Autoantibodies to intrinsic factor can jeopardize pernicious anemia diagnosis: a case report.

Vitamin B12 deficiency may cause neurological and hematological alterations. Its assessment should be easy considering that the access to its measurement is available in majority of the clinical laboratories. The presence of technical interference when measuring vitamin B12 can lead to an erroneous or a more difficult diagnosis of conditions as pernicious anemia. We report a case in which an interference in the evaluation of vitamin B12 concentration led to the realization of invasive tests and almost a misdiagnosis of a patient who actually had pernicious anemia. Professionals need to be aware of these interferences when we assess outcomes.