Fucosidosis in an English Springer Spaniel presenting as a malabsorption syndrome

A case of alpha-fucosidosis in a 2-year-old male English Springer Spaniel presented as a malabsorption syndrome without any clinical neurological abnormalities. The dog had a history of chronic weight loss, diarrhoea, mild anaemia, hypoproteinemia and reduced jejunal absorption of D-xylose. A diagnosis of fucosidosis with intestinal malabsorption was based on these findings, markedly reduced plasma fucosidase levels and the diffuse infiltration of the lamina propria and submucosa of the stomach, small intestine, Peyer's patches and mesenteric lymph nodes by macrophages with finely vacuolated cytoplasm. Cytoplasmic vacuolation was also a feature of cells of the pancreas, thryroid, parathyroid and adenohypophysis and the epithelia lining respiratory airways and the urogenital tract. Neurons of the autonomic plexuses of the gastrointestinal tract and the urinary bladder as well as those of the brain, spinal cord, spinal ganglia and retina were also vacuolated. The profound decrease in sigma-fucosidase activity in the brain, liver and kidney was accompanied by a marked increase in 6 other lysosomal enzymes, especially beta-n-acetyl glucosaminidase.