Clinical implications of idiopathic multicentric castleman disease among Japanese: a report of 28 cases

Overview of Research Status in Castleman Disease

Castleman disease (CD) is characterized by the proliferation of lymphoid tissue and encompasses a range of disorders that vary in clinical presentation, histopathological features, and therapeutic approaches. This article presents a comprehensive review of the current state of CD research, emphasizing the etiology, pathogenesis, clinical manifestations, diagnostic criteria, treatment options, and prognostic factors. CD is a relatively rare condition infrequently encountered in clinical practice. Certain subtypes of CD progress rapidly and pose a significant threat to patient health. Consequently, a timely and accurate diagnosis is crucial. This article aimed to equip clinicians and researchers with an updated and detailed understanding of CD, thereby enhancing the management of this complex condition.

The clinical picture of Castleman disease: a systematic review and meta-analysis

ABSTRACT

Castleman disease (CD) encompasses a spectrum of rare disorders, including unicentric CD (UCD), idiopathic multicentric CD (iMCD), and human herpesvirus 8-associated MCD (HHV8+ MCD). We performed a systematic review of publications reporting ≥5 cases of CD between 1995 and 2021, following preferred reporting items for systematic reviews and meta-analyses guidelines, to describe and compare subtypes. We extracted data on clinical symptoms and laboratory parameters as stated in international consensus diagnostic criteria for iMCD and estimated the frequency of each criterion using meta-analyses. We analyzed 32 studies describing 559 UCD, 1023 iMCD, and 416 HHV8+ MCD cases. Although many symptoms and laboratory abnormalities occurred at similar rates in patients with iMCD and HHV8+ MCD, patients with HHV8+ MCD had significantly higher rates of constitutional symptoms (46.6% vs 98.6%; P = .038) and splenomegaly (48.2% vs 89.2%; P = .031). Renal dysfunction was significantly more common in patients with iMCD than in patients with HHV8+ MCD before adjustment (36.9% vs 17.4%; P = .04; adjusted P = .1). Patients with UCD had lower rates of symptoms and laboratory abnormalities, although these were present in 20% of patients and were particularly pronounced in pediatric UCD. There are many similarities in the symptomatology of iMCD and HHV8+ MCD; many patients experience constitutional symptoms and organ dysfunction. Differences between these subtypes likely reflect differences in pathophysiology and/or comorbidity burdens.

Immunology and targeted therapy in Castleman disease

INTRODUCTION

Castleman disease (CD) is a benign lymphoproliferative disease causing severe systemic inflammation. Interleukin-6 (IL-6) is a major pathogenesis of multicentric CD (MCD), but only 30-60% of patients respond to IL-6 inhibitors. Novel agents for IL-6 inhibitor-refractory cases are needed. Clinical data and samples are being collected on a large scale and the clinical, pathological, and pathogenetic aspects are being elucidated.

AREAS COVERED

The pathological and clinical classification of CD is outlined. Focusing on idiopathic MCD (iMCD), this review identifies therapeutic targets and summarizes currently recommended drugs and promising therapeutic candidates.

EXPERT OPINION

The pathogenesis of MCD has been implicated in the activation of the Janus kinase (JAK)-transcriptional signaling activator (STAT) 3 pathway and the phosphatidylinositol 3-kinase (PI3K)/Akt/mechanical target of rapamycin (mTOR) signaling pathway. iMCD-TAFRO (thrombocytopenia, anasarca, fever/elevated CRP, reticulin myelofibrosis/renal dysfunction, organ enlargement) is resistant to IL-6 inhibitors, and cyclosporine and mTOR inhibitors are sometimes effective. JAK inhibitors and mTOR inhibitors may be therapeutic agents for iMCD. Recently, we have shown that peripheral helper T (Tph) cell abnormalities are at the core of iMCD pathogenesis. Therapies targeting chemokine (C-X-C motif) ligand 13 (CXCL13) produced by Tph cells and blocking the Tph-CXCL13-B cell pathway may satisfy unmet need in refractory cases.

TAFRO Syndrome: Guidance for Managing Patients Presenting Thrombocytopenia, Anasarca, Fever, Reticulin Fibrosis, Renal Insufficiency, and Organomegaly

TAFRO syndrome is an inflammatory disorder of unknown etiology characterized by thrombocytopenia, anasarca, fever, reticulin fibrosis, renal insufficiency, and organomegaly. Despite great advancements in research on the TAFRO syndrome in the last decade, its diagnosis and treatment are still challenging for most clinicians because of its rarity and severity. Since the initial proposal of the TAFRO syndrome as a distinct disease entity in 2010, two independent diagnostic criteria have been developed. Although these are different in the concept of whether TAFRO syndrome is a subtype of idiopathic multicentric Castleman disease or not, they are similar except for the magnitude of lymph node histopathology. Because there have been no specific biomarkers, numerous diseases must be ruled out before the diagnosis of TAFRO syndrome is made. The standard of care has not been fully established, but interleukin-6 blockade therapy with siltuximab or tocilizumab and anti-inflammatory therapy with high-dose corticosteroids are the most commonly applied for the treatment of TAFRO syndrome. The other immune suppressive agents or combination cytotoxic chemotherapies are considered for patients who do not respond to the initial treatment. Whereas glowing awareness of this disease improves the clinical outcomes of patients with TAFRO syndrome, further worldwide collaborations are warranted.

Stroma-Rich Hyaline Vascular Type of Castleman Disease: A Case Report and Literature Review

Castleman disease (CD) is a rare lymphoproliferative disorder characterized by abnormal lymph node enlargement. We present the first documented case of a stroma-rich variant of hyaline vascular Castleman disease in Saudi Arabia. A 24-year-old Saudi female known to have acetylcholine receptor antibody-positive myasthenia gravis (MG) presented with shortness of breath, oral thrush, and an acute myasthenia gravis exacerbation, necessitating intensive care unit (ICU) admission. During her hospitalization, she was found to have a large pelvic mass. The mass was surgically excised. The diagnosis of stroma-rich hyaline vascular Castleman disease was rendered after histopathological examination. The patient's symptoms improved after the surgery. This case underscores the importance of considering Castleman disease in complex clinical presentations, especially in the context of autoimmune and paraneoplastic diseases. Recognition and timely intervention are crucial for patient management. Additionally, the report adds to the global literature on Castleman disease, emphasizing the need for further research into its clinical manifestations and associations.

