Fanconi Syndrome in Irish Wolfhound Siblings.

Three juvenile male Irish wolfhound littermates presented with marked polyuria and polydipsia. The four female siblings were apparently unaffected. Diagnostic testing revealed glucosuria with normoglycemia, generalized aminoaciduria, hypokalemia and metabolic acidosis consistent with Fanconi syndrome. Renal ultrasonographic and histologic findings are presented. Cases were managed with a supplementation regimen based on a treatment protocol for Fanconi syndrome in basenjis. These dogs did not have angular limb deformities as documented previously in juvenile canine siblings with Fanconi syndrome. Fanconi syndrome has not been previously described in Irish wolfhound siblings.

Apical junction complex protein expression in the canine colon: differential expression of claudin-2 in the colonic mucosa in dogs with idiopathic colitis.

Canine idiopathic lymphocytic-plasmacytic colitis (LPC) is a well-recognized clinical and pathological entity in the dog, associated with altered immune cell populations and cytokine expression profiles. Clinical and experimental data indicate that alterations in the permeability of the intestinal epithelium contribute to the pathogenesis of a range of related conditions. The apical junction complex plays a significant role in regulating epithelial paracellular permeability, and we have characterized the distribution of a number of its component tight junction (ZO-1, occludin, claudin-2) and adherens junction (E-cadherin and beta-catenin) proteins in normal colon and colon from dogs with idiopathic LPC. ZO-1, occludin, E-cadherin, and beta-catenin exhibited a distribution in normal canine colon similar to that described previously in humans and rodents. In contrast to the situation in humans, claudin-2-specific labeling was observed in the normal canine colonic crypt epithelium, decreasing in intensity from the distal to the proximal crypt and becoming barely detectable at the luminal surface of the colon. There was little evidence for significant changes in ZO-1, occludin, E-cadherin, or beta-catenin expression in dogs affected by idiopathic LPC. However, claudin-2 expression markedly increased in the proximal crypt and luminal colonic epithelium in affected dogs, suggesting a role in the pathogenesis of canine LPC.

Evaluation of Th1, Th2 and immunosuppressive cytokine mRNA expression within the colonic mucosa of dogs with idiopathic lymphocytic-plasmacytic colitis.

The objective of this study was to evaluate the expression of the immunoregulatory and pro-inflammatory cytokines interleukin (IL)-2, IL-4, IL-6, IL-12p35, IL-12p40, interferon-gamma (IFN-gamma), and tumour necrosis factor-alpha (TNF-alpha), and the expression of the predominantly immunosuppressive cytokines transforming growth factor-beta (TGF-beta) and IL-10 in canine idiopathic lymphocytic-plasmacytic colitis (LPC). Semi-quantitative reverse transcriptase-polymerase chain reactions were performed using specific primers on RNA isolated from the colonic mucosa of healthy dogs, dogs with clinical signs of large intestinal disease but normal histopathology of the colon, and dogs with LPC. Canine LPC was associated with over-expression of IL-2 compared to healthy colonic mucosa (p<0.01) and the mucosa of dogs with large intestinal diarrhoea but normal histopathology (p<0.05). Higher levels of TNF-alpha mRNA were also seen in LPC compared to healthy mucosa (p<0.05). These results indicate that LPC is associated with activation of CD4+ T-helper lymphocytes and increased production of T-helper-1-type cytokines.