Renal Involvement by Hematopoietic Neoplasms
Mark Shuldberg, David S Brink, Guilan Chen. Saint Louis University School of Medicine, St. Louis, MO
Background: Renal manifestations of some hematopoietic disorders are well-recognized. Specific associations such as immunoglobulin cast nephropathy and light chain deposition disease (LCDD) with multiple myeloma (MM) or monoclonal gammopathy of undetermined significance (MGUS) are extensively characterized. Direct renal involvement by a hematopoietic neoplasm is rarely described.
Design: A retrospective analysis of all kidney biopsies examined at Saint Louis University from 2000 to 2012 was performed. The renal manifestations were categorized, and the incidence of each category was calculated. Patients with renal involvement by the underlying hematopoietic neoplasms were identified. Presenting clinical and laboratory findings were obtained. Pathology material was reviewed.
Results: Out of a total of 4522 kidney biopsies, 130 recorded a hematopoietic disorder (69% with MM or MGUS). Of these, 121 were native kidneys, and 9 were allografts. The mean age at presentation was 64. The male:female ratio was 1.55:1. Indications for biopsy included (from most common to least) renal insufficiency, proteinuria, nephrotic syndrome, and hematuria. On biopsy, 47 (36%) had hypertensive change, 28 (21%) cast nephropathy, 24 (18%) amyloidosis, 17 (13%) diabetic nephropathy, 16 (12%) immunoglobulin deposition disease, 11 (8%) focal segmental glomerulosclerosis. Less frequent biopsy diagnosis includes acute tubular injury, interstitial nephritis, fibrillary glomerulonephritis, membranous glomerulonephropathy, acute rejection and calcineurin inhibitor toxicity. One patient had neoplastic plasma cells (kappa-restricted) involving the kidney. Two patients had post transplant lymphoproliferative disease (PTLD) in the form of lymphoma. One patient with myelofibrosis had extramedullary hematopoiesis (EMH) in the allograft kidney.
Conclusions: Renal manifestations of hematopoietic disease are not uncommon. It is not surprising to find a high percentage of cast nephropathy, amyloidosis and LCDD in our patient pool with high percentage of MM or MGUS. Renal infiltration by a hematopoietic neoplasm is rare: in this study, only one MM patient had renal infiltration by neoplastic plasma cells, and only two transplant patients had renal PTLD. Though neoplastic hematopoietic infiltration of the kidney appears rare, its true incidence is unknown. A large multicenter study or national registry is needed to accurately assess its incidence. In addition, one renal allograft showed EMH in the setting of myelofibrosis. It is important to be aware of this rare occurrence, since EMH can mimic acute cellular rejection as well as acute interstitial nephritis.
Category: Kidney (does not include tumors)
Monday, March 4, 2013 1:00 PM
Poster Session II # 230, Monday Afternoon