Abstract
INTRODUCTION: Primary hypothyroidism is a well-known cause of poor linear growth in children. A rare finding with profound or long-standing disease is anterior pituitary enlargement (pituitary pseudotumor). This case highlights this uncommon finding, discusses clinical situations in which gradual dose escalation of levothyroxine may be advisable and reviews adjuvant therapies that have been previously attempted to improve final height in the setting of profound hypothyroidism. CASE PRESENTATION: We report the case of a 13-year-old Hispanic girl initially evaluated for poor linear growth and delayed puberty, and found to have pituitary enlargement secondary to profound primary hypothyroidism. Treatment with progressive doses of levothyroxine normalized her symptoms and led to complete resolution of her pituitary findings, but she then rapidly progressed through puberty, achieving an adult height of only 142cm, significantly below her calculated mid-parental height. CONCLUSIONS: In cases of severe primary hypothyroidism with prolonged elevation of thyroid-stimulating hormone and pituitary pseudotumor, gradual replacement of thyroid hormone with slowly escalating doses of levothyroxine may be beneficial to prevent complications of therapy. Early recognition and treatment of hypothyroidism during childhood is essential for normal growth, as final height is invariably compromised in children with prolonged disease. Additional study is needed to determine the potential beneficial effects of gonadotropin-releasing hormone agonist and recombinant human growth hormone treatment in this setting.