Levels of IgM and IgA Circulating Immune Complexes in Dogs with Leishmaniasis

Summary The concentrations of IgM and IgA circulating immune complexes (CIC) were determined in 82 dogs with naturally acquired leishmania infection and in a control group of 25 healthy dogs. The mean serum IgM and IgA CIC concentration in infected dogs were significantly (IgM; P < 0.004; IgA; P < 0.000) higher than in the control group. An increase in IgM and IgA CIC concentration was found in 47.6 and 95.1 %, respectively, of the leishmania-infected dogs. The serum IgM and IgA CIC concentrations in infected dogs showing hypercreatininaemia were not statistically higher than those of sick dogs with normal creatininaemia. When hypercreatininaemia (≥ 1.30 mg/dl) was used as an indicator for CIC disease, the positive predictive value obtained was 0.368 for IgM CIC and 0.894 for IgA CIC, indicating that renal function impairment was associated with the high serum IgM and IgA CIC concentrations in 36.8 and 89.4 %, respectively, of the infected dogs.