Association of co-existing vitamin B6 and B12 deficiency with polyneuropathy, organomegaly, endocrinopathy, M protein, and skin changes (POEMS) syndrome: a case report.

Background: Both vitamin B6 deficiency and vitamin B12 deficiency can present with symptoms that appear like polyneuropathy, organomegaly, endocrinopathy, M protein, and skin changes (POEMS) syndrome, with painful peripheral neuropathy and sensorimotor dysfunction. There are rare reports of an association between vitamin B12 deficiency and POEMS syndrome, and even rarer reports of an association between vitamin B6 deficiency and POEMS syndrome. To our knowledge, this is the first described case with deficiencies in both vitamin B6 and vitamin B12 in association with POEMS syndrome.

Case presentation: A man in his 40s presented with fatigue, imbalance, and painful numbness and tingling. Initial evaluation revealed low vitamin B12 level, and he received oral and IV supplementation for one month with an improvement in vitamin B12 levels, but without improvement in symptoms. Further evaluation revealed both a vitamin B6 deficiency and an IgA lambda monoclonal spike, prompting further investigation and an eventual diagnosis of POEMS syndrome. He underwent an autologous stem cell transplant and has had improvement in his symptoms.

Conclusions: Patients with POEMS syndrome may have symptoms that are difficult to distinguish from deficiencies in vitamin B6 or vitamin B12. Management of POEMS should include screening of vitamin B6 and B12 to ensure other possible associated causes of symptoms are appropriately treated.