Objective: Fungal extracts added to conventional treatment for Leishmania infantum determine the disappearance of Leishmania DNA in fungi-treated dogs. The aim of the present study was to monitor the Leishmania load in blood tissue from naturally infected dogs before and after anti-leishmanial therapy associated with fungal extracts.

Materials and Methods: A cohort of dogs naturally infected with Leishmania infantum were divided into two groups: the control group treated with meglumine stibiate and allopurinol, and the study group who were additionally treated with a mix of fungal extracts (Shiitake 125 mg, Reishi 62.5 mg, Cordyceps 62.5 mg, at the dosage of 34 mg of the extract mixture per kilogram of body weight). We then monitored the parasite presence and blood parameters at different time points.

Results: Polymerase Chain Reaction (PCR) analysis revealed that Leishmania infantum DNA present at the beginning of the study was no longer detectable for all the fungi-treated dogs, and cytohistological analyses confirmed the absence of Leishmania amastigotes in fungi-treated dogs.

Conclusions: The combination of allopurinol, meglumine stibiate, and fungal extracts demonstrates a negative bone marrow PCR and clear bone marrow smears, a result that persists for over a year. These promising results motivate further exploration of fungal extracts as cost-effective and low-toxicity adjuncts in anti-Leishmania treatment strategies.