Renal involvement in a large cohort of Chinese patients with Castleman disease

Successful outcome in a case of idiopathic multicentric Castleman disease with atypical lymphadenopathy and kidney injury: Diagnostic challenges and treatment approach-Case report

Idiopathic multicentric Castleman disease is a rare and complex disease characterized by systemic inflammation, lymphadenopathy, and multiorgan involvement. This case report presents a 66-year-old Chinese man with idiopathic multicenter Castleman disease without significant lymphadenopathy and challenging diagnosis. Patients present with fever, fatigue, loss of appetite, weight loss, and acute kidney injury. Initially, a urinary tract infection was suspected, but despite anti-infective treatment, the patient's symptoms persisted. Lymph node biopsy, although there is no significant lymphadenopathy, confirms idiopathic multicenter Castleman disease. Treatment includes thalidomide, cyclophosphamide, and dexamethasone, as well as supportive measures and infection control. After 8 months of follow-up, the patient's clinical symptoms, inflammatory markers and renal function were significantly improved, and there was no symptomatic recurrence. This case underscores the importance of considering idiopathic multicenter Castleman's disease in patients with persistent fever and systemic inflammation, even in the absence of significant lymphadenopathy. Early identification and accurate diagnosis of idiopathic multicenter Castleman's disease can lead to the initiation of targeted therapy strategies that ultimately yield favorable outcomes.

A Case of Castleman's Disease with a Marked Infiltration of IgG4-Positive Cells in the Renal Interstitium

Multicentric Castleman's disease (MCD) is a benign lymphoproliferative disorder with heterogenous clinical symptoms, and involves systemic organs in addition to lymph nodes. Herein, we present the case of a 55-year-old man with MCD characterized by an extensive infiltration of IgG4+ plasma cells in the kidneys. The patient presented to our hospital with a high fever and diarrhea. On admission, laboratory analysis revealed anemia, renal dysfunction (eGFR 30 mL/min/1.73 m2), polyclonal gammopathy (IgG 7130 mg/dL), elevated serum IgG4 level (2130 mg/dL), and increased C-reactive protein (8.0 mg/dL). An enlargement of lymph nodes in the axillary, mediastinal, para-aortic, and inguinal regions was observed on abdominal computed tomography. Axillary lymph node biopsy revealed interfollicular expansion due to dense plasma cell infiltration. Renal biopsy demonstrated significant plasma cell infiltration into the tubulointerstitium. Immunohistochemical analysis showed a 40% IgG4-positive/IgG-positive plasma cell ratio, meeting the diagnostic criteria for an IgG4-related disease. Amyloid A deposition was observed along vessel walls, and immunofluorescence analysis indicated granular positivity of IgG and C3 along the glomerular capillary wall. Elevated levels of interleukin-6 (21 pg/mL) and vascular endothelial growth factor (VEGF; 1210 pg/mL) were noted. Based on these findings, and the histological finding of the lymph node biopsy, idiopathic MCD was diagnosed. Corticosteroid monotherapy was only partially effective. Subsequently, tocilizumab administration was initiated, leading to sustained remission, even after discontinuation of prednisolone. Due to the diverse responses to steroid therapy and the varying prognoses observed in MCD and IgG4-related disease, it is essential to carefully diagnose MCD by thoroughly assessing the organ distribution of the disease, its response to steroid therapy, and any additional pathological findings.

Successful Renal Transplant in Castleman Disease - First Case Report from India

Castleman disease (CD) comprises a rare group of heterogenous benign lymphoproliferative disorders with pathologic similarities. However, they present with diverse clinical manifestations. Renal involvement is rare in CD and is mainly reported with plasma cell type of multicentric disease. Various glomerular pathologies, interstitial involvement, or thrombotic microangiopathies have all been reported, some of which progress to end-stage renal disease (ESRD). Progression of CD to ESRD is well documented; however, a patient on dialysis developing CD is rare. Moreover, kidney transplantations have seldom been performed on patients with CD. We report a patient with ESRD of unknown etiology who developed multicentric CD while on dialysis. He was treated with four doses of rituximab and later underwent a living kidney transplant with his wife as a donor. He has been clinically well ever since. We believe that this is possibly the first successful case of renal transplantation in CD with ESRD being reported from India.

Rapid Clinical Improvement of Multicentric Castleman Disease (MCD) with Renal Involvement Following Treatment with Tocilizumab: AA Amyloidosis as a Possible Renal Involvement of MCD

Castleman disease (CD) is a lymphoproliferative disorder that manifests as hypergammaglobulinemia and severe inflammation with multiorgan involvement. However, renal involvement has been infrequently described in CD. We present a case of a 63-year-old Japanese male patient with multicentric CD (MCD) in whom kidney involvement, including impaired renal function and massive proteinuria, is present. He had a 2-year history of inflammatory arthritis and was referred to our clinic with newly developed proteinuria, renal dysfunction, and elevated levels of acute-phase proteins. Abdominal computed tomography scan revealed hepatosplenomegaly, including mesenteric and inguinal lymph node enlargements. The patient underwent inguinal lymph node resection. Excisional biopsy of the inguinal lymph node showed multiple lymphoid follicles and expansion of interfollicular areas by marked plasmacytosis consistent with mixed type CD. The patient was diagnosed with human herpes virus 8-negative MCD according to the international diagnostic criteria for CD. Diagnostic renal biopsy was not performed following the medical viewpoint. Tocilizumab (TCZ) treatment was highly effective in reducing proteinuria and stabilizing renal function, as well as improving other clinical symptoms. The patient responded to TCZ treatment, and the renal involvement was rapidly improved. Our preliminary immunohistochemical analysis indicated AA amyloid deposits in urinary epithelial cells suggesting a possible renal involvement of AA amyloidosis. TCZ could potentially be one of the therapeutic options in patients with MCD with renal involvement.

Recent advances in IgG4-related kidney disease

Recent advances in the management and understanding of immunoglobulin (Ig)G4-related kidney disease (RKD) have emphasized the importance of urgent treatment in IgG4-related tubulointerstitial nephritis. On the other hand, to avoid long-term glucocorticoid toxicity, strategies for early withdrawal of steroids or combination of immunosuppressants, such as rituximab, and the minimum dose of steroids have been pursued. However, disease recurrence after reducing or stopping steroid therapy hampers early withdrawal of glucocorticoid maintenance therapy. In addition, knowledge has accumulated in diagnostic approaches including differential diagnosis of anti-neutrophil cytoplasmic antibodies-associated vasculitis, idiopathic multicentric Castleman's disease, and Rosai-Dorfman disease with kidney lesion, which leads to earlier and precise diagnosis of IgG4-RKD. This review summarizes recent progress in the differential diagnosis of IgG4-RKD and related treatment strategies and recent topics of hypocomplementaemia, membranous glomerulonephritis, and IgG4-related pyelitis and periureteral lesion.

