Thrombosis and a hypercoagulable state in HIV-infected patients

Inflammation in HIV and Its Impact on Atherosclerotic Cardiovascular Disease

People living with HIV have a 1.5- to 2-fold increased risk of developing cardiovascular disease. Despite treatment with highly effective antiretroviral therapy, people living with HIV have chronic inflammation that makes them susceptible to multiple comorbidities. Several factors, including the HIV reservoir, coinfections, clonal hematopoiesis of indeterminate potential (CHIP), microbial translocation, and antiretroviral therapy, may contribute to the chronic state of inflammation. Within the innate immune system, macrophages harbor latent HIV and are among the prominent immune cells present in atheroma during the progression of atherosclerosis. They secrete inflammatory cytokines such as IL (interleukin)-6 and tumor necrosis-α that stimulate the expression of adhesion molecules on the endothelium. This leads to the recruitment of other immune cells, including cluster of differentiation (CD)8+ and CD4+ T cells, also present in early and late atheroma. As such, cells of the innate and adaptive immune systems contribute to both systemic inflammation and vascular inflammation. On a molecular level, HIV-1 primes the NLRP3 (NLR family pyrin domain containing 3) inflammasome, leading to an increased expression of IL-1β, which is important for cardiovascular outcomes. Moreover, activation of TLRs (toll-like receptors) by HIV, gut microbes, and substance abuse further activates the NLRP3 inflammasome pathway. Finally, HIV proteins such as Nef (negative regulatory factor) can inhibit cholesterol efflux in monocytes and macrophages through direct action on the cholesterol transporter ABCA1 (ATP-binding cassette transporter A1), which promotes the formation of foam cells and the progression of atherosclerotic plaque. Here, we summarize the stages of atherosclerosis in the context of HIV, highlighting the effects of HIV, coinfections, and antiretroviral therapy on cells of the innate and adaptive immune system and describe current and future interventions to reduce residual inflammation and improve cardiovascular outcomes among people living with HIV.

Gut microbial co-metabolite 2-methylbutyrylcarnitine exacerbates thrombosis via binding to and activating integrin α2β1

Thrombosis represents the leading cause of death and disability upon major adverse cardiovascular events (MACEs). Numerous pathological conditions such as COVID-19 and metabolic disorders can lead to a heightened thrombotic risk; however, the underlying mechanisms remain poorly understood. Our study illustrates that 2-methylbutyrylcarnitine (2MBC), a branched-chain acylcarnitine, is accumulated in patients with COVID-19 and in patients with MACEs. 2MBC enhances platelet hyperreactivity and thrombus formation in mice. Mechanistically, 2MBC binds to integrin α2β1 in platelets, potentiating cytosolic phospholipase A2 (cPLA2) activation and platelet hyperresponsiveness. Genetic depletion or pharmacological inhibition of integrin α2β1 largely reverses the pro-thrombotic effects of 2MBC. Notably, 2MBC can be generated in a gut-microbiota-dependent manner, whereas the accumulation of plasma 2MBC and its thrombosis-aggravating effect are largely ameliorated following antibiotic-induced microbial depletion. Our study implicates 2MBC as a metabolite that links gut microbiota dysbiosis to elevated thrombotic risk, providing mechanistic insight and a potential therapeutic strategy for thrombosis.

Pitavastatin in the Prevention of Cardiovascular Disease in People Living with HIV: A Review

HIV is associated with a wide array of pathophysiologic mechanisms that ultimately contribute to mortality. While HIV is traditionally known as a disease that attacks the immune system, it is now established that infection with HIV can cause cardiovascular disease (CVD). Through inflammation, atherogenesis, interactions with antiretroviral therapy/highly-active antiretroviral therapy (ART/HAART), and other mechanisms, HIV is an independent risk factor for the development of CVD. The treatment of the CVD risks associated with HIV is complicated, especially due to interactions with hyperlipidemic drugs and ART/HAART. There is a prompt need for a drug (or drug class) that is known to reduce the risk of CVD, specifically in people living with HIV. Recently, the randomized trial to prevent vascular events in HIV trial evaluated the usage of pitavastatin in preventing major cardiac events in people with HIV, showing a significant reduction in cardiac events among those taking the therapeutic. In this review, we evaluate the mechanisms by which HIV contributes to CVD, and the randomized trial to prevent vascular events in HIV trial, and postulate about future directions of the drug in treating people living with HIV.

Pilot study on the efficacy and safety of berberine in people with metabolic syndrome and human immunodeficiency virus infection

BACKGROUND

Antiretroviral therapy has increased the life expectancy of people living with HIV. However, this increase is not free of comorbidities, and metabolic syndrome is one of the most prevalent. Berberine is an alkaloid nutraceutical that has been shown to ameliorate metabolic disorders such as prediabetes, polycystic ovary syndrome, and non-alcoholic fatty liver disease. However, it has not been tested in HIV infection. Therefore, we conducted a randomized controlled trial to evaluate the efficacy of berberine in improving metabolic syndrome.

METHODS AND RESULTS

In this double-blind, placebo-controlled trial, adults living with HIV under virological suppression and metabolic syndrome received either berberine 500 mg TID or placebo for 20 weeks. The primary outcomes were a composite of weight reduction, insulin resistance decrease, and lipid profile improvement. A total of 43 participants were randomized (22 in the berberine group and 21 in the placebo group); 36 participants completed the follow-up and were analyzed. The berberine group showed a reduction in weight and body mass index, lower insulin resistance, and a reduction in TNF-alpha. The control group had higher total cholesterol, c-LDL, and IL-6 concentration.

CONCLUSION

In people living with HIV under virological suppression, berberine was safe and improves clinical and biochemical components of metabolic syndrome. However, further studies with more participants and longer intervention periods need to be explored.

