Rhinosporidiosis: experience with sixteen cases

ABSTRACT

Rhinosporidiosis is a chronic granulomatous disease primarily of the anterior nares. It is histologically characterized by mucosal lymphoplasmacellular infiltrates, transepithelial elimination of nodular bodies [NB] and destruction of late stage NBs in histiocytic granulomata with central neutrophilic microabscesses. Early NBs are immunohistochemically positive for alpha 1-AT alpha 1-ACT, CEA, S100, fibronectin, amyloid-p-component, IgG, IgA, Clq and C3. Structures formerly regarded as "sporangia" [NB] and "spores" are believed to be lysosomal bodies loaded with indigestible residues to be cleared via transepithelial elimination. This is supported by immunohistochemical findings and ultrastructural demonstration of lysosomal bodies in early NBs but not in end-stage NBs which contain mostly amorphous electron dense materials. Immunopathology of the disease is discussed and in view of overwhelming evidence against a fungal etiology it is proposed to change the name to Seeber's disease