The value of the intrinsic factor antibody test in diagnosing pernicious anaemia

Assessment of the usefulness of the intrinsic factor antibody (IF Ab) test in comparison to the Schilling test in diagnosing pernicious anaemia (PA) in patients with vitamin B12 deficiency.

This study was designed to compare the If Ab test to the Schilling test using results obtained of patients presenting with megaloblastic anaemia and low serum vitamin B12 levels to a large referral hospital.

The Chris Hani Baragwanath Hospital, Soweto, Gauteng, South Africa.

Results from 77 patients with megaloblastic anaemia, low serum vitamin B12 levels and with both Schilling and IF Ab test results available were included.

The sensitivity and specificity of the IF Ab test was compared to the Schilling test with regard to making a diagnosis of PA in patients presenting with megaloblastic anaemia and low serum vitamin B12 levels.

Relevant statistical analysis showed that in the correct clinical setting, a confident diagnosis of PA could be made without Schilling tests in patients with megaloblastic anaemia, vitamin B12 deficiency and positive IF Ab tests. In a small proportion of patients in whom the IF Ab is negative, Schilling tests still need to be performed.

With the increased concern over rising medical costs and where limited facilities are available, the IF Ab, in the correct clinical setting, is a cost effective and reliable test for diagnosis of PA.