Case report: Importance of early and continuous tocilizumab therapy in nephrotic syndrome associated with idiopathic multicentric Castleman disease: A case series

Idiopathic multicentric Castleman disease (iMCD) is a systemic and polyclonal lymphoproliferative disease involving multiple organs, including the kidneys, due to the overproduction of interleukin-6 (IL-6). Recently, several reports have suggested that excessive IL-6 actions in iMCD could have a causal relationship with the development of diverse histopathological renal manifestations that cause nephrotic syndrome. However, the treatment for such cases remains unclear. We report a series of three cases of nephrotic syndrome due to iMCD that helps to delineate the importance of early and continuous therapy with the anti-interleukin-6 receptor antibody tocilizumab. First, treatment was suspended for infectious control, and the patient presented with nephrotic syndrome due to diffuse mesangial and endocapillary hypercellularity without immune deposits complicating acute kidney injury. Second, iMCD was treated with prednisolone alone. The patient suddenly developed nephrotic syndrome due to immune-complex glomerulonephritis, not otherwise specified, complicated with acute kidney injury. In the third case, nephrotic syndrome secondary to membranous glomerulonephritis was diagnosed, with a skin rash and IgE antibodies to tocilizumab, and was therefore treated with prednisolone alone. In contrast to the first two cases, the third progressed to end-stage renal disease on hemodialysis. Taken together, this series suggests that clinicians should maintain clinical vigilance for iMCD as a possible underlying component of nephrotic syndrome, since iMCD presents with a variety of renal pathologies. Prompt initiation and continuous administration of tocilizumab are likely key determinants of renal outcomes in such cases. In particular, when tocilizumab is suspended due to infection or in the perioperative period, consideration of its expeditious resumption should be made, taking into account both the withdrawal period and systemic conditions.

A Case of Castleman's Disease during the Long-Term Course of Membranous Nephropathy

Concomitant with nephrotic syndrome and multicentric castleman's disease (MCD) has only been described in a limited number of small studies and case reports. Among those, none confirmed the renal pathology prior to the onset of MCD, and none of the cases had a history of nephrotic syndrome. A 76 year-old Japanese man visited a nephrologist because of incident nephrotic syndrome. He had previously experienced three episodes of nephrotic syndrome, the last one 13 years ago, and had been diagnosed with membranous nephropathy by renal biopsy. Apart from these previous episodes, he also suffered from systemic lymphadenopathy, anemia, elevated C-reactive protein, polyclonal hypergammopathy, and elevated interleukin (IL)-6. An inguinal lymph node biopsy revealed CD138-positive plasma cells in the interfollicular region. Based on these findings, MCD was diagnosed. Renal biopsy indicated primary membranous nephropathy with spike lesions and bubbling in the basement membranes and deposition of immunoglobulin (Ig) G, IgA, IgM, and phospholipase A2 receptor along the glomerular basement membrane. Corticosteroid monotherapy successfully reduced the edema, proteinuria, and IL-6, but hypoalbuminemia was not sufficiently improved due to castleman's disease and remission of the nephrotic syndrome was not achieved. Later, tocilizumab was administered for remission induction in another facility. To the best of our knowledge, this represents the first report of Castleman's disease with previously diagnosed membranous nephropathy. This case does not provide a causal mechanism for the pathophysiology, but it may be worth suggesting possible involvement of MCD as a trigger for recurrence of membranous nephropathy.

Multicentric Castleman Disease: The Hyaline Vascular Type Without HIV Association in a Young Male With Cutaneous Manifestation and Renal Impairment

Castleman disease (CD), a heterogenous lymphoproliferative disorder resulting from immune dysregulation, is a very rare disease in clinical practice. The clinical spectrum of Castleman disease is wide and its treatment options are mostly based on case reports and case series. To date, two clinical and four histological types have been described. It has recently been successfully demonstrated that the pathogenesis of multicentric Castleman disease (MCD) has a direct association with human immunodeficiency virus (HIV) and human herpes virus 8 (HHV-8) infection which is why further studies are necessary. Here, we report an unusual case of MCD not associated with HIV and having a histological diagnosis of the hyaline vascular type that presented with acute renal impairment and subcutaneous abnormal lymphatic proliferation.

Idiopathic multicentric Castleman disease and associated autoimmune and autoinflammatory conditions: practical guidance for diagnosis

Idiopathic multicentric Castleman disease (iMCD) is an infrequent and life-threatening disorder characterised by systemic inflammatory symptoms, generalised lymphadenopathy, polyclonal lymphocyte proliferation, and organ dysfunction caused by a hyperinflammatory state. It accounts for one third to one half of all multicentric Castleman disease (MCD) cases. iMCD is often associated with autoimmune manifestations that may precede the iMCD diagnosis, be identified at the same time or follow it. In addition, iMCD may also coincide with a number of autoimmune diseases (such as psoriasis or myasthenia gravis) or autoinflammatory diseases (such as familial Mediterranean fever). Moreover, diverse inflammatory disorders, such as rheumatoid arthritis, systemic lupus erythematosus, adult-onset Still disease, systemic juvenile idiopathic arthritis, immunoglobulin (IgG4) related disease, or the recently described VEXAS syndrome, can present clinical features or lymphadenopathy with histopathological "Castleman-like" findings compatible with those of iMCD. Given the iMCD clinical heterogeneity and the overlap with other autoimmune or autoinflammatory disorders, iMCD diagnosis can be challenging. In this review, we explore the overlap between iMCD and inflammatory diseases and provide practical guidance on iMCD diagnosis in order to avoid misdiagnosis and confusion with other autoimmune or autoinflammatory conditions.

Membranous nephropathy associated with multicentric Castleman's disease that was successfully treated with tocilizumab: a case report and review of the literature

Background

Multicentric Castleman’s disease is a life-threatening disorder involving a systemic inflammatory response and multiple organ failure caused by the overproduction of interleukin-6. Although renal complications of Castleman’s disease include AA amyloidosis, thrombotic microangiopathy, and membranoproliferative glomerulonephritis, membranous nephropathy is relatively rare. We experienced a case of secondary membranous nephropathy associated with Castleman’s disease.

Case presentation

The patient was a 43-year-old Japanese man who had shown a high zinc sulfate value in turbidity test, polyclonal hypergammaglobulinemia, anemia, and proteinuria. A physical examination revealed diffuse lymphadenopathy, an enlarged spleen and papulae of the body trunk. A skin biopsy of a papule on the patient’s back showed plasma cells in the perivascular area and he was diagnosed with multicentric Castleman’s disease, plasma cell variant. Kidney biopsy showed the appearance of bubbling in the glomerular basement membranes in Periodic acid methenamine silver stain and electron microscopy revealed electron dense deposits within and outside the glomerular basement membranes. Since immunofluorescence study showed predominant granular deposition of IgG1 and IgG2, he was diagnosed with secondary membranous nephropathy associated with Castleman’s disease. He was initially treated with prednisolone alone, however his biochemical abnormalities did not improve. After intravenous tocilizumab (700 mg every 2 weeks) was started, his C-reactive protein elevation, anemia, and polyclonal gammopathy improved. Furthermore, his urinary protein level declined from 1.58 g/gCr to 0.13 g/gCr. The prednisolone dose was gradually tapered, then discontinued. He has been stable without a recurrence of proteinuria for more than 6 months.

Conclusions

Tocilizumab might be a treatment option for secondary membranous nephropathy associated with Castleman’s disease.

Renal Diseases Associated with Hematologic Malignancies and Thymoma in the Absence of Renal Monoclonal Immunoglobulin Deposits

In addition to kidney diseases characterized by the precipitation and deposition of overproduced monoclonal immunoglobulin and kidney damage due to chemotherapy agents, a broad spectrum of renal lesions may be found in patients with hematologic malignancies. Glomerular diseases, in the form of paraneoplastic glomerulopathies and acute kidney injury with various degrees of proteinuria due to specific lymphomatous interstitial and/or glomerular infiltration, are two major renal complications observed in the lymphoid disorder setting. However, other hematologic neoplasms, including chronic lymphocytic leukemia, thymoma, myeloproliferative disorders, Castleman disease and hemophagocytic syndrome, have also been associated with the development of kidney lesions. These renal disorders require prompt recognition by the clinician, due to the need to implement specific treatment, depending on the chemotherapy regimen, to decrease the risk of subsequent chronic kidney disease. In the context of renal disease related to hematologic malignancies, renal biopsy remains crucial for accurate pathological diagnosis, with the aim of optimizing medical care for these patients. In this review, we provide an update on the epidemiology, clinical presentation, pathophysiological processes and diagnostic strategy for kidney diseases associated with hematologic malignancies outside the spectrum of monoclonal gammopathy of renal significance.

