Influence of domperidone supplementation on short-term changes in C-reactive protein and paraoxonase-1 in dogs with leishmaniasis undergoing meglumine antimoniate and allopurinol therapy

Background: C-reactive protein (CRP) and paraoxonase 1 (PON1) might increase and decrease in canine leishmaniasis (CanL), and both can rapidly normalize after therapy. Recently, supplementation of domperidone with conventional therapy, increasing the activity of cells involved in acute phase responses in vitro. This combined therapy has been recommended to treat mild forms of CanL; however, no studies have investigated the effects of domperidone supplementation on early CRP or PON1 changes in dogs with CanL. Objectives: The aim of this study was to evaluate whether domperidone, added to conventional treatments, modifies CRP concentration and PON1 activity kinetics in CanL dogs responsive to conventional therapy. Methods: Serum CRP concentrations and PON1 activities were measured in dogs with mild CanL before (t-0) and 3 (t-1), 7 (t-2), 14 (t-3), and 21 (t-4) days after treatment with N-methylglucamine antimoniate and allopurinol alone (n = 18) or combined with domperidone (n = 18). Results: C-reactive protein concentrations increased at t-1 in the domperidone group, especially when the CRP concentration at t-0 was normal. However, the concentrations normalized at t-4 in 18/18 dogs compared with 14/18 dogs not receiving domperidone. The median PON1 activity decreased at t-1 in the domperidone group, and this decrease was more significant in dogs with normal PON1 activity at t-0. Conclusions: Based on these results, transient increases in CRP concentrations or decreases in PON1 activities after domperidone administration should not be erroneously interpreted as signs of a worsening disease process.