The role of immune suppression and HHV-8 in the increasing incidence of HIV-associated multicentric Castleman's disease

HIV-associated cancers and lymphoproliferative disorders caused by Kaposi sarcoma herpesvirus and Epstein-Barr virus

SUMMARYWithin weeks of the first report of acquired immunodeficiency syndrome (AIDS) in 1981, it was observed that these patients often had Kaposi sarcoma (KS), a hitherto rarely seen skin tumor in the USA. It soon became apparent that AIDS was also associated with an increased incidence of high-grade lymphomas caused by Epstein-Barr virus (EBV). The association of AIDS with KS remained a mystery for more than a decade until Kaposi sarcoma-associated herpesvirus (KSHV) was discovered and found to be the cause of KS. KSHV was subsequently found to cause several other diseases associated with AIDS and human immunodeficiency virus (HIV) infection. People living with HIV/AIDS continue to have an increased incidence of certain cancers, and many of these cancers are caused by EBV and/or KSHV. In this review, we discuss the epidemiology, virology, pathogenesis, clinical manifestations, and treatment of cancers caused by EBV and KSHV in persons living with HIV.

KSHV infection of B cells primes protective T cell responses in humanized mice

Kaposi sarcoma associated herpesvirus (KSHV) is associated with around 1% of all human tumors, including the B cell malignancy primary effusion lymphoma (PEL), in which co-infection with the Epstein Barr virus (EBV) can almost always be found in malignant cells. Here, we demonstrate that KSHV/EBV co-infection of mice with reconstituted human immune systems (humanized mice) leads to IgM responses against both latent and lytic KSHV antigens, and expansion of central and effector memory CD4+ and CD8+ T cells. Among these, KSHV/EBV dual-infection allows for the priming of CD8+ T cells that are specific for the lytic KSHV antigen K6 and able to kill KSHV/EBV infected B cells. This suggests that K6 may represent a vaccine antigen for the control of KSHV and its associated pathologies in high seroprevalence regions, such as Sub-Saharan Africa.

Lymphadenopathy in the rheumatology practice: a pragmatic approach

Lymphadenopathy is a common clinical finding and diagnostic challenge within general medicine and rheumatology practice. It may represent a primary manifestation of an underlying immune-mediated disease or indicate an infectious or neoplastic complication requiring differing management. Evaluating lymphadenopathy is of particular relevance in rheumatology, given that lymph node enlargement is a common finding within the clinical spectrum of several well-known rheumatologic disorders including RA, SLE and SS. In addition, lymphadenopathy represents a hallmark manifestation of rare immunological diseases such as Castleman disease and IgG4-related disease that must be considered in the differential diagnosis because effective targeted treatments can now impact the prognosis of these conditions. In this review we present an overview of the clinical significance of lymphadenopathy in common and rare rheumatologic diseases and propose a practical approach to lymphadenopathy in the rheumatology practice. Differential diagnosis of Castleman disease and therapeutic options for this condition of increasing rheumatologic interest will be discussed in detail.

The Impact of Co-Infections for Human Gammaherpesvirus Infection and Associated Pathologies

The two oncogenic human gammaherpesviruses Epstein-Barr virus (EBV) and Kaposi's sarcoma-associated herpesvirus (KSHV) cause significant disease burden, particularly in immunosuppressed individuals. Both viruses display latent and lytic phases of their life cycle with different outcomes for their associated pathologies. The high prevalence of infectious diseases in Sub-Saharan Africa (SSA), particularly HIV/AIDS, tuberculosis, malaria, and more recently, COVID-19, as well as their associated inflammatory responses, could potentially impact either virus' infectious course. However, acute or lytically active EBV and/or KSHV infections often present with symptoms mimicking these predominant diseases leading to misdiagnosis or underdiagnosis of oncogenic herpesvirus-associated pathologies. EBV and/or KSHV infections are generally acquired early in life and remain latent until lytic reactivation is triggered by various stimuli. This review summarizes known associations between infectious agents prevalent in SSA and underlying EBV and/or KSHV infection. While presenting an overview of both viruses' biphasic life cycles, this review aims to highlight the importance of co-infections in the correct identification of risk factors for and diagnoses of EBV- and/or KSHV-associated pathologies, particularly in SSA, where both oncogenic herpesviruses as well as other infectious agents are highly pervasive and can lead to substantial morbidity and mortality.

Clinical management of Kaposi sarcoma herpesvirus-associated diseases: an update on disease manifestations and treatment strategies

INTRODUCTION

Kaposi sarcoma herpes virus (KSHV) is associated with several diseases including Kaposi sarcoma, a form of multicentric Castleman's disease, primary effusion lymphoma, and an inflammatory cytokine syndrome. These KSHV-associated diseases (KAD) can present with heterogenous signs and symptoms that are often associated with cytokine dysregulation that may result in multiorgan dysfunction. The inability to promptly diagnose and treat these conditions can result in long-term complications and mortality.

AREAS COVERED

Existing epidemiological subtypes of existing KSHV-associated diseases, specifically Kaposi sarcoma as well as the incidence of several KSHV-associated disorders are described. We review the KSHV latent and lytic phases as they correlate with KSHV-associated diseases. Given the complicated presentations, we discuss the clinical manifestations, current diagnostic criteria, existing treatment algorithms for individual KAD, and when they occur concurrently. With emerging evidence on the virus and host interactions, we evaluate novel approaches for the treatment of KAD. An extensive literature search was conducted to support these findings.

EXPERT OPINION

KSHV leads to complex and concurrent disease processes that are often underdiagnosed both in the United States and worldwide. New therapies that exist for many of these conditions focus on chemotherapy-sparing options that seek to target the underlying viral pathogenesis or immunotherapy strategies.

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.

Case report: Multicentric Castleman disease as a manifestation of immune reconstitution inflammatory syndrome in Malawi

Introduction

Multicentric Castleman disease (MCD) is a lymphoproliferative disorder characterized by systemic inflammation, lymphadenopathy, and cytopenias. MCD caused by Kaposi sarcoma herpesvirus (MCD-KSHV) frequently arises in the context of HIV. It can be associated with immune reconstitution inflammatory syndrome (IRIS), but MCD-IRIS is rarely reported in sub-Saharan Africa (SSA) where HIV and KSHV infection are common.

Case description

A 36-year-old woman in Malawi with HIV on antiretroviral therapy (ART) for nine years presented with fatigue, weight loss, and lymphadenopathy. Lymph node biopsy was consistent with HIV lymphadenitis without evident KSHV-MCD and HIV RNA was 4,244 copies/mL. She switched to second-line ART and returned four months later with worsening lymphadenopathy, fever, night sweats, weight loss, and anemia. A repeat lymph node biopsy demonstrated unequivocal KSHV-MCD features not present on the original biopsy. Her repeat HIV viral load was undetectable and she received chemotherapy with subsequent remission on continued ART for 24 months.