TAFRO Syndrome With Kidney Involvement: A Case Series of Patients With Kidney Biopsies

TAFRO (thrombocytopenia, anasarca, fever, reticulin myelofibrosis/renal insufficiency, and organomegaly) syndrome is a systemic inflammatory disease sharing some features with Castleman disease and POEMS (polyneuropathy, organomegaly, endocrinopathy, monoclonal protein, and skin changes) syndrome in relation to abnormal secretions of interleukin 6 and vascular endothelial growth factor. The kidney is a main target organ of TAFRO syndrome but the kidney histopathology associated with TAFRO syndrome is yet to be completely defined. We report 3 TAFRO syndrome cases with different clinical courses in which kidney biopsies were performed. In all 3 cases, kidney biopsies showed similar glomerular lesions of diffuse global swelling of the endothelium and expansion of subendothelial spaces, consistent with severe glomerular endothelial injury. Case 3 showed an additional finding of focal tubulointerstitial injury characterized by marked plasma cell infiltration, which was absent in the other 2 cases. Clinical symptoms in cases 1 and 2, which had lower disease severity scores of TAFRO syndrome, were effectively treated with the administration of corticosteroids or a combination of corticosteroids and cyclosporine A. Case 3, with a higher disease severity score, had an aggressive clinical course that was refractory to corticosteroids and tocilizumab; the patient ultimately died of multiple organ failure. In all 3 cases, kidney biopsy provided indications for the diagnosis process and clinical management of TAFRO syndrome.

Membranous nephropathy with thrombotic microangiopathy-like lesions successfully treated with tocilizumab in a patient with idiopathic multicentric Castleman disease

Idiopathic multicentric Castleman disease (iMCD) is a systemic lymphoproliferative disease involving multiple organs, including the kidneys. Membranous nephropathy (MN) has been rarely reported as a complication of iMCD. We herein report the case of a 48-year-old man with a 9-year history of iMCD that was complicated by treatment-resistant nephrotic syndrome due to MN. The first renal biopsy performed at the age of 45 years showed diffuse and global MN with a mild glomerular endothelial injury. He was treated with combined therapy of corticosteroids, immunosuppressants, and tocilizumab, an anti-interleukin-6 (IL-6) receptor monoclonal antibody, which was administered every 2-3 weeks. However, nephrotic syndrome persisted, and renal impairment slowly worsened. Serial biopsy performed at 3 years after the first biopsy confirmed advanced lesions of both MN-related and glomerular endothelial injuries. Modification of the therapeutic strategy to weekly administration of tocilizumab gradually led to the remission of proteinuria, allowing the termination of corticosteroids. Thus, the present case suggests a close link between excessive IL-6 actions and the development of glomerular lesions in iMCD. Successful treatment by strict inhibition of IL-6 actions, in this case, may provide a clue for deciding the therapeutic strategy for severe renal complications associated with iMCD.

Idiopathic multicentric Castleman disease with Sjögren's syndrome and secondary membranous nephropathy: a case report and review of the literature

Background

Idiopathic multicentric Castleman disease (iMCD) is an uncommon lymphoproliferative disorder and lacks treatment consensus. Herein, we report a case of iMCD complicated with Sjögren’s syndrome (SS) and secondary membranous nephropathy (SMN).

Case presentation

A 45-year-old female with dry mouth for 3 months and anasarca and proteinuria for 2 months was admitted. She also experienced chest tightness, wheezing, fever, weight loss, moderate proteinuria and hypoalbuminemia. A computed tomography (CT) scan revealed a tissue mass in the thymus area and enlarged multiple lymph nodes. Her symptoms did not improve after resection of the thymus mass. The pathological findings were “reactive hyperplasia of the mediastinal lymph nodes and thymic hyperplasia”. Lymph node biopsy findings confirmed iMCD with human herpes virus-8 (HHV-8) negativity. Based on anti-nuclear antibody (ANA) 1:320, anti-SSA and anti-SSB antibody positivity, salivary flow less than 0.1 ml/min and lip biopsy with focal lymphocytic sialadenitis, SS was diagnosed. Kidney biopsy showed secondary membranous nephropathy with endocapillary cell proliferation and infiltration of plasma cells and lymphocytes in the tubulointerstitium. Serum interleukin-6 (IL-6) levels were significantly increased, and therapy with tocilizumab (anti-IL-6 receptor antibody) worked well. The combination of cyclophosphamide (CyS) with methylprednisolone (MP) maintained satisfactory remission.

Conclusions

Our case of iMCD with SS and SMN is rare. There is a need for increased awareness of the disease to avoid unnecessary procedures and misdiagnoses. IL-6 was extremely high, and there was a rapid response to anti-IL-6 receptor agents. The combination of CyS with MP maintained complete remission.

Kidney biopsy findings in two patients with TAFRO syndrome: case presentations and review of the literature

Background

TAFRO syndrome is a clinical subtype of idiopathic multicentric Castleman disease (iMCD) that is characterized by thrombocytopenia, anasarca, fever, reticulin myelofibrosis (or renal dysfunction), and organomegaly. TAFRO syndrome has only recently been described, and many clinicians are unaware of this disease, leading to delays in diagnosis and treatment. We present two patients with TAFRO syndrome in whom renal biopsies were performed.

Case presentation

Both patients had subacute onset and exhibited renal insufficiency, edema, anemia, thrombocytopenia, polyserositis and lymphadenopathy over the disease course. However, there were many differences in their clinical manifestations. Case 1 was a 30-year-old woman admitted due to intermittent vaginal bleeding for 3 weeks. Laboratory tests on admission showed severe renal insufficiency (creatinine: 624 μmol/L), severe anemia (Hb: 41 g/L), and moderate thrombocytopenia (61 × 10⁹/L). Case 2 was a 42-year-old man. Acute epigastric pain was his initial complaint, and computed tomography (CT) revealed retroperitoneal exudation around the pancreas. He was diagnosed with acute pancreatitis, and after treatment with a proton pump inhibitor (PPI) and somatostatin, his abdominal pain still recurred. During treatment, renal failure gradually increased, with oliguria, fever, anemia, thrombocytopenia, edema and massive ascites. Lymph node histologies were consistent with the hyaline-vascular (HV) type and mixed type, respectively, and renal histopathologies were consistent with thrombotic microangiopathy (TMA)-like renal lesions and membranoproliferative glomerulonephritis (MPGN), respectively. Their general conditions improved after glucocorticoid therapy, but their renal functions did not recover completely. On the basis of glucocorticoids, second-line treatments with tocilizumab and rituximab, respectively, were applied.

Conclusions

The diagnosis of TAFRO syndrome is based mainly on clinical manifestations and lymph node biopsies. A reliable early diagnosis and appropriate rapid treatment are essential to improve patient outcomes. Clinicians should deepen their understanding of this disease and similar conditions. Once the disease is suspected, lymph node biopsies should be performed as soon as possible. In addition, renal biopsies should be actively performed in patients with renal involvement.

Five biopsies, one diagnosis: challenges in idiopathic multicentric Castleman disease

A previously healthy 29-year-old man initially presented to the hospital with pleuritic chest pain and shortness of breath. Over the next 2 months he developed ongoing fevers and night sweats with recurrent exudative pleural effusions and ascites. He had an extensive infectious and autoimmune workup that was unremarkable. He had an initial lymph node biopsy that showed reactive changes only. He had an acute kidney injury and his renal biopsy revealed thrombotic microangiopathy. His liver biopsy showed non-specific inflammatory changes. His bone marrow biopsy showed megakaryocyte hyperplasia and fibrosis, which raised suspicion for the thrombocytopenia, ascites, reticulin fibrosis, renal dysfunction and organomegaly syndrome subtype of multicentric Castleman disease. This prompted a repeat lymph node biopsy, showing changes consistent with mixed type Castleman disease that fit with his clinical picture. He was initiated on steroids and siltuximab with significant clinical improvement.

