OBJECTIVETo investigate the mechanism of fungi invasion into the mucosal tissue, and to analyse the clinical-pathological relationship.

METHODSThe clinical data of 16 patients with invasive mycosis in the nose and paranasal sinus proved by pathologic examination between Apr, 1984 and Aug, 2002 were reviewed retrospectively. There were 7 males and 9 females with an average age of 48.6 years. The pathologic morphology of fungi found in these patients was investigated. Fourteen of 16 tissue samples from the paranasal sinuses obtained by endoscopic operation were cultivated for the fungi. One sample of invasive mycosis was observed under electron-microscope.

RESULTSFourteen cases were found to have following underlying conditions, including diabetes (n = 4), malignant tumor (n = 5). The infected sites were as follows: 7 cases presenting in unilateral maxillary sinus, 6 cases involving over two nasal sinuses, 8 cases invading the orbit. Of all 16 patients, 15 were positive (93.7%) for the culture. The positive rate of aspergillus was 62.5% and mucoraceae was 25.0%. The overall mortality rate was 50.0% after investigation from 6 months to 5 years. From 16 surgical specimens, hypha were proved in all cases for histopathologic methods. All of the 16 granulomatous and crumbley materials from the paranasal sinuses were found that inflammatory responses were predominantly neutrophilic leucocytes invasion (100%), suppurative granuloma formed in 15 cases (93.7%). Invasive diseases were characterized by prominent infarcts (27.8%), angio-invasion (100%), and surprisingly, prominent optic nervous invasion (16.7%) in biopsies.

CONCLUSIONSThe incidence of invasive mycosis is correlated with patients who suffered from diabetes, malignant tumor and other basic diseases causing depression of immunological function. The pathologic study shows that the fungi which invade the tissue are mostly aspergillus or mucoraceae, and the fungal vasculitis is the direct reason for tissue damage.