Discussion

This is among the first reported cases of MCD-IRIS from SSA, which has implications for a region where HIV and KSHV are highly prevalent. MCD-IRIS may contribute to early mortality after ART initiation in SSA, and increased awareness alongside improved diagnostic and treatment capacity are needed.

Maladies de Castleman : épidémiologie, classification et critères diagnostiques

Castleman disease is a group of rare disorders characterized by lymph node enlargement, specific microscopic changes to the lymph nodes, and a broad range of symptoms and laboratory findings. The two main subtypes are unicentric Castleman disease (UCD) and multicentric Castleman disease (MCD). The multicentric subtype can be further classified into two categories: HHV-8 positive multicentric Castleman disease and idiopathic multicentric Castleman disease (iMCD). In the United States (US), the annual incidence of Castleman disease (CD) has been estimated to range from 6500 to 7700 in a 2014 study. Approximately 75 percent were estimated to be unicentric CD and the remaining 25 percent were estimated to be split between HHV-8-associated MCD or HHV-8-negative/idiopathic MCD. Diagnostic criteria for iMCD have been established by an international working group of pediatric and adult pathology and clinical experts. The proposed consensus criteria require characteristic histopathologic findings on lymph node biopsy, enlargement of multiple lymph node regions, the presence of multiple clinical and laboratory abnormalities, and the exclusion of infectious, malignant, and autoimmune disorders that can mimic iMCD. © 2022 Published by Elsevier Masson SAS on behalf of Société nationale française de médecine interne (SNFMI).

The Role of Radiotherapy in Treating Kaposi’s Sarcoma in HIV Infected Patients

Kaposi’s sarcoma (KS) is a radiosensitive cancer regardless of its form (classical, endemic, AIDS-related, and immunosuppressant therapy-related). Radiotherapy (RT) is an integral part of the therapeutic management of KS. RT may be used as the main treatment, in the case of solitary lesions, or as palliative therapy in the disseminated forms. The dose of RT to be delivered is 20–30 Gy by low-energy photons or by electrons. The complete response rate after RT is high, around 80–90%. This treatment is well tolerated. However, patients should be informed of the possible risk of the development of late skin sequelae and the possibility of recurrence. With the advent of highly active antiretroviral therapy (HAART), the indications for RT treatment in HIV-positive patients have decreased.

KSHV/HHV8-mediated hematologic diseases

Kaposi sarcoma (KS) herpesvirus (KSHV), also known as human herpesvirus 8, is the causal agent of KS but is also pathogenetically related to several lymphoproliferative disorders, including primary effusion lymphoma (PEL)/extracavitary (EC) PEL, KSHV-associated multicentric Castleman disease (MCD), KSHV+ diffuse large B-cell lymphoma, and germinotropic lymphoproliferative disorder. These different KSHV-associated diseases may co-occur and may have overlapping features. KSHV, similar to Epstein-Barr virus (EBV), is a lymphotropic gammaherpesvirus that is preferentially present in abnormal lymphoid proliferations occurring in immunecompromised individuals. Notably, both KSHV and EBV can infect and transform the same B cell, which is frequently seen in KSHV+ EBV+ PEL/EC-PEL. The mechanisms by which KSHV leads to lymphoproliferative disorders is thought to be related to the expression of a few transforming viral genes that can affect cellular proliferation and survival. There are critical differences between KSHV-MCD and PEL/EC-PEL, the 2 most common KSHV-associated lymphoid proliferations, including viral associations, patterns of viral gene expression, and cellular differentiation stage reflected by the phenotype and genotype of the infected abnormal B cells. Advances in treatment have improved outcomes, but mortality rates remain high. Our deepening understanding of KSHV biology, clinical features of KSHV-associated diseases, and newer clinical interventions should lead to improved and increasingly targeted therapeutic interventions.

HHV-8-Associated Multicentric Castleman Disease, a Diagnostic Challenge in a Patient With Acquired Immunodeficiency Syndrome and Fever

Patients with acquired immunodeficiency syndrome (AIDS) are at an increased susceptibility to pathogens and associated malignancies which can present with a unique constellation of symptoms. In this article, we describe a case of Castleman disease in a patient with AIDS, nonadherent with antiretroviral therapy (ART), who presented with fevers, constant abdominal pain, nausea, and vomiting. After an extensive work up, a lymph node biopsy confirmed a diagnosis of human herpesvirus-8 (HHV-8)-associated multicentric Castleman disease. Patients presenting with AIDS and fever have broad differential diagnoses; therefore, reaching a diagnosis as rare as Castleman disease can be challenging. HHV-8 has a propensity to CD20 positive B cells, which allows rituximab to be an effect treatment.

Dimethyl Sulfoxide Enhances Kaposi’s Sarcoma-Associated Herpesvirus Production During Lytic Replication

Kaposi’s sarcoma-associated herpesvirus (KSHV) is an etiologic agent of Kaposi’s sarcoma, primary effusion lymphoma, and multicentric Castleman disease. In studies of KSHV, efficient virus production and isolation are essential. Reactivation of KSHV can be initiated by treating latently infected cells with chemicals, such as 12-O-tetradecanoyl-phorbol-13-acetate and sodium butyrate. These chemicals have been used as tools to induce lytic replication and viral production in KSHV-producing cell lines. Dimethyl sulfoxide (DMSO) is an organosulfur compound that is frequently used as an aprotic solvent similar to water. In experiments exploring signaling pathways in KSHV-infected cells, DMSO treatment alone as a vehicle affected the lytic gene expression of KSHV. However, to the best of our knowledge, the effects of DMSO on KSHV-producing cells have not yet been reported. Therefore, in this study, we investigated whether DMSO could be used as a reagent to enhance viral production during lytic replication in KSHV-producing cells and assessed the underlying mechanisms. The effects of DMSO on KSHV production were analyzed in iSLK BAC16 cells, which have been widely used for recombinant KSHV production. We found that the production of KSHV virions was significantly increased by treatment with DMSO during the induction of lytic replication. Mechanistically, lytic genes of KSHV were enhanced by DMSO treatment, which was correlated with virion production. Additionally, DMSO induced the phosphorylation of JNK during lytic replication, and inhibition of JNK abolished the effects of DMSO on lytic replication and virion production. Our findings showed that additional treatment with DMSO during the induction of lytic replication significantly improved the yield of KSHV production.

Human herpesvirus 8-associated multicentric Castleman disease in a patient with advanced HIV infection: A case report

RATIONAL

Multicentric Castleman disease (MCD) is a nonclonal lymphoproliferative disorder that is rarely reported from Southeast Asian countries. Here, we report a case of human herpesvirus 8 (HHV-8)-associated MCD in a patient with advanced human immunodeficiency virus (HIV) infection who presented with prolonged intermittent fever, urticarial rash, hepatosplenomegaly, and generalized lymphadenopathy.