A Diagnostic Pitfall of Transthoracic Echocardiography: A Case of a Missed Large Mitral Valve Thrombus in the Setting of Suspected Nonbacterial Thrombotic Endocarditis

Transthoracic echocardiography (TTE) is frequently utilized in the initial evaluation of cardioembolic stroke. However, the diagnostic utility of TTE is often operator-dependent, and in conjunction with anatomical limitations, there is a range of sensitivities reported in the literature specifically in the evaluation of nonbacterial thrombotic endocarditis (NBTE). Thus, relying on TTE findings to rule out NBTE in the setting of cardioembolic stroke evaluation can lead to misdiagnosis in the absence of confirmatory transesophageal echocardiography (TEE). We present a case of a 67-year-old female with a past medical history of hypertension, diabetes mellitus, human immunodeficiency virus (HIV), and recurrent ischemic strokes who was referred by her neurologist for TEE. Despite an initial TTE with a bubble study showing no evidence of intra-atrial septum, left ventricular thrombus, or any valvular pathology, there remained high suspicion of a cardioembolic source due to the bi-hemispheric presentation of the patient's previous strokes. Prior electrocardiography and cardiac event monitor showed normal sinus rhythm. Her TEE revealed a large, dense thrombus measuring 1.0 x 0.8 centimeters involving the anterior mitral valve leaflet with associated moderate mitral regurgitation. The patient was placed on systemic anticoagulation and discharged home with outpatient follow-up with cardiology. Our case highlights the diagnostic pitfalls of TTE use in the evaluation of cardioembolic stroke with a particular emphasis on NBTE in addition to discussing the rationale for follow-up TEE when TTE is otherwise unrevealing.

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.

Tobacco smoking and binge alcohol use are associated with incident venous thromboembolism in an HIV cohort

BACKGROUND

People with HIV (PWH) are at increased risk of cardiovascular comorbidities and substance use is a potential predisposing factor. We evaluated associations of tobacco smoking and alcohol use with venous thromboembolism (VTE) in PWH.

METHODS

We assessed incident, centrally adjudicated VTE among 12 957 PWH within the Centers for AIDS Research Network of Integrated Clinical Systems (CNICS) cohort between January 2009 and December 2018. Using separate Cox proportional hazards models, we evaluated associations of time-updated alcohol and cigarette use with VTE, adjusting for demographic and clinical characteristics. Smoking was evaluated as pack-years and never, former, or current use with current cigarettes per day. Alcohol use was parameterized using categorical and continuous alcohol use score, frequency of use, and binge frequency.

RESULTS

During a median of 3.6 years of follow-up, 213 PWH developed a VTE. One-third of PWH reported binge drinking and 40% reported currently smoking. In adjusted analyses, risk of VTE was increased among both current (HR: 1.44, 95% CI: 1.02-2.03) and former (HR: 1.44, 95% CI: 0.99-2.07) smokers compared to PWH who never smoked. Additionally, total pack-years among ever-smokers (HR: 1.10 per 5 pack-years; 95% CI: 1.03-1.18) was associated with incident VTE in a dose-dependent manner. Frequency of binge drinking was associated with incident VTE (HR: 1.30 per 7 days/month, 95% CI: 1.11-1.52); however, alcohol use frequency was not. Severity of alcohol use was not significantly associated with VTE.

CONCLUSIONS

Current smoking and pack-year smoking history were dose-dependently associated with incident VTE among PWH in CNICS. Binge drinking was also associated with VTE. Interventions for smoking and binge drinking may decrease VTE risk among PWH.

Dysregulation of Protein S in COVID-19

Coronavirus Disease 2019 (COVID-19) has been widely associated with increased thrombotic risk, with many different proposed mechanisms. One such mechanism is acquired deficiency of protein S (PS), a plasma protein that regulates coagulation and inflammatory processes, including complement activation and efferocytosis. Acquired PS deficiency is common in patients with severe viral infections and has been reported in multiple studies of COVID-19. This deficiency may be caused by consumption, degradation, or clearance of the protein, by decreased synthesis, or by binding of PS to other plasma proteins, which block its anticoagulant activity. Here, we review the functions of PS, the evidence of acquired PS deficiency in COVID-19 patients, the potential mechanisms of PS deficiency, and the evidence that those mechanisms may be occurring in COVID-19.

Total Plasma Protein S Is a Prothrombotic Marker in People Living With HIV

BACKGROUND

HIV-1 infection is associated with multiple procoagulant changes and increased thrombotic risk. Possible mechanisms for this risk include heigthened expression of procoagulant tissue factor (TF) on circulating monocytes, extracellular vesicles, and viral particles and/or acquired deficiency of protein S (PS), a critical cofactor for the anticoagulant protein C (PC). PS deficiency occurs in up to 76% of people living with HIV-1 (PLWH). As increased ex vivo plasma thrombin generation is a strong predictor of mortality, we investigated whether PS and plasma TF are associated with plasma thrombin generation.

METHODS

We analyzed plasma samples from 9 healthy controls, 17 PLWH on first diagnosis (naive), and 13 PLWH on antiretroviral therapy (ART). Plasma thrombin generation, total and free PS, PC, C4b-binding protein, and TF activity were measured.

RESULTS

We determined that the plasma thrombin generation assay is insensitive to PS, because of a lack of PC activation, and developed a modified PS-sensitive assay. Total plasma PS was reduced in 58% of the naive and 38% of the ART-treated PLWH samples and correlated with increased thrombin generation in the modified assay. Conversely, plasma TF was not increased in our patient population, suggesting that it does not significantly contribute to ex vivo plasma thrombin generation.

CONCLUSION

These data suggest that reduced total plasma PS contributes to the thrombotic risk associated with HIV-1 infection and can serve as a prothrombotic biomarker. In addition, our refined thrombin generation assay offers a more sensitive tool to assess the functional consequences of acquired PS deficiency in PLWH.

Coagulation Parameters in Human Immunodeficiency Virus Infected Patients: A Systematic Review and Meta-Analysis

Background

Coagulation abnormalities are common complications of human immunodeficiency virus (HIV) infection. Highly active antiretroviral treatment (HAART) decreased the mortality of HIV but increased coagulopathies. HIV-related thrombocytopenia, prolonged prothrombin time (PT), activated partial thromboplastin time (APTT), and high D-dimer level commonly manifested in patients with HIV. Thus, this study is aimed to compare coagulation parameters of HAART-treated and HAART-naïve HIV-infected patients with HIV-seronegative controls.

Methods

A systematic literature search was conducted using the databases PubMed/MEDLINE, Embase, Web of Science, and Google Scholar of studies published until July 2021. The primary outcome of interest was determining the pooled mean difference of coagulation parameters between HIV-infected patients and seronegative controls. The Joana Briggs Institute (JBI) critical appraisal tool was used for quality appraisal. Statistical analyses were performed using Stata11.0 software. The statistical results were expressed as the effect measured by standardized mean difference (SMD) with their related 95% confidence interval (CI).