Idiopathic multicentric Castleman disease (iMCD)-idiopathic plasmacytic lymphadenopathy: A distinct subtype of iMCD-not otherwise specified with different clinical features and better survival

Idiopathic multicentric Castleman disease (iMCD) is subclassified into iMCD-thrombocytopenia, anasarca, reticulin fibrosis, renal dysfunction, organomegaly (TAFRO) and iMCD-not otherwise specified (NOS) according to the Castleman Disease Collaborative Network (CDCN) consensus criteria. With a deeper understanding of iMCD, a group of patients with iMCD-NOS characterised by polyclonal hypergammaglobulinaemia, plasmacytic/mixed-type lymph node histopathology and thrombocytosis has attracted attention. This group of patients has been previously described as having idiopathic plasmacytic lymphadenopathy (IPL). Whether these patients should be excluded from the current classification system lacks sufficient evidence. This retrospective analysis of 228 patients with iMCD-NOS identified 103 (45.2%) patients with iMCD-IPL. The clinical features and outcomes of patients with iMCD-IPL and iMCD-NOS without IPL were compared. Patients with iMCD-IPL showed a significantly higher inflammatory state but longer overall survival. No significant difference in overall survival was observed between severe and non-severe patients in the iMCD-IPL group according to the CDCN severity classification. Compared with lymphoma-like treatments, multiple myeloma-like and IL-6-blocking treatment approaches in the iMCD-IPL group resulted in significantly higher response rates and longer time to the next treatment. These findings highlight the particularities of iMCD-IPL and suggest that it should be considered a new subtype of iMCD-NOS.

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.

Diagnostic challenges of the idiopathic plasmacytic lymphadenopathy (IPL) subtype of idiopathic multicentric Castleman disease (iMCD): Factors to differentiate from IgG4-related disease

AIMS AND METHODS

Idiopathic multicentric Castleman disease (iMCD) is currently considered to be classified into three clinical subtypes, including idiopathic plasmacytic lymphadenopathy (IPL), thrombocytopaenia, anasarca, fever, reticulin fibrosis/renal dysfunction, organomegaly (TAFRO) and not otherwise specified (NOS). Among the three, iMCD-IPL closely mimics IgG4-related disease (IgG4-RD). In diagnosing IgG4-RD, it is sometimes challenging to distinguish iMCD-IPL patients that also meet the histological diagnostic criteria for IgG4-RD. In this study, we focused on the number of IgG4-positive cells in the lymph nodes and analysed the relationship with laboratory findings to distinguish iMCD-IPL from IgG4-RD. Thirty-nine patients with iMCD-IPL and 22 patients with IgG4-RD were included.

RESULTS

Among the cases considered to be iMCD-IPL, 33.3% (13/39) cases also met the histological diagnostic criteria for IgG4-RD and serum IgG4 levels were not different between the two groups. However, the serum IgG4/IgG ratio was significantly higher in IgG4-RD, with a cut-off value of 19.0%. Additionally, a significant positive correlation between serum IgG levels and the number of IgG4-positive cells was observed in iMCD-IPL (p=0.001). The serum IgG cut-off value for distinguishing iMCD-IPL meeting histological criteria for IgG4-RD from other iMCD-IPL was 5381 mg/dL.

CONCLUSIONS

iMCD-IPL cases with high serum IgG levels (>5000 mg/dL) were likely to meet the diagnostic criteria for IgG4-RD because of the numerous IgG4-positive cells observed. A combination of clinical presentations, laboratory values including the serum IgG4/IgG ratios and histological analysis is crucial for diagnosis of IgG4-RD and iMCD-IPL.

Concordance between transbronchial lung cryobiopsy and surgical lung biopsy in patients with idiopathic multicentric Castleman disease: A report of four cases

BACKGROUND

Idiopathic multicentric Castleman disease (iMCD) is a rare polyclonal lymphoproliferative disease often associated with pulmonary involvement. Recently, transbronchial lung cryobiopsy (TBLC) has been reported to be useful for the diagnosis of diffuse interstitial lung disease. However, there have been no reports of pathological assessment of TBLC for iMCD.

METHOD

To clarify the efficacy of TBLC in the diagnosis of iMCD, we retrospectively reviewed four iMCD patients who had undergone both TBLC and surgical lung biopsy (SLB).

RESULTS

The median age was 44 years; 2 males and 2 females. Two or three TBLC specimens were taken from each patient. All patients had no complications other than minimal bleeding. The size of the TBLC specimens was approximately 5-6 × 3-4 mm, and the alveolar region, and centrilobular and perilobular areas were adequately sampled. As with SLB, the extent of lung lesions and inflammatory cell infiltration could be sufficiently evaluated by TBLC. The presence of lymphoid follicles could also be assessed by TBLC; however, the germinal centers with lymphoid follicles were difficult to evaluate. The TBLC specimens could also be evaluated for immunostaining, especially IgG4 immunostaining, to rule out IgG4-related lung disease. Pulmonary pathological grading showed a high concordance rate between major pathological findings of TBLC and SLB. The pathologist's confidence level of TBLC for the diagnosis of iMCD was high in all cases.

CONCLUSIONS

TBLC exhibits a high concordance rate with SLB in the pathological evaluation of iMCD, which may be useful for the diagnosis of iMCD.

TAFRO syndrome: A disease that known is half cured

Thrombocytopenia, anasarca, fever, reticulin fibrosis/renal failure, and organomegaly (TAFRO) syndrome is rare in clinical practice. It is a systemic inflammatory disease caused by a cytokine storm. Its clinical manifestations include thrombocytopenia, systemic edema, fever, bone marrow fibrosis, renal insufficiency, and organ enlargement. The high mortality rate of TAFRO syndrome is due to the difficulty of acquiring biopsy samples for diagnosis and the rapid disease progression. This disease is poorly understood by clinicians. Early detection, accurate diagnosis, and timely treatment play key roles in prolonging the survival of the patients. This review summarizes the latest progress in the pathogenesis, diagnostic criteria, and treatment regimens of TAFRO syndrome, aiming to help clinicians better understand TAFRO syndrome and improve its diagnosis and treatment.