PATIENT CONCERNS

A 34-year-old man with advanced HIV infection who was in good compliance with his antiretroviral treatment regimen presented with intermittent fever, weight loss, marked hepatosplenomegaly, and generalized lymphadenopathy. Recurrent symptoms of high-grade fever, abdominal discomfort, pancytopenia, and high C-reactive protein level occurred for 16 months.

DIAGNOSES

Histopathological findings of left inguinal lymph node revealed diffuse effacement of lymph node architecture with coexpression of HHV-8 latency-associated nuclear antigen 1 from immunohistochemical staining. The HHV-8 viral load was 335,391 copies/mL.

INTERVENTIONS

The patient was treated initially with one dose of intravenous rituximab (375 mg/m2) followed by subcutaneous rituximab (1400 mg) weekly for 5 weeks.

OUTCOMES

The patient's recurrent systemic symptoms subsided dramatically, and he has now been in remission for almost two years.

LESSONS

HHV8-associated MCD remains a diagnostic challenge in advanced HIV disease and should be suspected in those with recurrent flares of systemic inflammatory symptoms. Lymph node histopathology is essential for diagnosis and for excluding clonal malignancy. HHV-8 viral load is also useful for diagnosis and for monitoring disease activity.

[HHV-8 Related immunological and hematological diseases]

HHV-8 is an oncogenic Gammaherpesvirinae discovered in 1994 during the HIV pandemic. It is the causative agent of Kaposi's sarcoma, and is also associated with the occurrence of several aggressive B lymphoproliferative disorders. Most of them occur in an immunosuppression setting, usually due to HIV infection. Multicentric HHV8-associated Castleman's disease and KSHV Inflammatory Cytokine Syndrome (KICS) are primarily reactive entities with prominent systemic features. They illustrate the cytokinic storm induced by HHV-8 in its cell host. On the other hand, HHV-8 can drive proliferation and lymphomagenesis of its plasmablastic cell host, and is associated with a risk to develop aggressive lymphomas with plasmacytic differenciation. Primary effusion lymphoma usually localizes in body cavities and may affect other extra-nodal sites ; its prognostic is poor. Diffuse large B-cell lymphoma HHV-8, NOS affect more commonly nodes and blood and evolve from infected cell of HHV-8 associated Castleman disease. On the contrary, germinotropic lymphoproliferative disorders presents mainly as localized adenopathy with indolent course, and show polyclonality. Histology plays a key role in distinguishing these different entities and need expert reviewing, especially since they may be associated with each other. Besides lymphoproliferative disorders, HHV8 is associated with various hematological manifestations. The aim of this review is to provide an update on the presentation, diagnosis, and management of immunologic and hematologic complications associated with HHV-8.

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.

Concurrent HIV viral blips during two episodes of multicentric Castleman disease in an adult on antiretroviral therapy: Implication for HIV persistence

Human herpesvirus-8 (HHV8)-associated multicentric Castleman disease (HHV8-MCD) is a rare nonmalignant lymphoproliferative disorder most commonly observed in PLWH. Herein, we describe an HIV-infected adult male from Cameroon with relapsing HHV8-MCD (HIV+MCD). The patient developed constitutional symptoms, diffuse lymphadenopathy, thrombocytopenia and autoimmune hemolytic anemia. Excisional lymph node biopsy findings were consistent with HHV8-MCD. He was successfully treated with corticosteroids and rituximab. One year later, he developed relapsing disease and was successfully treated again with rituximab. Interestingly, HIV viral load blips correlate with MCD flares, suggesting that low-level viremia is linked with T-cell clonal expansion and/or inflammation, rather than a lack of effective antiretroviral therapy. Rituximab either alone or in combination with chemotherapy for aggressive disease is the standard of care, with approximately 95% of treated patients achieving complete remission. Despite highly effective therapy, HIV+MCD often presents with a relapsing and remitting disease course and carries an increased risk for the development of HHV8-associated lymphoma.

Hematological cancers in individuals infected by HIV

HIV infection increases cancer risk and is linked to cancers associated to infectious agents classified as carcinogenic to humans by the International Agency for Research on Cancer. Lymphomas represent one of the most frequent malignancies among individuals infected by HIV. Diffuse large B-cell lymphoma remains a leading cancer after the introduction of combined antiretroviral therapy (cART). The incidence of other lymphomas including Burkitt lymphoma, primary effusion lymphomas, and plasmablastic lymphoma of the oral cavity remain stable, while the incidence of Hodgkin lymphoma and Kaposi sarcoma-associated herpesvirus (KSHV)-associated Multicentric Castleman Disease has increased. The heterogeneity of lymphomas in individuals infected by HIV likely depends on the complexity of involved pathogenetic mechanisms, i.e. HIV-induced immunosuppression, genetic abnormalities, cytokine dysregulation, co-infection with the gamma-herpesviruses, Epstein Barr virus and KSHV, and the dysregulation of the immune responses controlling these viruses. In the modern cART era, standard treatments for HIV-associated lymphoma including stem cell transplantation in relapsed/refractory disease, mirrors that of the general population. The combination of cART and anti neoplastic treatments has resulted in remarkable prolongation of long-term survival. However, oncolytic and immunotherapic strategies, and therapies targeting specific viral oncogenes will need to be developed primarily.

IgG4-related disease and idiopathic multicentric Castleman's disease: confusable immune-mediated disorders

IgG4-related disease (IgG4-RD) and idiopathic multicentric Castleman's disease (iMCD) are both rare systemic immune-mediated disorders. However, pathogenesis differs markedly between the two diseases, and differing therapeutic strategies are adopted: IgG4-RD is treated using a moderate dose of glucocorticoids or rituximab, while iMCD therapy involves an interleukin (IL)-6 targeted approach. Nonetheless, some clinical features of IgG4-RD and iMCD overlap, so differential diagnosis is sometimes difficult, even though the classification and diagnostic criteria of the diseases require careful exclusion of the other. The key findings in IgG4-RD are high IgG4/IgG ratio, allergic features, and germinal centre expansion involving T follicular helper cells, while iMCD involves polyclonal antibody production (high IgA and IgM levels), sheet-like mature plasma cell proliferation, and inflammatory features driven by IL-6. The distribution of organ involvement also provides important clues in both diseases. Particular attention should be given to differential diagnosis using combined clinical and/or pathological findings, because single features cannot distinguish IgG4-RD from iMCD. In the present review, we discuss the similarities and differences between IgG4-RD and iMCD, as well as how to distinguish the two diseases.

A Case of Successful Allogeneic Hematopoietic Stem Cell Transplantation for HHV8-Positive Castleman's Disease with a Review of the Literature

Objective:

To investigate the long-term clinical efficacy of allogeneic hematopoietic stem cell transplantation (allo-HSCT) for patients with human herpes virus 8 (HHV8)-positive multicentric Castleman’s disease (MCD).

