Agarose gel immunodiffusion tests with the addition of PEG (polyethylene glycol 6000) for the diagnosis and serological follow up of paracoccidioidomycosis infection.

By using PEG (polyethylen glycol 6000) in the gel immunodiffusion tests (ID), the precipitin lines were increased in 25.5% of the 192 sera reactions and the titers were increased from one to four serial dilutions in 44.6% of the 139 serum samples. Owing to its sensitivity, easy interpretation of the results and low cost, the use of 2% PEG incorporated into the gel in ID tests is recommended for the diagnosis and serological follow-up of paracoccidioidomycosis infections.