How to diagnose Imerslund-Grasbeck syndrome ?
How is Imerslund-Grasbeck syndrome diagnosed? The diagnosis of Imerslund-Grasbeck syndrome (IGS) is made after a series of tests are performed. Cobalamin deficiency is typically detected first, followed by showing that cobalamin is poorly absorbed (the main cause of cobalamin deficiency). Other known causes of vitamin B12 malabsorption must then be ruled out. Lastly, it must be shown that after correcting the deficiency, the only nutrient to be poorly absorbed is vitamin B12. The diagnosis can also be confirmed by having genetic testing of the genes that are known to cause the condition. While the presence of proteinuria is strongly suggestive of IGS, not all affected individuals have proteinuria.