Methods:

A 17-year-old female patient was admitted to Henan Provincial People’s Hospital with the complaint of febrile for half a month, headache, and enlarged superficial lymph nodes on October 5, 2010. HHV8-positive mixed cellular Castleman’s disease was found by pathological diagnosis of lymph nodes biopsy. After the administration of CHOP and Hyper-CVAD-B, the patient was still febrile, we administrated the followed COAP, two courses of VAD(Vincristine, Adriamycin, Dexamethasone), the patient received CR. Six months after CR, the patient relapsed, we administrated VAD and two courses of bortezomide+dexamethasone chemotherapy, and then the patient received PR. After that, the patient underwent allo-HSCT from his human leukocyte antigen (HLA)-matched unrelated donor after conditioning with Bu/Cy+Etoposide+Smoustin.graft-vs-host disease (GVHD) prophylaxis, which consisted of ATG (7.5 mg/kg, qd, ivdrip) from d-5 to d-2, cyclosporine (3 mg/kg/d, qd, ivdrip, for 24 h) started from day-1, MMF(0.5 g, tid, po.) started from day+1 to +28, and MTX (15 mg per time, ivdrip, d+1,+4,+7,+11). She received 3.5×10⁶/L CD34⁺cells and 8.1×10⁸/LMNC.

Results:

Granulocyte engraftment occurred on day+12, platelet engrafted on day+14. Bone marrow biopsy showed normalization of trilineage hematopoiesis on day+33, chimerism: 97.6%. The transplantation was successful and followed up for 7 years with CR.

Conclusion:

Allo-HSCT might cure patients with refractory/relapsed HHV8+ MCD.

[Human immunodeficiency virus and lymphoma]

Lymphomas remain a leading cause of morbidity and mortality for HIV-positive patients. The most common lymphomas include diffuse large B-cell lymphoma, Burkitt lymphoma, primary effusion lymphoma, plasmablastic lymphoma and Hodgkin lymphoma. Appropriate approach is determined by lymphoma stage, performans status, comorbidities, histological subtype, status of the HIV disease and immunosuppression. Treatment outcomes have improved due to chemotherapy modalities and effective antiretroviral therapy. This review summarizes epidemiology, pathogenesis, pathology, and current treatment landscape in HIV associated lymphoma.

From HIV to Coronavirus Disease 2019 (COVID-19): Hematologic Complications in Viral Pandemics

CONTEXT.—

From the onset of the human immunodeficiency virus (HIV) pandemic in the 1980s to the recent coronavirus disease 2019 (COVID-19) pandemic, multiple viral pandemics have occurred and all have been associated with hematologic complications of varying severity.

OBJECTIVE.—

To review the hematologic complications associated with the HIV and other viral pandemics, the current theories regarding their causation, and the incidence and clinical impact of these complications on infected patients.

DATA SOURCES.—

Peer-reviewed medical literature and the author's personal experience.

CONCLUSIONS.—

The HIV and other viral pandemics have been associated with a variety of hematologic complications that often cause significant morbidity and mortality in affected patients. HIV infection is associated with multiple hematologic disorders, many of which have a lower incidence in the era of highly active antiretroviral therapy but still represent a major clinical problem for HIV-infected patients. Our understanding of the pathogenesis of HIV-related hematologic complications, including HIV-associated lymphoproliferative disorders, has evolved in recent years. Other viral pandemics, including H1N1 influenza, severe acute respiratory syndrome (SARS) coronavirus, Middle East respiratory syndrome (MERS) coronavirus, and COVID-19, have also been associated with hematologic complications of varying severity. Our emerging understanding of the pathogenesis of the hematologic complications of HIV, COVID-19, and other viral pandemics may help in prevention, correct diagnosis, and treatment of these complications in current and future pandemics.

Multicentric Castleman's disease in HIV patients: a single-center cohort diagnosed from 2008 to 2018

Purpose

Castleman’s disease (CD) is a well-established entity but there is a lack of available data regarding the management and therapy of HIV- and HHV-8-positive multicentric CD (MCD). We provide our own single-center experience with HIV-associated MCD.

Methods

We performed a retrospective, descriptive study on a cohort of patients with MCD, diagnosed and admitted to the infectious diseases or intensive care unit in the University Hospital Düsseldorf between 2008 and 2018. Included patients had a previous or new HIV diagnosis and clinical signs resembling MCD with evidence of HHV-8 replication or histological diagnosis for MCD.

Results

Nine male patients were included in the study. All patients were treated with Rituximab after diagnosis of MCD, with six of them acquiring resolution of symptoms. Three patients received tocilizumab additionally. Other treatment options included: splenectomy (2/9), valganciclovir (2/9), vincristine and siltuximab (1/9), ruxolitinib and Cytosorb^® (2/9). The relapse rate was 44% (4/9) and the survival rate 87.5% after 1 year (8/9) and 71.4% after 3 years (5/7).

Conclusion

The most effective first-line therapy and retreatment option remains rituximab. The effectiveness of other treatment options like splenectomy or different immunotherapeutic approaches requires confirmation in larger-scale studies.

Emerging role of 18F-FDG PET/CT in Castleman disease: a review

Castleman disease (CD) describes a group of rare hematologic conditions involving lymphadenopathy with characteristic histopathology and a spectrum of clinical abnormalities. CD is divided into localized or unicentric CD (UCD) and multicentric CD (MCD) by imaging. MCD is further divided based on etiological driver into human herpesvirus-8-associated MCD, POEMS-associated MCD, and idiopathic MCD. There is notable heterogeneity across MCD, but increased level of pro-inflammatory cytokines, particularly interleukin-6, is an established disease driver in a portion of patients. FDG-PET/CT can help determine UCD versus MCD, evaluate for neoplastic conditions that can mimic MCD clinico-pathologically, and monitor therapy responses. CD requires more robust characterization, earlier diagnosis, and an accurate tool for both monitoring and treatment response evaluation; FDG-PET/CT is particularly suited for this. Moving forward, future prospective studies should further characterize the use of FDG-PET/CT in CD and specifically explore the utility of global disease assessment and dual time point imaging.

Trial registration ClinicalTrials.gov, NCT02817997, Registered 29 June 2016, https://clinicaltrials.gov/ct2/show/NCT02817997

Evidence for altered host genetic factors in KSHV infection and KSHV-related disease development

Kaposi's sarcoma-associated herpesvirus (KSHV) is the etiological agent of Kaposi's sarcoma (KS), the most common AIDS-related malignancy. It also causes other rare, but certainly underreported, KSHV-associated pathologies, namely primary effusion lymphoma, multicentric Castleman disease and KSHV inflammatory cytokine syndrome. Epidemiology and pathogenicity studies point to the potential for host genetic predisposition to KSHV infection and/or the subsequent development of KSHV-associated pathologies partly explaining the peculiar geographic and population-specific incidence of KSHV and associated pathologies and discrepancies in KSHV exposure and infection and KSHV infection and disease development. This review consolidates the current knowledge of host genetic factors involved in the KSHV-driven pathogenesis. Studies reviewed here indicate a plausible connection between KSHV susceptibility and host genetic factors that affect either viral access to host cells via entry mechanisms or host innate immunity to viral infection. Subsequent to infection, KSHV-associated pathogenesis, reviewed here primarily in the context of KS, is likely influenced by an orchestrated concert of innate immune system interactions, downstream inflammatory pathways and oncogenic mechanisms. The association studies reviewed here point to interesting candidate genes that may prove important in achieving a more nuanced understanding of the pathogenesis and therapeutic targeting of KSHV and associated diseases. Recent studies on host genetic factors suggest numerous candidate genes strongly associated with KSHV infection or subsequent disease development, particularly innate immune system mediators. Taken together, these contribute toward our understanding of the geographic prevalence and population susceptibility to KSHV and KSHV-associated diseases.

