Acute-phase proteins in dogs naturally infected with Leishmania infantum during and after long-term therapy with allopurinol

Acute Phase Proteins (APP) are a group of serum proteins synthesized by the liver, which increase during inflammation (Eckersall 2000; Murata et al., 2004). In human visceral leishmaniasis high concentrations of some APP have been reported (Wasunna et al., 1995; Singh et al., 1999). Their concentrations decreased to normal values during therapy thus, they have been proposed as non-invasive markers to monitor the disease, response to therapy and relapses (Wasunna et al., 1995). High concentrations of Haptoglobin (Hp), C-Reactive Protein (CRP) and Ceruloplasmin (CP) have been reported in a previous study for canine leishmaniasis (CanL), suggesting that the protozoan induces an acute phase response in the host (Martinez-Subiela et al., 2002). During short-term treatment for CanL the concentration of CRP and CP decreased significantly when compared to the high initial values, indicating that these proteins could be useful to evaluate the initial response to treatment (Martinez-Subiela et al., 2003). The aim of this study was to monitor changes in serum concentration of CRP, Hp and SAA in dogs naturally infected by Leishmania infantum during a long-term treatment with allopurinol, in order to determine their potential usefulness for withdrawing treatment and revealing relapses during follow-up post treatment.