Two cases of idiopathic multicentric Castleman disease with nephrotic syndrome treated with tocilizumab

We report two cases of idiopathic multicentric Castleman disease (iMCD) with nephrotic syndrome (NS) treated with tocilizumab. Case 1 was a 58-year-old man diagnosed with iMCD prior to the onset of NS. Renal biopsy revealed membranous nephropathy, which was considered to be secondary membranous nephropathy associated with iMCD. Case 2 was a 49-year-old woman diagnosed with iMCD prior to NS. Renal biopsy revealed renal amyloidosis positive for Congo red staining and amyloid A protein immunostaining. In both the cases, the proteinuria improved after the initiation of glucocorticoid and tocilizumab therapy. Tocilizumab may be a good therapeutic choice for iMCD with NS.

Acute Kidney Injury Caused by TAFRO Syndrome in a Chinese Patient: Efficacy of Long-Term Corticosteroids Combined with Bortezomib and Cyclophosphamide

INTRODUCTION

Thrombocytopenia, ascites, myelofibrosis, renal dysfunction, and organomegaly (TAFRO) syndrome is a newly recognized and rare clinical subtype of Castleman disease. Renal involvement in TAFRO syndrome usually presents with mild proteinuria, microscopic hematuria, and acute renal injury requiring temporary renal replacement. There is no standard therapy available and treatment failures are common, leading to a poor prognosis. We report a case of acute renal failure caused by TAFRO syndrome, successfully managed by long-term corticosteroids combined with bortezomib and cyclophosphamide.

CASE PRESENTATION

The patient was a 52-year-old female who presented with fever, anasarca, oliguria, and abdominal distension at first. She progressed rapidly to anuric renal failure requiring hemodialysis. She also demonstrated thrombocytopenia, anemia, coagulopathy, and a hyperinflammatory status. Her CT scan showed severe polyserositis, splenomegaly, and lymphadenopathy. Her serum vascular epithelial growth factor level was significantly elevated. Axillary lymph node biopsy showed hyaline-vascular type Castleman disease, supporting the diagnosis of TAFRO syndrome. Her renal function recovered after high-dose steroids and supportive treatment. A weekly dosing regimen of bortezomib, cyclophosphamide, and dexamethasone combined with medium dose prednisone in between were deployed. Her blood cell count and renal function remained stable after 6 months. The inflammation was suppressed and the polyserositis resolved completely.

CONCLUSION

TAFRO syndrome is rare and has a poor prognosis due to the lack of standard treatment. Our patient might be the first TAFRO case successfully treated by bortezomib, cyclophosphamide, and corticosteroids.

Retrospective analysis of 45 cases of localized retroperitoneal Castleman disease from a single center

Background

Castleman disease (CD) is a rare lymphoproliferative disease characterized by high heterogeneity in clinical manifestation and prognosis. This study aimed to summarize clinical features of localized retroperitoneal CD and our experiences to improve the diagnosis and treatment of this disease.

Methods

Clinical data of 45 patients with localized retroperitoneal CD were retrospectively analyzed. The differences in clinical features between groups with and without paraneoplastic pemphigus (PNP) were compared. Survival was analyzed between groups depending on whether complicating with PNP, bronchiolitis obliterans (BO), gender, age and uni-centric CD (UCD)/multi-centric CD (MCD), respectively.

Results

Significant differences were observed between patient groups in the prevalence of retroperitoneal CD with PNP complicated with BO (P=0.010), the constituent ratios of initial symptoms (P<0.001) and the duration from appearance of the initial symptoms to being diagnosed (P=0.009). Among 45 cases, 43 tumors had clear margins and intact envelops and were completely resected, 40 patients were cured or significantly relieved, 3 patients were not significantly relieved, 2 patients received palliative surgical therapy and eventually relapsed and died after surgery. There were significant differences in the survival rate between groups depending on complication with BO, gender and age (≤40 and >40 years) (all P<0.05).

Conclusions

Prompt and complete removal of the retroperitoneal CD tumor is critical to the management of this disease, as palliative resection tends to cause relapse and lead to a poor prognosis. Retroperitoneal CD patients with PNP may develop complications from BO leading to death. Complication with PNP, complication with BO, male gender and age ≥40 years were identified as prognostic risk factors for patients with localized retroperitoneal CD.

HHV-8-negative multicentric Castleman disease presenting as a crescentic immune complexes membranoproliferative glomerulonephritis

Multicentric Castleman disease is a rare polyclonal lymphoproliferative disorder mainly associated with two renal manifestations: thrombotic microangiopathy and amyloidosis. Nevertheless, we report here a case of human herpes virus-8 negative multicentric Castleman disease with membranous proliferative glomerulonephritis and extracapillary proliferation. A patient was successfully treated with corticosteroids, anti-CD20 and cyclophosphamide therapy.

Association of vascular endothelial growth factor and renal thrombotic microangiopathy-like lesions in patients with Castleman's disease

AIM

Renal thrombotic microangiopathy (TMA) is a common pathological manifestation of Castleman's disease (CD)-associated renal lesions. Increased level of plasma vascular endothelial growth factor (VEGF) has been shown in single-case reports. We aimed to investigate the dysregulation of VEGF in the pathogenesis of CD-associated TMA-like lesions (CD-TMA) in a larger cohort.

METHODS

Nineteen patients with clinico-pathologically diagnosed CD with renal involvement were enrolled. Ten patients with pregnancy TMA or TMA of unknown reasons were enrolled as TMA control group. The plasma levels of VEGF, soluble Flt-1 and interleukin-6 (IL-6) were detected using enzyme-linked immunosorbent assay kits. The expression of VEGF in the kidney biopsied tissue sections and the lymph node specimens were detected by immunostaining.

RESULTS

The plasma levels of VEGF and IL-6 levels were the highest in CD-TMA group compared to TMA control group and healthy controls. The levels of plasma VEGF was positively correlated with that of IL-6, and increased expression of VEGF and IL-6 was also observed in the lymph nodes from CD-TMA patients. However, the expression of VEGF in the glomerular podocytes was significantly decreased in CD-TMA group as well as in the TMA control.

CONCLUSION

Our findings suggest that renal VEGF expression might be important in the pathogenetic mechanism of CD-associated TMA-like lesions.

The efficacy and safety of anti-interleukin-6 receptor monoclonal blockade in a renal transplant patient with Castleman disease: early post-transplant outcome

Background

Multicentric Castleman disease (MCD) is an uncommon lymphoproliferative disease characterized by systemic inflammatory reactions associated with the dysregulated production of interleukin-6 (IL-6). In patients with MCD, renal involvement is uncommon, with only one report published regarding kidney transplantation (KTx) to treat end-stage renal disease (ESRD) secondary to MCD. Recent clinical observations have shown that IL-6 production is implicated in allograft rejection, while IL-6 receptor blockade (with tocilizumab [TCZ]) reduces alloantibody generation and thereby improves graft survival; however, the efficacy and safety of TCZ in MCD patients undergoing KTx is still unknown.

Case presentation

Herein, we describe the case of a 50-year-old man with MCD who received living-donor KTx for ESRD. Post-operative immunosuppression consisted of a triple-drug regimen (tacrolimus, mycophenolate mofetil and methylprednisolone) with TCZ that was administered intravenously every 2 weeks. At 17 months post-transplantation, the patient remains asymptomatic, and the allograft pathology has shown no evidence of rejection and no development of de novo donor-specific antibody (DSA).