Overview of Castleman disease

Castleman disease (CD) describes a group of at least 4 disorders that share a spectrum of characteristic histopathological features but have a wide range of etiologies, presentations, treatments, and outcomes. CD includes unicentric CD (UCD) and multicentric CD (MCD), the latter of which is divided into idiopathic MCD (iMCD), human herpes virus-8 (HHV8)-associated MCD (HHV8-MCD), and polyneuropathy, organomegaly, endocrinopathy, monoclonal plasma cell disorder, skin changes (POEMS)-associated MCD (POEMS-MCD). iMCD can be further subclassified into iMCD-thrombocytopenia, ascites, reticulin fibrosis, renal dysfunction, organomegaly (iMCD-TAFRO) or iMCD-not otherwise specified (iMCD-NOS). Advances in diagnosis, classification, pathogenesis, and therapy are substantial since the original description of UCD by Benjamin Castleman in 1954. The advent of effective retroviral therapy and use of rituximab in HHV8-MCD have improved outcomes in HHV8-MCD. Anti-interleukin-6-directed therapies are highly effective in many iMCD patients, but additional therapies are required for refractory cases. Much of the recent progress has been coordinated by the Castleman Disease Collaborative Network (CDCN), and further progress will be made by continued engagement of physicians, scientists, and patients. Progress can also be facilitated by encouraging patients to self-enroll in the CDCN's ACCELERATE natural history registry (#NCT02817997; www.CDCN.org/ACCELERATE).

Epidemiology of haematological malignancies in people living with HIV

People living with HIV or AIDS are at increased risk of Hodgkin and non-Hodgkin lymphoma compared with HIV-negative individuals. Data on the risk of multiple myeloma or leukaemia are inconsistent and of low quality but the risk does not seem to be increased. Specific haematological malignancies occur in different contexts of age, CD4 cell count, HIV control, viral co-infections, or chronic inflammation, and the expansion of combination antiretroviral therapy has led to varied demographic and epidemiological shifts among people with HIV. Increased use of combination antiretroviral therapy has substantially reduced the risks of diffuse large B-cell lymphoma, Burkitt lymphoma, and primary CNS lymphoma, and to a lesser extent, Hodgkin lymphoma. There is no effect of combination antiretroviral therapy use on multiple myeloma or leukaemia. Although many cases of HIV are in low-income and middle-income countries, high-quality epidemiological data for haematological malignancies from these regions are scarce. Closing this gap is an essential first step in decreasing mortality from HIV-associated haematological malignancies worldwide. Finally, although multicentric Castleman disease is not a neoplastic condition, it is an emerging precursor to neoplastic high-grade B-cell lymphoproliferation among people with HIV, especially for individuals on long-term combination antiretroviral therapy with well controlled HIV.

Treatment management of haematological malignancies in people living with HIV

Although the incidence of HIV-associated lymphomas decreased after the introduction of effective combination antiretroviral therapy, they became the most common AIDS-related cancer in high-income countries. Moreover, as people living with HIV live longer, a wide range of non-AIDS-related cancer has emerged, including other haematological malignancies. Nonetheless, combination antiretroviral therapy has offered people with HIV the opportunity to receive the same therapies as those provided to the general population, and intensive curative therapies have become the standard. However, several population-based studies highlight a major health-care disparity between people with HIV and those without, with people who are HIV positive often excluded from using innovative therapies and participating in prospective trials. In addition, patients from low-income countries frequently receive inappropriate treatment. The hope is that with increased awareness of effective curative options these disparities will decrease, and people with HIV will be given the same therapeutic opportunities and enrolled in clinical trials alongside patients who are HIV negative.

Updates on the diagnosis and management of multicentric Castleman disease

Multicentric Castleman disease (MCD) is an uncommon systemic lymphoproliferative disease. The diagnosis of this disease is typically challenging and requires collaboration between clinicians and pathologists. Moreover, it is important to exclude other diseases (such as malignancies, autoimmune diseases, and infectious diseases) that have similar clinical manifestations and pathological findings. Patients with untreated severe MCD have high mortality due to devastating cytokine storms. Thus, early diagnosis and prompt treatment is a key imperative. The diagnosis of MCD is based on the clinical signs of systemic inflammation, serological tests, and typical pathological features. In this review article, we provide an overview of MCD with a focus on the emerging evidence pertaining to its diagnosis and treatment.

Dual infection and recombination of Kaposi sarcoma herpesvirus revealed by whole-genome sequence analysis of effusion samples

Kaposi sarcoma herpesvirus (KSHV) is the etiological agent of three malignancies, Kaposi sarcoma (KS), primary effusion lymphoma (PEL) and KSHV-associated multicentric Castelman disease. KSHV infected patients may also have an interleukin six-related KSHV-associated inflammatory cytokine syndrome. KSHV-associated diseases occur in only a minority of chronically KSHV-infected individuals and often in the setting of immunosuppression. Mechanisms by which KSHV genomic variations and systemic co-infections may affect the pathogenic pathways potentially leading to these diseases have not been well characterized in vivo. To date, the majority of comparative genetic analyses of KSHV have been focused on a few regions scattered across the viral genome. We used next-generation sequencing techniques to investigate the taxonomic groupings of viruses from malignant effusion samples from fourteen participants with advanced KSHV-related malignancies, including twelve with PEL and two with KS and elevated KSHV viral load in effusions. The genomic diversity and evolutionary characteristics of nine isolated, near full-length KSHV genomes revealed extensive evidence of mosaic patterns across all these genomes. Further, our comprehensive NGS analysis allowed the identification of two distinct KSHV genome sequences in one individual, consistent with a dual infection. Overall, our results provide significant evidence for the contribution of KSHV phylogenomics to the origin of KSHV subtypes. This report points to a wider scope of studies to establish genome-wide patterns of sequence diversity and define the possible pathogenic role of sequence variations in KSHV-infected individuals.

