Van Wyk Grumbach syndrome

The Van Wyk Grumbach syndrome is characterized by chronic hypothyroidism with high levels of thyroid-stimulating hormone (TSH), delayed bone age, precocious puberty but lacking pubic and axillary hair growth .

Epidemiology

The acquired form of hypothyroidism is seen in children caused by chronic autoimmune thyroiditis. Its prevalence is ~2.5% (range 1.3-4%) in children .

Clinical presentation

Clinical presentation is typically with precocious puberty with signs of early menarche and breast development .

Pathology

The most common cause of hypothyroidism is regarded as autoimmune thyroiditis . The excessive production of thyroid-stimulating hormone (TSH) stimulates follicle-stimulating hormone (FSH) receptors on ovaries that in turn results in the increased production estrogen. The estrogen induces the development of secondary sexual characteristics .

In males, the direct effect of hypothyroidism on prepubertal testis can result in macro-orchidism .

Radiographic features

Plain radiograph

Delayed bone age determined from the appearances of epiphysis in x-rays of wrist and hand. The useful method is the Greulich and Pyle's atlas of bone ages, comparing ossification centers of healthy children with the patient .

Treatment and prognosis

Thyroxine replacement therapy is used to treat the signs and symptoms .