title: Isospora cholangiopathy: case study with histologic characterization and molecular confirmation.
abstract: Isospora belli is an intracellular protozoan parasite that causes diarrhea worldwide and is endemic in the tropics. In the United States, it is an uncommon cause of traveler's diarrhea and a relatively rare opportunistic pathogen among the immunocompromised, particularly AIDS patients. Isospora infects the small intestine, where both sexual and asexual replication occur, and oocysts are shed in the stool. Isosporiasis of the gallbladder has also been described in AIDS patients. We report a case of diffuse biliary isosporiasis in a West African man who presented with acute illness and was found to have dilated bile ducts. He had no history of hepatobiliary disease; his HIV status was unknown. Endoscopic retrograde cholangiopancreatography demonstrated markedly abnormal intrahepatic and extrahepatic bile ducts, with radiologic findings reminiscent of primary sclerosing cholangitis. However, common bile duct biopsies revealed Isospora belli, which was confirmed by both electron microscopy and polymerase chain reaction-based molecular analysis.
authors.affiliation: Department of Pathology, Yale University School of Medicine, New Haven, CT 06520-8023, USA. zenta.walther@yale.edu
authors.forename: Zenta
authors.initials: Z
authors.lastname: Walther
authors.forename: Mark D
authors.initials: MD
authors.lastname: Topazian
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000150:complications; D000328:Adult; D000818:Animals; D000890:Anti-Infective Agents / Q000627:therapeutic use; D000977:Antiparasitic Agents / Q000627:therapeutic use; D017734:Bile Ducts, Extrahepatic / Q000469:parasitology / Q000473:pathology / Q000601:surgery; D001653:Bile Ducts, Intrahepatic / Q000469:parasitology / Q000473:pathology / Q000601:surgery; D001706:Biopsy; D002760:Cholangiopancreatography, Endoscopic Retrograde / Q000009:adverse effects; D015209:Cholangitis, Sclerosing / Q000175:diagnosis* / Q000000981:diagnostic imaging; D006801:Humans; D007549:Isospora / Q000648:ultrastructure*; D021865:Isosporiasis / Q000175:diagnosis* / Q000188:drug therapy / Q000469:parasitology*; D007559:Ivermectin / Q000627:therapeutic use; D008297:Male; D016133:Polymerase Chain Reaction; D016896:Treatment Outcome; D015662:Trimethoprim, Sulfamethoxazole Drug Combination / Q000627:therapeutic use
chemical_list: D000890:Anti-Infective Agents; D000977:Antiparasitic Agents; D007559:Ivermectin; D015662:Trimethoprim, Sulfamethoxazole Drug Combination