Conclusions

To our knowledge, this is the second reported case of an MCD patient with ESRD who underwent successful KTx. TCZ safely supported the patient during the perioperative period, and this drug may be useful for blocking the generation of donor-specific antibodies and reducing the risk of rejection episodes. KTx in combination with TCZ is thus considered a viable treatment option for ESRD due to MCD.

An autopsy case of TAFRO syndrome with membranoproliferative glomerulonephritis-like lesions

TAFRO syndrome (thrombocytopenia, anasarca, myelofibrosis, renal dysfunction, and organomegaly) is an atypical manifestation of multicentric Castleman's disease. Although overproduction of interleukin-6, vascular endothelial growth factor, and other cytokines may partially explain the pathophysiology of this rare syndrome, the precise mechanisms underlying the renal dysfunction associated with the condition remain unclear. Here, we describe a case of a 69-year-old male with TAFRO syndrome. He was treated with immunosuppressive agents and his renal function improved. Tapering of immunosuppressive agents resulted in a deterioration of renal function and an elevation of C-reactive protein. After 20 months of treatment, the patient died from tuberculous peritonitis and gastrointestinal bleeding. An autopsy revealed miliary tuberculosis, mediastinal lymphadenopathy, and gastric ulcers. Renal histopathology showed a membranoproliferative glomerulonephritis-like appearance. Almost all glomeruli showed lobular formations with mesangial proliferation and duplication of glomerular capillary walls on light microscopy. Immunofluorescence showed deposition of C1q and IgM along the glomerular capillary walls. Electron microscopy showed mesangial expansion and widening of the subendothelial space with a large number of electron-dense deposits. The glomerular lesions might be characteristic of TAFRO syndrome, and were regarded as the main cause of the patient's renal dysfunction.

Renal failure in pediatric Castleman disease: Four French cases with thrombotic microangiopathy

Pediatric Castleman disease (CD) is an uncommon and poorly understood disorder of the lymph nodes. Renal failure has not been described in pediatric multicentric CD (MCD). We report four cases, who presented with polyadenopathy, organomegaly, edema and fluid accumulations, high blood pressure, and acute renal failure. In all cases, renal biopsy confirmed diffuse thrombotic microangiopathy. Definitive diagnosis of MCD was made by a biopsy of an affected lymph node located by computer tomography before initiation of corticosteroid therapy. Treatment of CD with corticosteroid therapy and rituximab was rapidly effective without relapse to date.

Membranoproliferative glomerulonephritis-like findings for TAFRO syndrome, associated with an anterior mediastinal tumor: A case report

RATIONALE

TAFRO syndrome is a systemic inflammatory disease proposed recently from Japan. The cause of TAFRO syndrome is unclear. Moreover, the disease characteristics and kidney pathology are yet unknown well and there are few cases. Herein, we report a patient with TAFRO syndrome and present the features of the renal histopathology.

PATIENT CONCERNS

A 55-year-old woman presented to our hospital with the main complaint of subacute dyspnoea.

DIAGNOSIS

Physical findings included a low-grade fever and generalised oedema. A blood test showed anaemia, coagulation abnormalities, hypoproteinaemia, impaired renal function, proteinuria, and elevated alkaline phosphatase (ALP), C-reactive protein (CRP), interleukin-6 (IL-6). Chest and abdominal computed tomography showed an anterior mediastinal mass and multiple enlarged lymph nodes.

INTERVENTIONS

Nephrotic syndrome secondary to a malignant mediastinal tumour was suspected; therefore, the patient underwent resection of the anterior mediastinal mass. Histopathological examination of the resected specimen showed lymphocytic proliferation without signs of malignancy. These findings were compatible with hyaline vascular type Castleman disease (CD), and with the associated multiple lymph nodes enlargement, the patient was initially diagnosed with multicenteric CD.

OUTCOMES

After resection of the whole tumour, all the clinical symptoms improved. However, after resection 6 months passed, the patient developed thrombocytopenia, anaemia, renal dysfunction, further enlargement of the residual lymph nodes, hepatosplenomegaly, and mild myelofibrosis. A diagnosis of TAFRO syndrome (TS) was eventually made. All symptoms improved with initial intravenous pulse steroid therapy followed by oral steroids. Histopathological examination of the renal biopsy samples showed findings resembling membranoproliferative glomerulonephritis (MPGN).

LESSONS

In TS, all characteristic signs may not exist from the beginning. The association between TS and CD is not clear. When we compared our findings with previously published cases of TS and CD, we found that the renal pathology findings resembled MPGN in many cases of TS, while only a few cases showed amyloidosis. Recent results suggest that TS may be an independent disease from CD, and given the frequency of renal pathology findings, it may also have a different aetiology. To the best of our knowledge, this case report is rare to demonstrate the renal pathology in a patient with conventional TAFRO syndrome.

Thrombotic microangiopathy on kidney biopsy in a patient with TAFRO syndrome

TAFRO syndrome represents a characteristic constellation of symptoms comprising Thrombocytopenia, Anasarca, myeloFibrosis, Renal dysfunction, and Organomegaly, and is considered to be a clinicopathologic variant of idiopathic multicentric Castleman disease. A 51-year-old woman was admitted to the hospital complaining of abdominal distension. Findings on physical examination were indicative of anasarca. Computed tomography revealed mild splenomegaly, pericardial effusion, pleural effusion, ascites, and paraaortic lymphadenopathy. Blood tests showed thrombocytopenia, and urinalysis demonstrated hematuria, proteinuria, and worsening renal function. Kidney biopsy was performed and revealed thrombotic microangiopathy-like lesions with global sclerosis of 1 of the 16 glomeruli on light microscopy. The remaining glomeruli had a distinct lobular pattern, with mesangiolysis, double contours of the glomerular basement membranes, and marked endothelial swelling. Immunofluorescence studies for IgG, IgM, IgA, C1q, C3, C4, κ-light chains, and λ-light chains were indeterminate. Electron microscopy showed marked endothelial swelling. We made a diagnosis of TAFRO syndrome and started steroid treatment, following which her symptoms gradually improved. There are few reports describing renal pathology in a patient with TAFRO syndrome.

Effectiveness of rituximab-containing treatment regimens in idiopathic multicentric Castleman disease

Human herpes virus type 8 (HHV-8)-negative, idiopathic multicentric Castleman disease (iMCD) is a rare lymphoproliferative disease often involving constitutional symptoms, cytopenias, and multiple organ system dysfunction. In China, the majority of MCD cases are HHV-8 negative. Given that siltuximab, the only FDA-approved treatment for iMCD is not available in China; rituximab- and cyclophosphamide-containing regimens are often used in the treatment of Chinese iMCD patients. To evaluate the efficacy of rituximab in this rare and heterogeneous disease, clinical and pathological data from 27 cases of iMCD were retrospectively analyzed from two large medical centers in China. The novel diagnostic criteria for iMCD were applied, and POEMS syndrome, IgG4-related diseases, and follicular dendritic cell sarcomas cases were excluded from analyses. Total response rate of rituximab- and cyclophosphamide-containing regimens was 55.5%, with 33.3% (9/27) of the cases reaching CR and 22.2% (6/27) PR. In the 14 cases of R-R iMCD, total response rate was only 42.9% (CR 14.3% [2/14], PR 28.6% [4/14]). The 5-year OS of these 27 iMCD cases was 81% (95% CI 64-98; 27 total patients, 4 events, 23 censored) after receiving these regimens, but the 5-year PFS was 43% (95% CI 19-66; 25 total patients, 11 events, 14 censored). Thus, rituximab-based regimens should be considered for the treatment of iMCD patients when siltuximab is not available and potentially in siltuximab-refractory cases.

