Frequency of abnormal C-reactive protein concentrations in blood of dogs with hypoadrenocorticism.

Abstract

BACKGROUND: C-reactive protein (CRP) concentration in serum or plasma is high in humans during adrenal crisis due to multiple mechanisms, however, the frequency and clinical relevance of high CRP concentrations in dogs with hypoadrenocorticism are unknown. HYPOTHESIS/OBJECTIVES: To determine the frequency of high CRP concentrations in serum or plasma of dogs with hypoadrenocorticism. We hypothesized that CRP concentrations are commonly above reference limit in dogs with hypoadrenocorticism with and without inflammatory comorbidities. ANIMALS: Fifty-one dogs with hypoadrenocorticism presented to 2 referral centers between 2017 and 2023. METHODS: Medical records were retrospectively reviewed for dogs diagnosed with and presenting for illness due to hypoadrenocorticism. Dogs were grouped according to identification of a concurrent inflammatory disease at the time of diagnosis, and whether electrolyte abnormalities were present. C-reactive protein concentrations were compared between groups. RESULTS: Fifty-one dogs were included. C-reactive protein concentration in serum or plasma was above 10 mg/L in 38 of 51 (75%) cases. Median CRP concentration was 52.5 mg/L (range 8-191.4); this was not significantly different between dogs with (n = 14) or without (n = 37) a known inflammatory comorbidity (54.25 [8.0-191.4] and 44.0 [8-180.8] mg/L, respectively, P = .35), or between dogs with (n = 32) or without (n = 13) electrolyte abnormalities (48.25 [8.0-180.8] and 63.0 [8.0-191.4] mg/L, respectively, P = .51). CONCLUSIONS AND CLINICAL IMPORTANCE: High CRP concentrations in serum or plasma were frequently identified in dogs with hypoadrenocorticism, including dogs without recognized inflammatory comorbidities. Hypoadrenocorticism should be considered as a differential diagnosis in cases with high CRP concentrations and vague clinical signs. Extensive investigations for high CRP concentrations in dogs with hypoadrenocorticism might not be necessary without other supporting evidence of an inflammatory comorbidity.