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.