Gallbladder Mucocele Formation is Associated with Urinary Protein Loss

The canine gallbladder sits between liver lobes in the abdomen and serves as a reservoir for bile, an important liquid that aids in fat digestion. When the gallbladder lining secretes abnormally thick mucus that accumulates and becomes sludge-like, a gallbladder mucocele (GBM) forms. Gallbladder mucoceles prevent the normal flow of bile from the gallbladder into the small intestine and can lead to gallbladder rupture. Shetland Sheepdogs, Miniature Schnauzers, and Cocker Spaniels are predisposed to this condition, but it can also be seen in other breeds and mixed breed dogs. AKC Canine Health Foundation (CHF) funded investigators have explored the metabolic problems that lead to GBM formation to inform better diagnostic tests and prevention strategies.

Investigators previously noted abnormalities in amino acids, glutathione, RNA, adenosine, bile acids, cholesterol, lipids, and energy associated with GBM formation - providing clues about the metabolic pathways and compounds that ultimately affect the gallbladder lining. They also documented that dogs with gallbladder mucocele are likely to have alterations in their serum thyroid hormone concentrations, even though they lack clinical signs of hypothyroidism. (See Researching the Cause of Gallbladder Mucocele in Dogs.) Since GBM formation is associated with metabolic conditions such as Cushing’s Disease (hyperadrenocorticism), hyperlipidemia, and pancreatitis, and each of these diseases is associated with protein loss in the urine, investigators examined the possibility of a direct relationship between GBM formation and proteinuria.

By reviewing the medical records of 25 dogs with GBM representing 15 different breeds and comparing them to similar healthy dogs (case controls), investigators found that urine protein loss was significantly higher in dogs with GBM.¹ Dogs with greater urine protein loss also had more severe clinical signs as measured by an illness severity score. While this study does not prove that GBM formation causes proteinuria or vice versa, it does document an important association that warrants further investigation in clinical and research settings.

Additional study is needed for a deeper understanding of the metabolic factors that contribute to GBM formation and associated conditions. CHF and its donors will continue to invest in research exploring the interactions of fat metabolism, hormone production, blood pressure, and more on gallbladder and kidney function so that dogs at risk of disease can be identified early and preventive measures initiated to prevent gallbladder rupture. For now, veterinarians have data indicating that dogs with GBM should be evaluated for proteinuria. Learn more about CHF’s diverse research portfolio at akcchf.org/research.

1. Lindaberry, C., Vaden, S., Aicher, K. M., Seiler, G., Robertson, J., Cianciolo, R., Yang, C., & Gookin, J. L. (2021). Proteinuria in dogs with gallbladder mucocele formation: A retrospective case control study. Journal of Veterinary Internal Medicine. https://doi.org/10.1111/jvim.16051