Endocrine Abstracts

Introduction: The change in thyroid parameters is described in the case of antiepileptic treatment in the pediatric population, due to interferences within the hypothalamo-pituitary-thyroid axis and due to the increase in the rate of hepatic metabolism of thyroid hormones.

Case presentation: We present the case of a 10-year-old boy who addressed our outpatient pediatric endocrinology department for endocrine evaluation in the context of weight growth about 10 kilograms, dry skin, poor growth velocity and low school performance, that developed progressively over the last 3 months. The patient associated a history of partial seizures and motor tics controlled with treatment with oxcarbazepine 900 miligrams per day for 1 year. The parents denied daily administration of biotin, corticosteroids, etc. On physical examination the child was overweight (87 percentile body mass index), had a normal height for his age (+0.16 S.D.) without active stretch marks, without hirsutism and with Tanner I prepubertal status.

Thyroid hormone profile indicated central hypothyroidism with low levels of thyroid stimulating hormone of 0.56 microUi/ml (normal range 0.6–4.5 microUi/ml) and decreased values for free thyroxine (FT4) and free triiodothyronine(T3) of 0.82 pmol/l and 75 ng/dl (normal range 0.89–1.34 pmol/l, respectively 80–200 ng/dl). The patient had normal laboratory evaluation, including liver and kidney function, complete blood count, prolactin and cortisol levels. The thyroid ultrasound indicated a homogenous structure, normal dimensions of thyroid gland and a normal vascularization. The magnetic resonance of the brain and the hypothalamo-pituitary region was within normal limits. The patient was started on levothyroxine therapy and clinical symptoms have improved together with the increase of free thyroxine values.

Conclusions: In conclusion, we present the case of a patient diagnosed with central hypothyroidism associated with oxcarbazepine treatment, emphasizing that oxcarbazepine can interfere with thyroid hormones axis.

Keywords: central hypothyroidism, oxcarbazepine.