Kaposi's Sarcoma-Associated Herpesvirus and Host Interaction by the Complement System

Kaposi’s sarcoma-associated herpesvirus (KSHV) modulates the immune response to allow the virus to establish persistent infection in the host and facilitate the development of KSHV-associated cancer. The complement system has a central role in the defense against pathogens. Hence, KSHV has adopted an evasion strategy for complement attack using the viral protein encoded by KSHV open reading frame 4. However, despite this defense mechanism, the complement system appears to become activated in KSHV-infected cells as well as in the region surrounding Kaposi’s sarcoma tumors. Given that the complement system can affect cell fate as well as the inflammatory microenvironment, complement activation is likely associated with KSHV pathogenesis. A better understanding of the interplay between KSHV and the complement system may, therefore, translate into the development of novel therapeutic interventions for KSHV-associated tumors. In this review, the mechanisms and functions of complement activation in KSHV-infected cells are discussed.

HIV-Related Lymphoproliferative Diseases in the Era of Combination Antiretroviral Therapy

HIV-positive patients have a 60- to 200-fold increased incidence of Non-Hodgkin Lymphomas (NHL) because of their impaired cellular immunity. Some NHL are considered Acquired Immunodeficiency Syndrome (AIDS) defining conditions. Diffuse large B-cell Lymphoma (DLBC) and Burkitt Lymphoma (BL) are the most commonly observed, whereas Primary Effusion Lymphoma (PEL), Central Nervous System Lymphomas (PCNSL), Plasmablastic Lymphoma (PBL) and classic Hodgkin Lymphoma (HL) are far less frequent. Multicentric Castleman disease (MCD) is an aggressive lymphoproliferative disorder highly prevalent in HIV-positive patients and strongly associated with HHV-8 virus infection. In the pre-Combination Antiretroviral Therapy (CART) era, patients with HIV-associated lymphoma had poor outcomes with median survival of 5 to 6 months. By improving the immunological status, CART extended the therapeutic options for HIV positive patients with lymphomas, allowing them to tolerate standard chemotherapies regimen with similar outcomes to those of the general population. The combination of CART and chemotherapy/ immuno-chemotherapy treatment has resulted in a remarkable prolongation of survival among HIVinfected patients with lymphomas. In this short communication, we briefly review the problems linked with the treatment of lymphoproliferative diseases in HIV patients. Combination Antiretroviral Therapy (CART) not only reduces HIV replication and restores the immunological status improving immune function of the HIV-related lymphomas patients but allows patients to deal with standard doses of chemotherapies. The association of CART and chemotherapy allowed to obtain better results in terms of overall survival and complete responses. In the setting of HIVassociated lymphomas, many issues remain open and their treatment is complicated by the patient's immunocompromised status and the need to treat HIV concurrently.

Immunodeficiencies that predispose to pathologies by human oncogenic γ-herpesviruses

Human γ-herpesviruses include the closely related tumor viruses Epstein Barr virus (EBV) and Kaposi sarcoma-associated herpesvirus (KSHV). EBV is the most growth-transforming pathogen known and is linked to at least seven human malignancies. KSHV is also associated with three human cancers. Most EBV- and KSHV-infected individuals fortunately remain disease-free despite persistent infection and this is likely due to the robustness of the immune control that they mount against these tumor viruses. However, upon immune suppression EBV- and KSHV-associated malignancies emerge at increased frequencies. Moreover, primary immunodeficiencies with individual mutations that predispose to EBV or KSHV disease allow us to gain insights into a catalog of molecules that are required for the immune control of these tumor viruses. Curiously, there is little overlap between the mutation targets that predispose individuals to EBV versus KSHV disease, even so both viruses can infect the same host cell, human B cells. These differences will be discussed in this review. A better understanding of the crucial components in the near-perfect life-long immune control of EBV and KSHV should allow us to target malignancies that are associated with these viruses, but also induce similar immune responses against other tumors.

AIDS-Associated Malignancies

Malignancies were one of the earliest recognized manifestations that led to the description of the acquired immune deficiency syndrome (AIDS). The majority of cancers in AIDS patients are associated with coinfection with oncogenic viruses, such as Epstein-Barr virus, human herpesvirus 8, and human papillomavirus, with resulting malignancies occurring secondary to diminished immune surveillance against viruses and virus-infected tumor cells. Over 50% of AIDS lymphomas are associated with Epstein-Barr virus (EBV) and/or HHV8 infection. HHV8-associated diseases include Kaposi sarcoma (KS), primary effusion lymphoma (PEL), and multicentric Castleman disease (MCD). EBV is associated with several malignancies, including Hodgkin lymphoma (HL) and non-Hodgkin lymphoma (NHL). Coinfection with HIV and HPV is associated with an increased risk of various squamous cell carcinomas of epithelial tissues. HAART has significantly impacted the incidence, management, and prognosis of AIDS-related malignancies. In addition to changing the natural history of HIV infection in regard to incidence and survival, HAART has dramatically decreased the incidence of certain virally mediated HIV-associated malignancies such as KS and primary CNS lymphoma. The beneficial effects of HAART on these tumors are attributed to drug-mediated HIV suppression and immune reconstitution. However, HAART has had a less favorable impact on EBV- and HPV-related malignancies. This chapter presents an overview of HIV-associated malignancies mediated by HHV-8, EBV, and HPV, and reviews the effect of HAART on the epidemiology, presentation, treatment, and outcomes of these cancers.

Castleman's disease in the HIV-endemic setting

Introduction

Castleman’s disease (CD), first described by Benjamin Castleman in 1954, is a giant or angiofollicular lymph node hyperplasia, described as a rare monotypic polyclonal B-cell lymphoproliferative disorder with an incompletely understood pathogenesis and variable clinical behavior. This study aimed to determine the incidence of CD diagnosis over an 11-year period. Additionally, the study aimed to describe the demographic, laboratory, and pathological features of CD.

Methods

This is a retrospective study where the demographic and laboratory data were retrieved from the Tygerberg Academic Hospital (TAH) patient electronic records and Tygerberg Lymphoma Study Group (TLSG) and statistical analysis performed on the patients diagnosed with CD.

Results

Fifty-four patients were diagnosed with CD during this period. The median age at presentation was 39 years (range: 9–58). HIV serology was available in 53 patients, of which 51 were HIV-positive and two were HIV-negative. The history of initiation of antiretroviral therapy at diagnosis was available in 43 patients (38 on treatment, four were not on treatment, and one defaulted treatment). The median CD4 count was 232.50 cells/μL (range: 2–883). The HIV viral load was performed in 43 patients at diagnosis, which was <49 HIV-1 RNA copies/μL in more than half of the patients (58%). Diagnosis was made on lymph node biopsies in 53 patients, with one case diagnosed on a spleen biopsy. Kaposi sarcoma was found on the same tissue biopsy in 13 cases. A bone marrow biopsy was performed in 31 patients. The predominant features noted were a disorganized hypercellular marrow with plasmocytosis.

Conclusion

CD is a rare polyclonal B-cell lymphoproliferative disorder. However, we demonstrated a significant increase in the incidence of HIV-associated multicentric CD over the last decade in our area in South Africa.

