29-year-old woman was referred for evaluation of a newly discovered hypothyroidism. We first met her 2 years ago when we indicated a screening examination because her mother had hypothyroidism. At that time, she was euthyroid and the aTPO was 0 U/mL, however the ultrasound pattern was minimally hypoechogenic. We suggested yearly TSH determination, in the event of pregnancy at once.

Palpation. No abnormality.

Laboratory test: TSH 4.49 mIU/L, aTPO 1 U/mL.

Ultrasonography. The thyroid was minimally-moderately hypoechogenic. There were no discrete lesions within.

Suggestion: daily 50 microgram levothyroxine.

Comment. On our experience which is in accordance with the literature, the risk of a first degree relative of a patient with autoimmune thyroid disease for developing hypothyroidism is 2.5 times higher than the average risk. Therefore, we suggest every first-degree female relative of such patients be screened every three years and in the event of pregnancy at once.