Diagnosis of Polycythemia Vera in an Anemic Patient

The revised World Health Organization diagnostic criteria for polycythemia vera, essential thrombocytosis, and primary myelofibrosis: an alternative proposal

“…In PV, however, the plasma volume usually does not shrink with the development of erythrocytosis and may even expand, particularly in women (Table 1), masking the absolute increase in red cell mass. 39,[56][57][58] Thus, it is not surprising that the WHO hemoglobin or hematocrit guidelines were invalid.…”

“…As a corollary, when PV is a diagnostic consideration, a red cell mass and plasma volume determination or a phlebotomy trial are desirable. Third, plasma volume expansion, even in the absence of splenomegaly, can mask the true increase in red cell mass in PV 39,56,58 (Table 1). As a consequence, hemoglobin or hematocrit values alone cannot be used to establish the presence of erythrocytosis; only red cell mass and plasma volume determinations can.…”

Myeloid Neoplasms in the Guise of Nutritional Deficiency

“…Deficiencies of iron, folic acid, and vitamin B 12 , alone or in combination, have been reported in association with MPN [4–6]. In identifying subtle deficiency of vitamin B 12 and folate, homocysteine and methyl malnoic acid (MMA) are proven to be more sensitive than serum cobalamin and folate.…”

“…Because of their relatively smooth clinical course, it is likely that many classic BCR-ABL negative MPN cases actually go undetected. Deficiencies of iron, folic acid, and Vitamin B 12 are known to occur in association with BCR-ABL-negative MPNs [4–6]. These deficiencies may be coincident, secondary, or perhaps a manifestation of the underlying MPN.…”