Persistent cobalamin deficiency causing failure to thrive in a juvenile beagle

A six-month-old beagle was presented with a three-month history of failure to gain weight, lethargy, intermittent vomiting and seizures. Hypoglycaemia , portosystemic shunt, lead intoxication, gastrointestinal diseases and her editary metabolic disorders were considered. Laboratory test results of low serum cobalamin (Cbl) concentrations, anaemia, leucopenia and methylmaloni c aciduria while the dog was receiving a balanced commercial canine diet we re suggestive of a congenital selective Cbl malabsorption. Treatment with r epeated injections of parenteral cyanocobalamin (CN-Cbl) at 50 mu g/kg ever y two weeks corrected the Cbl-deficient state and reversed all the clinical abnormalities. Selective Cbl malabsorption has previously been described i n giant schnauzers and border collies and represents a unique readily treat able hereditary metabolic disorder.