Unmet Clinical Needs in the Management of Idiopathic Multicentric Castleman Disease: A Consensus-based Position Paper From an ad hoc Expert Panel

Castleman disease describes a group of heterogeneous clinicopathological disorders now included in the tumor-like lesions with B-cell predominance of the World Health Organization classification. Managing idiopathic multicentric Castleman disease (iMCD) is challenging, because few systematic studies or comparative randomized clinical trials have been conducted. International, consensus evidence-based guidelines for iMCD were published in 2018, but gaps in the therapeutic options for difficult-to-treat patients, who do not respond to siltuximab and other conventional therapies, still exist. This article presents the results of group discussion among an ad hoc constituted Panel of Italian experts to identify and address unmet clinical needs (UCNs) in managing iMCD. Recommendations on the appropriateness of clinical decisions and proposals for new research concerning the identified UCNs were issued through formalized multiple-step procedures after a comprehensive analysis of the scientific literature. The following key UCNs were addressed: strengthening the diagnostic certainty in iMCD patients before planning first-line therapy; management of siltuximab therapy; choice and management of immune-modulating, or chemotherapy agents in patients resistant/intolerant to siltuximab therapy. While most of the conclusions reached by the Panel are consistent with the existing guidelines, some alternative therapeutic options were stressed, and the discussion contributed to bringing forth the issues that need further investigation. Hopefully, this comprehensive overview will improve the practice of iMCD and inform the design and implementation of new studies in the field.

Radiological and Pathological Features of Cyst Formation in Idiopathic Multicentric Castleman Disease

INTRODUCTION

Idiopathic multicentric Castleman disease (MCD) has been reported to form lung cysts at a relatively high rate. However, the radiological and pathological features of cystic formation in MCD are unclear.

METHODS

To clarify these questions, we retrospectively investigated the radiological and pathological findings of cysts in MCD patients. Eight consecutive patients who underwent surgical lung biopsies in our center from 2000 to 2019 were included.

RESULTS

The median age was 44.5 years, with three males and five females. On the initial computed tomography, cyst formation was found in seven patients (87.5%). All of the cysts were multiple, round, and thin walled, accompanying ground-glass attenuation (GGA) around cysts. In six patients (75%), cysts increased during their clinical courses, and the new cysts had emerged from GGA, although GGA was improved by treatment. In all four cases, whose pulmonary cysts could be pathologically evaluated, a marked plasma cell infiltration around the cyst wall, and loss of elastic fibers of the alveolar wall were observed.

CONCLUSIONS

Pulmonary cysts emerged in the area of GGA pathologically consistent with plasma cell infiltration. Cysts in MCD may be formed by the loss of elastic fibers due to marked plasma cell infiltration and may be considered irreversible changes.

TAFRO Syndrome: A Disease Requiring Immediate Medical Attention

TAFRO syndrome was first described in 2010, standing for thrombocytopenia, anasarca, fever, reticulin fibrosis and organomegaly. Because the lymph node histopathology of TAFRO syndrome mimics idiopathic multicentric Castleman disease (iMCD), some researchers consider TAFRO syndrome to be a subtype of iMCD. However, the clinical features of TAFRO syndrome considerably differ from those of iMCD without TAFRO. The clinical features of patients with TAFRO syndrome with or without iMCD-histopathology are similar, and these patients require an accurate diagnosis and urgent treatment. Although a histological diagnosis, including a differential diagnosis, is important, lymph node involvement in patients with TAFRO syndrome is usually modest or sometimes absent. Furthermore, a bleeding tendency due to thrombocytopenia and severe anasarca hampers performing a biopsy. Nonetheless, patients with various other disorders may manifest TAFRO syndrome-like symptoms, making the differential diagnosis in borderline cases difficult. Therefore, the establishment of precise and specific biomarkers is important.

Castleman disease and mimickers: Clinicopathological findings of atypical lymphoproliferative disorders associated with autoimmune disease

Atypical lymphoproliferative disorders (LPDs) related with autoimmune disease (AID) show marked clinicopathological diversity, which are defined as three distinct clinicopathological subtypes such as those resembling Castleman disease (CD), atypical paracortical hyperplasia with lymphoid follicles (APHLF), and atypical lymphoplasmacytic and immunoblastic proliferation (ALPIB). We studied excisional biopsy specimens from 31 patients with atypical LPDs associated with systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), and Sjögren syndrome (SjS). The lesions in these 31 cases were classified into 6 (19.4%) cases resembling CD, 14 (45.2%) cases of APHLF, and 11 (35.5%) cases of ALPIB. Five cases (83.3%) resembling CD were in the active stage with systemic symptoms and multicentric lymphadenopathy. Thirteen cases (92.9%) of APHLF showed systemic symptoms, multicentric lymphadenopathy and abnormal laboratory findings. Histologic findings for cases resembling CD were rare in patients with RA and SjS. In AID patients, histologic findings for cases resembling CD or APHLF findings correlated with disease activity and multicentric lymphadenopathy. Six cases (54.5%) of ALPIB were in the active phase with systemic symptoms and multicentric lymphadenopathy. ALPIB tended to be unrelated to AID activity, especially in the majority of patients with no abnormal laboratory findings. Atypical LPDs associated with AID is a group of diseases that may be overdiagnosed and overtreated. The diagnosis of atypical LPDs associated with AID requires an understanding of the histological findings as well as a comprehensive assessment of the presence of systemic symptoms, the distribution of lymphadenopathy, and abnormal laboratory findings.

Idiopathic Plasmacytic Lymphadenopathy Forms an Independent Subtype of Idiopathic Multicentric Castleman Disease

Idiopathic multicentric Castleman disease (iMCD) is a type of Castleman disease that is not related to KSHV/HHV8 infection. Currently, iMCD is classified into iMCD-TAFRO (thrombocytopenia, anasarca, fever, reticulin fibrosis, and organomegaly) and iMCD-NOS (not otherwise specified). The former has been established as a relatively homogeneous disease unit that has been recently re-defined, while the latter is considered to be a heterogeneous disease that could be further divided into several subtypes. In 1980, Mori et al. proposed the concept of idiopathic plasmacytic lymphadenopathy (IPL), a disease presenting with polyclonal hypergammaglobulinemia and a sheet-like proliferation of mature plasma cells in the lymph nodes. Some researchers consider IPL to be a part of iMCD-NOS, although it has not been clearly defined to date. This is the first paper to analyze iMCD-NOS clinicopathologically, to examine whether IPL forms a uniform disease unit in iMCD. Histologically, the IPL group showed prominent plasmacytosis and the hyperplasia of germinal centers, while the non-IPL group showed prominent vascularity. Clinically, the IPL group showed significant thrombocytosis and elevated serum IgG levels compared to the non-IPL group (p = 0.007, p < 0.001, respectively). Pleural effusion and ascites were less common in the IPL group (p < 0.001). The IPL group was more likely to have an indolent clinical course and a good response to the anti-IL-6 receptor antibody, while the non-IPL counterpart frequently required more aggressive medical interventions. Thus, the IPL group is a clinicopathologically uniform entity that forms an independent subtype of iMCD.

