Mycological and Serological Study of Fungal Sinusitis among Sudanese Patients

Abstract

Fungal sinusitis is increasingly recognized, both in normal and immunocompromised individuals. Fungal sinusitis, if not diagnosed early and treated promptly, can cause severe complications, which in some patients could be fatal, hence early laboratory diagnosis is very important to prevent recurrences and complications. The objectives of this study is to determine the fungi causing nasal and paranasal infections in Sudanese patients. In this study 488 specimens (244 nasal biopsies and 244 blood) were collected. The 244 nasal biopsies were examined directly using 20% KOH and cultured on Sabouraud’s dextrose agar for primary isolation. Counterimmuno-electrophoresis (CIE) was done for the 244 patients’ sera. Eighteen of A. flavus isolates were tested for aflatoxin production by thin layer chromatography (TLC). One hundred and seven specimens (43.1%) gave fungal hyphae in direct microscopy and yielded fungal growth. Eighty nine of them (83.3%) grew A.flavus, 6 (5.6%) grew A. terreus, 6 (5.6%) grew Bipolaris sp.. One (0.9%) yielded Curvularia lunata, 1 (0.9%) yielded A.nidulans, 1 (0.9%) grew black yeast and 1 (0.9%) grew Conidiobolus coronatus (Zygomycetes), but 2(1.9%) Dematiaceous cultures were unidentified. Seventy nine (73.8%) patients’ sera of the positive cultures gave precipitin lines in the CIE. This indicated the correlation between isolates and their serological testing. Eighteen of A. flavus isolates were tested for aflatoxin production by thin layer chromatography (TLC), 17 of them (94.4 %) were positive; this high percentage of aflatoxin detection indicates their possible role in the pathogenicity of this microorganism. In conclusion the combination of biopsies, for direct microscopy, fungal growth and identification and serology is of great importance for good diagnosis.