Acquired von Willebrand Syndrome Complicating Nephrotic Syndrome: A Case of a Patient With Membranous Nephropathy

Abstract

Acquired von Willebrand syndrome (AVWS) is a rare clinical entity presenting with heterogeneous hemorrhagic manifestations, although some subsets of patients with AVWS may be asymptomatic until they are exposed to major trauma, an invasive procedure, or surgery. We herein report one such case in a 73-year-old male patient with nephrotic syndrome with a prolonged active partial thromboplastin time. We initially did not deal with this distinct abnormal clotting profile seriously, but persistent bleeding after a retroperitoneoscopic-assisted renal biopsy that allowed us to ascribe his nephrotic syndrome to membranous nephropathy fortuitously led to the discovery of concurrent AVWS. We feel that an accurate and prompt diagnosis as well as awareness of the disease remain a challenge for physicians and therefore strongly recommend the further accumulation of experiences similar to our own in a prospective manner. This report underscores the pitfalls associated with determining the bleeding risk, including an insufficient assessment and improper weighting of an abnormal clotting profile prior to the invasive procedure. Several management concerns that emerged in the current case are also discussed.

Keywords: Acquired von Willebrand syndrome; atrial fibrillation; membranous nephropathy; prophylactic anticoagulation; retroperitoneoscopic-assisted renal biopsy.

Figure 1.

An electrophoretic analysis of von Willebrand factor (VWF) multimers. The patient’s plasma (P) multimer pattern is unusual and characterized by the presence of only a few bands around the corresponding region of smallest VWF protomer (bottom) without the discontinuous multimer pattern proper of pooled normal plasma (NP) VWF.

Figure 2.

The renal biopsy findings. A light micrograph (A) shows the glomerulus with minor structural abnormalities (periodic acid-Schiff staining). The capillaries are patent, and the basement membranes are delicate. An electron micrograph of a portion of the glomerulus (B) demonstrates scattered segmental subepithelial electron-dense deposits (arrowhead) with distinct but sporadic intervening spikes (arrows), compatible with membranous nephropathy stage I to II. The scale or scale bar is indicated in each panel.