Renal infarction due to polyarteritis nodosa in a patient with angioimmunoblastic T-cell lymphoma: a case report and a brief review of the literature

A 40 year-old-male patient presented to his general practitioner with a 3-weeks history of myalgia, arthralgia, fever (37.5°C) and cough which persisted despite a broad-spectrum antibiotic therapy. For this, he underwent a chest X-ray examination which showed bilateral lung nodules and enlarged mediastinal lymph nodes, with a clinical picture consistent with sarcoidosis. The patient was admitted to the Pneumologic Unit of Siena University Hospital. On admission, physical examination showed generalized lymphadenopathy, splenomegaly and skin rash. The laboratory data are summarized in Table 1. The blood count, liver and renal function, as well as angiotensin converting enzyme (ACE), were within the reference range. Eosinophilia and hypergammaglobulinemia were not found whereas C-reactive protein, lactate dehydrogenase, β2-microglobulin and serum immunoglobulins were increased. Since the clinical picture was doubtful, the patient underwent biopsy of the axillary lymph node, the maximum diameter of which was 3 cm. On the basis of clinical presentation and histological findings, the diagnosis of angioimmunoblastic T-cell lymphoma stage IVB was made according to the criteria of WHO classification [1]. The patient received a combination chemotherapy with pegylated liposomal doxorubicin (30 mg/m², day 1), cytarabine (2 g/m² day 2–3) and dexamethasone (40 mg day 1–4) every 21 days. After two cycles, the patient presented a marked improvement of the systemic symptoms and no superficial lymphadenopathies were observed. After 3 months a re-stage whole body computed tomography (CT)-scan was performed which showed the disappearance of all previous pathologic findings, but evidenced a lesion of 45 mm in the lower pole of the left kidney (Figure 1). Such finding was later confirmed by an ultrasound scan, that showed, at the color Doppler exam, a vascular pattern consistent with renal cell carcinoma. The patient was readmitted to the Hospital in order to perform a nephrectomy. The final diagnosis was renal infarction due to PAN, according to Carlson [18]. The patient had negative rheumatoid factor, HLA-B27, streptolysin O, anti-nuclear, anti-cardiolipin, anti-DNA, anti-smith, anti-RNP, anti-SSA, anti-SSB, anti-neutrophil cytoplasmic and anti-lupus anticoagulant antibodies. Serologies and PCR for both HBV and HCV were negative. The histological diagnosis of PAN was also confirmed by clinicians according to American College of Rheumatology (ACR) criteria [19]. After six days, the patient was discharged from hospital without complications. He completed the chemotherapy induction program (4 cycles) and underwent consolidation with high-dose chemotherapy and autologous stem cells transplantation. He is well five years after surgery.

Serial sections of both axillary lymph node and left kidney were performed, routinely processed, stained with haematoxylin and eosin and examined by light microscopy. Histologically, the lymph node architecture was partially effaced by polymorphic cellular infiltration, burnt-out follicles (Figure 2A) and proliferation of numerous arborizing high-endothelial venules (Figure 2B). An expansion of paracortex was observed, which was diffusely infiltrated by a polymorphous population of small to medium-sized lymphocytes, with distinct cell membranes, clear to pale cytoplasm, and mild irregular nuclei (Figure 2C). The neoplastic population was admixed with small reactive lymphocytes, eosinophils, plasma cells, histiocytes and numerous follicular dendritic cells. Few large immunoblast-like lymphoid cells with large distinct nuclei and clear cytoplasm were observed intermingled with lymphocytes. In addition, scattered Reed-Sternberg (RS)-like cells with irregular multilobated nuclei and large eosinophilic nucleoli were present in the node. Immunohistochemically, the neoplastic T-cells were positive for CD45Ro, CD3, CD10, LANA-1 and LMP and expressed mostly the CD4 antigen (Figure 2D), although numerous reactive CD8 positive T-cells were present. CD20, CD79a, PAX-5, CD56, MUM-1 and CD30 were negative. The large immunoblast-like cells and the scattered RS-like cells showed immunoreactivity to CD20, CD79a and CD30. The proliferation of follicular dendritic cells highlighted by CD21 and CD23 was prominent throughout the node, and entrapped high-endothelial venules. By means of in situ hybridization RNAs (EBERs), EBER-positive signals were observed in scattered large B immunoblasts and RS-like cells (Figure 2D, inset). Molecular studies showed monoclonal rearrangement of T-cell receptor genes and polyclonal rearrangement of immunoglobulin heavy chain (IgH) receptor. Macroscopic examination of the left kidney specimen showed a large pale area at the lower pole, approximately 4 cm in maximum diameter with a triangular morphology, centered on the renal cortex and consistent with an infarcted area (Figure 3A). Coagulative necrosis of renal parenchyma (Figure 3B) and multiple segmentary inflammatory lesions of small and middle renal arteries were observed on histological examination. Masson and Giemsa stains showed rupture of internal elastic lamina with aneurysmal collapse of the arterial wall (Figure 3C). Some vascular lumina were obliterated by fibrous stroma and sometimes recanalized by thin vascular channels (Figure 3D). There was no infiltration by neoplastic T-cells.