title: The diagnosis and characteristics of renal heavy-chain and heavy/light-chain amyloidosis and their comparison with renal light-chain amyloidosis.
abstract: Little is known about the rare entities of heavy- and light-chain amyloidosis (AHL) and heavy-chain amyloidosis (AH). Here, we report the renal and hematological characteristics, pathology, and outcome of 16 patients with renal AH/AHL (5 with AH and 11 with AHL) and compare them with 202 patients with renal light-chain amyloidosis (AL) diagnosed during the same time period. All cases were diagnosed by kidney biopsy that showed Congo red-positive deposits. Amyloid typing was done by laser microdissection and mass spectrometry (LMD/MS) on 12 patients or by immunofluorescence on four patients. All patients with renal AH/AHL were Caucasians, with a male/female ratio of 2.2 and a median age at biopsy of 63 years. Compared with patients with renal AL, those with renal AH/AHL had less frequent concurrent cardiac involvement, higher likelihood of having circulating complete monoclonal immunoglobulin, lower sensitivity of fat pad biopsy and bone marrow biopsy for detecting amyloid, higher incidence of hematuria, and better patient survival. The hematological response to chemotherapy was comparable with renal AL. In 42% of patients, AH/AHL could not have been diagnosed without LMD/MS. Thus, renal AH/AHL is an uncommon and underrecognized form of amyloidosis, and its diagnosis is greatly enhanced by the use of LMD/MS for amyloid typing. The accurate histological diagnosis of renal AH/AHL and distinction from AL may have important clinical and prognostic implications.
authors.affiliation: Department of Laboratory Medicine and Pathology, Mayo Clinic, Division of Anatomic Pathology, Hilton 10-20 200 First Street, SW, Rochester, Minnesota 55905, USA. nasr.samih@mayo.edu
authors.forename: Samih H
authors.initials: SH
authors.lastname: Nasr
authors.forename: Samar M
authors.initials: SM
authors.lastname: Said
authors.forename: Anthony M
authors.initials: AM
authors.lastname: Valeri
authors.forename: Sanjeev
authors.initials: S
authors.lastname: Sethi
authors.forename: Mary E
authors.initials: ME
authors.lastname: Fidler
authors.forename: Lynn D
authors.initials: LD
authors.lastname: Cornell
authors.forename: Morie A
authors.initials: MA
authors.lastname: Gertz
authors.forename: Angela
authors.initials: A
authors.lastname: Dispenzieri
authors.forename: Francis K
authors.initials: FK
authors.lastname: Buadi
authors.forename: Julie A
authors.initials: JA
authors.lastname: Vrana
authors.forename: Jason D
authors.initials: JD
authors.lastname: Theis
authors.forename: Ahmet
authors.initials: A
authors.lastname: Dogan
authors.forename: Nelson
authors.initials: N
authors.lastname: Leung
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000686:Amyloidosis / Q000175:diagnosis* / Q000276:immunology / Q000401:mortality / Q000473:pathology; D005260:Female; D005455:Fluorescent Antibody Technique; D006801:Humans; D007143:Immunoglobulin Heavy Chains / Q000032:analysis*; D007147:Immunoglobulin Light Chains / Q000032:analysis*; D007674:Kidney Diseases / Q000175:diagnosis* / Q000276:immunology / Q000401:mortality / Q000473:pathology; D061346:Laser Capture Microdissection; D008297:Male; D013058:Mass Spectrometry; D008875:Middle Aged
chemical_list: D007143:Immunoglobulin Heavy Chains; D007147:Immunoglobulin Light Chains