Idiopathic plasmacytic lymphadenopathy: A conceptual history along with a translation of the original Japanese article published in 1980

The current consensus on Castleman disease is that it is a group of several distinct lymphoproliferative disorders with different underlying pathogenesis and clinical outcomes. In 1980, Mori et al. proposed the concept of idiopathic plasmacytic lymphadenopathy with polyclonal hyperimmunoglobulinemia (IPL), a disease of unknown etiology, characterized by severe polyclonal hypergammaglobulinemia and generalized superficial lymphadenopathy. After Frizzera et al.’s landmark report in 1983, the term multicentric Castleman disease (MCD) gradually became established, and for a time, IPL was regarded as identical to MCD. However, with the subsequent recognition of human herpesvirus 8 (HHV8)-related MCD in the 1990s and the contributions by Kojima et al. in the 2000s, in which non-HHV8-related MCD (now called idiopathic MCD) was at least subclassified into IPL and others (non-IPL), it is now clear that the original distinctiveness of IPL is still maintained in MCD, which is a diverse collection of diseases.

Historical and pathological overview of Castleman disease

Castleman disease consists of several lymphoproliferative subtypes that share some histological features in the lymph nodes. On the other hand, numerous clinical findings and etiologies make the disease challenging to understand. The origin of the disease is the hyaline vascular-type unicentric Castleman disease (UCD), first reported by Benjamin Castleman et al. in 1954. Although UCD is characterized by localized lesions and lack of symptoms, multicentric Castleman disease (MCD) with multiple lesions and systemic symptoms was reported by Frizzera in 1983. MCD is further divided according to KSHV/HHV8 infection status. In KSHV/HHV8-related MCD, viral infection signals lead to excessive cytokine production, and cause clinical and pathologic abnormalities. Some cases of plasma cell-type KSHV/HHV8-negative MCD can be found in association with POEMS syndrome (polyneuropathy, organomegaly, endocrinopathy, M-proteins, and skin changes), which is a paraneoplastic syndrome. The others are idiopathic MCD, which are currently considered a heterogeneous group of diseases with overlapping pathological and clinical features. In this article, we summarize the historical evolution of Castleman disease to help understand the disease concept. We also review the latest ideas and definitions of the subtypes within the MCD spectrum and summarize the histopathological findings.

Castleman disease and TAFRO syndrome: To improve the diagnostic consciousness is the key

BACKGROUND

Castleman disease (CD) and TAFRO syndrome are very rare in clinical practice. Most clinicians, especially non-hematological clinicians, do not know enough about the two diseases, so it often leads to misdiagnosis or missed diagnosis.

AIM

To explore the clinical features and diagnosis of CD and TAFRO syndrome.

METHODS

We retrospectively collected the clinical and laboratory data of 39 patients who were diagnosed with CD from a single medical center.

RESULTS

Clinical classification identified 18 patients (46.15%) with unicentric Castleman disease (UCD) and 21 patients (53.85%) with multicentric Castleman disease (MCD), the latter is further divided into 13 patients (33.33%) with idiopathic multicentric Castleman disease-not otherwise specified (iMCD-NOS) and 8 patients (20.51%) with TAFRO syndrome. UCD and iMCD are significantly different in clinical manifestations, treatment, and prognosis. However, a few patients with MCD were diagnosed as UCD in their early stage. There was a correlation between two of Thrombocytopenia, anasarca and elevated creatinine, which were important components of TAFRO syndrome. In UCD group, the pathologies of lymph modes were mostly hyaline vascular type (13/18, 72.22%), however plasma cell type or mixed type could also appear. In iMCD-NOS group and TAFRO syndrome group, the pathologies of lymph mode shown polarity of plasma cell type and hyaline vascular type respectively. Compared with patients with TAFRO syndrome, patients with iMCD-NOS were diagnosed more difficultly.

CONCLUSION

The clinical and pathological types of CD are not completely separate, there is an intermediate situation or mixed characteristics between two ends of clinical and pathological types. The clinical manifestations of patients with CD are determined by their pathological type. TAFRO syndrome is a special subtype of iMCD with unique clinical manifestations.

Bone Marrow Findings of Idiopathic Multicentric Castleman Disease: A Histopathologic Analysis and Systematic Literature Review

Idiopathic multicentric Castleman disease (iMCD) is a polyclonal lymphoproliferative disorder characterized by constitutional symptoms, generalized lymphadenopathy, cytopenias, and multi-organ dysfunction due to excessive cytokines, notably Interleukin-6. iMCD is often sub-classified into iMCD-TAFRO, which is associated with thrombocytopenia (T), anasarca (A), fever/elevated C-reactive protein (F), renal dysfunction (R), and organomegaly (O), and iMCD-NOS, which is typically associated with thrombocytosis and hypergammaglobulinemia. The diagnosis of iMCD is challenging as consensus clinico-pathological diagnostic criteria were only recently established and include several non-specific lymph node histopathological features. Identification of further clinico-pathological features commonly found in iMCD could contribute to more accurate and timely diagnoses. We set out to characterize bone marrow (BM) histopathological features in iMCD, assess differences between iMCD-TAFRO and iMCD-NOS, and determine if these findings are specific to iMCD. Examination of BM specimens from 24 iMCD patients revealed a high proportion with hypercellularity, megakaryocytic atypia, reticulin fibrosis, and plasmacytosis across patients with both iMCD-NOS and iMCD-TAFRO with significantly more megakaryocytic hyperplasia (p=0.001) in the iMCD-TAFRO cases. These findings were also consistent with bone marrow findings from 185 published cases of iMCD-NOS and iMCD-TAFRO. However, these findings are relatively nonspecific as they can be seen in various other infectious, malignant, and autoimmune diseases. This article is protected by copyright. All rights reserved.