Results

A total of 7,498 participants (1,144 HAART-naïve patients and 2,270 HAART-treated HIV-infected patients and 3,584 HIV-seronegative controls) from 18 studies were included. HIV-infected patients (both on HAART and HAART-naive) exhibited significantly higher levels of PT than HIV-seronegative controls (SMD = 0.66; 95% CI: 0.53–0.80 and SMD = 1.13; 95% CI: 0.60–2.0, respectively). The value of APTT was significantly higher in patients with HIV on HAART than in seronegative controls. However, the values of PLT count, APTT, and fibrinogen level were significantly higher in seronegative controls. Besides, the level of fibrinogen was significantly higher in HAART-treated than treatment-naïve patients (SMD = 0.32; 95%CI: 0.08, 0.57). Moreover, the level of APTT and PT had no statistical difference between HAART and HAART-naïve HIV-infected patients.

Conclusions

This study identified that HIV-infected patients are more likely to develop coagulation abnormalities than HIV-seronegative controls. Therefore, coagulation parameters should be assessed regularly to prevent and monitor coagulation disorders in HIV-infected patients.

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.

International Normalized Ratio (INR) Increases amongst Two Patients Living with HIV on Warfarin after Being Switched from a Nevirapine to a Dolutegravir-Based Antiretroviral Regimen

The increased use of dolutegravir-based regimens in the treatment of HIV is unmasking drug interactions, particularly in patients who were previously on nevirapine. Nevirapine is an enzyme inducer and increases the dosing requirements for cytochrome P450 enzyme substrates including warfarin. Upon discontinuing nevirapine, close monitoring of drugs with narrow therapeutic indices is paramount since dosing requirements may significantly reduce, increasing the probability of toxicity development. We present two cases describing interactions experienced by patients living with HIV, while transitioning from nevirapine to dolutegravir-based HIV regimens. The first case describes a 70-year-old man living with HIV and diabetes, while the second case describes a 60-year-old woman living with HIV. They were diagnosed with unprovoked deep vein thrombi, and while receiving treatment with warfarin, their HIV medication regimen was changed from lamivudine, zidovudine, nevirapine, and septrin to lamivudine, tenofovir, dolutegravir, and septrin. During the weeks following this switch, warfarin requirements decreased resulting in supratherapeutic INRs. With the continued promotion of dolutegravir-based HIV regimens as the preferred option for the treatment of HIV in President's Emergency Plan for AIDS Relief (PEPFAR) supported HIV treatment programs in Africa, clinicians must be aware of the potentially life-threatening consequences of switching antiretroviral regimens. It is hoped that a greater awareness of this potential side effect could lead to increased monitoring and prevention of the consequences of drug interactions.

Haematological parameters and coagulation in umbilical cord blood following COVID-19 infection in pregnancy

Objective

The aim of this study was to evaluate infants, born to women with SARS-CoV-2 detected during pregnancy, for evidence of haematological abnormalities or hypercoagulability in umbilical cord blood.

Study design

This was a prospective observational case-control study of infants born to women who had SARS-CoV-2 RNA detected by PCR at any time during their pregnancy (n = 15). The study was carried out in a Tertiary University Maternity Hospital (8,500 deliveries/year) in Ireland. This study was approved by the Hospital Research Ethics Committee and written consent was obtained. Umbilical cord blood samples were collected at delivery, full blood count and Calibrated Automated Thrombography were performed. Demographics and clinical outcomes were recorded. Healthy term infants, previously recruited as controls to a larger study prior to the outbreak of COVID-19, were the historical control population (n = 10).

Results

Infants born to women with SARS-CoV-2 had similar growth parameters (birth weight 3600 g v 3680 g, p = 0.83) and clinical outcomes to healthy controls, such as need for resuscitation at birth (2 (13.3%) v 1 (10%), p = 1.0) and NICU admission (1 (6.7%) v 2 (20%), p = 0.54). Haematological parameters (Haemoglobin, platelet, white cell and lymphocyte counts) in the COVID-19 group were all within normal neonatal reference ranges. Calibrated Automated Thrombography revealed no differences in any thrombin generation parameters (lag time (p = 0.92), endogenous thrombin potential (p = 0.24), peak thrombin (p = 0.44), time to peak thrombin (p = 0.94)) between the two groups.

Conclusion

In this prospective study including eligible cases in a very large population of approximately 1500 women, there was no evidence of derangement of the haematological parameters or hypercoagulability in umbilical cord blood due to COVID-19. Further research is required to investigate the pathological placental changes, particularly COVID-19 placentitis and the impact of different strains of SARS-CoV-2 (particularly the B.1.1.7 and the emerging Delta variant) and the severity and timing of infection on the developing fetus.

Superior Sagittal Sinus Thrombosis in a Young, Immunocompetent HIV Patient: A Rare Case

Cerebral venous thrombosis is a rare form of stroke that can present with various clinical features. In addition, it can present with nonspecific neurological features, and initial computed tomography (CT) cannot rule it out even if negative. Human immunodeficiency virus (HIV) infection is a hypercoagulable state; however, it is not much discussed. Here, we present a case of a 24-year-old immunocompetent female who presented with acute meningeal symptoms. She was managed as a case of an opportunistic central nervous system infection at initial presentation, which did not resolve her symptoms completely. Later, however, cerebral thrombosis was diagnosed, and she improved symptomatically on anticoagulants.

The Role of HIV Infection in the Pathophysiology of Gestational Diabetes Mellitus and Hypertensive Disorders of Pregnancy

Purpose of the Review: The main objective of this study is to investigate mechanisms associated with gestational diabetes mellitus (GDM) and hypertensive disorders of pregnancy (HDP) in HIV infected pregnant women by looking how placental hormones such as (progesterone and prolactin) and basic haemostatic parameters are regulated in HIV infected pregnancies.

