Magnetic resonance cholangiopancreatography uncovering massive gallbladder mucocele in a patient with ambiguous clinical and laboratory findings: A case report

Acquired dysfunction of CFTR underlies cystic fibrosis-like disease of the canine gallbladder

Mucocele formation in dogs is a unique and enigmatic muco-obstructive disease of the gallbladder caused by the amassment of abnormal mucus that bears striking pathological similarity to cystic fibrosis. We investigated the role of cystic fibrosis transmembrane conductance regulatory protein (CFTR) in the pathogenesis of this disease. The location and frequency of disease-associated variants in the coding region of CFTR were compared using whole genome sequence data from 2,642 dogs representing breeds at low-risk, high-risk, or with confirmed disease. Expression, localization, and ion transport activity of CFTR were quantified in control and mucocele gallbladders by NanoString, Western blotting, immunofluorescence imaging, and studies in Ussing chambers. Our results establish a significant loss of CFTR-dependent anion secretion by mucocele gallbladder mucosa. A significantly lower quantity of CFTR protein was demonstrated relative to E-cadherin in mucocele compared with control gallbladder mucosa. Immunofluorescence identified CFTR along the apical membrane of epithelial cells in control gallbladders but not in mucocele gallbladder epithelium. Decreases in mRNA copy number for CFTR were accompanied by decreases in mRNA for the Cl-/[Formula: see text] exchanger SLC26A3, K+ channels (KCNQ1, KCNN4), and vasoactive intestinal polypeptide receptor (VIPR1), which suggest a driving force for change in secretory function of gallbladder epithelial cells in the pathogenesis of mucocele formation. There were no significant differences in CFTR gene variant frequency, type, or predicted impact comparing low-risk, high-risk, and definitively diagnosed groups of dogs. This study describes a unique, naturally occurring muco-obstructive disease of the canine gallbladder, with uncanny similarity to cystic fibrosis, and driven by the underlying failure of CFTR function.NEW & NOTEWORTHY Cystic fibrosis transmembrane conductance regulatory protein (CFTR) genomic variants and expression of mRNA, protein, and electrogenic anion secretory activity of CFTR were characterized in dog gallbladder. Acquired inhibition of CFTR expression by gallbladder epithelium was identified as underpinning a naturally occurring muco-obstructive disease of the dog gallbladder that bears striking pathological similarity to animal models of cystic fibrosis.

A Rare Case of Calculous Gallbladder Hydrops Presenting With Atypical Abdominal and Urinary Symptoms

Gallbladder hydrops, otherwise known as gallbladder mucocele, is an uncommon gallbladder condition characterised by gallbladder distention and accumulation of clear mucous-like inspissated bile. Patients with gallbladder hydrops are usually asymptomatic and incidentally diagnosed on cross-sectional imaging or diagnostic laparoscopy. This case report presents a rare case of calculous gallbladder hydrops measuring 217mm in maximal length in a 56-year-old female presenting with atypical abdominal and urinary symptoms. The radiological and intraoperative images will also be presented to highlight the extensiveness of the disease and therefore the importance of considering gallbladder hydrops as a differential in these patients.