Castleman disease

Castleman disease (CD), a heterogeneous group of disorders that share morphological features, is divided into unicentric CD and multicentric CD (MCD) according to the clinical presentation and disease course. Unicentric CD involves a solitary enlarged lymph node and mild symptoms and excision surgery is often curative. MCD includes a form associated with Kaposi sarcoma herpesvirus (KSHV) (also known as human herpesvirus 8) and a KSHV-negative idiopathic form (iMCD). iMCD can present in association with severe syndromes such as TAFRO (thrombocytopenia, ascites, fever, reticulin fibrosis and organomegaly) or POEMS (polyneuropathy, organomegaly, endocrinopathy, monoclonal plasma cell disorder and skin changes). KSHV-MCD often occurs in the setting of HIV infection or another cause of immune deficiency. The interplay between KSHV and HIV elevates the risk for the development of KSHV-induced disorders, including KSHV-MCD, KSHV-lymphoproliferation, KSHV inflammatory cytokine syndrome, primary effusion lymphoma and Kaposi sarcoma. A CD diagnosis requires a multidimensional approach, including clinical presentation and imaging, pathological features, and molecular virology. B cell-directed monoclonal antibody therapy is the standard of care in KSHV-MCD, and anti-IL-6 therapy is the recommended first-line therapy and only treatment of iMCD approved by the US FDA and EMA.

Characteristics of thrombocytopenia, anasarca, fever, reticulin fibrosis and organomegaly syndrome: a retrospective study from a large Western cohort

Idiopathic multicentric Castleman disease (iMCD) is a non-clonal inflammatory lymphoproliferative disorder of unknown origin. Recently, TAFRO syndrome (thrombocytopenia, anasarca, fever, reticulin fibrosis and organomegaly) emerged as a singular variant of iMCD in Asia and was associated with a severe course and a poor outcome. The present study describes the first large Western cohort of TAFRO syndrome patients (n = 25) meeting the All Japan TAFRO Syndrome Research Group diagnostic criteria. Characteristics of TAFRO patients were compared to iMCD-not otherwise specified (iMCD-NOS) patients used as a control group (n = 43). Our results show that despite baseline characteristics in accordance with previously reported series, Western TAFRO syndrome patients do not appear to present with a worse outcome than iMCD-NOS patients. There were no significant differences between the two groups regarding treatment choice, response to rituximab (71% vs. 67%) or tocilizumab (69% vs. 91%) in TAFRO and iMCD-NOS, respectively. The two-year overall survival was above 95% in both groups. Limits of inclusion and exclusion criteria for TAFRO definition are also discussed. Our findings raise the question of the singularity of the TAFRO entity in Western countries. The data should promote further research using unsupervised models to identify markers of disease severity in Western cohorts of iMCD patients.

[A case report of TAFRO syndrome]

The study is to improve clinicians' understanding of TAFRO syndrome, to explore the diagnosis and treatment of TAFRO syndrome and to identify TAFRO syndrome in the early stage. The clinical manifestations, laboratory examination results, imaging manifestations, diagnosis and treatment of TAFRO syndrome were reported, and the literature of TAFRO syndrome was reviewed. The main clinical manifestations of the female were intermittent vaginal bleeding, fever, depressive edema of both legs, red blood cell and thrombocytopenia, and renal function deterioration. The results showed that leukocytes increased, anemia, thrombocytopenia and severe renal dysfunction were found; With fever, C-reactive protein and procalcitonin increased significantly, bone penetration suggested that granulocyte proliferation was active, and megakaryocytes were seen. But anti-infection treatment was ineffective; CT suggested that there was a high uptake of multiple fluorodeoxyglucose (FDG) in many parts of the body; The lymph node biopsy was considered to be in accordance with the transparent vascular type of Castleman disease; Renal biopsy was used to return thrombotic microvascular disease with subacute renal tubulointerstitial nephropathy. In terms of treatment, the clinical condition of the patients was improved after methylprednisolone (60 mg, once a day), the temperature was normal, and the effusion in the serous cavity was better than before. The blood transfusion and platelet support therapy were intermittently given. Hemoglobin and platelets were increased in sex, and the urine volume increased to 1 000 mL/day. However, the platelet dropped at a later time, after 1 month of treatment with topizumab, the clinical condition of the patients was further improved. At present, the blood pigment and platelets returned to normal and had been separated from dialysis. TAFRO syndrome is a special subtype of idiopathic multicentric Castleman disease, and it is a group of systemic inflammatory diseases with its own characteristics. Its clinical manifestations and diagnosis and treatment are unique compared with other idiopathic multicentric Castleman diseases. For the enlargement of lymph nodes of unknown reasons, it is suggested to improve the lymph node biopsy actively. Renal insufficiency is an important part of TAFRO syndrome. Renal biopsy is of great significance to study the pathogenesis of TAFRO syndrome and to judge the prognosis of patients. The clinical diagnosis of the disease requires comprehensive clinical manifestations and the results of various examinations. Early diagnosis and early treatment of the disease can often achieve good clinical effect.

Idiopathic Multicentric Hyaline Vascular-Type Castleman Disease

Castleman disease is a rare lymphoproliferative disorder presenting with localized or disseminated lymphadenopathy and systemic symptoms. It can be categorized clinically as unicentric or multicentric, histopathologically as hyaline vascular, plasma cell, or mixed variant, and etiologically, considering the subtypes based on causative viral agents and associated syndromes. The multicentric type can mimic other haematological malignancies, ranging from asymptomatic to multiple organ involvement. Although its pathophysiology is not well known, the current approved treatments are directed towards interleukin-6, CD-20, and viral agents. The authors present an 82-year-old leucodermic man presented with a 2-week history of constitutional symptoms. Examination revealed pallor, hepatosplenomegaly, and palpable left axillary lymphadenopathy. Investigation showed anaemia, thrombocytopenia, polyclonal hypergammaglobulinemia, hypoalbuminemia, and high acute phase reactants, with image study revealing multiple axillary, mediastinal, inguinal, and pelvic lymphadenopathies. The lymph node biopsy was consistent with hyaline vascular-type Castleman disease without human herpersvirus-8 markers. He started prednisolone with initial improvement evolved poorly on a short term. Castleman disease has a broad spectrum of clinical manifestations, associations, and complications that bring a diagnostic challenge, requiring a multidisciplinary approach. Clinicians should be familiar with its features because proper diagnosis and aggressive targeted treatment are the pillars of proper management of these patients.

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.

