Van Wyk-Grumbach syndrome and oligosyndactyly in a 6-year-old girl: a case report.

Background: Van Wyk-Grumbach syndrome refers to the development of isosexual precocious pseudopuberty and multicystic enlarged ovaries in the presence of hypothyroidism and delayed bone age. It is a rare presentation of untreated hypothyroidism. The prepubertal response in Van Wyk-Grumbach syndrome is always isosexual and mediated by very high thyroid-stimulating hormone levels acting through the follicle-stimulating hormone receptors inducing a follicle-stimulating hormonal effect.