title: Gastrointestinal ALκ amyloidosis presenting as protein-losing enteropathy correctly diagnosed by immunohistochemistry using amyloid-type-specific antibodies.
abstract: A 54-year-old man presented with protein-losing enteropathy. Biopsies from the stomach, duodenum, ileum and colon showed deposits of amyloid. The bone marrow showed plasmacytosis. After an initial misdiagnosis of AA amyloid, a revised diagnosis of ALκ amyloidosis was made at an expert referral laboratory. Care must be taken in the use of antibodies and proper controls in the performance and interpretation of immunohistochemistry for amyloidosis. A wide panel of amyloid-type-specific antibodies must be used and interpreted in comparative mode to avoid misdiagnosis.
authors.affiliation: Department of Pathology, Manipal Hospital, Bengaluru, Karnataka, India, sanjayapai@gmail.com.
authors.forename: Sanjay A
authors.initials: SA
authors.lastname: Pai
authors.affiliation: Department of Pathology, Manipal Hospital, Bengaluru, Karnataka, India.
authors.forename: Suresh
authors.initials: S
authors.lastname: Chandra
authors.affiliation: Department of Pathology, Manipal Hospital, Bengaluru, Karnataka, India.
authors.forename: Swati
authors.initials: S
authors.lastname: Pai
authors.affiliation: Department of Gastroenterology, Manipal Hospital, Bengaluru, Karnataka, India.
authors.forename: Dinesh
authors.initials: D
authors.lastname: Kini
authors.affiliation: amYmed, Reference Center for Amyloid Diseases, Martinsried, Germany.
authors.forename: Reinhold P
authors.initials: RP
authors.lastname: Linke
mesh_terms: D000682:Amyloid / Q000276:immunology*; D000686:Amyloidosis / Q000175:diagnosis*; D000906:Antibodies / Q000276:immunology*; D003951:Diagnostic Errors; D005767:Gastrointestinal Diseases / Q000175:diagnosis*; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D011504:Protein-Losing Enteropathies / Q000175:diagnosis*
chemical_list: D000682:Amyloid; D000906:Antibodies