Bile duct disorders.

Drug-induced bile duct injury related prolonged or chronic cholestasis is recognized as a common side effect of treatment with several drugs. The severity and duration of the clinical symptoms suggest that this increase in number of reports is not only related to clinician and pathologists being increasingly aware of the condition, but also may represent a true increase in incidence likely related to a time-related growing experience with newer drugs. This clinical presentation encompasses a wide variety of features that may be the source of diagnostic difficulties, especially in the cases where cholestasis occurs days or weeks after the completion of therapy. Even more puzzling is the initial picture of hepatocholangitis, which may be silent and ensuing bile duct paucity with chronic anicteric cholestasis may be another source of diagnostic difficulties in the long-term. These diagnostic difficulties suggest that some of the cases of the so-called "idiopathic adulthood ductopenia" may originate from overlooked drug induced vanishing bile duct syndrome. The pathogenesis of the syndrome remains largely unknown and the determinants of prognosis and outcome. From reproducible data obtained in different studies investigating HLA-dependent predisposition, one may assume that genetics plays a major role even if other unknown additive factors are also likely involved. Severity of initial hepatocholangitis is likely to represent another important determinant of severity and prognosis, however to be assessed in larger longitudinal studies. Therapy of large bile duct injury mimics that of primary sclerosing cholangitis. Treatment of small bile duct injury remains disappointing. Corticosteroids are invariably ineffective. Ursodeoxycholic acid as been shown to induce improvement of clinical and biochemical cholestasis in some selected cases, its efficacy being however unpredictable. Preliminary data about the natural history of the vanishing bile duct syndrome suggest that therapy might be more effective when initiated early.