Venous thromboembolism in people living with HIV infection (PWH)

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.

Venous Thromboembolism Among People With HIV: Design, Implementation, and Findings of a Centralized Adjudication System in Clinical Care Sites Across the United States

BACKGROUND

People with HIV (PWH) are at increased risk for venous thromboembolism (VTE). We conducted this study to characterize VTE including provoking factors among PWH in the current treatment era.

METHODS

We included PWH with VTE between 2010 and 2020 at 6 sites in the CFAR Network of Integrated Clinical Systems cohort. We ascertained for possible VTE using diagnosis, VTE-related imaging, and VTE-related procedure codes, followed by centralized adjudication of primary data by expert physician reviewers. We evaluated sensitivity and positive predictive value of VTE ascertainment approaches. VTEs were classified by type and anatomic location. Reviewers identified provoking factors such as hospitalizations, infections, and other potential predisposing factors such as smoking.

RESULTS

We identified 557 PWH with adjudicated VTE: 239 (43%) had pulmonary embolism with or without deep venous thrombosis, and 318 (57%) had deep venous thrombosis alone. Ascertainment with clinical diagnoses alone missed 6% of VTEs identified with multiple ascertainment approaches. DVTs not associated with intravenous lines were most often in the proximal lower extremities. Among PWH with VTE, common provoking factors included recent hospitalization (n = 134, 42%), infection (n = 133, 42%), and immobilization/bed rest (n = 78, 25%). Only 57 (10%) PWH had no provoking factor identified. Smoking (46%), HIV viremia (27%), and injection drug use (22%) were also common.

CONCLUSIONS

We conducted a robust adjudication process that demonstrated the benefits of multiple ascertainment approaches followed by adjudication. Provoked VTEs were more common than unprovoked events. Nontraditional and modifiable potential predisposing factors such as viremia and smoking were common.

Selected inflammatory and coagulation biomarkers pre-viral suppression in people with human immunodeficiency virus (HIV) infection without overt cardiovascular disease: Is there a need to redefine reference indices?

BACKGROUND

Human immunodeficiency virus (HIV) infection is prevalent in Africa and causes morbidity and mortality despite antiretroviral therapy (ART). Non-communicable complications of HIV infection include cardiovascular disease (CVD) with thromboses throughout the vascular tree. Ongoing inflammation and endothelial dysfunction in people living with HIV (PLWH) probably contribute significantly to HIV-related CVD.

OBJECTIVES

A systematic review was conducted to inform interpretation of 5 biomarkers commonly measured in PLWH namely interleukin-6 (IL-6), tumour necrosis factor alpha (TNF-α), D-dimers, and soluble intracellular and vascular adhesion molecules-1 (sICAM-1 and sVCAM-1) to attempt to define a range for these values in ART naïve PLWH without overt CVD or additional comorbid diseases.

METHODS

A systematic search was conducted for all studies documenting the levels of the above biomarkers in ART naïve PLWH published on the PubMed database from 1994 to 2020.

RESULTS

The number of publications that reported medians above the assay values was: 4/15 for D-dimer; 0/5 for TNF-α, 8/16 for IL-6, 3/6 for sVCAM-1, and 4/5 for sICAM-1.

CONCLUSION

The clinical utility of biomarkers is reduced by the lack of standardisation of the measurement of these parameters, absence of normal reference indices and the lack of uniformity of study protocols in different research centres. This review supports the ongoing use of D-dimers to predict thrombotic and bleeding events in PLWH since the weighted averages across study assays suggest that the median levels do not exceed the reference range. The role of inflammatory cytokine monitoring and measurement of endothelial adhesion markers is less clear.

Venous thromboembolism in viral diseases: A comprehensive literature review

Venous thromboembolism (VTE) is known to be a common respiratory and/or cardiovascular complication in hospitalized patients with viral infections. Numerous studies have proven human immunodeficiency virus infection to be a prothrombotic condition. An elevated VTE risk has been observed in critically ill H1N1 influenza patients. VTE risk is remarkably higher in patients infected with the Hepatitis C virus in contrast to uninfected subjects. The elevation of D-dimer levels supported the association between Chikungunya and the Zika virus and the rise of clinical VTE risk. Varicella-zoster virus is a risk factor for both cellulitis and the consequent invasive bacterial disease which may take part in thrombotic initiation. Eventually, hospitalized patients infected with the coronavirus disease of 2019 (COVID-19), the cause of the ongoing worldwide pandemic, could mainly suffer from an anomalous risk of coagulation activation with enhanced venous thrombosis events and poor quality clinical course. Although the risk of VTE in nonhospitalized COVID-19 patients is not known yet, there are a large number of guidelines and studies on thromboprophylaxis administration for COVID-19 cases. This study aims to take a detailed look at the effect of viral diseases on VTE, the epidemiology of VTE in viral diseases, and the diagnosis and treatment of VTE.