Recent Findings: HIV/AIDS are a major global obstetric health burden that lead to increased rate of morbidity and mortality. HIV/AIDS has been associated with the pathophysiology of GDM and HDP. Increased risk of GDM due to highly active antiretroviral therapy (HAART) usage has been reported in HIV infected pregnancies, which causes insulin resistance in both pregnant and non-pregnant individuals. HAART is a medication used for lowering maternal antepartum viral load and pre-exposure and post-exposure prophylaxis of the infant. In pregnant women, HAART induces diabetogenic effect by causing dysregulation of placental hormones such as (progesterone and prolactin) and predispose HIV infected women to GDM. In addition to HIV/AIDS and GDM, Studies have indicated that HIV infection causes haemostatic abnormalities such as hematological disorder, deregulated haematopoiesis process and the coagulation process which results in HDP.

Summary: This study will help on improving therapeutic management and understanding of the pathophysiology of GDM and HDP in the absence as well as in the presence of HIV infection by reviewing studies reporting on these mechanism.

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.

Identification of two different coagulation phenotypes in people living with HIV with undetectable viral replication

Altered coagulation has been reported in people living with HIV (PLWH) with ongoing viral replication and may predispose to cardiovascular diseases. However, less is known about coagulation in PLWH with undetectable viral replication. In a cross-sectional observational study, we investigated whether HIV infection with undetectable viral replication is independently associated with activated partial thromboplastin time (APTT) and coagulation factor II-VII-X concentrations out of reference. Logistic regression analyses were used to assess the association of HIV infection with APTT and coagulation factor II-VII-X, after adjusting for age, sex, smoking status, alcohol consumption, BMI, diabetes and hsCRP. 936 PLWH with undetectable viral replication from the Copenhagen Co-morbidity in HIV infection study (COCOMO-study) and 2955 uninfected controls were included. Higher prevalence of short APTT was found in PLWH compared to controls (13.5% vs. 7.6%, P < 0.001). Furthermore, higher prevalence of low coagulation factor II-VII-X was found in PLWH than in controls (9.6% vs. 7.4%, P = 0.022). HIV was independently associated with short APTT (adjusted odds ratio (aOR) 2.3 (95% CI 1.7-2.9), P < 0.001) and low coagulation factor II-VII-X (aOR 1.4 (95% CI 1.0-1.9), P = 0.046). Few participants among PLWH and controls had both short APTT and low coagulation factor II-VII-X, 2.1% vs. 0.8%, respectively. We found evidence of both procoagulant (short APTT) and anticoagulant (low coagulation factor II-VII-X) alterations in PLWH with undetectable viral replication, and our findings suggest that two different coagulation phenotypes exist in participants with treated HIV infection.

Systemic Inflammation Associated with Immune Reconstitution Inflammatory Syndrome in Persons Living with HIV

Antiretroviral therapy (ART) has represented a major advancement in the care of people living with HIV (PLWHH), resulting in significant reductions in morbidity and mortality through immune reconstitution and attenuation of homeostatic disruption. Importantly, restoration of immune function in PLWH with opportunistic infections occasionally leads to an intense and uncontrolled cytokine storm following ART initiation known as immune reconstitution inflammatory syndrome (IRIS). IRIS occurrence is associated with the severe and rapid clinical deterioration that results in significant morbidity and mortality. Here, we detail the determinants underlying IRIS development in PLWH, compiling the available knowledge in the field to highlight details of the inflammatory responses in IRIS associated with the most commonly reported opportunistic pathogens. This review also highlights gaps in the understanding of IRIS pathogenesis and summarizes therapeutic strategies that have been used for IRIS.

Stroke in critical COVID-19 patients: a cautionary tale from the frontlines

INTRODUCTION

Although Coronavirus Disease 2019 (COVID-19) is primarily a disease of the respiratory system in its transmission and clinical manifestations, physicians have also reported a tropism toward the nervous system.

METHODS

Neurological symptoms can occur as one of many systemic manifestations of a critical form of the disease or in isolation as the predominant presenting complaint.

RESULTS

We report a series of 6 patients who suffered significant cerebrovascular accidents while being treated for critical COVID-19 in the intensive care units of a quaternary care hospital in New York's Hudson valley.

CONCLUSIONS

This series demonstrates how a relatively rare but catastrophic neurological complication can occur in patients with COVID-19 while they are being managed for their more common problems such as respiratory and renal failure.

Extracellular Vesicle-Related Thrombosis in Viral Infection

Although the outcomes of viral infectious diseases are remarkably varied, most infections cause acute diseases after a short period. Novel coronavirus disease 2019, which recently spread worldwide, is no exception. Extracellular vesicles (EVs) are small circulating membrane-enclosed entities shed from the cell surface in response to cell activation or apoptosis. EVs transport various kinds of bioactive molecules between cells, including functional RNAs, such as viral RNAs and proteins. Therefore, when EVs are at high levels, changes in cell activation, inflammation, angioplasty and transportation suggest that EVs are associated with various diseases. Clinical research on EVs includes studies on the coagulatory system. In particular, abnormal enhancement of the coagulatory system through EVs can cause thrombosis. In this review, we address the functions of EVs, thrombosis, and their involvement in viral infection.

Increasing procoagulant activity of circulating microparticles in patients living with HIV

OBJECTIVES

HIV-infected individuals are at higher risk of non-AIDS diseases associated with procoagulant status. Microparticles are elevated in disorders associated with thrombosis (e.g., cardiovascular diseases). We investigated the association between microparticle levels in untreated and treated HIV-infected subjects, and determined the association with immune status, viral replication, and duration of antiretroviral therapy.

PATIENTS AND METHODS

We included 144 HIV-infected subjects, including 123 on antiretroviral therapy (ART) and 21 before treatment initiation. A control group of 40 HIV-negative healthy adults matched for age and sex was used for comparison of microparticle levels. Treated subjects were divided into five groups depending on the period of antiretroviral exposure. Statistically significant differences were determined by Kruskal-Wallis test and Chi² test. The relation between microparticles and other parameters was assessed using Spearman's coefficient of correlation.

RESULTS

Microparticle levels were significantly higher in treated and untreated HIV-infected subjects than in non-HIV-infected controls (P<0.001). The microparticle level was similar between the groups on treatment (P=0.913). No association between the microparticle level and CD4+ count, CD4+/CD8+ ratio, number of HIV-1 RNA copies, or duration of exposure to antiretroviral treatment was observed.

