title: Rhinosporidiosis: immunohistochemical and electron microscopic studies.
abstract: Sixteen biopsies of rhinosporidiosis (15 nasal and one conjunctival) from 16 Southern Indian male immigrant workers showed mucosal lymphoplasmacellular infiltrates together with transepithelial elimination of nodular bodies and destruction of some late stage nodular bodies in histiocytic granulomata with central neutrophilic microabscesses. Early nodular bodies were immunohistochemically positive for alpha 1-AT, alpha 1-ACT, CEA, S100, fibronectin, amyloid-p-component, IgG, IgA, C1q and C3. Electron microscopy showed organized concentric lamellated bodies in early nodular bodies and not in end-stage nodular bodies which contained mostly amorphous electron dense materials. Structures formerly regarded as 'sporangia' and 'spores' are believed to be lysosomal bodies loaded with indigestible residues to be cleared via transepithelial elimination or segregated/destroyed by secondary immune/granulomatous responses.
authors.affiliation: Department of Pathology, Hamad General Hospital, Doha, State of Qatar.
authors.forename: B
authors.initials: B
authors.lastname: Azadeh
authors.forename: N
authors.initials: N
authors.lastname: Baghoumian
authors.forename: O T
authors.initials: OT
authors.lastname: el-Bakri
mesh_terms: D000328:Adult; D015922:Complement C1q / Q000032:analysis; D003176:Complement C3 / Q000032:analysis; D004848:Epithelium / Q000648:ultrastructure; D006801:Humans; D007070:Immunoglobulin A / Q000032:analysis; D007074:Immunoglobulin G / Q000032:analysis; D007150:Immunohistochemistry; D008247:Lysosomes / Q000648:ultrastructure; D008297:Male; D008854:Microscopy, Electron; D009297:Nasal Mucosa / Q000648:ultrastructure*; D012227:Rhinosporidiosis / Q000276:immunology / Q000473:pathology*; D000514:alpha 1-Antichymotrypsin / Q000032:analysis
chemical_list: D003176:Complement C3; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D000514:alpha 1-Antichymotrypsin; D015922:Complement C1q