Nephrotic Syndrome with Thrombocytopenia, Lymphadenopathy, Systemic Inflammation, and Splenomegaly

Nephrotic syndrome can be caused by various diseases, from primary kidney diseases to systemic diseases. A kidney biopsy is useful for confirming the causes of nephrotic syndrome and in its management. We herein describe a case of nephrotic syndrome with thrombocytopenia, lymphadenopathy, systemic inflammation, splenomegaly, kidney enlargement, and progressive renal insufficiency. A kidney biopsy showed endothelial swelling with mild interstitial fibrosis and tubular atrophy. This case met the diagnostic criteria for TAFRO syndrome. Little is known about TAFRO syndrome, especially in relation to the associated kidney pathophysiology. The accumulation of a greater number of cases in which the kidney biopsy findings are investigated is needed to clarify the pathogenesis of kidney involvement in this condition.

Severe refractory TAFRO syndrome requiring continuous renal replacement therapy complicated with Trichosporon asahii infection in the lungs and myocardial infarction: an autopsy case report and literature review

Background

TAFRO (thrombocytopenia, anasarca, fever, reticulin myelofibrosis/renal failure, and organomegaly) syndrome is a systemic inflammatory disorder and unique clinicopathological variant of idiopathic multicentric Castleman disease that was proposed in Japan. Prompt diagnosis is critical because TAFRO syndrome is a progressive and life threating disease. Some cases are refractory to immunosuppressive treatments. Renal impairment is frequently observed in patients with TAFRO syndrome, and some severe cases require hemodialysis. Histological evaluation is important to understand the pathophysiology of TAFRO syndrome. However, systemic histopathological evaluation through autopsy in TAFRO syndrome has been rarely reported previously.

Case presentation

A 46-year-old Japanese man with chief complaints of fever and abdominal distension was diagnosed with TAFRO syndrome through imaging studies, laboratory findings, and pathological findings on cervical lymph node and bone marrow biopsies. Interleukin (IL)-6 and vascular endothelial growth factor (VEGF) levels were remarkably elevated in both blood and ascites. Methylprednisolone (mPSL) pulse therapy was initiated on day 10, followed by combination therapy with PSL and cyclosporine A. However, the amount of ascites did not respond to the treatment. The patient became anuric, and continuous renal replacement therapy was initiated from day 50. However, the patient suddenly experienced cardiac arrest associated with myocardial infarction (MI) on the same day. Although the emergent percutaneous coronary intervention was successfully performed, the patient died on day 52, despite intensive care. Autopsy was performed to ascertain the cause of MI and to identify the histopathological characteristics of TAFRO syndrome.

Conclusions

Bacterial peritonitis, systemic cytomegalovirus infection, and Trichosporon asahii infection in the lungs were observed on autopsy. In addition, sepsis-related myocardial calcification was suspected. Management of infectious diseases is critical to reduce mortality in patients with TAFRO syndrome. Although the exact cause of MI could not be identified on autopsy, we considered embolization by fungal hyphae as a possible cause. Endothelial injury possibly caused by excessive secretion of IL-6 and VEGF contributed to renal impairment. Fibrotic changes in anterior mediastinal fat tissue could be a characteristic pathological finding in patients with TAFRO syndrome.

The Clinical and Immunologic Features of Patients With Combined Anti-GBM Disease and Castleman Disease

Patients with both anti-glomerular basement membrane (anti-GBM) disease and Castleman disease have been rarely reported. In this study, we report 3 patients with this combination. They had immunologic features similar to patients with classic anti-GBM disease. Sera from the 3 patients recognized the noncollagenous (NC) domain of the α3 chain of type IV collagen (α3(IV)NC1) and its 2 major epitopes, EA and EB. All 4 immunogloblin G (IgG) subclasses against α3(IV)NC1 were detectable, with predominance of IgG1. In one patient with lymph node biopsy specimens available, sporadic plasma cells producing α3(IV)NC1-IgG were found, suggesting a causal relationship between the 2 diseases. One patient, who achieved remission with antibody clearance and normalization of serum creatinine and interleukin 6 concentrations after plasma exchange and 3 cycles of chemotherapy, experienced recurrence of anti-GBM antibodies and an increase in interleukin 6 concentration after chemotherapy discontinuation because of adverse effects, but both returned to normal after another cycle of chemotherapy. This clinical course and the pathologic findings support the hypothesis that the Castleman disease-associated tumor cells are the source of the anti-GBM autoantibodies.

Diagnosis of Castleman Disease

Castleman disease (CD) is a rare and heterogenous group of disorders sharing in common an abnormal lymph node pathology. CD comprises distinct subtypes with different prognoses. Unicentric CD and multicentric CD are featured by specific systemic manifestations and may be associated with Kaposi sarcoma, non-Hodgkin and Hodgkin lymphoma, and POEMS syndrome. Multicentric CD is classically associated with systemic symptoms and poorer prognosis. In this article, the authors review how to diagnose the disease, keeping in context the clinical findings, biochemical changes and complications associated with CD.

Clinicopathological features of progressive renal involvement in TAFRO syndrome: A case report and literature review

RATIONALE

TAFRO syndrome is a systemic inflammatory disease characterized by a constellation of symptoms: Thrombocytopenia, Anasarca, MyeloFibrosis, Renal dysfunction, and Organomegaly. Progressive renal insufficiency is a predominant symptom; however, the mechanism of acute kidney injury (AKI) remains unclear, probably because severe thrombocytopenia prevents kidney biopsy. We report a rare case of TAFRO syndrome with histologically confirmed renal involvement.

PATIENTS CONCERNS

A 70-year-old man developed fever, anasarca, AKI, thrombocytopenia, and hepatosplenomegaly.

DIAGNOSES

Plasma vascular endothelial growth factor and serum interleukin-6 levels were significantly elevated. The diagnosis of TAFRO syndrome was made based on his clinical and laboratory findings. Kidney biopsy was performed for the evaluation of AKI and provided a diagnosis of membranoproliferative glomerulonephritis-like lesions due to endothelial injury. Glomerular capillary lumens were extremely narrowed or occluded by endothelial swelling, and marked widening of the subendothelial space by electron-lucent material resulted in mesangiolysis and a double-contoured glomerular basement membrane with no immune complex deposits.

INTERVENTIONS AND OUTCOMES

The patient required temporary hemodialysis due to oliguric AKI, but steroid therapy rapidly improved renal function.

LESSONS

Typically, patients with progressive renal involvement in TAFRO syndrome rapidly develop oliguric or anuric AKI. This report suggests that the reduction of glomerular perfusion by glomerular endothelial injury might be a primary factor in the progressive AKI of TAFRO syndrome. Our case and the literature review indicate that steroid and/or biological therapies result in highly favorable renal outcomes in patients with progressive AKI in TAFRO syndrome.

TAFRO Syndrome in Caucasians: A Case Report and Review of the Literature

Background

TAFRO syndrome has been reported in Japan among human herpesvirus 8 (HHV-8)-negative/idiopathic multicentric Castleman’s disease (iMCD) patients. To date, the majority of iMCD patients with TAFRO syndrome originate from Japan.

Case presentation

Herein, we report a 67-year-old HIV/HHV-8-negative Caucasian iMCD patient diagnosed with TAFRO. He presented with marked systemic inflammation, bicytopenia, terminal renal insufficiency, diffuse lymphadenopathies, and anasarca. Lymph node and bone marrow biopsies revealed atrophic germinal centers variably hyalinized and megakaryocytic hyperplasia with mild myelofibrosis. Several other biopsies performed in kidneys, liver, gastrointestinal tract, prostate, and lungs revealed unspecific chronic inflammation. The patient had a complete response to corticosteroids, tocilizumab, and rituximab. He relapsed twice following discontinuation of rituximab. When reviewing the literature, we found seven other Caucasian cases with TAFRO syndrome. There were no significant differences with those described by the Japanese cohort except for the higher frequency of kidney failure and auto-antibodies in Western patients.