CONCLUSION

Increased levels of microparticles may be due to processes independent of viral replication and CD4+ cell count, and microparticle release might persist even during viral suppression by antiretroviral treatment. Elevated microparticle levels might occur in response to other triggers.

Clinical features, risk factors, and outcome of cerebral venous thrombosis in Tehran, Iran

Introduction:

Despite increasing the use of magnetic resonance imaging (MRI), cerebral venous sinus thrombosis (CVST) has remained an under-diagnosed condition. In this study, characteristics and frequency of various risk factors of CVST patients in a tertiary referral hospital were closely assessed.

Methods:

Patients with an unequivocal diagnosis of CVST confirmed by MRI and magnetic resonance venography during 6 years of the study were included. All data from the onset of symptoms regarding clinical signs and symptoms, hospital admission, seasonal distribution, medical and drug history, thrombophilic profile, D-dimer, neuroimaging, cerebrospinal fluid findings, mortality, and outcome were collected and closely analyzed.

Result:

A total of 53 patients with female to male ratio of 3.07 and mean age of 33.7 years were included in the study. Headache and papilledema were the most frequent clinical features (44 and 36 patients, respectively). An underlying disease (diagnosed previously or after admission) was the most common identified risk factor for CVST in both females and males (21 patients). A total of 15 women used the oral contraceptive pill (OCP) where 12 of them had simultaneously other predisposing factors. Overall, 19 patients (36%) had more than one contributing factor. D-dimer had a sensitivity of 71.4% in CVST patients. The mortality of patients in this study was 3.7% (n = 2). Focal neurologic deficit and multicranial nerve palsy were associated with poor outcome which defined as death, recurrence, and massive intracranial hemorrhage due to anticoagulation (P = 0.050 and 0.004, respectively).

Conclusion:

Unlike most of the CVST studies in which OCP was the main factor; in this study, an underlying disease was the most identified cause. Considering the high probability of multiple risk factors in CVST that was shown by this study, appropriate work up should be noted to uncover them.

Completion of the Updated Caprini Risk Assessment Model (2013 Version)

The Caprini risk assessment model (RAM) has been validated in over 250 000 patients in more than 100 clinical trials worldwide. Ultimately, appropriate treatment options are dependent on precise completion of the Caprini RAM. As the numerical score increases, the clinical venous thromboembolism rate rises exponentially in every patient group where it has been properly tested. The 2013 Caprini RAM was completed by specially trained medical students via review of the presurgical assessment history, medical clearances, and medical consults. The Caprini RAM was completed for every participant both preoperatively and predischarge to ensure that any changes in the patient’s postoperative course were captured by the tool. This process led to the development of completion guidelines to ensure consistency and accuracy of scoring. The 2013 Caprini scoring system provides a consistent, thorough, and efficacious method for risk stratification and selection of prophylaxis for the prevention of venous thrombosis.

Venous thromboembolism prophylaxis using the Caprini score

Venous thromboembolism (VTE) including pulmonary embolism (PE) and deep vein thrombosis (DVT) is one of the leading causes of preventable cardiovascular disease in the United States (US) and is the number one preventable cause of death following a surgical procedure. Post-operative VTE is associated with multiple short and long-term complications. We will focus on reviewing the many faces of VTE in detail as they represent common challenging scenarios in clinical practice.

Prothrombotic state in HIV: A study on protein C, protein S, homocysteine and correlation with CD4 counts

Introduction

Human immunodeficiency virus (HIV) may result in variable haematological manifestations. Thrombotic events are more common among HIV-infected persons than the general population, possibly due to the increased inflammatory/hypercoagulable state and presence of concurrent comorbidities.

Aims and Objectives

(1) Screen for coagulation abnormalities in HIV-infected patients. (2) Detect certain prothrombotic factors such as deficiency of protein C and protein S and elevation of homocysteine as possible precursors of coagulation defects in HIV patients. (3) Correlation of coagulation abnormalities with CD4 counts.

Methods

A pilot study of 1-year duration conducted in the Department of Pathology in collaboration with ART centre, KGMU Lucknow. All diagnosed HIV-seropositive patients (n = 30) who were not taking Vitamin K, antithrombotic and antiplatelet drugs including aspirin, oral contraceptives and not having known protein C/S deficiency were included in the present study as cases. Apart from this, 30 age- and sex-matched healthy individuals were also included in the present study. Assessment of the bleeding time, prothrombin time and activated partial thromboplastin time, complete blood count was done. Protein C and S were measured by calorimetric assay. Serum homocysteine was measured by the semi-automated method. CD4 count was done by flow cytometry.

Results

The findings of the present study suggest a relationship between HIV, its complications and thrombosis. The HIV-seropositive patients have reduced levels of haemoglobin, CD4 counts, platelet counts, mean platelet volume, protein C and S activity as compared to the healthy individuals. Thrombophilic abnormality in the form of hyperhomocysteinaemia is more frequent in HIV-infected patients. All these parameters have a definite correlation with CD4 count.

Embolizing Massive Right Atrial Thrombus in a HIV-Infected Patient

The risk of thromboembolism is increased when associated with the human immunodeficiency viral (HIV) infection. Various factors are involved in promoting thrombosis, and the presence of a patent foramen ovale augments the potential for a paradoxical embolism. We describe the case of a 56-year-old man receiving antiretroviral therapy with features of right heart failure and pulmonary embolism. Due to the high incidence of life-threatening thromboembolism in the HIV-infected group, the need for long-term anticoagulation has to be evaluated.

Basic Coagulation Parameters among Human Immunodeficiency Virus-Infected Adults in Gondar, Northwest Ethiopia: A Comparative Cross-Sectional Study

Objective

We aimed at assessing the basic coagulation parameters of HIV-infected adults at the University of Gondar Hospital antiretroviral therapy clinic.

Methods

A comparative cross-sectional study was conducted from February to May 2017. A total of 300 study participants, consisting of 100 HAART-naïve HIV-infected adults, 100 HIV-infected adults who were taking HAART, and 100 HIV-seronegative apparently healthy adults, were included. Basic coagulation functional assays such as PT, APTT, and INR were determined by coagulation analyzer. CD4 cells and platelet count were analyzed by FACS count and SYSMEX K-21N automated analyzer, respectively. The data were entered, cleaned, and edited using Epi Info version 7 and analyzed using SPSS version 20. Kruskal-Wallis H, Dunn-Bonferroni pairwise comparison test, and Spearman's rank-order correlation analysis were used for inferential statistics. The results were expressed by a median and presented in tables. P value < 0.05 was considered as statistically significant.

