Serum cardiac troponin I concentrations in dogs with leishmaniasis: correlation with age and clinicopathologic abnormalities

Abstract

Background: There is anecdotal evidence of myocardial injury in dogs with leishmaniasis due to generalized vasculitis and myocarditis.

Objective: The aims of this study were to evaluate serum concentration of cardiac troponin I (cTnI) as an indicator of myocardial injury in dogs with leishmaniasis and to assess the relationship between cTnI concentration and age, serum antibody titer, and a variety of blood analytes.

Methods: In this retrospective study, serum cTnI concentration was measured in dogs with leishmaniasis and in age-matched healthy dogs. Diagnosis was based on clinical signs and moderate-to-high seropositivity for Leishmania as measured by ELISA. Correlations between cTnI concentration and ELISA seropositivity, PCV, concentrations of serum creatinine, total protein, albumin, and globulin, albumin:globulin ratio (A/G), and urine protein:creatinine ratio (UPC) were investigated. The Mann-Whitney test was used to compare analytes between dogs with normal and increased (> 0.06 μg/L) cTnI concentration and to compare cTnI concentrations between dogs with and without anemia, azotemia, and proteinuria.

Results: In dogs with leishmaniasis (n = 40), median cTnI concentration was higher than in control dogs (n = 11) (P = .011). Sixteen dogs (40%) with leishmaniasis had increased cTnI concentration; cTnI was moderately to weakly correlated with decreased albumin concentration, decreased A/G, increased UPC, decreased PCV, positive Leishmania titer, and increased age. Dogs with leishmaniasis had significantly higher total protein and globulin concentrations and lower PCV, albumin concentration, and A/G than control dogs. Hematologic and biochemical analytes did not differ significantly between dogs with cTnI concentration within the reference interval and those with increased concentrations. Concentration of cTnI was higher in proteinuric dogs compared with nonproteinuric dogs (P = .017).

Conclusion: A proportion of dogs with leishmaniasis have increased serum cTnI concentration, indicative of some degree of cardiac injury. Additional studies are needed to investigate the relationship between leishmaniasis and possible myocardial injury.