Masked Polycythemia Vera and Iron Deficiency in a Fertile-Age Woman

Area of Science:

• Hematology
• Oncology

Background:

• Polycythemia vera (PV) is a myeloproliferative neoplasm characterized by increased red blood cell (RBC) mass.
• The V617F Janus kinase 2 (JAK2) mutation is common but not exclusive to PV.
• Current diagnostic criteria for PV have lower thresholds for hemoglobin (Hb) and hematocrit (Htc), improving sensitivity.

Observation:

• A case of a fertile-age woman with menometrorrhagia experienced delayed PV diagnosis due to iron depletion masking elevated Hb and Htc.
• Clinical signs including splenomegaly, iron deficiency, and low erythropoietin prompted further investigation.
• Correction of iron deficiency revealed underlying erythrocytosis, leading to PV diagnosis via JAK2 mutation testing and bone marrow biopsy.

Findings:

• Masked PV can present with symptomatic disease despite not meeting diagnostic criteria.
• Iron depletion in women of reproductive age can obscure PV diagnosis by lowering Hb and Htc.
• Low erythropoietin levels and splenomegaly are key indicators for PV in such cases.

Implications:

• Increased clinical suspicion for PV is crucial in fertile-age women with iron depletion and normal Hb/Htc.
• Recognizing masked PV is vital for timely diagnosis and management.
• This case underscores the importance of considering PV even when standard diagnostic thresholds are not met.