Results

PT, APTT, and INR were significantly higher, whereas platelet count was significantly lower in HIV-infected adults (both who were taking HAART and HAART-naïve) than HIV-seronegative adults (P < 0.001). PT and INR were significantly higher, and platelet count was significantly lower in HAART-naïve HIV-infected adults than HIV-infected adults who were taking HAART. In Spearman's rank-order correlation analysis, APTT has shown a significant negative correlation with a CD4 count in HAART-naïve HIV-infected adults.

Conclusion

HIV-infected adults are more likely to develop coagulation abnormality than HIV-seronegative subjects. Coagulation parameters need to be checked regularly to monitor coagulation disorders in HIV-infected adults.

Preliminary Data From the Study of Coagulative Profile of HIV Infected Individuals Suggest a Role For Point Mutations in the Gene in Protein S Deficiency in Individuals Undergoing Highly Antiretroviral Therapy

Background:

HIV infection is a known prothrombotic condition but factors involved are still controversial. A role for antiretrovirals, especially protease inhibitors, was advocated.

Objectives:

The study aimed to analyze the levels of anticoagulant proteins in virally suppressed HIV-infected subjects treated with different anti-retroviral regimens.

Materials and Methods:

Forty-four patients were included in the study. C and PS, D-Dimers and Fibrinogen levels were determined as well as APC-resistance. PROS1 gene was sequenced in a group of patient.

Results:

Twelve of the 44 subjects (27%) showed reduced levels of PS, while lower levels of PC were found only in 2 patients (4,5%). No difference in the mean values of PC and PS was found stratifying the study population by antiretroviral regimen administrated (p>0.05).

Three patients had higher levels of D-Dimer concentrations and in two of these patients, an association between higher D-Dimer values and lower levels of PS was observed; but however no correlation was found by statistical analysis.

PROS1 gene analysis was performed in 26 of the 44 HIV-1 patients and the subjects with low levels of PS had mutation in the fifteen exon of PROS 1 gene. While among individuals with normal levels, this mutation was observed only in 8/18 (44%) of the cases (p=0,0072).

Conclusion:

The majority of patients with low PS levels also had mutations in the fifteen exon of PROS 1 gene. Genetic determinants, deserving further investigations, rather than antiretrovirals might cause PS deficiency in HIV-1 positive patients.

Prevalence of lower limb deep venous thrombosis among adult HIV positive patients attending an outpatient clinic at Mulago Hospital

Background

Deep venous thrombosis (DVT) and its major complication pulmonary embolism (PE) are collectively known as venous thromboembolism. In Uganda, the prevalence of DVT among HIV patients has not been previously published. The aim of the study was to determine the prevalence and sonographic features of lower limb deep venous thrombosis among HIV positive patients on anti-retroviral treatment (ART).

Methods

This was a cross sectional study in which HIV positive patients on ART were recruited from an out-patient HIV clinic at Mulago National Referral Hospital. Patients were randomly selected and enrolled until a sample size of 384 was reached. Study participants underwent compression and Doppler ultrasound studies of both lower limb deep veins using Medison Sonoacer7 ultrasound machine.

Resuts

We found a prevalence of DVT of 9.1% (35 of 384 participants) among HIV patients on ART. The prevalence of latent (asymptomatic) DVT was 2.3%. Among 35 patients with DVT, 42.8% had chronic DVT; 31.1% had acute DVT and the rest had latent DVT. Among the risk factors, the odds of occurrence of DVT among patients with prolonged immobility were 4.81 times as high as in those with no prolonged immobility (p = 0.023; OR = 4.81; 95% CI 1.25–18.62). Treatment with second line anti-retroviral therapy (ART) including protease inhibitors (PIs) was associated with higher odds of DVT occurrence compared with first line ART (p = 0.020; OR = 2.38; 95% CI 1.14–4.97). The odds of DVT occurrence in patients with a lower CD4 count (< 200 cells/µl) were 5.36 times as high as in patients with CD4 counts above 500 cells/µl (p = 0.008). About 48.6% patients with DVT had a low risk according to Well’s score.

Conclusion

DVT was shown in nearly 10% of HIV patients attending an out-patient clinic in an urban setting in Uganda. Risk factors included protease inhibitors in their ART regimen, prolonged immobility, and low CD4 count (< 200 cells/µl). Clinicians should have a low threshold for performing lower limb Doppler ultrasound scan examination on infected HIV patients on ART who are symptomatic for DVT. Therefore, clinicians should consider anti-coagulant prophylaxis and lower deep venous ultrasound screening of patients who are on second line ART regimen with low CD4 cell counts and/or with prolonged immobility or hormonal contraception.

Upper limb ischaemia: a South African single-centre experience

OBJECTIVE

The aims of this study were to report on our experience with upper limb ischaemia (ULI), to define the pattern and distribution of disease, describe key demographic features and report on conventional clinical outcomes.

METHODS

This was a single-centre, retrospective, descriptive study. All patients (n = 64) who underwent a surgical intervention for ULI over a 12-year study period were included. Findings were analysed and compared with the current literature.

RESULTS

A male:female ratio of 0.60 was reported. Two major subgroups of patients were identified. The patients in the thrombo-embolic subgroup (n = 30) were notably younger than expected (mean age 55 years) compared to those in the atherosclerotic occlusive disease subgroup (n = 12, mean age 57 years). Presentation overall was generally late, with 8.6% of acute ULI and 48.3% of chronic ULI patients presenting with irreversible ischaemia and tissue loss, respectively. Thrombo-embolism was the dominant vascular pathology reported in this case series (47%). Ninety-five procedures were performed in 64 patients (89 open, six endovascular). Peri-operative (30-day) mortality rate was 7.8%. Systemic and procedure-related complications were observed in 13 and 23%, respectively. The overall major amputation rate was 10.9%. Adherence to follow up was poor (51% at six months).

CONCLUSION

Although few firm conclusions could be drawn, this review has expanded our overall perspective of ULI, specific to the population we serve. Collaboration between African vascular units should be encouraged in an attempt to further define the pattern of ULI by identifying distinct geographical confounders.

