title: Histiocytes containing immunoglobulin crystals in the urine of a patient with IgA kappa plasmacytoma of the bladder.
abstract: Exfoliative cytology specimens from patients with plasma cell dyscrasias are rarely diagnostic, though there are reports of neoplastic plasma cells observed in pleural fluid and urine. Immunoglobulin concretions or crystals associated with neoplastic plasma cell populations have been well described. These crystals may be found within plasma cell nuclei or cytoplasm, extracellularly, or within cells of histiocytic lineage where they are presumably derived by phagocytosis. To the best of our knowledge, this is the first report of immunoglobulin crystals within histiocytes in the urine of a patient with plasmacytoma. A 61-year-old male underwent routine cystoscopy and urine collection to evaluate hematuria. The bladder biopsy demonstrated IgA kappa-producing plasmacytoma. Urine cytopsin preparations did not contain plasma cells, but there were histiocytic cells with degenerative nuclei and eccentrically located cytoplasmic spherical refractile hyaline crystals thought to be immunoglobulin crystals. This was supported by immunocytochemical staining.
authors.affiliation: Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota 55905, USA.
authors.forename: Dylan V
authors.initials: DV
authors.lastname: Miller
authors.forename: Rebecca F
authors.initials: RF
authors.lastname: McClure
authors.forename: Barbara G
authors.initials: BG
authors.lastname: Crawford
authors.forename: Steven R
authors.initials: SR
authors.lastname: Zeldenrust
authors.forename: Bradley C
authors.initials: BC
authors.lastname: Leibovich
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Sebo
mesh_terms: D003460:Crystallization; D003558:Cystoscopy; D006644:Histiocytes / Q000473:pathology*; D006801:Humans; D007070:Immunoglobulin A; D007145:Immunoglobulin kappa-Chains; D007136:Immunoglobulins; D007150:Immunohistochemistry; D002479:Inclusion Bodies / Q000276:immunology / Q000648:ultrastructure; D008297:Male; D008875:Middle Aged; D010954:Plasmacytoma / Q000175:diagnosis* / Q000652:urine*; D001749:Urinary Bladder Neoplasms / Q000175:diagnosis* / Q000652:urine*
chemical_list: D007070:Immunoglobulin A; D007145:Immunoglobulin kappa-Chains; D007136:Immunoglobulins