Multicentric Castleman disease and the evolution of the concept

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.

Hematological Complications of Human Immunodeficiency Virus (HIV) Infection: An Update From an HIV-Endemic Setting

Medical professionals, particularly in regions with a high burden of human immunodeficiency virus (HIV), should be alert to the hematological complications of HIV, which may include cytopenias, malignancy, and coagulation disturbances. Patients may present with these conditions as the first manifestation of HIV infection. Hematological abnormalities are often multifactorial with opportunistic infections, drugs, malignancy, and HIV infection itself contributing to the clinical presentation, and the diagnosis should consider all these factors. Life-threatening hematological complications requiring urgent diagnosis and management include thrombotic thrombocytopenic purpura, superior mediastinal syndrome, spinal cord compression, and tumor lysis syndrome due to aggressive lymphoma. Antiretroviral therapy is the therapeutic backbone, including for patients with advanced HIV, in addition to specific therapy for the complication. This article reviews the impact of HIV on the hematological system and provides a clinical and diagnostic approach, including the role of a bone marrow biopsy, focusing on perspectives from sub-Saharan Africa.

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.

Retrospective cohort evaluation of non-HIV Castleman disease from a single academic center in Beijing, China

The purpose is to ascertain the clinical impact of Castleman disease (CD) by reassessment of the real-world data from Peking University First Hospital (PKUFH). The results will contribute to the standardization of diagnosis and treatment on CDs. Based on the last 15-year retrospective real-world data from Peking University First Hospital (PKUFH), we reclassified and re-evaluated the clinical and pathological information of patients with pathologically suspected diagnosis of CD. A total of 203 patients were included in our study, in which the diagnosis of CD was confirmed in 189 cases, including 118 patients with unicentric CD (UCD, n = 118, 62.4%) and 71 patients with multicentric CD (MCD, n = 71, 37.6%). A total of 44.1% (n = 52) of UCDs in our cohort were complicated with paraneoplastic pemphigus (PNP). The treatment of UCD is primarily surgical, with a 5-year overall survival (OS) of 88.1%. Patients with PNP had a poorer prognosis than those without PNP (82.9% (95% CI 123-178) vs 92.8% (95% CI 168-196), log-rank p = 0.041). The rate of concurrent systemic symptoms was 74.6% (n = 53), and renal involvement occurred in 49.3% (n = 35) MCD patients. The MCD treatments were mainly chemotherapy regimens, with a 5-year OS of 77.6% (95% CI, 143-213). Patients with UCD demonstrate a better overall prognosis than patients with MCD. But the prognosis of those complicated with PNP was poor. The differential diagnosis of MCD is extensive. MCD treatment in China is heterogeneous. The inaccessibility of anti-IL-6-targeted drugs in China may contribute to the poor prognosis for patients with MCD.A preprint has previously been published (Guo et al. 34).

A Rare Case of Orbital Castleman Disease with Overlapping IgG4-Related Disease

Multicentric Castleman disease (MCD) is a systemic lymphoproliferative disorder that can lead to mass lesions in various body parts, including the lungs, kidneys, and extranodal sites. Meanwhile, orbital Castleman disease is extremely rare. Immunoglobulin G4-related disease (IgG4-RD) is a recently recognized fibroinflammatory disorder and is characterized by the formation of tumor-like lesions with lymphoplasmacytic infiltrates, which are enriched in IgG4-positive plasma cells and may present with a characteristic storiform pattern of fibrosis to variable degrees. In this study, we report a case of a 67-year-old Taiwanese man with a 7-year history of bilateral eyelid swelling and proptosis. Orbital magnetic resonance imaging revealed soft tissue lesions in the bilateral intraconal region, demonstrating strong enhancement in the lacrimal glands, and extension into the bilateral infraorbital foramen, suggesting an orbital lymphoproliferative disease. The histopathological results of the intraorbital tumor excision were suggestive of a plasma-cell-predominant mixed-cell variant of MCD. However, the patient also showed definitive signs of IgG4-RD, including lacrimal gland enlargement and histopathological results of plasmacytosis, fibrosis, and germinal centers, with an increased ratio of IgG4 cells and elevated serum IgG4 levels. This case suggests a potential interacting pathway between these two disease entities that needs further studies.

Expert consensus on the integrated diagnosis of idiopathic multicentric Castleman disease

Idiopathic multicentric Castleman disease (iMCD) is rare. The differential diagnosis includes inflammatory, autoimmune and neoplastic disease. The identification of the histopathological features of Castleman disease in the lymph node is the main diagnostic criterion. Fifty-three experts from three medical societies (SEMI, SEHH and SEAP) have created a multi-disciplinary consensus document in order to standardise the diagnosis of Castleman disease. Using the Delphi method, specific recommendations for the initial clinical, laboratory and imaging studies have been made for an integrated diagnosis of iMCD as well as for the best way to obtain samples for histopathological confirmation, correct laboratory procedure and interpretation and reporting of results.

