Polycythemia vera (PV) is a myeloproliferative neoplasm primarily
characterized by erythrocytosis. PV incidence is exceedingly rare in the
pediatric and adolescent population. In adult patients, approximately
96% are found to have a somatic mutation in exon 14 (JAK2 V617F) and
3% display a mutation in exon 12. We present a case of a 2-year-old
female with symptomatic PV secondary to a deletion in exon 12 of JAK2,
initially treated with phlebotomy and switched to PEG-IFNα-2a therapy.
This therapy has been effective over 15 months with resolution of
symptoms, reduced phlebotomy requirements, and minimal side effects.