Map of thrombogenesis in viral infections and viral-driven tumours

Viruses are pathogenic agents responsible for approximately 10% of all human cancers and significantly contribute to the global cancer burden. Until now, eight viruses have been associated with the development of a broad range of malignancies, including solid and haematological tumours. Besides triggering and promoting oncogenesis, viral infections often go hand-in-hand with haemostatic changes, representing a potential risk factor for venous thromboembolism (VTE). Conversely, VTE is a cardiovascular condition that is particularly common among oncological patients, with a detrimental impact on patient prognosis. Despite an association between viral infections and coagulopathies, it is unclear whether viral-driven tumours have a different incidence and prognosis pattern of thromboembolism compared to non-viral-induced tumours. Thus, this review aims to analyse the existing evidence concerning the association of viruses and viral tumours with the occurrence of VTE. Except for hepatitis C virus (HCV) and human immunodeficiency virus (HIV) infection, which are associated with a high risk of VTE, little evidence exists concerning the thrombogenic potential associated with oncoviruses. As for tumours that can be induced by oncoviruses, four levels of VTE risk are observed, with hepatocellular carcinoma (HCC) and gastric carcinoma (GC) associated with the highest risk and nasopharyngeal carcinoma (NPC) associated with the lowest risk. Unfortunately, the incidence of cancer-related VTE according to tumour aetiology is unknown. Given the negative impact of VTE in oncological patients, research is required to better understand the mechanisms underlying blood hypercoagulability in viral-driven tumours to improve VTE management and prognosis assessment in patients diagnosed with these tumours.

Thrombotic thrombocytopenic purpura (TTP) in Human immunodeficiency virus (HIV) infected patients: New twists on an old disease

OBJECTIVE

Investigate the presence of inflammation, endothelial dysfunction and complement activation in patients with HIV-associated thrombotic thrombocytopenic purpura (HIV-TTP) to support the hypothesis that these processes probably contribute to the development of this thrombotic microangiopathy.

DESIGN

A prospective, investigational cohort study of 35 consecutive patients diagnosed with HIV-associated TTP presenting to three academic, tertiary care hospitals in Johannesburg, South Africa over 2 years.

METHODS

The patients with HIV-TTP received therapeutic plasma therapy and supportive treatment. Demographic data, the results of routine investigations and patient outcomes were recorded. Peripheral blood samples were collected prior to and on completion of plasma therapy and the following additional parameters were assessed at both time points: activity of the von Willebrand factor (VWF) cleaving protease, a-disintegrin-and-metalloproteinase-with-thrombospondin-motifs 13 (ADAMTS-13) and the presence of ADAMTS-13 autoantibodies, levels of pro-inflammatory cytokines, interleukin-6 and tumour necrosis factor-alpha, and two endothelial cell adhesion molecules. Complement activation was assessed by sequential measurement of C3 and C4 as well as levels of the complement inhibitor, factor H.

RESULTS

The inflammatory and endothelial activation markers were significantly (P < 0.001) elevated in the cohort of patients prior to plasma therapy compared with levels on discharge. Complement was activated and normalized with therapy. The ADAMTS-13 levels were reduced with significant auto-antibodies to this protease at presentation.

CONCLUSION

Inflammation in HIV mediates endothelial damage and complement activation. This study proposes that these processes are probably contributory to the development of HIV-TTP, which can therefore be characterized in part as a complementopathy, resembling TTP-like syndrome.

Elevated Risk of Venous Thromboembolism in People Living with HIV

Human immunodeficiency virus (HIV) has been generally considered as a highly adaptive and rapidly evolving virus. It still constitutes a major public health problem all over the world despite an effective outcome in the prevention and reversal of the development and prognosis by using antiretroviral therapy. The salient question lies in the more frequent emergence of a series of comorbidities along with the prolongation of the life, which deeply affects the survival in such group. Venous thromboembolism (VTE) has been recognized to be the third most common cardiovascular condition within people living with HIV (PWH). In terms of its mechanism of action, the occurrence of VTE is quite multifactorial and complex in HIV. Prior exploration concerning the etiology of VTE in PWH identifies general, disease-specific, and miscellaneous factors for explaining its occurrence and development. VTE has constituted an important role in PWH and may increase its all-cause mortality. Therefore, it is quite necessary to understand VTE from the following aspects of epidemiology, pathophysiology, molecular mechanisms, and therapeutic interventions so as to balance the risks and benefits of anticoagulation and optimize corresponding treatment.

