A case report and literature review of IgA nephropathy presenting as nephrotic syndrome in polycythemia vera.

A 66-year-old non-smoker presented with a 2-week history of new-onset pedal oedema and gross haematuria. On evaluation, he was found to be hypertensive and oedematous with a haemoglobin of 19.1 g/dl, platelet count of 546,000/mm ³ , and creatinine of 2.6 mg/dl. Urine examination revealed abundant RBCs with 3+ albumin on three separate occasions. His 24-h urine protein level was 3830 mg/day, with a serum cholesterol level of 303 mg/dl. Secondary erythrocytosis and thrombocytosis tests were negative. Bone marrow examination revealed hypercellularity, erythroid hyperplasia, tight clusters of large megakaryocytes, and megakaryocytic hyperplasia suggestive of polycythemia vera. PCR analysis revealed a JAK2V617 F (exon 14) mutation. In view of nephrotic syndrome, azotemia, and microscopic haematuria, a renal biopsy was performed, which revealed features of IgA nephropathy with advanced interstitial fibrosis and tubular atrophy. He was started on angiotensin receptor blockers with hydroxy urea as a part of treatment. This case report highlights the association of glomerular disease with polycythaemia vera and the need of prompt renal biopsy for diagnosis and management.
Competing Interests: Declarations. Conflict of interest: The authors declare that they have no competing interests. Ethical approval: This case report was drafted after written informed consent of the patient in conformity with CARE clinical case reporting guidelines and Declaration of Helsinki. The authors are accountable for all aspects of the work (including full data access, integrity of the data, and accuracy of the data analysis) to ensure that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.
(© 2024. The Author(s), under exclusive licence to Japanese Society of Nephrology.)