Multicentric Plasma-Cell Type Castleman Disease Masquerading As Hodgkin Lymphoma: A Case Report

Castleman disease (CD), or angiofollicular hyperplasia, or giant lymph node hyperplasia, is a heterogeneous benign lymphoproliferative disorder of unknown etiology. It has three distinct histologic subtypes (hyaline vascular, plasma cell, and mixed hyaline vascular plasma cell types) as well as unicentric Castleman disease (UCD) and multicentric Castleman disease (MCD) variants. In the unicentric form, the disease is confined to one anatomical lymph node and usually with no systemic symptoms. However, in the multicentric form (further subdivided into idiopathic MCD, human herpes virus-8-associated MCD, and POEMS-associated MCD), lymphadenopathy is more generalized with more aggressive systemic symptoms mimicking a malignant lymphoma. Therefore, this case report aims to underscore the importance of immunohistochemical evaluation as an indispensable ancillary technique to routine histopathological examination of a lymph node biopsy specimen, as a gold standard for definitive diagnosis of proliferative lymph node lesions.

[TAFRO syndrome and cutaneous necrotizing vasculitis]

INTRODUCTION

TAFRO syndrome is a systemic inflammatory syndrome in the spectrum of Castleman's disease, associating thrombocytopenia, anasarca, fever, renal failure and/or reticulin myelofibrosis and organomegaly. Its association with necrotizing cutaneous vasculitis has not yet been reported.

CASE REPORT

A 69-year-old woman presented with weight loss, fever, anasarca, organomegaly, lymphadenopathy, anuria and extensive necrotic livedo occurring after acute diarrhea. Biology showed anemia, thrombocytopenia, renal failure, hypergammaglobulinemia, a circulating B-lymphocyte clone, hypoparathyroidism and autoimmune hypothyroidism. The skin biopsy showed small vessel vasculitis with fibrinoid necrosis. Methylprednisolone infusions associated with tocilizumab were ineffective and the patient became anuric. Rituximab and plasma exchanges associated to corticosteroids allowed remission for 2 months. Combination of rituximab, cyclophosphamide and dexamethasone resulted in a prolonged remission.

CONCLUSION

We report here the first case of severe cutaneous necrotizing vasculitis in a patient suffering from TAFRO syndrome. The possible resistance to tocilizumab should be known.

Liver cirrhosis in a child associated with Castleman's disease: A case report

BACKGROUND

Castleman's disease (CD) is a lymphoproliferative disorder. TAFRO syndrome is classified as a variant of CD based on its key clinical manifestations of thrombocytopenia, anasarca (generalized edema and pleural effusion), fever (pyrexia), reticulin fibrosis in the bone marrow and the proliferation of megakaryocytes, and organomegaly (such as hepatosplenomegaly and multiple lymphadenopathies); TAFRO syndrome is mainly reported in Japanese patients. To our knowledge, this is the first pediatric case report detailing a CD-associated disorder progressing to cirrhosis.

CASE SUMMARY

A 10-year old male patient presented with fever and anemia. Six months before hospitalization, he had remarkable abdominal distention. Subsequently, he visited a clinic for a fever that lasted 5 d. The physical findings were marked hepatosplenomegaly and cervical lymphadenopathy. A blood test revealed leukocytosis, microcytic anemia, aspartate aminotransferase-dominant transaminase elevation, high levels of C-reactive protein, polyclonal hypergammaglobulinemia, and high levels of interleukin-6 and vascular endothelial growth factor. Abdominal contrast computed tomography and magnetic resonance imaging suggested cirrhosis, which was confirmed by liver histology. Histological findings in the enlarged hepatic lymph nodes revealed both hyperplasia and atrophy of lymphoid follicles with some vascular hyperplasia and moderate plasmacytosis between the lymphoid follicles, which is compatible with lymph node histology in TAFRO syndrome. Prednisolone was not effective in reducing the patient’s symptoms; therefore, the patient was prescribed tocilizumab. To date, the patient remains free of fever and continues to receive tocilizumab.

CONCLUSION

We described the clinicopathological features of TAFRO syndrome to highlight the clinical presentation of this rare disease in a pediatric case.

Clinical features and treatment of 7 Chinese TAFRO syndromes from 96 de novo Castleman diseases: a 10-year retrospective study

Background

Castleman disease (CD) is a rare polyclonal lymphoproliferative disorder with unknown etiology. TAFRO syndrome is now regarded as a specific subtype of CD, and is still a huge challenge for clinicians.

Methods

To clarify the clinical features and management of TAFRO syndrome in China, we retrospectively analyzed 96 patients with HIV-negative CD (52 with unicentric CD and 44 with multicentric CD), who were diagnosed and treated at our center between 2008 and 2017. Specially, we systematically reviewed the 7 TAFRO syndrome cases based on the 2015 criteria proposed by Masaki.

Results

Among the 7 cases, there were 3 men and 4 women, and the median age was 53 years. The main symptoms included thrombocytopenia (7/7), anasarca (7/7), fever (4/7), renal dysfunction (7/7), and organomegaly (6/7). One patient was treated with corticosteroid monotherapy, one received RD (Rituximab, dexamethasone), and 5 received CHOP/COP like chemotherapy as first-line treatment, 2 of the 5 combined with Rituximab. Four patients needed hemodialysis or CRRT because of progressive renal failure. The outcome for TAFRO syndrome was significantly worse compared to other types of CD. Although 3 patients improved after early treatment, 4 patients died due to disease progression, and only one patient achieved complete resolution of all the symptoms after changing to lenalidomide based regimen.

Conclusions

This study reveals that TAFRO syndrome is more severe and has more systemic symptoms than other iMCD, most cases need active treatment, and their prognoses are poor. Lenalidomide based regimen may be as a promising new therapy for TAFRO syndrome.

Epidemiological analysis of multicentric and unicentric Castleman disease and TAFRO syndrome in Japan

Castleman disease is a polyclonal lymphoproliferative disease which is clinically classified into unicentric (UCD) and multicentric (MCD). TAFRO syndrome is a relatively new concept that partly overlaps with MCD. Due to their rarity, their incidence remains unknown. This study investigated the incidence and prevalence of UCD, MCD, and TAFRO syndrome in Japan using a fixed-point observation method based on their incidence in Ishikawa prefecture. The annual incidences of MCD, UCD, and TAFRO syndrome in Japan were 309-731, 71-542, and 110-502, respectively, yielding annual incidence rates per million individuals of 2.4-5.8, 0.6-4.3, and 0.9-4.9, respectively, and nationwide prevalence of 4,180-14,900, 1,350-10,300, and 860-7,240, respectively. In conclusion, MCD, UCD and TAFRO syndrome may not be as rare as previously estimated in Japan.