Biologic Agents in the Treatment of Multicentric Castleman Disease

Multicentric Castleman disease (MCD) causes an extensive range of systematic symptoms and can be life-threatening if not treated promptly and appropriately. The pathophysiology of the disease remains unclear; however, interleukin 6 (IL-6) pathway and human herpesvirus 8 infection appear to play an important role. As a result, the treatment of MCD remains complex and often insufficient, although a plethora of therapeutic approaches have been used. Between these, biological agents in the form of monoclonal antibodies against specific pathogenic processes of the disease have improved survival rates significantly. In the present study, we review the clinical results of rituximab, which targets B lymphocytes, siltuximab and tocilizumab, which target the IL-6 pathway, bortezomib, which is a selective proteasome inhibitor, and anakinra, which is an interleukin 1 receptor antagonist. The introduction of these biological agents in the treatment of MCD appears to be promising in the first studies performed. However, more clinical trials are required to assess the efficacy and safety of each agent and to form therapeutic strategies that will be widely accepted.

Malignant lymphoma in the HIV-positive patient

The introduction of combination antiretroviral therapy (cART) drastically improved performance status, immune function, and life expectancy of HIV-infected individuals. In addition, incidence of opportunistic infections and of AIDS-defining malignancies declined. Nevertheless, aggressive non-Hodgkin's lymphoma still remains the leading cause of AIDS-related deaths. The availability of cART, however, significantly improved the therapeutic options for HIV-positive patients with lymphomas. Diffuse large B-cell lymphoma, Burkitt's lymphoma, or Hodgkin lymphoma has increasingly become curable diseases. In light of these favorable developments in the treatment of HIV and HIV-associated lymphomas, reduction in treatment-associated toxicities and further improvement of outcome of patients with advanced immune suppression are major requirements for future clinical trials. This review summarizes the current treatment landscape and gives an overview on future needs in HIV-positive patients with lymphoma.

Human herpesvirus-encoded kinase induces B cell lymphomas in vivo

Kaposi's sarcoma-associated herpesvirus (KSHV) is a gammaherpesvirus that is the etiological agent of the endothelial cell cancer Kaposi's sarcoma (KS) and 2 B cell lymphoproliferative disorders, primary effusion lymphoma (PEL) and multicentric Castleman's disease (MCD). KSHV ORF36, also known as viral protein kinase (vPK), is a viral serine/threonine kinase. We previously reported that KSHV vPK enhances cell proliferation and mimics cellular S6 kinase to phosphorylate ribosomal protein S6, a protein involved in protein synthesis. We created a mouse model to analyze the function of vPK in vivo. We believe this is the first mouse tumor model of a viral kinase encoded by a pathogenic human virus. We observed increased B cell activation in the vPK transgenic mice compared with normal mice. We also found that, over time, vPK transgenic mice developed a B cell hyperproliferative disorder and/or a high-grade B cell non-Hodgkin lymphoma at a greatly increased incidence compared with littermate controls. This mouse model shows that a viral protein kinase is capable of promoting B cell activation and proliferation as well as augmenting lymphomagenesis in vivo and may therefore contribute to the development of viral cancers.

Clinical, laboratory and imaging findings in Castleman's disease - The subtype decides

Castleman's disease (CD) is a rare lymphoproliferative disorder with its distinct unicentric (uCD) and multicentric (mCD) entities. The present work aimed at characterizing CD in more detail. From the 775 articles found by a PubMed search, 1133 cases were extracted. Two own cases were included. UCD was identified in 719 (42% males) and mCD in 416 (63% males) cases. Age in uCD was 34±17 and in mCD 48±18years. The hyaline-vascular type predominated in uCD and the plasma cell type in mCD. Clinical symptoms were more common in mCD. The head and neck region was most frequently affected in uCD and the axillary region in mCD. Prevalence of human immunodeficiency virus (HIV) and human herpesvirus-8 (HHV-8) positivity was higher in mCD. In CT scans, high contrast enhancement and calcifications were more frequent in uCD (all p<0.0001). The two forms of CD not only differ markedly in their clinical, laboratory and imaging findings, but also in treatment response and prognosis.

Omega-3 decreases IL-6 levels in HIV and human herpesvirus-8 coinfected patients in Uganda

OBJECTIVE

Kaposi sarcoma is a HIV-associated malignancy caused by human herpesvirus-8 (HHV-8) that occurs at highest incidence in sub-Saharan Africa. Kaposi sarcoma patients often present with inflammatory symptoms associated with higher mortality.

DESIGN

We conducted a double-blind, randomized, placebo-controlled study in Uganda to test whether omega-3 supplementation could reduce inflammation in HIV and HHV-8 coinfected adults. Patients with acute illness, AIDS, or advanced Kaposi sarcoma were ineligible, as were pregnant women. Participant IDs were pre-randomized, blocked by Kaposi sarcoma status, to either the omega-3 or placebo arm.

METHODS

Omega-3 participants received a 3-g pill dose daily for 12 weeks (1.8-g eicosapentaenoic acid, 1.2-mg docosapentaenoic acid); placebo participants received 44.8 mg of high oleic safflower oil that appeared indistinguishable from the active supplement. Intervention effects were evaluated as the baseline-adjusted mean difference after 12 weeks between omega-3 and placebo participants in concentrations of fatty acids, inflammatory cytokines, and immune cells.

RESULTS

The final study population included 56 Kaposi sarcoma patients and 11 Kaposi sarcoma-negative, HIV and HHV-8-positive participants randomized to receive either omega-3 (N = 33) or placebo (N = 34). Inflammatory cytokine IL-6 concentrations decreased in omega-3 participants (-0.78 pg/ml) but increased in placebo participants (+3.2 pg/ml; P = 0.04). We observed a trend toward decreased IL-6 after omega-3 supplementation specific to Kaposi sarcoma patients (P = 0.08). CD8 T-cell counts tended to increase in the omega-3 arm Kaposi sarcoma patients (+60 cells/μl), in contrast to decreases (-47 cells/μl) among placebo (P = 0.11).

CONCLUSION

Omega-3 supplementation decreased IL-6 concentrations among HIV and HHV-8 coinfected Ugandans, which may have clinical benefit for Kaposi sarcoma patients.

GESIDA/PETHEMA recommendations on the diagnosis and treatment of lymphomas in patients infected by the human immunodeficiency virus

The incidence of non-Hodgkin's lymphoma and Hodgkin's lymphoma is higher in patients with HIV infection than in the general population. Following the introduction of combination antiretroviral therapy (cART), the prognostic significance of HIV-related variables has decreased, and lymphoma-related factors have become more pronounced. Currently, treatments for lymphomas in HIV-infected patients do not differ from those used in the general population. However, differentiating characteristics of seropositive patients, such as the need for cART and specific prophylaxis and treatment of certain opportunistic infections, should be considered. This document updates recommendations on the diagnosis and treatment of lymphomas in HIV infected patients published by GESIDA/PETHEMA in 2008.

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.