Conclusion

This case illustrates that patients with TAFRO syndrome can develop non-specific inflammation in several tissue sites. Furthermore, this case and our review of the literature demonstrate that TAFRO syndrome can affect Caucasian and Japanese patients highlighting the importance of evaluating for this syndrome independently of ethnic background.

Focal segmental glomerulosclerosis associated with cutaneous and systemic plasmacytosis

Cutaneous and systemic plasmacytosis (CSP) is a rare lymphoproliferative disorder that mainly affects middle-aged Asian individuals. Although Castleman disease is often complicated with various renal involvements, glomerulonephritis associated with CSP, which is considered as a variant of Castleman disease, is rare. This report presents the case of a 41-year-old Japanese man with nephrotic syndrome associated with CSP. Renal biopsy findings showed focal segmental glomerulosclerosis (FSGS) and diffusely mild segmental mesangial proliferation. Plasma cell infiltration in the interstitium was not observed. Electron microscopic findings showed diffuse foot process effacement, localized involvement of subendothelial space widening with amorphous materials, and endothelial cell swelling. Lymph node biopsy findings denied Castleman disease. His skin regions and proteinuria were successfully treated with prednisolone and cyclosporine. The causal relationship between CSP and FSGS is unknown. However, increased serum levels of IL-6 and VEGF and decreased VEGF expression in the podocyte may contribute to renal lesions in patients with CSP. To our best knowledge, this is the first case of a patient with FSGS associated with CSP.

Castleman Disease of the Thorax: Clinical, Radiologic, and Pathologic Correlation: From the Radiologic Pathology Archives

Castleman disease is a complex lymphoproliferative disease pathologically divided into two subtypes, the hyaline vascular variant (HVV) and the plasma cell variant (PCV). The HVV is the most common, is thought to represent a benign neoplasm of lymph node stromal cells, and is treated with surgical resection. It is most commonly found in the mediastinum, where it classically appears as a unicentric, avidly enhancing mass at computed tomography (CT) and magnetic resonance imaging. This appearance can mimic other avidly enhancing mediastinal masses, and location, clinical history, laboratory data, and nuclear medicine single photon emission CT (SPECT) and positron emission tomography (PET) studies can help narrow the differential diagnosis. Multicentric Castleman disease (MCD), which in the majority of cases is composed of the PCV, is an aggressive lymphoproliferative disorder associated with human herpesvirus infection, interleukin 6 dysregulation, and other systemic disorders. While it can be difficult to differentiate MCD from lymphoma, the presence of avidly enhancing lymph nodes can suggest the diagnosis. The purpose of this article is to review the clinical, immunologic, and pathologic findings associated with both unicentric Castleman disease and MCD and discuss how the imaging findings correlate with the pathophysiology of the disease.

Unicentric Castleman’s disease associated with end stage renal disease caused by amyloidosis

Castleman’s disease (CD), also known as angiofolicular lymph node hyperplasia, is a rare heterogenous group of lymphoproliferative disorders. Histologically, it can be classified as hyaline vascular type, plasma cell type, or mixed type. Clinically two different subtypes of the CD are present: Unicentric and multicentric. Unicentric CD is generally asymptomatic and associated with hyaline vascular type, and its diagnoses depend on the localized lymphadenopathy on examination or imaging studies. However, multicentric CD presents with generalized lymphadenopathy and systemic symptoms including malaise, fever, night sweats, weight loss, and it is associated with the plasma cell type and mix type. Herein, we report a patient with unicentric CD of the plasma cell type without systemic symptoms, who developed end stage renal failure caused by amyloidosis 6 years after onset of CD.

Successful treatment by tocilizumab without steroid in a very severe case of TAFRO syndrome

Successful use of tocilizumab (TCZ) to treat TAFRO syndrome has recently been reported. In those cases, TCZ was used with steroid. We present herein the case of a 59-year-old man with very severe TAFRO syndrome who was successfully treated using TCZ without steroid. He showed rapidly progressive anasarca, acute renal failure and very severe thrombocytopenia. We initially used steroid, but its efficacy was limited. Moreover, steroid use had to be stopped as soon as possible, because hemorrhagic shock developed due to severe duodenal ulcer. After overcoming infections (about 40 days after stopping steroid), administration of TCZ was started and the patient was discharged in clinical remission.

A rare case of renal thrombotic microangiopathy associated with Castleman's disease

Background

Castleman’s disease (CD) is an uncommon, heterogeneous lympho-proliferative disorder leading to high circulating levels of interleukin-6 (IL-6) and vascular endothelial growth factor (VEGF). Renal involvement has been only described in a limited number of small studies. Herein, we report a rare case of renal thrombotic microangiopathy (TMA) associated with CD and investigate the podocyte expression of VEGF in the renal biopsy prior to initiation of treatment.

Case presentation

An 18-year-old male presented with fever, diarrhea, diffuse lymphadenopathy, ascites and acute kidney injury. Laboratory tests for hemolytic uremic syndrome and thrombotic thrombocytopenic purpura were negative. The kidney biopsy showed TMA. An excisional lymph node biopsy was consistent with CD, plasma cell variant. Immunofluorescence staining showed suppressed podocyte VEGF expression. Chemotherapy that inhibits production of inflammatory mediators including IL-6 and VEGF led to complete recovery of renal function.

Conclusions

Our case illustrates a rare renal histological feature of CD. IL-6 and VEGF are postulated to suppress glomerular VEGF expression, thereby causing renal TMA. Therapy directed against these inflammatory mediators may have important therapeutic implications.

Magnetic resonance imaging of bone marrow for TAFRO syndrome

We report two cases of TAFRO syndrome, which is characterized by thrombocytopenia, anasarca, fever, renal insufficiency, and organomegaly. Magnetic resonance imaging (MRI) of the spine showed a dark medullary pattern in the bone marrow on the T1- and T2-weighted images of both patients. One patient showed complete resolution after treatment. Serial MRIs of the improved patient revealed a transition to a normal marrow pattern on both images, which might represent resolution of the disease.

Case report and literature review: Glomerular and neurologic thrombotic microangiopathy as a primary manifestation of multicentric castleman disease

INTRODUCTION

We report the case of a multicentric Castleman disease (MCD) with initial renal involvement. Although the renal involvement in this case was typical of MCD, it constitutes a rare presentation of the disease, and in our case the renal manifestations led to the haematological diagnosis.

CLINICAL FINDINGS/PATIENT CONCERNS

The patient was admitted for fever, diarrhea, anasarca, lymphadenopathies and acute renal failure. Despite intravenous rehydration using saline and albumin, renal function worsened and the patient required dialysis. While diagnostic investigations were performed, right hemiplegia occurred. There was no anemia or thrombocytopenia.

DIAGNOSES

Kidney biopsy was consistent with glomerular thrombotic microangiopathy (TMA). Lymph node histology was consistent with hyalin-vascular variant of Castleman disease.

OUTCOMES

Given the renal and neurological manifestations of this MCD-associated TMA, the patient was treated with plasma exchange during one month, and six courses of rituximab, cyclophosphamide and dexamethasone. The evolution was favorable.

CONCLUSION

Although rare, this diagnosis is worth knowing, as specific treatment has to be started as soon as possible and proved to be efficient in our case as well as in other reports in the literature.