Hepatic Campylobacter jejuni infection in patients with Castleman-Kojima disease (idiopathic multicentric Castleman disease with thrombocytopenia, anasarca, fever, reticulin fibrosis, and organomegaly (TAFRO) syndrome)

Castleman-Kojima disease, also known as idiopathic multicentric Castleman disease with TAFRO syndrome (iMCD-TAFRO), is a recently recognized systemic inflammatory disorder with a characteristic series of clinical symptoms, including thrombocytopenia (T), anasarca (A), fever (F), reticulin fibrosis (R), and organomegaly (O). Patients with iMCD-TAFRO often develop severe abdominal pain, elevated alkaline phosphatase levels, and systemic inflammation, but the etiological factors are unknown. To investigate the potential role of bacterial infection in the pathogenesis of iMCD-TAFRO, we performed polymerase chain reaction (PCR) for the bacterial 16S rRNA gene with DNA extracted from liver specimens of three patients with iMCD-TAFRO, four patients with amyotrophic lateral sclerosis, and seven patients with inflammatory conditions. Sequencing of the PCR product showed 99% DNA sequence identity with Campylobacter jejuni in all three patients with iMCD-TAFRO and in two patients with inflammatory conditions. Immunohistochemical and electron microscopy analyses could not identify C. jejuni in patients with iMCD-TAFRO. The findings indicated that C. jejuni infection is not the pathological cause of iMCD-TAFRO; however, this ubiquitous bacterium may play a role in uncontrolled systemic hypercytokinemia, possibly through the development of cross-reactive autoantibodies.

Clinicopathological Profile of Castleman's Disease in Indian Population: Experience From a Tertiary Care Center

Castleman's disease (CD), also known as angiofollicular lymph node hyperplasia, a rare, non-malignant chronic lymphoproliferative disease characterized by, uni or multicentric lymphadenopathy. There is limited information about the clinicopathological variations and associations of this entity. A total of 50 cases of CD were retrieved from the archives, between the years 2005-2017. The cases were divided into pediatric (0-18 years), young adult (age ≤ 40 years) and older adult groups (age > 40 years respectively). Detailed clinicopathological correlation was done. The age range was 6-74 years. There was a male predominance (M: F-1.6:1). The majority (72%; 36/50) of the patients were adults; 46% young adult and 28% older adult, while only 28% (14/50) were of pediatric. Majority (78%) showed features of unicentric Castleman disease (UCD) while rest 22% presented with multi centric Castleman disease (MCD). Systemic symptoms were more frequent in MCD as compared to UCD cases (p = 0.06). The majority of the cases (40/50; 80%) were of the hyaline vascular type. Two of the cases showed mixed histological feature. Out of 50 patients 29 patient's treatment details are available. Majority unicentric cases were cases surgically excised 14/17 (82.3%). Three patients 3/17 (17.6%) were treated with chemotherapy. In multicentric Castleman's disease group, six of the 12 cases with MCD were managed by chemotherapy. One patient died of progressive disease. Castleman disease has varied clinical presentation and is often associated with other diseases. A high degree of suspicion and careful histological examination is required in order not to miss this entity.

Is TAFRO syndrome a subtype of idiopathic multicentric Castleman disease?

Castleman disease (CD) is a rare lymphoproliferative disorder that can be unicentric or multicentric. Multicentric CD (MCD) is further subdivided into human herpesvirus type-8-associated, POEMS syndrome-associated, and idiopathic (iMCD). TAFRO syndrome is a newly identified disorder of unknown etiology characterized by thrombocytopenia, anasarca, fever, reticulin myelofibrosis, renal dysfunction, and organomegaly. The TAFRO syndrome is sometimes regarded as a subtype of iMCD (TAFRO-iMCD), whereas iMCD without TAFRO syndrome is considered "not otherwise specified" (iMCD-NOS). However, a proportion of patients with TAFRO syndrome have been diagnosed without lymph node biopsies (TAFRO syndrome without proven iMCD; TAFRO-w/op-iMCD). To clarify the clinical features of iMCD-NOS, TAFRO-iMCD, and TAFRO-w/op-iMCD, we retrospectively analyzed 220 patients extracted from the database of the Multicenter Collaborative Retrospective Study for Establishing the Concept of TAFRO Syndrome. The patients included 87 with iMCD-NOS, 63 with TAFRO-iMCD, and 19 with TAFRO-w/op-iMCD. Patients in all three groups exhibited anemia, hypoalbuminemia, and elevated serum C-reactive protein and interleukin-6 levels. No significant differences in clinical, laboratory, and prognostic features were noted between the TAFRO-iMCD, and TAFRO-w/op-iMCD groups. However, the iMCD-NOS group exhibited polyclonal hyper-γ-globulinemia. The five-year survival rates of patients in the iMCD-NOS and TAFRO-involved groups were 100% and 66.5%, respectively (dropping markedly during the first few months in the latter). The iMCD-NOS and the TAFRO-iMCD samples typically showed plasma cell and mixed-type histologies, respectively. Thus, iMCD can be classified into two distinct subtypes, iMCD-NOS and TAFRO-iMCD. As such, TAFRO-iMCD and TAFRO-w/op-iMCD may be considered the same entity, requiring prompt diagnosis and intensive care.

Osteosarcoma Manifesting Systemic Inflammation and Histological Features Mimicking Plasma Cell-type Castleman Disease

A 73-year-old man was referred to our hospital with a persistent fever, anemia, and a mass in the left pubic region. The findings of biopsy evaluations of the mass and a left inguinal lymph node were consistent with Castleman disease (CD) of plasma cell type. His serum interleukin 6 (IL-6) level was remarkably elevated, supporting the diagnosis of CD. However, imaging analyses revealed destruction of the pubic bone by the mass, which was atypical for CD. Therefore, another deeper biopsy was performed, which finally led to the diagnosis of IL-6-producing osteosarcoma. We conclude that clinicians should carefully exclude malignancies prior to making a CD diagnosis.

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.

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.