A novel approach for characterization of KSHV-associated multicentric Castleman disease from effusions

A biopsy of lymphoid tissue is currently required to diagnose Kaposi sarcoma-associated herpesvirus (KSHV)-associated multicentric Castleman disease (KSHV-MCD). Patients showing clinical manifestations of KSHV-MCD but no pathological changes of KSHV-MCD are diagnosed as KSHV inflammatory cytokine syndrome. However, a lymph node biopsy is not always feasible to make the distinction. A pathognomonic feature of lymph nodes in KSHV-MCD is the expansion of KSHV-infected, lambda-restricted but polyclonal plasmablasts. To investigate whether these cells also reside in extra-nodal sites, effusion from 11 patients with KSHV-MCD and 19 with KSHV inflammatory cytokine syndrome was analysed by multiparametric flow cytometry. A distinct, lambda-restricted plasmablastic population (LRP) with highly consistent immunophenotype was detected in effusions in 8/11 patients with KSHV-MCD. The same population was also observed in 7/19 patients with KSHV inflammatory cytokine syndrome. The detection of LRP stratified KSHV inflammatory cytokine syndrome into two clinically distinct subgroups; those with detectable LRP closely resembled KSHV-MCD, showing similar KSHV viral load, comparable severity of thrombocytopenia and hypoalbuminaemia, and similar incidences of hepatosplenomegaly. Collectively, the detection of LRP by flow cytometry can serve as a valuable tool in diagnosing KSHV-MCD. KSHV inflammatory cytokine syndrome with LRP in effusions may represent a liquid-form of KSHV-MCD.

Hyaline Vascular Type of Unicentric Castleman Disease in a Kidney with End-Stage Renal Disease: A Case Report of a Rare Entity at an Unusual Location and a Special Clinical Setting

Castleman disease (CD) is an unusual heterogeneous lymphoproliferative disorder that has been classified based on either clinical presentation and disease course or histologic features. Clinically, CD is divided into a unicentric CD (UCD) type and multicentric CD (MCD) type according to the extent of lymph node region involvement and the absence or presence of systemic symptoms. Histologically, it can be categorized into hyaline vascular (HV) type, plasma cell (PC) type and mixed type. The majority of HV-type CD involves a solitary lymph node, and excision surgery is often curative. On the contrary, MCD is a progressive and often fatal disease with lymphadenopathy in multiple nodes, and systemic therapy is needed. Herein we report a unique case of HV-type CD presenting as a single renal mass in a patient with end-stage renal disease (ESRD). Despite the rarity, CD should be included in the differential diagnosis of solitary renal mass lesions. An accurate diagnosis is important to avoid unnecessarily risky or extensive operations.

Idiopathic Multicentric Castleman Disease with Cutaneous Manifestation: Case Report

Castleman disease constitutes a rare class of lymphoproliferative disorders, with an estimated incidence of 21 to 25 per million patient years. The idiopathic subtype exhibits a significantly diverse clinical presentation, which can imitate many autoimmune, malignant, and infectious diseases. Cutaneous manifestations are uncommon and require in-depth investigation, especially when concurrent lymphadenopathy is present. A 79-year-old female, with a chronic, complicated erysipelas-like lesion, presented with bilaterally enlarged inguinal lymph nodes; after surgical excision, their histopathological examination revealed Castleman disease. Even though it is a benign condition, patients are often predisposed to developing certain types of malignancies, which can deteriorate their prognosis. An accurate and early diagnosis, along with effective treatment and prevention of recurrence, is of utmost importance in order to increase the patients’ overall survival and quality of life.

HHV-8 associated lymphoma

PURPOSE OF REVIEW

The discovery of Kaposi sarcoma herpesvirus (KSHV) / human herpesvirus 8 (HHV-8) led to recognition of primary effusion lymphoma (PEL) as a distinct lymphoproliferative disorder. Subsequently, two other types of lymphoma have been shown to be associated with HHV-8 : HHV-8 positive diffuse large B cell lymphoma not otherwise specified and germinotropic lymphoproliferative disorder.The pathogenesis of PEL is unique as in most cases the HHV-8+ tumoral cells are coinfected with the Epstein-Barr virus (EBV), suggesting an interplay between these two herpesviruses. This article reviews advances in the field of characterization of the lymphomatous cells, pathogenesis, and targeted therapies.

RECENT FINDINGS

The gene expression profile analysis of PEL cells and the experimental coinfection of peripheral B cells with HHV-8 and EBV allow dissection of the mechanisms of lymphomagenesis and of the relative contribution of both viruses. Systemic chemotherapy regimen remains poorly effective but new therapeutic perspectives are open with the use of monoclonal antibodies, immunomodulatory drugs, and immunotherapy.

SUMMARY

HHV-8 associated lymphoma is a model for studying virus-induced lymphoproliferation and its relation with host immune response and PEL is a unique model to study the relative contribution of two herpesviruses to lymphomagenesis in coinfected cells.

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.

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.