Extreme hypervascularity and bruit in a treated hypothyroid goitre.

A child in early puberty, who presented with a modestly enlarged thyroid gland and confirmed hypothyroidism, was successfully treated with thyroxine. Subsequently a widespread bruit developed in the neck caused by bilaterally dilated superior thyroid arteries with increased blood flow to the goitre. At thyroidectomy, histopathology showed features of dyshormonogenesis with greatly increased vascularity and widespread diffuse staining for vascular endothelial growth factor (VEGF). It is likely that VEGF in association with other angiogenetic factors was associated with enlargement of the gland and its hypervascularity.