Platelet ultra-structure study in Budd-Chiari syndrome.

Morphologic characteristics of circulating platelets were studied in 20 patients with primary Budd-Chiari syndrome (BCS) without any known etiology, using transmission electron microscopy (TEM). Significant platelet ultrastructural changes were observed in all the patients (in 10-->90% platelets) as compared to 20 normal healthy controls (in up to 4% of their platelets). The prominent changes in the platelets were paucity or absence of alpha granules, hypertrophy of the open canalicular systems (OCS) and clumping and fusion of the granules and other organelles in the centre of platelets. Some other changes observed in platelets were dilated channels of OCS, pseudopodial protrusion of cytoplasm and presence of prominent masses of glycogen particles. Platelets from 20 normal controls processed along with the patients' platelets showed only a few such abnormalities. Most of these changes observed in patients' platelets were akin to the changes observed in platelets undergoing activation. Assay of plasma beta-thromboglobulin showed significantly higher levels in all the patients (p < 0.001) further confirming on-going in vivo platelet activation with morphologic changes most likely reflecting the thrombotic process present in BCS patients.