Primary myelofibrosis associated glomerulopathy: significant improvement after therapy with ruxolitinib

Myeloproliferative Neoplasm and Myelodysplastic Syndrome-Associated Renal Disease: A Histopathological Report of Two Cases

Myeloproliferative neoplasms (MPN) are clonal disorders of hematopoietic stem cells with a proliferation of one or more myeloid lineage and mature cell overproduction, while myelodysplastic syndrome (MDS)/MPN simultaneously show aspects of MDS and MPN, leading to partially ineffective hematopoiesis with associated dysplastic changes. This spectrum of disorders includes chronic myeloid leukemia, polycythemia vera, primary myelofibrosis, and essential thrombocythemia. MDS/MPN are classically not associated with renal complications; however, an accumulating body of evidence suggests that multiple growth factors, cytokines, endothelial damage, and an activated complement system in these patients can induce glomerulopathy, as nearly a third of these patients present with advanced renal disease on diagnosis, which is unlikely to be age or hypertension-related. In this report, we present two cases of patients with MPN/MDS, a 45-year-old male with essential thrombocythemia and a 73-year-old male with polycythemia vera, both of whom developed generalized edema and were referred to our institution from their outpatient nephrologists due to accompanying proteinuria. Renal biopsy of the first patient revealed mesangiocapillary and mesangioproliferative MPN-associated glomerulopathy. In contrast, the second patient was diagnosed with MPN/MDS-associated segmental mesangial proliferative glomerulonephritis and renal vasculature drug toxicity. Both patients were started on treatment - corticosteroid as per consensus.

Renal disease associated with myeloproliferative neoplasms and myelodysplastic syndrome/myeloproliferative neoplasms

AIMS

Renal changes in patients with myeloproliferative neoplasms (MPNs) or myelodysplastic syndrome (MDS)/MPNs have been addressed by few, respectively no, reports. The aim of this study was to focus on a systematic evaluation of renal biopsies in patients with MPNs or MDS/MPNs.

METHODS AND RESULTS

The cohort comprised 29 patients (23 men) aged 67 ± 11 years (mean ± standard deviation), diagnosed with chronic myeloid leukaemia (n = 5), polycythaemia vera (n = 9), primary myelofibrosis (n = 5), essential thrombocythaemia (n = 2), or chronic myelomonocytic leukaemia (n = 4), as well as MPNs or MDS/MPNs not otherwise specified (n = 4). Patients manifested with proteinuria (93%), partially in the nephrotic range (46%), haematuria (72%), and impaired kidney function (93%). The most prominent histological findings included double-contoured glomerular basement membranes (71%), acute endothelial damage (68%), intracapillary platelet aggregation (62%), mesangiolysis (21%), thrombotic microangiopathy (24%), segmental glomerulosclerosis (66%), mesangial hypercellularity and sclerosis, extramedullary haematopoiesis (17%), and also IgA nephropathy (21%) and glomerulonephritis (GN) with features of infection-related GN (21%). MPN and MDS/MPN patients showed significantly more chronic changes than age-matched and sex-matched controls, including global and segmental glomerulosclerosis, mesangial sclerosis, and hypercellularity, whereas the extent of arteriosclerosis was comparable.

CONCLUSIONS

MPN and MDS/MPN patients show glomerular scarring that exceeds age-related phenomena. Ongoing endothelial damage, growth factors released by platelets and deposition of immune complexes are probably the causative mechanisms. Early recognition of renal failure heralded by proteinuria and haematuria, and consequent control of risk factors for kidney failure, should be recommended for MPN and MDS/MPN patients.

Kidney Involvement in Patients With Chronic Myelomonocytic Leukemia or BCR-ABL-Negative Myeloproliferative Neoplasms

Introduction

The identification of specific molecular signatures and the development of new targeted drugs have changed the paradigm of onco-nephrology, now allowing a multiscale approach of kidney involvement related to hematologic malignancies relying on combined hematologic and molecular assessments. In this study, we aimed to refine the spectrum of kidney disorders associated with chronic myelomonocytic leukemia (CMML) or BCR-ABL–negative myeloproliferative neoplasms (MPNs), 2 very rare conditions scarcely described.