Treatment of Kaposi Sarcoma Herpesvirus-Associated Multicentric Castleman Disease

Kaposi sarcoma herpesvirus (KSHV)-associated multicentric Castleman disease (MCD) is a rare, polyclonal lymphoproliferative disorder characterized by flares of inflammatory symptoms, edema, cytopenias, lymphadenopathy, and splenomegaly. Diagnosis requires a lymph node biopsy. Pathogenesis is related to dysregulated inflammatory cytokines, including human and viral interleukin-6. Rituximab alone or in combination with chemotherapy, such as liposomal doxorubicin, has led to an overall survival of over 90% at 5 years. Experimental approaches to treatment include virus activated cytotoxic therapy with high-dose zidovudine and valganciclovir and targeting human interleukin-6 activity. Despite successful treatment of KSHV-MCD, patients remain at high risk for developing non-Hodgkin lymphomas.

Epidemiology of Castleman Disease

Castleman disease is a rare entity, including unicentric Castleman disease (UCD), human herpesvirus-8 plus Castleman disease (HHV-8+MCD), and idiopathic multicentric Castleman disease (iMCD). UCD is the most common at 16 per million person years and occurs at every age. HHV-8+MCD incidence varies widely, mostly affecting human immunodeficiency virus-positive men. iMCD is likely a more heterogeneous disease with an estimated incidence of 5 per million person years. Improved definitions should improve understanding of the epidemiology of Castleman disease and its subtypes.

Short Communication: CD4 Count and HIV RNA Trends for HIV-Associated Lymphoproliferative Disorders in Malawi

Given scarce data from sub-Saharan Africa (SSA), we sought to describe CD4 count and HIV RNA trends over time among patients with HIV-positive lymphoproliferative disorders in Malawi. We prospectively enrolled HIV-positive individuals with pathologically confirmed lymphoproliferative disorders between 2013 and 2016. Chemotherapy was standardized with concurrent antiretroviral therapy (ART). We assessed CD4 count and HIV RNA at baseline and every 6 months for up to 2 years. Of 72 HIV-positive patients, 59 had non-Hodgkin lymphoma (NHL), 5 classical Hodgkin lymphoma (CHL), and 8 multicentric Castleman disease (MCD). Median age was 43 years (range 23-64). Fifty-five patients (76%) were on ART at enrollment for a median 47 months (range 1-387), with median CD4 count of 138 cells/μl (range 2-2,235) and median HIV RNA of 2.2 log10copies/ml (range 0.3-7.3). MCD patients had longer median ART durations, higher median CD4 counts, and lower median HIV RNA at baseline than NHL or CHL patients. CD4 count and HIV RNA steadily improved during follow-up, with different patterns in different histological groups. Twelve-month overall survival (OS) was 55% [95% confidence interval (CI) 42%-66%]. There were trends toward baseline CD4 count <100 cells/μl and HIV RNA >2.0 log10copies/ml being associated with worse OS. However, CD4 count and HIV RNA improvements during follow-up were independent of possible effects on OS. Distribution of HIV-positive lymphoproliferative disorders may change with continued ART scale-up in SSA. Chemotherapy and concurrent ART can lead to good immunological and virological outcomes.

HIV-associated Kaposi sarcoma and related diseases

: The search for the etiologic agent for Kaposi sarcoma led to the discovery of Kaposi sarcoma-associated herpesvirus (KSHV) in 1994. KSHV, also called human herpesvirus-8, has since been shown to be the etiologic agent for several other tumors and diseases, including primary effusion lymphoma (PEL), an extracavitary variant of PEL, KSHV-associated diffuse large B-cell lymphoma, a form of multicentric Castleman disease, and KSHV inflammatory cytokine syndrome. KSHV encodes several genes that interfere with innate and specific immunity, thwart apoptosis, enhance cell proliferation and cytokine production, and promote angiogenesis, and these play important roles in disease pathogenesis. HIV is an important cofactor in Kaposi sarcoma pathogenesis, and widespread use of antiretroviral therapy has reduced Kaposi sarcoma incidence. However, Kaposi sarcoma remains the second most frequent tumor arising in HIV-infected patients in the United States and is particularly common in sub-Saharan Africa. KSHV prevalence varies substantially in different populations. KSHV is secreted in saliva, and public health measures to reduce its spread may help reduce the incidence of KSHV-associated diseases. Although there have been advances in the treatment of Kaposi sarcoma, KSHV-multicentric Castleman disease, and PEL, improved therapies are needed, especially those that are appropriate for Kaposi sarcoma in resource-poor regions.

Kaposi sarcoma herpesvirus-associated cancers and related diseases

PURPOSE OF REVIEW

This review discusses the pathogenesis and recent advances in the management of Kaposi sarcoma herpesvirus (KSHV)-associated diseases.

RECENT FINDINGS

KSHV, a gammaherpesvirus, causes several tumors and related diseases, including Kaposi sarcoma, a form of multicentric Castleman disease (KSHV-MCD), and primary effusion lymphoma. These most often develop in patients infected with human immunodeficiency virus (HIV). KSHV inflammatory cytokine syndrome (KICS) is a newly described syndrome with high mortality that has inflammatory symptoms-like MCD but not the pathologic lymph node findings. KSHV-associated diseases are often associated with dysregulated human interleukin-6, and KSHV encodes a viral interleukin-6, both of which contribute to disease pathogenesis. Treatment of HIV is important in HIV-infected patients. Strategies to prevent KSHV infection may reduce the incidence of these tumors. Pomalidomide, an immunomodulatory agent, has activity in Kaposi sarcoma. Rituximab is active in KSHV-MCD but can cause Kaposi sarcoma exacerbation; rituximab plus liposomal doxorubicin is useful to treat KSHV-MCD patients with concurrent Kaposi sarcoma.

SUMMARY

KSHV is the etiological agents of all forms of Kaposi sarcoma and several other diseases. Strategies employing immunomodulatory agents, cytokine inhibition, and targeting of KSHV-infected cells are areas of active research.

Fever and generalised lymphadenopathy in an HIV-positive patient: a diagnostic challenge

Fever and generalised lymphadenopathy is a common presentation of a variety of diseases and a thorough investigation is often necessary for appropriate diagnosis.We present a 53-year-old male patient admitted with fever, weight loss of 15 kg in 3 months and abdominal discomfort. Examination was only remarkable for axillary and inguinal lymphadenopathy. Blood tests showed normocytic normochromic anaemia, cholestasis and a previously unknown HIV-1 infection with lymphocyte CD4 +count of 239 cells/mm³ and viral load 3.172.370 copies/mL. A body CT scan showed multiple axillary, mediastinal, lumbar, aortic, iliac and pelvic lymphadenopathy as well as hepatosplenomegaly. An excisional biopsy of the left axillary lymphadenopathy was performed and histology ultimately revealed multicentric Castleman's disease associated with Human Herpes Virus-8. After initiation of antiretroviral therapy, rituximab was given and progressive clinical improvement occurred.