Introduction: -
Polycythemia vera is a Philadelphia‐negative myeloproliferative neoplasm
(MPN) characterized by increased red blood cell mass, bone marrow
panmyelosis, and the presence of either a JAK2V617F or a JAK2 exon 12
mutations.
PV is diagnosed according to The World Health Organization by the
presence of major diagnostic criteria, including an elevated hemoglobin
or hematocrit level, abnormal results on bone marrow biopsy, and
presence of the Janus kinase 2 genetic mutation, which is present in
approximately 98% of cases. The only minor criterion is a subnormal
erythropoietin level, which helps differentiate polycythemia vera from
common causes of secondary erythrocytosis [1,2].
Patients with PV may experience a broad symptom burden that include
constitutional symptoms such as fatigue, weight loss, night sweats and
pruritus, mild-to moderate degree of splenomegaly, symptoms of
hyperviscosity, microvascular symptoms (e.g., headaches,
lightheadedness, visual disturbances, atypical chest pain,
erythromelalgia, paresthesia), and thrombotic and bleeding complications
[3,4].
Pruritus is one of the common clinical features of PV. In addition,
PV-associated pruritus is often triggered by contact with water at any
temperature, called ‘aquagenic pruritus’ (AP). Pruritus has been noted
in 5–69% of PV patients.
PV-associated pruritus can directly result in substantially impaired
quality of life. There are different ways to manage PV-related pruritis,
including antihistamine, IFN-a 2b, Phototherapy, and cytoreduction.
Ruxolitinib, a JAK-2 inhibitor, recently started to be used to treat PV
pruritis, especially in patients who had an inadequate response or had a
side effect of hydroxyurea [1,5].
In this case, our PV patient had severe pruritis, which was not
improving with antihistamine, local steroids, cytoreduction, and
phlebotomy.
When we started the patient on low dose Ruxolitinib, the patient’s
symptoms improved slightly, so we increased the dose to a high dose
which showed dramatic improvement.