Imerslund-Gräsbeck syndrome (IGS)

The Imerslund Gräsbeck Syndrome (IGS) is an inherited disorder of vitamin B12 absorption (cobalamin malabsorption). Affected dogs are unable to absorb vitamin B12 (cobalamin) from the intestine into the bloodstream despite normal feeding. As a result, a chronic cobalamin deficiency develops, which impairs the blood-forming system and may lead to anaemia and neurological deficits. If left untreated, permanent (irreversible) damage to the brain and nervous system may occur.

Clinical signs typically appear in early puppyhood, between approximately 6 and 12 weeks of age, when the body’s cobalamin stores become depleted. Common signs include poor weight gain and growth retardation (failure to thrive), weight loss, lethargy, loss of appetite, anaemia and general weakness. In some cases, protein in the urine (proteinuria) is also detected.

Imerslund Gräsbeck Syndrome is not curable; however, with early diagnosis it can be effectively managed through consistent and lifelong vitamin B12 supplementation. With appropriate treatment, affected dogs can achieve a good quality of life.