# Ruxolitinib reverses systemic vasculitis driven by JAK2 V617F–mutated essential thrombocythemia: a case report

## TL;DR

A 60-year-old man with a specific blood disorder and vasculitis improved after treatment with ruxolitinib, suggesting it may help similar cases.

## Contribution

This case report demonstrates ruxolitinib's effectiveness in treating vasculitis linked to JAK2 V617F-mutated essential thrombocythemia.

## Key findings

- Treatment with ruxolitinib and hydroxycarbamide reduced platelet counts and improved vasculitis.
- No further cardiovascular events occurred after treatment initiation.
- The case suggests ruxolitinib may be a viable treatment for vasculitis in JAK2-mutated essential thrombocythemia.

## Abstract

Vasculitis associated with myeloproliferative neoplasms is rare, and reports on its treatment are limited. Herein, we report a case of Janus Kinase2 (JAK2) V617F mutation–positive essential thrombocythemia (ET) associated with vasculitis.

A 60-year-old man with JAK2 V617F mutation–positive ET underwent coronary artery bypass grafting after recurrent myocardial infarctions and coronary stent occlusions. Intraoperative and pathological findings led to a diagnosis of vasculitis. Treatment with hydroxycarbamide and ruxolitinib resulted in decreased platelet counts and improved vasculitis, with no subsequent recurrence of cardiovascular events.

This rare case shows that ruxolitinib can be effective in treating vasculitis complications in patients with JAK2 mutation–positive ET.