Ultrastructure of platelets in Bernard-Soulier syndrome

The platelets of a patient with the Bernard-Soulier syndrome were studied by electron microscopy. The main abnormalities were the presence of giant and often round platelets, hypertrophic and frequently widely dilated open canalicular system, disorganized microtubules, and platelets with sparse or absent granulation. Although well defined, these ultrastructural morphologic aberrations are not considered diagnostic or pathognomonic of the syndrome.