Kidney Week

Abstract: TH-PO544

A Case of Intravascular Large B-Cell Lymphoma Diagnosed by Renal Biopsy

Session Information

• Trainee Case Reports - I
  October 25, 2018 | Location: Exhibit Hall, San Diego Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Trainee Case Reports

• 1502 Pathology and Lab Medicine: Clinical

Authors

• Oba, Rina, The Jikei University School of Medicine, Minato-ku, TOKYO, Japan

Rina Oba,

• Koike, Kentaro, The Jikei University School of Medicine, Minato-ku, TOKYO, Japan

Kentaro Koike,

• Nakaosa, Naoko, The Jikei University School of Medicine, Minato-ku, TOKYO, Japan

Naoko Nakaosa,

• Okabe, Masahiro, The Jikei University School of Medicine, Minato-ku, TOKYO, Japan

Masahiro Okabe,

• Matsumoto, Kei, The Jikei University School of Medicine, Minato-ku, TOKYO, Japan

Kei Matsumoto,

• Kawamura, Tetsuya, The Jikei University School of Medicine, Minato-ku, TOKYO, Japan

Tetsuya Kawamura,

• Tsuboi, Nobuo, The Jikei University School of Medicine, Minato-ku, TOKYO, Japan

Nobuo Tsuboi,

• Yokoo, Takashi, The Jikei University School of Medicine, Minato-ku, TOKYO, Japan

Takashi Yokoo,

Group or Team Name

• The Jikei University School of Medicine, Division of Nephrology and Hypertension, Department of Internal Medicine.

Introduction

Intravascular large B-cell lymphoma (IVLBCL) is a rare subtype of large-cell lymphoma characterized by the proliferation of lymphoma cells within small vessels. In general, patients with IVLBCL exhibit aggressive clinical courses and most cases are diagnosed at autopsy. Although recent advancements in chemotherapy have markedly improved patient prognosis, an early diagnosis by biopsy remains critical. Therefore, random skin biopsy or bone marrow biopsy is performed in most cases. To date, some case reports have mentioned IVLBCL diagnosis by liver, lung, and brain biopsies. Here, we report a rare case of IVLBCL diagnosed by renal biopsy in a patient with the clinical phenotype of persistent proteinuria together with an elevated serum titer of proteinase-3-anti-neutrophil cytoplasmic antibody (PR3-ANCA).

Case Description

The patient was a 66-year-old woman with a history of bilateral leg edema, erythema, and pruritis. Laboratory data revealed high serum PR3-ANCA titer (92.6 U/ml), and chest computed tomography revealed lung nodules. Four months after the first presentation, the patient developed rapidly progressing dyspnea and persistent proteinuria (1.22 g/day) without hematuria. Renal biopsy revealed intraglomerular infiltration of enlarged atypical lymphocytes. Immunofluorescent staining showed that these cells were characterized as CD3-, CD5-, CD20+, CD79a+, CD10-, bcl-6+, and MUM1+. On the basis of these findings, the patient was eventually diagnosed with IVLBCL. After several cycles of chemotherapy, her proteinuria decreased (0.04 g/day) and PR3-ANCA titer declined (11.3 U/ml).

Discussion

We report a rare case of IVLBCL accompanied with persistent proteinuria and an elevated serum PR3-ANCA titer. In this case, identification of large lymphoma cells within the small vessels of the kidney was a key factor for early diagnosis and successful treatment.