Persistent cobalamin deficiency causing failure to thrive in a juvenile beagle

Abstract

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 hereditary metabolic disorders were considered. Laboratory test results of low serum cobalamin (Cbl) concentrations, anaemia, leucopenia and methylmalonic aciduria while the dog was receiving a balanced commercial canine diet were suggestive of a congenital selective Cbl malabsorption. Treatment with repeated injections of parenteral cyanocobalamin (CN-Cbl) at 50 microg/kg every two weeks corrected the Cbl-deficient state and reversed all the clinical abnormalities. Selective Cbl malabsorption has previously been described in giant schnauzers and border collies and represents a unique readily treatable hereditary metabolic disorder.

Degenerative Liver Disease in Young Beagles with Hereditary Cobalamin Malabsorption Because of a Mutation in the Cubilin Gene

“…These are typical findings described in children with congenital cobalamin deficiency 2, 14. Neutropenia was also reported in the only previously published case of a cobalamin‐deficient Beagle 4. Because cubilin is required for renal tubular reabsorption of some proteins, persistent proteinuria is also a typical finding in children with IGS15 and was detected in 1 dog in this report.…”

“…Because similar clinical signs were described previously in a cobalamin‐deficient Beagle,4 serum was submitted for cobalamin and folate concentrations, identifying a cobalamin concentration below the measurement limit (<150 ng/L; RI, 261–1,001 ng/L). The subsequent finding of marked methylmalonic aciduria (5,460 mmol/mol creatinine; RI, <2 mmol/mol) and hyperhomocysteinemia (69.9 μmol/L; RI, 4.3–18.4 μmol/L) was supportive of a cobalamin‐depleted state 7.…”

“…This is a rare autosomal recessive disorder which, if left untreated, results in failure to thrive, megaloblastic anemia, proteinuria, and neurological damage 2. In dogs, primary cobalamin malabsorption, which is analogous to IGS in humans, has been reported in young Australian Shepherds,3 a Beagle,4 Border Collies,5, 6, 7 and Giant Schnauzers 8. The genetic defects in affected Border Collies and Beagles recently have been identified as 2 independent mutations in the CUBN gene 9, 10.…”

“…The genetic defects in affected Border Collies and Beagles recently have been identified as 2 independent mutations in the CUBN gene 9, 10. Similar to human patients, dogs typically present at a young age with inappetence, weakness, and failure to thrive 4, 5, 6, 8, 11. Although liver disease is recognized in cobalamin‐deficient farm animals, especially lambs,12, 13 it has not been reported in dogs suffering from hereditary cobalamin malabsorption.…”

Inherited metabolic disease in companion animals: Searching for nature’s mistakes

“…This result is indicative of cobalamin malabsorption syndrome and serum cobalamin levels were decreased. As previously reported by Fordyce et al (2000), this patient was successfully treated by parenteral vitamin B12 administration every 2-4 weeks. Cobalamin malabsorption has also been described in giant Schnauzers (Fyfe et al, 1991), Border collies (Battersby et al, 2005), and Australian shepherd dogs (He et al, 2005).…”