COMPARISON BETWEEN DD, ELISA AND IFA FOR DETECTING ASPERGILLUS ANTIBODIES IN PATIENTS WITH POLYPOID CHRONIC RHINOSINUSITIS

S. Oliveri1*, L. Trovato1, C. Grillo2, A. Serra2

Author address: 

1Department of Microbiological Science University of Catania 2Department of Otorhinolaryngology, University of Catania

Abstract: 

Purpose: The aim of this study was the comparison of indirect fluorescent antibody (IFA), ELISA and double diffusion in agarose gel (DD) for detecting the antibody response to Aspergillus in a pool of sera from patients undergoing surgery for polypoid chronic rhinosinusitis. Methods: Were analyzed 36 sera from patients undergoing surgery for polypoid chronic rhinosinusitis at the Otolaryngology Unit of the Policlinico G. Rodolico Catania. The slides with hyphae of A. flavus 136 M and A. fumigatus NCPF 3272, for the detection of antibodies in IFA, were prepared. All sera were first adsorbed with conidia of Penicillium lanosum Westling, to limit the crossing responses. DRG Diagnostics Kit was used for the detection of the A. fumigatus antibodies in ELISA. Finally for DD were used antigens of A. fumigatus (met), A. fumigatus (som), A. flavus, A. nidulans, A. niger, and A. terreus. During the surgery a sample of fluids and fresh tissue were taken for standard mycological investigation. Part of the fluids and fresh tissue material was ground up in 10% KOH and Parker ink (blueblack) and then observed under a light microscope. Samples were cultured on Sabouraud glucose agar and incubated at 30°C. Results: Four (11%) of 36 patients showed the presence of narrow septate hyphae with acute angle branching by direct microscopic examination. In three of these four, A. flavus was be isolated. In the other sample A. fumigatus was isolated. Related to the serological data, all sera were negative for the detection of precipitating anti-Aspergillus antibodies. The 42% of the sera was positive in IgG ELISA test. The 92% of the sera was positive in IgG IFA against A. fumigatus, while the 83% against A. flavus. The agreement between IFA-fumigatus, IFA-flavus and ELISA assay was 52%. In the patients not colonized by Aspergillus, the IFA antibody titers ranged from 20 to 160. In the four patients colonized with Aspergillus the IFA titers ranged from 320 to 1280. Conclusions: To discriminate patients with nasal polyps colonized with Aspergillus, detection of antibodies by IFA was better than ELISA.
2010

abstract No: 

166

Full conference title: 

4th Advances Against Aspergillosis
    • AAA 4th (2010)