Multicentric Castleman Disease With Tubulointerstitial Nephritis Mimicking IgG4-related Disease: Two Case Reports

Multicentric Castleman disease is a benign lymphoproliferative disorder with heterogenous clinical symptoms and involves systemic organs in addition to lymph nodes. Elevated serum IgG4 levels and IgG4-positive plasma cell (IgG4+PC) infiltrates have been reported in lymph nodes, lung and skin in some multicentric Castleman disease cases, resembling IgG4-related disease (IgG4-RD) histologically. However, no report has been available regarding IgG4+PC infiltration in the kidneys of multicentric Castleman disease. Here, we report 2 cases of multicentric Castleman disease complicated by IgG4-related disease (IgG4-RD) histologically. However, there has been no report published on PC-rich tubulointerstitial nephritis, lymphadenopathy, with numerous IgG4+PC infiltration, and elevated serum IgG4 levels, mimicking IgG4-RD. The blood examinations revealed systemic inflammation and elevated C-reactive protein and interleukin-6 levels. Corticosteroid therapy was partially effective in both cases, and combination therapy of corticosteroid and tocilizumab was needed in both cases. Moreover, after triple therapy with corticosteroid, rituximab and cyclophosphamide were used in 1 case to tame the severe inflammation. The present cases suggest that if continuously elevated serum C-reactive protein levels and partial corticosteroid responsiveness are encountered, multicentric Castleman disease should be considered rather than IgG4-RD as a differential diagnosis even if serum IgG4 is elevated and IgG4+PCs infiltrate systemic organs.

Plasmapheresis Is Associated With Better Renal Outcomes in Lupus Nephritis Patients With Thrombotic Microangiopathy: A Case Series Study

The aim of this study was to evaluate the efficacy of plasmapheresis in patients with lupus nephritis-combined thrombotic microangiopathy (TMA) in a Chinese cohort.Clinical and therapeutic data of patients with lupus nephritis-combined TMA were collected retrospectively. A comparison between those with and without plasmapheresis was performed.Seventy patients with renal biopsy-proven TMA in lupus nephritis were treated with conventional combined corticosteroid and immunosuppressive agents as induction therapy, 9 of the 70 patients received additional plasmapheresis. The plasmapheresis group presented with more severe SLE and renal activity indices, including a significant higher ratio of neurologic disorder (P = 0.025), lower level of platelet count (P = 0.009), higher value of serum creatinine (P = 0.038), higher percentage of anti-cardiolipin antibodies positive (P = 0.001), and higher Systemic Lupus Erythematosus Disease Activity Index scores (P = 0.012), than that of the nonplasmapheresis group. However, the plasmapheresis group had a significant higher rate of remission and a lower ratio of treatment failure than that of the nonplasmapheresis group (P = 0.03). As the baseline data were significantly different between the 2 groups, the propensity score match was further designed to avoid retrospective bias. After re-analysis, the plasmapheresis group still had a significant higher rate of remission and a lower ratio of treatment failure than that of the nonplasmapheresis group (P = 0.018). More importantly, the plasmapheresis group had significant less composite endpoints than that of the nonplasmapheresis group (P = 0.005).Our study suggested that additional plasmapheresis on conventional induction therapy may benefit patients with lupus nephritis-combined TMA, which warrants further explorations.

A Case of Retroperitoneal Castleman's Disease and an Update on the Latest Evidence

Castleman's disease is a benign lymphoproliferative condition with three distinct histological subtypes. Clinically it presents in either a unicentric or multicentric manner and can affect various anatomic regions, the mediastinum being the most frequent location. We herein present a rare case of unifocal retroperitoneal mass proved to be hyaline vascular Castleman's disease. We perform a review of the current literature pertaining to such lesions, focusing on the management of the various clinical and histological variants of the disease. Surgical excision is the treatment of choice for unifocal Castleman's disease.

Tocilizumab-induced remission of nephrotic syndrome accompanied by secondary amyloidosis and glomerulonephritis in a patient with rheumatoid arthritis

Rheumatoid arthritis (RA) is an autoimmune-mediated systemic disorder that primarily affects the musculoskeletal system. Patients with RA often present with kidney diseases, such as nephrotic syndrome. Causes of nephrotic syndrome include membranous nephropathy, IgA nephropathy and secondary amyloidosis. Recently, biological agents, including anti-tumor necrosis factor alpha and anti-interleukin 6 (IL-6) receptor antibodies, have been used for the treatment of RA. Anti-IL-6 receptor antibody therapy is believed to ameliorate RA-related kidney diseases, as IL-6 plays a central role in the pathogenesis of RA. We, herein, present the case of a patient with RA and related nephrotic syndrome whose proteinuria completely disappeared 1 month after tocilizumab treatment. A light microscopic examination of the pretreatment kidney biopsy specimen showed active glomerulonephritis with fibrocellular crescents and the deposition of amorphous substances stained weakly with hematoxylin-eosin and strongly with the Dylon method. Electron microscopy revealed the accumulation of microtubules ranging from 10 to 20 μm in width, primarily in the mesangial lesion. Amyloid A (AA) protein was positively stained in the mesangial area and vascular wall on immunohistochemistry. The final histologic diagnosis was RA-related glomerulonephritis and secondary AA amyloidosis. This case indicates that biological treatment targeting IL-6 is a promising therapeutic option for the treatment of kidney diseases associated with RA.

The first report of adolescent TAFRO syndrome, a unique clinicopathologic variant of multicentric Castleman's disease

BACKGROUND

TAFRO syndrome is a unique clinicopathologic variant of multicentric Castleman's disease that has recently been identified in Japan. It is characterized by a constellation of symptoms: Thrombocytopenia, Anasarca, reticulin Fibrosis of the bone marrow, Renal dysfunction and Organomegaly (TAFRO). Previous reports have shown that affected patients usually respond to immunosuppressive therapy, but the disease sometimes has a fatal course. TAFRO syndrome occurs in the middle-aged and elderly and there are no prior reports of the disease in adolescents. Here we report the first adolescent case, successfully treated with anti-IL-6 receptor antibody (tocilizumab, TCZ) and monitored with serial cytokine profiles.

CASE PRESENTATION

A 15-year-old Japanese boy was referred to us with fever of unknown origin. Whole body computed tomography demonstrated systemic lymphadenopathy, organomegaly and anasarca. Laboratory tests showed elevated C-reactive protein and hypoproteinemia. Bone marrow biopsy revealed a hyperplastic marrow with megakaryocytic hyperplasia and mild reticulin fibrosis. Despite methylprednisolone pulse therapy, the disease progressed markedly to respiratory distress, acute renal failure, anemia and thrombocytopenia. Serum and plasma levels of cytokines, including IL-6, vascular endothelial growth factor, neopterin and soluble tumor necrosis factor receptors I and II, were markedly elevated. Repeated weekly TCZ administration dramatically improved the patient's symptoms and laboratory tests showed decreasing cytokine levels.

CONCLUSION

To our knowledge, this is the first report of TAFRO syndrome in a young patient, suggesting that this disease can occur even in adolescence. The patient was successfully treated with TCZ. During our patient's clinical course, monitoring cytokine profiles was useful to assess the disease activity of TAFRO syndrome.

Sustained remission of severe Multicentric Castleman disease following multiagent chemotherapy and tocilizumab maintenance

Castleman disease is a rare lymphoproliferative disorder, which presents in a unicentric or multicentric fashion. Multicentric Castleman disease (MCD) is associated with significant systemic symptoms, in part related to the underlying role of interleukin-6 in disease pathogenesis. Treatment for MCD has not been well established and prognosis has historically been poor. We present a case of severe MCD in a pediatric patient who has shown sustained remission following multi-agent chemotherapy and targeted maintenance therapy with the interleukin-6 receptor inhibitor, tocilizumab. This represents the first case report of sustained remission of MCD in a pediatric patient following discontinuation of tocilizumab therapy.