Background: Spirocerca lupi is a nematode of canids that forms a nodule in the esophagus that can undergo neoplastic transformation. C-reactive protein (CRP) is a major acute phase protein in the dog that has been used for treatment, monitoring, and prognostication in inflammatory and neoplastic disease.
Hypothesis/Objectives: The objectives of this study were to determine if serum CRP concentration (1) is increased in canine spirocercosis, (2) can be used to determine neoplastic transformation, and (3) can be used to monitor response to treatment in benign spirocercosis.
Animals: Forty-two dogs naturally infected with S. lupi and 21 control dogs.
Methods: A retrospective study was performed. The infected cases were divided into benign (n = 28) or malignant (n = 14) spirocercosis. CRP was performed on all of the spirocercosis and control cases at presentation. Statistical analysis was done by the one-way analysis of variance and Student's t-test.
Results: The mean CRP concentration in the benign cases was 60.4 ± 48.0 mg/L and that of the malignant cases was 76.5 ± 44.8 mg/L; both values were significantly higher (P < .001) than those of the control group where the mean was 13.4 ± 17.9 mg/L. The mean CRP concentration for the convalescent sera in the benign group was lower than the pretreatment concentrations (P= .01).
Conclusion and Clinical Importance: CRP cannot be used to differentiate between benign and malignant spirocercosis. There is a decrease in CRP concentration in dogs with benign spirocercosis once treatment has commenced. Serial CRP measurement can be used to monitor response to treatment in benign spirocercosis.