Use of immunoblotting assay improves the sensitivity of paracoccidioidomycosis diagnosis

The purpose of this work was to evaluate two serological assays: double immunodiffusion (DI) and immunoblotting (IB) in immunodiagnosis of paracoccidioidomycosis (PCM). We evaluated by IB assay 23 sera samples from patients with clinical confirmation of PCM, all of them with negative DI results agai...

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Bibliographic Details
Published in:Journal of Venomous Animals and Toxins including Tropical Diseases
Main Authors: D. F. Silva, C. M. Assis, I. M. Zamboni, L. C. Barreto, V. S. Kohara, A. P. Vicentini-Moreira
Format: Article in Journal/Newspaper
Language:English
Published: SciELO 2008
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Online Access:https://doi.org/10.1590/S1678-91992008000200009
https://doaj.org/article/8dc77bdddf0840e78b54e274073b1ea2
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Summary:The purpose of this work was to evaluate two serological assays: double immunodiffusion (DI) and immunoblotting (IB) in immunodiagnosis of paracoccidioidomycosis (PCM). We evaluated by IB assay 23 sera samples from patients with clinical confirmation of PCM, all of them with negative DI results against culture filtrate from Paracoccidioides brasiliensis isolate 113. For IB, as well as for comparative DI assay, we employed soluble components of the cell wall outer surface (SCCWOS) from P. brasiliensis isolate 113 cultivated at 36°C in Fava-Neto's agar medium for 5 and 10 days. Among the 20 sera samples analyzed by DI, 13 (65%) were negative and 7 (35%) were positive against SCCWOS obtained on the 5th and 10th days. By IB assay, 95.4% and 100% of sera reacted against gp43 and gp70 present in SCCWOS from the 5th day and 95.6% recognized these fractions when evaluated against SCCWOS from the 10th day. Our results demonstrated that the use of an immunoenzymatic assay significantly improves the sensitivity of PCM immunodiagnosis and also suggests that at least two serological tests for antibody detection should be adopted in cases of questionable diagnosis.