HIV and coronary disease - When secondary prevention is insufficient

Highly active antiretroviral therapy (HAART) has created a new paradigm for human immunodeficiency virus (HIV)-infected patients, but their increased risk for coronary disease is well documented. We present the case of a 57-year-old man, co-infected with HIV-2 and hepatitis B virus, adequately controlled and with insulin-treated type 2 diabetes and dyslipidemia, who was admitted with non-ST elevation acute myocardial infarction. Coronary angiography performed on day four of hospital stay documented two-vessel disease (mid segment of the right coronary artery [RCA, 90% stenosis] and the first marginal). Two drug-eluting stents were successfully implanted. The patient was discharged under dual antiplatelet therapy (aspirin 100 mg/day and clopidogrel 75 mg/day) and standard coronary artery disease medication. He was admitted to the emergency room four hours after discharge with chest pain radiating to the left arm and inferior ST-segment elevation myocardial infarction was diagnosed. Coronary angiography was performed within one hour and documented thrombosis of both stents. Optical coherence tomography revealed good apposition of the stent in the RCA, with intrastent thrombus. Angioplasty was performed, with a good outcome. The acute stent thrombosis might be explained by the thrombotic potential of HIV infection and diabetes. There are no specific guidelines regarding HAART in secondary prevention of acute coronary syndromes. A multidisciplinary approach is essential for optimal management of these patients.

Revisiting a quarter of a century of simian immunodeficiency virus (SIV)-associated cardiovascular diseases at the German Primate Center

Human immunodeficiency virus (HIV) comorbidities have become clinically more important due to antiretroviral therapy. Although therapy increases life expectancy, it does not completely suppress immune activation and its associated complications. The simian immunodeficiency virus (SIV)-infected rhesus macaque (Macaca mulatta) represents a valuable model for the investigation of SIV-associated diseases. Although cardiovascular (CV) changes are common in HIV-infected patients, there are only a few reports on the incidence of CV findings in SIV-infected animals. In addition, potential associations between pathohistological findings and hematological parameters are still unclear.

We therefore conducted a retrospective analysis of 195 SIV-infected rhesus macaques that were euthanized with AIDS-related symptoms at the German Primate Center, Goettingen, over a 25-year period. Pathological findings were correlated with hematological data.

The main findings included myocarditis (12.8 %), endocarditis (9.7 %), and arteriopathy (10.3 %) in various organs. Thrombocytopenia occurred more frequently in macaques with endocarditis or arteriopathy than in macaques without CV disease (80 % in animals with endocarditis, 60 % in animals with arteriopathy, p<0.0001 and p=0.0016, respectively).

Further investigations of the interaction between coagulation markers, proinflammatory cytokines, and biomarkers associated with endothelial dysfunction (e.g., D-dimers) and histological data (vascular wall structure) may unravel the mechanisms underlying HIV/SIV-associated CV comorbidities.

Immune activation and HIV-specific T cell responses are modulated by a cyclooxygenase-2 inhibitor in untreated HIV-infected individuals: An exploratory clinical trial

Pathologically elevated immune activation and inflammation contribute to HIV disease progression and immunodeficiency, potentially mediated by elevated levels of prostaglandin E₂, which suppress HIV-specific T cell responses. We have previously shown that a high dose of the cyclooxygenase-2 inhibitor celecoxib can reduce HIV-associated immune activation and improve IgG responses to T cell-dependent vaccines. In this follow-up study, we included 56 HIV-infected adults, 28 antiretroviral therapy (ART)-naïve and 28 on ART with undetectable plasma viremia but CD4 counts below 500 cells/μL. Patients in each of the two study groups were randomized to receive 90 mg qd of the cyclooxygenase-2 inhibitor etoricoxib for six months, two weeks or to a control arm, respectively. T cell activation status, HIV Gag-specific T cell responses and plasma inflammatory markers, tryptophan metabolism and thrombin generation were analyzed at baseline and after four months. In addition, patients received tetanus toxoid, conjugated pneumococcal and seasonal influenza vaccines, to which IgG responses were determined after four weeks. In ART-naïve patients, etoricoxib reduced the density of the activation marker CD38 in multiple CD8⁺ T cell subsets, improved Gag-specific T cell responses, and reduced in vitro plasma thrombin generation, while no effects were seen on plasma markers of inflammation or tryptophan metabolism. No significant immunological effects of etoricoxib were observed in ART-treated patients. Patients receiving long-term etoricoxib treatment had poorer tetanus toxoid and conjugated pneumococcal vaccine responses than those receiving short-course etoricoxib. Cyclooxygenase-2 inhibitors may attenuate harmful immune activation in HIV-infected patients without access to ART.

The profile and frequency of known risk factors or comorbidities for deep vein thrombosis in an urban district hospital in KwaZulu-Natal

Background

Although deep vein thrombosis (DVT) is a preventable disease, it increases the morbidity and mortality in hospitalised, patients, resulting in considerable economic health impact. The identification and primary prevention of risk factors using risk assessment and stratification with subsequent anti-thrombotic prophylaxis in moderate- to severe-risk categories is the most rational means of reducing morbidity and mortality.

Aim and setting

The aim of the study was to describe the profile and frequency of known risk factors or comorbidities of hospitalised medical patients with ultrasound-diagnosed DVT in an urban district hospital in KwaZulu-Natal.

Methods

A retrospective review of clinical notes of all medical patients (age ≥ 13 years) admitted to the hospital with ultrasound-diagnosed DVT between July and December 2013.

Results

The median age was 40 years (interquartile range 32–60 years) and female preponderance was 72.84%. HIV and tuberculosis emerged as the prevalent risk factors, accounting for 51.85% and 35.80%, respectively. Other risk factors observed were recent hospitalisation (34.57%), smoking (25.93%), previous DVT (19.75%) and congestive cardiac failure (18.52%).

Conclusion

DVT in our study occurred predominantly in young female patients unlike previous studies where patients were generally older. Furthermore, HIV and tuberculosis were the two most common known risk factors or comorbidities observed. Clinicians should have a heightened awareness of venous thromboembolism in patients with either condition or where both conditions occur together and appropriate thromboprophylaxis should be administered.

