Urine 5-hydroxyindoleacetic acid in Cavalier King Charles spaniels with preclinical myxomatous mitral valve disease

Christiansen, L. B.; Cremer, S. E.; Helander, A.; Madsena, Tine; Reimann, M. J.; Moller, J. E.; Hoglund, K.; Ljungvall, I; Haggstrom, J.; Olsen, L. H.

doi:10.1016/j.tvjl.2019.06.005

Research article - Peer-reviewed, 2019

Urine 5-hydroxyindoleacetic acid in Cavalier King Charles spaniels with preclinical myxomatous mitral valve disease

Christiansen, L. B.; Cremer, S. E.; Helander, A.; Madsena, Tine; Reimann, M. J.; Moller, J. E.; Hoglund, K.; Ljungvall, I; Haggstrom, J.; Olsen, L. H.

Abstract

Higher concentrations of circulating serotonin have been reported in Cavalier King Charles spaniels (CKCS) compared to other dog breeds. The CKCS is also a breed highly predisposed to myxomatous mitral valve disease (MMVD). The aim of this study was to determine urine concentrations of 5-hydroxyindoleacetic acid (5-HIAA), the major metabolite and excretion product of serotonin, in a population of CKCS with preclinical MMVD, and to evaluate whether urine 5-HIAA concentrations were associated with MMVD severity, dog characteristics, setting for urine sampling, platelet count, and serotonin concentration in serum and platelet-poor plasma (PPP). The study population consisted of 40 privately-owned CKCS (23 females; 17 males) with and without preclinical MMVD as follows: American College of Veterinary Internal Medicine (ACVIM) group A (n =11), ACVIM group B1 (n = 21) and ACVIM group B2 (n = 8).Urine 5-HIAA concentrations were not significantly associated with preclinical MMVD disease, platelet count or circulating concentrations of serotonin (in serum and PPP; P> 0.05). Females had higher 5-HIAA concentrations than males in morning urine collected at home (females, 3.1 [2.9-3.7] mu mol/mmol creatinine [median and quartiles]; males, 1.7 [1.2-2.2] creatinine; P= 0.0002) and urine collected at the clinic (females, 3.5 [3.1-3.9] mu mol/mmol creatinine; males, 1.6 [1.3-2.1] mu mol/mmol creatinine; P < 0.0001). Five-HIAA concentrations in urine collected at home and at the clinic were significantly associated (P= 0.0004; r= 0.73), and higher concentrations were found in urine collected at the clinic (P= 0.013). Urine 5-HIAA concentration was influenced by sex and setting of urine sampling. Urine 5-HIAA concentration was not associated with MMVD severity or circulating concentrations of serotonin in CKCS with preclinical disease. (C) 2019 Elsevier Ltd. All rights reserved.