rifampin and Cholangitis--Sclerosing

Topics: Aged; Antibiotics, Antitubercular; Blood Coagulation Disorders; Cholangitis, Sclerosing; Female; Humans; Male; Middle Aged; Pruritus; Rifampin; Risk Factors

Norursodeoxycholic acid (norUDCA) exhibits efficient anti-cholestatic properties in an animal model of sclerosing cholangitis. norUDCA is eliminated as a C(23)-ester glucuronide (norUDCA-23G) in humans. The present study aimed at identifying the human UDP-glucuronosyltransferase (UGT) enzyme(s) involved in hepatic norUDCA glucuronidation and at evaluating the consequences of single nucleotide polymorphisms in the coding region of UGT genes on norUDCA-23G formation. The effects of norUDCA on the formation of the cholestatic lithocholic acid-glucuronide derivative and of rifampicin on hepatic norUDCA glucuronidation were also explored. In vitro glucuronidation assays were performed with microsomes from human tissues (liver and intestine) and HEK293 cells expressing human UGT enzymes and variant allozymes. UGT1A3 was identified as the major hepatic UGT enzyme catalyzing the formation of norUDCA-23G. Correlation studies using samples from a human liver bank (n = 16) indicated that the level of UGT1A3 protein is a strong determinant of in vitro norUDCA glucuronidation. Analyses of the norUDCA-conjugating activity by 11 UGT1A3 variant allozymes identified three phenotypes with high, low, and intermediate capacity. norUDCA is also identified as a competitive inhibitor for the hepatic formation of the pro-cholestatic lithocholic acid-glucuronide derivative, whereas norUDCA glucuronidation is weakly stimulated by rifampicin. This study identifies human UGT1A3 as the major enzyme for the hepatic norUDCA glucuronidation and supports that some coding polymorphisms affecting the conjugating activity of UGT1A3 in vitro may alter the pharmacokinetic properties of norUDCA in cholestasis treatment.

Topics: Animals; Cell Line; Cholangitis, Sclerosing; Cholic Acids; Disease Models, Animal; Esters; Glucuronides; Glucuronosyltransferase; Humans; Isoenzymes; Microsomes, Liver; Norsteroids; Polymorphism, Genetic; Rifampin

Acquired perforating dermatosis (APD) is a very rare disorder which has been described in association with systemic diseases such as diabetes mellitus, HIV infection or lymphoma. In this report we describe a patient with APD associated with sclerosing cholangitis and diabetes mellitus who was successfully treated with rifampicin. A 33-year-old Indian woman with a history of extensive pancreatic surgery, sclerosing cholangitis and insulin dependent diabetes mellitus was referred to our unit with intractable pruritus. She was treated with cholestyramine, ursodeoxycholic acid, several analgesics, UVB therapy, topical steroids, sedative antihistamines and plasmapheresis without significant improvement. Increasingly severe itching was associated with papular skin changes limited initially to the lower limbs but which later involved her entire body. Biopsy of a representative lesion showed the changes of APD. She was subsequently treated with rifampicin which produced a dramatic resolution of pruritus within 3 weeks and the skin changes progressively resolved over subsequent months. In this newly described association of APD with sclerosing cholangitis, rifampicin treatment appeared to be efficient in ameliorating pruritus and the papular skin changes typical of APD.

Topics: Adult; Antibiotics, Antitubercular; Cholangitis, Sclerosing; Female; Humans; Rifampin; Skin Diseases; Treatment Outcome

Topics: Cholangitis, Sclerosing; Humans; Male; Middle Aged; Pruritus; Rifampin