The Youngbloods. Get Together. Hypercoagulation, Complement, and NET Formation in HIV/SIV Pathogenesis

Chronic, systemic T-cell immune activation and inflammation (IA/INFL) have been reported to be associated with disease progression in persons with HIV (PWH) since the inception of the AIDS pandemic. IA/INFL persist in PWH on antiretroviral therapy (ART), despite complete viral suppression and increases their susceptibility to serious non-AIDS events (SNAEs). Increased IA/INFL also occur during pathogenic SIV infections of macaques, while natural hosts of SIVs that control chronic IA/INFL do not progress to AIDS, despite having persistent high viral replication and severe acute CD4+ T-cell loss. Moreover, natural hosts of SIVs do not present with SNAEs. Multiple mechanisms drive HIV-associated IA/INFL, including the virus itself, persistent gut dysfunction, coinfections (CMV, HCV, HBV), proinflammatory lipids, ART toxicity, comorbidities, and behavioral factors (diet, smoking, and alcohol). Other mechanisms could also significantly contribute to IA/INFL during HIV/SIV infection, notably, a hypercoagulable state, characterized by elevated coagulation biomarkers, including D-dimer and tissue factor, which can accurately identify patients at risk for thromboembolic events and death. Coagulation biomarkers strongly correlate with INFL and predict the risk of SNAE-induced end-organ damage. Meanwhile, the complement system is also involved in the pathogenesis of HIV comorbidities. Despite prolonged viral suppression, PWH on ART have high plasma levels of C3a. HIV/SIV infections also trigger neutrophil extracellular traps (NETs) formation that contribute to the elimination of viral particles and infected CD4+ T-cells. However, as SIV infection progresses, generation of NETs can become excessive, fueling IA/INFL, destruction of multiple immune cells subsets, and microthrombotic events, contributing to further tissue damages and SNAEs. Tackling residual IA/INFL has the potential to improve the clinical course of HIV infection. Therefore, therapeutics targeting new pathways that can fuel IA/INFL such as hypercoagulation, complement activation and excessive formation of NETs might be beneficial for PWH and should be considered and evaluated.

The Role of P-Selectin in COVID-19 Coagulopathy: An Updated Review

In severe COVID-19, which is characterized by blood clots and neutrophil-platelet aggregates in the circulating blood and different tissues, an increased incidence of cardiovascular complications and venous thrombotic events has been reported. The inflammatory storm that characterizes severe infections may act as a driver capable of profoundly disrupting the complex interplay between platelets, endothelium, and leukocytes, thus contributing to the definition of COVID-19-associated coagulopathy. In this frame, P-selectin represents a key molecule expressed on endothelial cells and on activated platelets, and contributes to endothelial activation, leucocyte recruitment, rolling, and tissue migration. Briefly, we describe the current state of knowledge about P-selectin involvement in COVID-19 pathogenesis, its possible use as a severity marker and as a target for host-directed therapeutic intervention.

A rare case of constrictive pericarditis with Budd-Chiari syndrome due to right atrial thrombosis

Patients living with HIV (PLWH) with previous pulmonary tuberculosis, presenting with disproportionate ascites to peripheral congestion, should alert the clinician to consider constrictive pericarditis and Budd–Chiari syndrome (BCS). Constrictive pericarditis is the scarring and loss of the pericardial sac elasticity. The aetiology of constrictive pericarditis varies between developed and developing countries, with infective causes like tuberculosis being significant in South Africa. Budd–Chiari syndrome is a group of disorders characterised by hepatic venous outflow obstruction. The level of obstruction in Budd–Chiari syndrome varies globally. In Asia, South Africa, India, and China, obstruction is predominantly found in the inferior vena cava while in Western countries, hepatic vein obstruction occurs. Patients living with HIV are at increased risk of arterial and venous thromboembolism. The clinician must consider Budd–Chiari syndrome in patients living with HIV presenting with ascites. In patients living with HIV, tuberculosis co-infection has been associated with a higher risk of pericarditis. Both constrictive pericarditis and Budd–Chiari syndrome share a remarkably similar clinical presentation, with ascites and hepatomegaly. There is a dearth of literature on co-existent constrictive pericarditis and Budd–Chiari syndrome. We describe a 31-year-old HIV-infected female, on anti-retroviral therapy (CD4 count 208 cells/uL, undetected viral load), with previous pulmonary tuberculosis, who presented with a 2-month history of abdominal swelling, peripheral oedema, and New York Heart Association grade 4 dyspnoea. Examination revealed an elevated jugular venous pulsation with CV waves, atrial fibrillation, right-sided S3 gallop, pansystolic murmur (3/6) at the left sternal border, tender hepatomegaly, and massive ascites with minimal peripheral oedema. The discordant size of ascites prompted investigations, namely, ultrasound abdomen, echocardiogram, and computed tomography (chest and abdomen). These revealed constrictive pericarditis and Budd–Chiari syndrome with thrombus formation in the right atrium, hepatic vein, and inferior vena cava. She was initiated onto anti-coagulation, anti-tuberculosis therapy and referred for pericardiectomy. Clinicians must maintain a suspicion for constrictive pericarditis and Budd–Chiari syndrome in HIV-infected patients, especially in those with a previous tuberculosis, presenting with features of right heart failure.