Angioimmunoblastic T-cell Lymphoma Associated with IgA Nephropathy

Abstract

Few cases of IgA nephropathy with angioimmunoblastic T-cell lymphoma (AITL) have been reported. We herein present the case of a 79-year-old Japanese man with AITL and IgA nephropathy. The patient presented with generalized edema, fatigue, and fever. Laboratory investigations revealed polyclonal gammopathy with a high level of IgA, microscopic hematuria, proteinuria, and some other immunological abnormalities. Computed tomography revealed generalized lymphadenopathy. A diagnosis of AITL and IgA nephropathy was made based on inguinal lymph node and renal biopsies. Following chemotherapy for AITL, the patient's edema, microscopic hematuria, and proteinuria were alleviated. These findings indicate that IgA nephropathy may occur in AITL patients.

Figure 1.

Inguinal lymphoid biopsy. (a) A low power view of an inguinal lymph node biopsy specimen [Hematoxylin and Eosin (H&E) staining, ×25]. The normal lymph node architecture is almost completely effaced and the diffuse infiltration of lymphoid cells is observed. (b) A moderate-power view of the inguinal lymph node biopsy specimen (H&E staining, ×100). The aggregation of medium-sized atypical lymphoid cells and marked vascular proliferation can be observed. The neoplastic lymphoid cells have a clear to pale cytoplasm and convoluted nuclei with dispersed chromatin. Immunohistochemical staining for (c) CD3 (×100), (d) CD10 (×100), (e) CXCL13 (×100), and (f) CD21 (×50) revealed that most of the neoplastic cells showed CD3 positivity; the cells were negative for CD10 expression but some expressed CXCL13. The CD21 immunohistochemistry highlights the expansion of follicular dendritic cells. (g) EBV EBERin situ hybridization (×100) showing the marked infiltration of EBV-positive B cells. CD: Cluster of differentiation, CXCL: C-X-C motif chemokine ligand, EBER: Epstein-Barr-virus-encoded small RNA, EBV: Epstein-Barr virus

Figure 2.

Renal biopsy. (a) Light microscopy, focal infiltration by small to medium-sized atypical lymphoid cells can be seen in periglomerular and peritubular regions (Hematoxylin and Eosin staining, ×40). (b and c) An immunofluorescence examination showing mesangial deposits of (b) IgA (×40) and (c) C3 (×40). (d) An electron microscopic image (×3,000) showing a small amount of dense deposits in the mesangial matrix. C3: complement component 3, IgA: immunoglobulin A