Methods

Case series. Patients with myeloid neoplasms who were referred to Toulouse University Hospital Nephrology Unit and were diagnosed with acute kidney injury (AKI), chronic kidney disease (CKD), or urine abnormalities were retrospectively included.

Results

Eighteen patients (males n=13, CMML n=8, essential thrombocytosis [ET] n=7, polycythemia vera [PV] n=1, and myelofibrosis n=2) developed kidney disease 7.7±2 years after the diagnosis of the malignancy. Twelve patients had AKI at presentation. Eight patients had glomerular presentation (high-range proteinuria 33%, microscopic hematuria 56%). Kidney biopsy (n=14) showed various patterns, including pauci-immune glomerulosclerosis (n=5), extramedullary hematopoiesis (n=6), or tubular atrophy and interstitial fibrosis with polymorphic inflammation (n=8). Immunostaining of CD61 confirmed the infiltration of megakaryocytes within glomeruli or interstitium in 5 of 8 patients. Other pictures of glomerulopathy were identified in 3 patients (IgA nephropathy n=2, AA amyloidosis n=1). Massive kidney infiltration by CMML was identified in 1 patient. After a mean follow-up of 24±6 months, malignancy was considered as stable in 11 patients (61%), but 22% of patients had progressed to end-stage renal failure. The remaining had persistently reduced kidney function. No correlation between the malignancy and the renal presentation and outcomes could be identified.

Conclusions

Kidney complications of CMML/MPN are heterogenous, and kidney biopsy may help to identify new molecular targets to prevent the development of kidney fibrosis.

Focal segmental glomerulosclerosis in a patient with prefibrotic primary myelofibrosis

We report a case of 56-year-old man presented to us with chief complaints of frothy urine and leg swelling. A urinalysis revealed nephrotic-range proteinuria. Haematological investigations revealed thrombocytosis, leucocytosis and peripheral blood smear showed a leucoerythroblastic picture. JAK 2 mutation was positive. To confirm the diagnosis of myeloproliferative neoplasm, bone marrow biopsy was done, which was suggestive of primary myelofibrosis. The patient underwent kidney biopsy due to rapidly declining renal function and persistent proteinuria, which was suggestive of focal segmental glomerulosclerosis. Early glomerulopathy is rare in myeloproliferative neoplasm, and aggressive follow-up is required to prevent progression of kidney disease.

WITHDRAWN: Nephrotic syndrome in primary myelofibrosis with renal extramedullary hematopoiesis and glomerulopathy in the JAK inhibitor era

Ahead of Print article withdrawn by publisher. The publisher apologizes for any inconvenience this has caused. The article was scheduled for the journal "Clinical Nephrology. Case Studies" (issn 2196-5293). The article is available in PubmedCentral: https://www.ncbi.nlm.nih.gov/pubmed/29350220 
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Hydroxyurea for Treatment of Nephrotic Syndrome Associated With Polycythemia Vera

Myeloproliferative disorders are a rare cause of focal segmental glomerulosclerosis (FSGS), although the mechanism is unclear. Hydroxyurea is commonly used in these disorders for its cytoreductive properties; however, the effect of this treatment on proteinuria or kidney function remains unclear in cases of myeloproliferative disorder-associated FSGS. We describe the clinical course of a patient with polycythemia vera and nephrotic-range proteinuria, demonstrated to have FSGS on biopsy. The patient had a distant history of granulomatosis with polyangiitis (Wegener's), for which he routinely had his kidney function and proteinuria measured, allowing for early detection of nephrotic syndrome soon after being diagnosed with polycythemia vera. Treatment with hydroxyurea resulted in rapid improvement in proteinuria that correlated with a decrease in hematocrit. This response was replicated 2 additional times when the patient was taken off and then restarted on hydroxyurea therapy. He now maintains a steady dose of hydroxyurea with favorable kidney measures (proteinuria with <1g/d of protein excretion and serum creatinine of 1.27mg/dL [corresponding to estimated glomerular filtration rate of 56mL/min/1.73 m(2)]). This case suggests that early screening and treatment for myeloproliferative disorder-associated FSGS may lead to improved long-standing kidney function.