[Pernicious anemias with subtle or atypical presentation]

To assess the prevalence and clinico-biologic characteristics of pernicious anaemia (PA) showing subtle or atypical onset.

One-hundred and twenty-four patients were found to fulfill criteria for PA (serum vitamin B12 deficiency due to absence of intrinsic factor secretion because of severe gastric atrophy). Of them were disclosed those lacking macrocytosis (MCV less than 98 fL), with or without anaemia (Hb less than 120 g/L in women and less than 14 f/L in men), but showing decreased serum B12 rates (less than 150 pmol/L).

Macrocytosis was absent in 15 out of the 124 cases (12.1%); either they had anaemia or not, serum B12 rates were decreased in all cases. Eight patients had concurrent iron deficiency, one had secondary anaemia, two had polycythaemia and four were normal from a haematological standpoint. Serum B12 assays were performed because of neuropsychiatric impairment (2 cases), polycythaemia study (3 cases), or positive anti-parietal cell antibodies found in an immunologic study (4 cases). The remaining patients were studied for chronic atrophy of the gastric mucosa (2 cases), and Plummer-Vinson syndrome, leucopenia and nutritional assessment (1 case of each condition).

Atypical presentation of pernicious anaemia, whose frequency is probably underestimated, was confirmed in our environment. This condition must be suspected and ruled out in patients with characteristics similar to those described above.