Serum 25-hydroxyvitamin D concentrations in dogs with gallbladder mucocele

Abstract

Gallbladder mucocele (GBM) is a common biliary disorder in dogs. Gallbladder hypokinesia has been proposed to contribute to its formation and progression. The specific cause of gallbladder stasis in dogs with GBM as well as viable treatment options to resolve dysmotility remains unknown. Vitamin D deficiency is one of the many potential causes of gallbladder hypokinesia in humans and repletion results in complete resolution of stasis. Improving our understanding of the relationship between serum vitamin D and GBM could help identify dogs as a model for humans with gallbladder hypokinesia. Furthermore, this relationship could provide insight into the pathogenesis of GBM and support the need for future studies to investigate vitamin D as a novel treatment target. Therefore, goals of this study were i) to determine if serum 25-hydroxyvitamin(OH)D concentrations were decreased in dogs with GBM, ii) if serum 25(OH)D concentrations were different in clinical versus dogs subclinical for GBM, and iii) to determine if serum 25(OH)D concentrations could predict the ultrasonographic type of GBM. Sixty-two dogs (clinical, n = 26; subclinical, n = 36) with GBM and 20 healthy control dogs were included in this prospective observational study. Serum 25(OH)D concentrations were measured with a competitive chemiluminescence immunoassay. Overall, dogs with GBM had lower serum 25(OH)D concentrations than control dogs (P = 0.004). Subsequent subgroup analysis indicated that this difference was only significant in the subclinical group compared to the control dogs (P = 0.008), and serum 25(OH)D concentrations did not significantly differ between dogs clinical for GBM versus subclinical or control dogs, indicating that inflammatory state in clinical dogs was not the major constituent of the observed findings. Decreasing serum 25(OH)D concentrations, but not clinical status, was associated with a more advanced developmental stage of GBM type determined by ultrasonography. Our results indicate that vitamin D has a role in dogs with GBM. Additional studies are needed to assess if reduced vitamin D in dogs with GBM is a cause or effect of their biliary disease and to investigate if vitamin D supplementation could be beneficial for dogs with GBM.

Ultrasonographic patterns, clinical findings, and prognostic variables in dogs from Asia with gallbladder mucocele

“…Moreover, the majority of each cohort consisted predominately of dogs with less advanced GBM (ie, types I‐III; 65%‐69%). 7 , 13 A specific explanation for the link between ultrasonographic biliary pattern and clinical status was not established in this study. The amount and organization/consolidation of intraluminal inspissated material generally increases with developmental stage of GBM.…”

“… 6 , 18 Two previous studies found no association between GBM type and clinical status. 7 , 13 One potential explanation for the lack of association in the previously mentioned studies is that statistical comparisons were not sufficiently powered (ie, type II error). Each of the aforementioned studies only included 43 and 62 dogs, respectively, which were then allocated into even smaller groups based on GBM type and clinical status.…”

“… 1 , 2 , 3 , 4 Surgical intervention to remove the gallbladder has an approximate in‐hospital death rate of 20% (range, 7%‐31%). 2 , 5 , 6 , 7 , 8 The specific disease etiology of GBM remains unknown; however, affected dogs have a high incidence of concurrent endocrinopathies and hyperlipidemia. 9 , 10 Further, the disease is over‐represented in purebred dogs such as Shetland sheepdog, border terrier, miniature schnauzer, and beagles.…”

“…Gallbladder rupture is a relatively common complication of GBM occurring in approximately 25% (range, 19%‐38%) of dogs with signs of biliary tract disease. 2 , 5 , 7 , 8 , 15 There are conflicting reports regarding the clinical importance of gallbladder rupture in dogs with GBM. A recent large, retrospective study found that the presence of gallbladder rupture in dogs with GBM that had a cholecystectomy was associated with in‐hospital death.…”

“…Gallbladder rupture is a relatively common complication of GBM occurring in approximately 25% (range, 19%‐38%) of dogs with signs of biliary tract disease 2,5,7,8,15 . There are conflicting reports regarding the clinical importance of gallbladder rupture in dogs with GBM.…”