TAFRO syndrome: current perspectives

Multicentric Castleman’s disease (MCD), a distinct subtype of Castleman’s disease, is a rare, nonneoplastic, lymphoproliferative disorder. Patients with MCD present with systemic symptoms and multiple lymphadenopathy. Lymph node biopsy is necessary for the diagnosis of various histological MCD patterns including hyaline vascular, plasma cell, and mixed types. Human herpesvirus 8 (HHV8) infection was identified as an important etiology of MCD among immunocompromised patients such as those positive for human immunodeficiency virus. Although HHV8-negative MCD was reported in immunocompetent patients, the underlying etiology remains unknown. Several experts speculate that MCD in immunocompetent patients might be due to proinflammatory hypercytokinemia because of infection by a virus other than HHV8, inflammation, or neoplastic disease. In 2010, a distinct variant of HHV8-negative MCD reported in Japan was characterized by thrombocytopenia, anasarca, myelofibrosis, renal dysfunction, and organomegaly (TAFRO). Recent case reports and a systematic review suggest that TAFRO syndrome might have a unique pathogenesis among HHV8-negative MCD variants. This review introduces TAFRO syndrome as a subtype of HHV8-negative MCD and offers an overview of the current perspectives on this syndrome.

TAFRO Syndrome

TAFRO syndrome is a newly recognized variant of idiopathic multicentric Castleman disease (iMCD) that involves a constellation of syndromes: thrombocytopenia (T), anasarca (A), fever (F), reticulin fibrosis (R), and organomegaly (O). Thrombocytopenia and severe anasarca accompanied by relatively low serum immunoglobulin levels are characteristic clinical findings of TAFRO syndrome that are not present in iMCD-not otherwise specified (iMCD-NOS). Lymph node biopsy is recommended to exclude other diseases and to diagnose TAFRO syndrome, which reveals characteristic histopathological findings similar to hyaline vascular-type CD. TAFRO syndrome follows a more aggressive course, compared with iMCD-NOS, and there is no standard treatment.

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.

Tentative diagnostic criteria and disease severity classification for Castleman disease: A report of the research group on Castleman disease in Japan

OBJECTIVES

To determine the tentative diagnostic criteria and disease severity classification for Castleman disease (CD) and describe the clinical and pathologic features among human herpesvirus 8 (HHV-8) negative idiopathic multicentric CD (iMCD) in the Japanese population.

METHODS

We established the working groups for the research of CD in Japan and had meetings to discuss and define the tentative diagnostic criteria and disease severity classification for CD. We subsequently analyzed 142 patients classified into iMCD by using the nationwide Japanese patient registry.

RESULTS

We proposed the preliminary diagnostic criteria and disease severity classification for CD based on our discussion. In addition, we made a proposal for the disease activity score. We identified clinical and pathological features of patients with iMCD diagnosed by these diagnostic criteria. In the disease severity classification, 37, 33 and 30% patients were categorized into mild, moderate and severe diseases, respectively.

CONCLUSION

This is the first proposal for diagnosis and classification of CD by the Japanese group. Further studies are required to validate whether they can distinguish CD from other inflammatory diseases and to determine their sensitivity and specificity.

Comparison of clinical and pathological features of lung lesions of systemic IgG4-related disease and idiopathic multicentric Castleman's disease

AIMS

The lung lesion [immunoglobulin (Ig)G4-L] of IgG4-related disease (IgG4-RD) is a condition that occurs together with IgG4-RD and often mimics the lung lesion [idiopathic multicentric Castleman's disease (iMCD-L)] of idiopathic multicentric Castleman's disease (iMCD). Because no clinical and pathological studies had previously compared features of these diseases, we undertook this comparison with clinical and histological data.

METHODS AND RESULTS

Nine patients had IgG4-L (high levels of serum IgG4 and of IgG4⁺ cells in lung specimens; typical extrapulmonary manifestations). Fifteen patients had iMCD-L (polyclonal hyperimmunoglobulinaemia, elevated serum interleukin-6 levels and polylymphadenopathy with typical lymphadenopathic lesions). Mean values for age, serum haemoglobin levels and IgG4/IgG ratios were higher in the IgG4-L group and C-reactive protein levels were higher in the iMCD-L group. All IgG4-RD lung lesions showed myxomatous granulation-like fibrosis (active fibrosis), with infiltration of lymphoplasmacytes and scattered eosinophils within the perilymphatic stromal area, such as interlobular septa and pleura with obstructive vasculitis. All 15 lung lesions of iMCD, however, had marked accumulation of polyclonal lymphoplasmacytes in lesions with lymphoid follicles and dense fibrosis, mainly in the alveolar area adjacent to interlobular septa and pleura without obstructive vasculitis.

CONCLUSIONS

Although both lesions had lymphoplasmacytic infiltration, lung lesions of IgG4-RD were characterized by active fibrosis with eosinophilic infiltration within the perilymphatic stromal area with obstructive vasculitis, whereas lung lesions of iMCD had lymphoplasmacyte proliferating lesions mainly in the alveolar area adjacent to the perilymphatic stromal area. These clinicopathological features may help to differentiate the two diseases.

TAFRO syndrome with primary Sjogren's syndrome

A 25-year-old woman diagnosed 1 year earlier with Primary Sjogren's syndrome was admitted to a nearby hospital with fever of unknown origin. Examination revealed anasarca, systemic lymphadenopathy, hepatosplenomegaly and high C-reactive protein level. The patient's symptoms were initially suspected to be caused by severe bacterial infection with Sjogren's syndrome flare. She was given antibiotics and prednisolone (PSL) at 50 mg/day. However, the patient developed anemia and thrombocytopenia and was transferred to our hospital for further care. Histological examination of the right inguinal lymph node showed neutrophilic infiltration. Bone marrow aspiration revealed a normocellular marrow with increased megakaryocytes and mild reticulin fiber hyperplasia. After initiation of minocycline hydrochloride, the patient's symptoms improved. However, as PSL was tapered, her symptoms worsened. The patient's clinical symptoms and laboratory data improved again with initiation of intravenous steroid pulse therapy and cyclosporine. TAFRO syndrome is characterized by a constellation of symptoms: Thrombocytopenia, Anasarca, Fever, Reticulin fibrosis and Organomegaly. Although histological findings of the lymph node in this case differed from previous reports, the patient's other symptoms and clinical course were similar to TAFRO syndrome. TAFRO syndrome can occur with several diseases, including infection, rheumatic disease and malignancies. We report a case in which infection might have triggered TAFRO syndrome.