Pernicious anaemia risk factors

What are the risk factors for developing pernicious anaemia and which of these does Mrs HJ have ... 

The initial dose in cobalamin deficiency anaemias, including uncomplicated pernicious anaemia, is hydroxocobalamin 1 mg i.m. every 2-3 days for 5 doses to induce remission and to replenish stores. Maintenance may be 1 mg every 3 months higher doses will not find binding sites and will be eliminated in the urine. Higher doses are justified during renal or peritoneal dialysis where hydroxy-cobalamin clearance is increased, and resultant raised plasma methylmalonic acid and homocysteine represent an independent risk factor for vascular events in these patients (see later). 

Elsborg L, Mosbech J (1979) Pernicious anaemia as a risk factor in gastric cancer. Acta MedScand206 315-318... 

Gastric adenocarcinoma is the most common primary gastric tumour and the third most common GI malignancy. Exposure to environmental risk factors has a major role in the development of gastric carcinoma. There is a positive association with H. pylori and pernicious anaemia. The diagnosis by double-contrast barium meal has been largely replaced by endoscopy with the added advantage of simultaneous biopsy. 

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