JAK2 mutation–positive polycythaemia vera associated with IgA vasculitis and nephrotic syndrome: a case report

Abstract

We report a case of polycythaemia vera (PV) associated with IgA vasculitis. A 45-year-old man was admitted for evaluation of abdominal pain and palpable purpura. IgA vasculitis was diagnosed, and oral prednisolone therapy (30 mg/day) was initiated. On day 6, the patient developed left hemiparesis, and magnetic resonance imaging revealed acute cerebral infarction. Bone marrow biopsy results and the identification of a Janus kinase 2 (JAK2) mutation led to the diagnosis of PV. Despite steroid therapy, urine protein levels increased to 15 g/g・Cre. Renal biopsy demonstrated mild mesangial proliferation with IgA deposits, but immunosuppressive therapy was partially effective. This case suggests that PV can be a complication of IgA vasculitis and that preventive measures for thrombosis should be taken in such cases.

Keywords:

• IgA vasculitis
• Janus kinase 2 (JAK2)
• myeloproliferative neoplasms
• nephrotic syndrome
• polycythaemia vera

Patient consent

Written informed consent to publish this case report was obtained from the patient.

Conflict of interest

None.

Ethical approval

Not applicable.

Authors’ contributions

HK, RW, SO, KK, TO, GY, AS, HC, AT, TI, and MK provided medical care for the patient in the case report. ST performed a pathological assessment of the case. HK and RW wrote the manuscript. HK, RW, HH, and HF finalised the manuscript.