Biliary ultrastructural changes in the liver in a case of giant cell arteritis

A 55-yr-old Palestinian man was admitted with a 1-month history of bi-temporal headache, proximal weakness and myalgia in the lower limbs. Both temporal arteries were swollen and tortuous. There was a moderate degree of cholestatic hepatic dysfunction. Temporal artery biopsy showed typical features of giant cell arteritis. Light microscopic examination of the liver showed no significant abnormality while electron microscopic (EM) examination revealed ultrastructural damage to the bile canaliculi. The patient improved dramatically on steroid therapy with normalization of cholestatic dysfunction. EM examination of a repeat liver biopsy 8 months later showed complete reversal of the biliary ultrastructural damage. The pathogenesis of the biliary injury remains uncertain.