Introduction.Paracoccidioidomycosis (PCM) is a systemic disease caused by thermodymorphic fungi of the Paracoccidioidesbrasiliensis complex - P. brasiliensis and P. lutzii. Patients with PCM reveal specific cellular immune impairment. Despite the effective treatment, quiescent fungi can lead to relapse, usually late, whose serological diagnosis has been deficient. Objective.The present study was carried out with the objective of investigating a biomarker for the identification of PCM relapse and another molecule that behaves as an immunological recovery biomarker and, therefore, can be used as a cure criterion. Patients and Methods.Proteomic analysis was performed in serum from nine patients from the Botucatu region, with PCM caused by P. brasiliensis, five of them had presented a late relapse. The evaluations were performed in three different moments: pre-treatment, at relapse and post-treatment of relapse, four who did not present relapse, evaluated in two different moments: before and after treatment and from 3 healthy controls. The proteomic approach was performed in four steps - protein quantification, protein digestion in solution, peptide sequencing by mass spectrometry and data analysis for protein identification.Results. In the follow-up evaluation of the proteins identified in PCM patients infected by P. brasiliensis, compared regarding the presence of relapse, the same 22 proteins were identified. Using transferrin and haptoglobin as the main binding protein, strong interactions were observed with all the other proteins.  Patient follow-up suggests that cerulosplamin may be a marker of relapse and that transferrin and apolipoprotein A-II may contribute to the evaluation of cure and discontinuation of treatment, avoiding that this decision is too early.Conclusion. The proteomic methodology provided the selection of one protein to predict a relapse and two proteins to be a biomarker of cure. The evaluation of these proteins in a higher number of patients should be carried out in order to validate these findings.

Ceruloplasmin, transferrin and apolipoprotein A-IIplay important hole in treatment’s follow-up of paracoccidioidomycosis patients.