ESPE Abstracts

Background: Primary hypothyroidism is frequently associated with delayed puberty. However, precocious puberty is known to occur in some rare cases of hypothyroidism untreated for a long time. Differently from the cases suffering from precocious puberty due to other causes, linear growth and bone age are retarded in children developing precocious puberty associated with hypothyroidism. There are no definite data about the incidence of precocious puberty associated with hypothyroidism. Knowledge about the long-term follow-up of these patients is still limited.

Objective and hypotheses: Untreated hypothyroidism can cause menarche even at an early age.

Method: A female patient with Down syndrome aged 2 years and 9 months was referred with the symptom of vaginal bleeding continuing for 1 week. In her history, there were no symptoms suggesting trauma, foreign body, urinary tract infection or intracranial mass. The patient exhibited the phenotypic features of Down syndrome and her height and weight were within 5–25% percentiles and 25–50% percentiles, respectively, regarding the growth curves generated for children with Down syndrome. Breast development was at Tanner stage 3 bilaterally, and she had no axillary or pubic hairs. Suprapubic ultrasonography revealed cystic lesions in the right lower quadrant and left adnexial region.

Results: She was diagnosed with Hashimoto thyroiditis hypothyroide fase as result of the tests and was started on Na L-thyroxine replacement therapy. İn our patient, all examination findings relevant to precoccious puberty, laboratory parameters and adnexial cystic lesions returned to normal in the sixth month of the treatment.

Conclusion: Hypothyroidism is common in childhood due to many reasons. However, premature menarche is a rarely seen clinical presentation of hypothyroidism. Contrary to the other cases of precocious puberty due to other reasons, linear growth is stunted and bone age is retarded. This knowledge alone is enough to draw attention once more to the importance of monitoring the growth curves of children.