Pernicious anaemia: testing, staging and advances in genetics

Pernicious anaemia is the end result of autoimmune chronic gastritis, a slowly progressive inflammatory disease of the stomach lining that leads to atrophy of gastric parietal cells where intrinsic factor, a substance necessary for vitamin B₁₂ absorption, is produced. The main focus of laboratory testing in cases of suspected pernicious anaemia is confirmation of B₁₂ deficiency and the haematological consequences thereof. An additional approach is afforded by the autoimmune nature of the underlying gastric damage and the associated presence of circulating autoantibodies, and more recently an appreciation of the genetic aspects of this autoimmune condition.

Introduction

The history of progress towards understanding pernicious anaemia (PA) begins in 1872 with publication of descriptive case histories prepared by German physician Anton Biermer. He coined the term pernicious anaemia to emphasise what was then an inevitably fatal outcome. In 1880 Paul Ehrlich determined that this particular type of anaemia is characterised by the presence in blood of large red cell precursors (megaloblasts).