Study of Basic Coagulation Parameters among HIV Patients in Correlation to CD4 Counts and ART Status

INTRODUCTION

HIV infection is known to cause coagulation abnormalities by various mechanism, especially during its late course.

AIM

The objective of this study was to analyse platelet count, prothrombin time and activated partial thromboplastin time among HIV infected patients and to analyse these parameters with respect to their CD4 count and ART status.

MATERIALS AND METHODS

A case control study was conducted with 120 HIV infected patients and 40 normal individuals. The blood samples were collected after obtaining consent from the subjects. The blood samples were processed for platelet count, prothrombin time and activated partial thromboplastin time and CD4 count. The results were tabulated and analysed with statistical package.

RESULTS

The platelet count was significantly decreased in HIV infected patients compared to controls. Though HIV patients with CD4 count less than 200cells/mm(3) showed a decreased platelet count compared to those with CD4 count greater than 200cells/mm(3), it was not statistically significant. Prothrombin Time (PT) and Activated Partial Thromboplastin Time (aPTT) was significantly prolonged in HIV patients, but only aPTT showed significant inverse correlation with CD4 count. None of the parameters showed statistical significance on comparing HIV patients on ART with those not on ART.

CONCLUSION

Basic coagulation tests like platelet count, PT and especially aPTT can be used as prospective screening test to assess severity in HIV patients in resource limited settings where CD4 count is not available.

Using the pathogenic and nonpathogenic nonhuman primate model for studying non-AIDS comorbidities

With the advent of antiretroviral therapy that can control virus replication below the detection levels of conventional assays, a new clinical landscape of AIDS emerged, in which non-AIDS complications prevail over AIDS-defining conditions. These comorbidities are diverse and affect multiple organs, thus resulting in cardiovascular, kidney, neurocognitive and liver disease, osteopenia/osteoporosis, and cancers. A common feature of these conditions is that they are generally associated with accelerated aging. The mechanism behind these comorbidities is chronic excessive inflammation induced by HIV infection, which persists under antiretroviral therapy. Progressive simian immunodeficiency virus (SIV) infection of nonhuman primates (NHPs) closely reproduces these comorbidities and offers a simplified system in which most of the traditional human risk factors for comorbidities (i.e., smoking, hyperlipidemia) are absent. Additionally, experimental conditions can be properly controlled during a shorter course of disease for SIV infection. As such, NHPs can be employed to characterize new paradigms of AIDS pathogenesis and to test the efficacy of interventions aimed at alleviating non-AIDS-related comorbidities.

Biventricular thrombi in dilated cardiomyopathy in a patient with human immunodeficiency virus infection: a case report

BACKGROUND

Sub-Saharan Africa is undergoing epidemiological transition with an increase in the prevalence of cardiovascular diseases that will add to the already devastating burden of infectious diseases such as human immunodeficiency virus infection. Human immunodeficiency virus infection is increasingly being recognized as an important etiological factor for dilated cardiomyopathy with the potential complication of intraventricular thrombus. However, biventricular thrombi are extremely rare. We report on a rare finding of biventricular thrombi in dilated cardiomyopathy in a patient with human immunodeficiency virus infection in Cameroon.

CASE PRESENTATION

A 52-year old Cameroonian male patient with human immunodeficiency virus infection since 4 years, longstanding heavy alcohol consumption and cigarette smoking presented with gradually worsening shortness of breath, fatigue, persistent dry cough and lower extremity swelling of about two weeks duration. Congestive heart failure was diagnosed. Echocardiography showed left ventricular chamber enlargement with severe left ventricular systolic dysfunction and biventricular thrombi. The thrombi were immobile and regular in configuration, suggesting they were old. He was treated with a conventional heart failure treatment including loop diuretics and angiotensin converting enzyme inhibitors and anticoagulants for the biventricular thrombi. Six months later, a control echocardiography showed a significant decrease in the size of the thrombi. There was no evidence of systemic or pulmonary embolization during follow up.

CONCLUSION

Dilated cardiomyopathy may be seen in patients with human immunodeficiency virus infection, although other mechanisms needs to be assessed, but the occurrence of biventricular thrombi is rare.

The characteristics of HIV and AIDS patients with deep vein thrombosis at Dr. George Mukhari Academic Hospital

Background

Deep vein thrombosis (DVT) is 10 times more prevalent in HIV and AIDS patients than in the general population and is more common in patients with severe immune suppression (CD4 < 200 cells/mL). Opportunistic infections render HIV and AIDS patients susceptible to a hypercoaguable state, including lower protein S levels.

Aim and setting

To present the profile of HIV and AIDS patients who developed DVT in the primary care wards of Dr. George Mukhari Academic Hospital (DGMAH), Garankuwa.

Methods

Cross-sectional study of clinical records of admitted HIV and AIDS patients without DVT to the primary care wards, DGMAH, from 01 February 2010 to 31 January 2011.

Results

Two hundred and twenty-nine patients were admitted and 17 (7.4%) developed DVT. Of those that developed DVT, eight (47%) had infection with tuberculosis (TB), four (24%) had pneumonia and four (24%) had gastroenteritis. The risk of developing DVT was 8/94 (8.5%) in those with TB, 4/53 (7.5%) in those with gastroenteritis and 4/75 (5.3%) in those with pneumonia. The mean duration of stay was 14.1 days in those with DVT versus 4.0 days in those without.

Conclusion

HIV (and AIDS) is a hypercoaguable state and the risk of DVT is relatively high in patients with opportunistic infections. HIV and AIDS patients who are admitted to hospital with opportunistic infections may benefit from anti-thrombotic prophylaxis and further studies are needed to evaluate this.

An unusual cause of abdominal pain in an HIV-positive man

We report a case of an HIV-positive man on antiretroviral therapy (ART) who developed abdominal pain due to acute-on-chronic intestinal ischaemia secondary to superior mesenteric vein thrombosis (SMVT) requiring emergency surgery. He was found to have persistently low levels of protein C on thrombophilia screening. To the best of our knowledge, the association linking SMVT to protein C deficiency in an HIV-infected patient has never been reported in the literature.

Initial Presentation of HIV Infection With Two Successive Acute Arterial Thromboses: A Case Report

Introduction:

One of the complications of HIV infection is greater risk of thromboembolic events. A variety of mechanisms has been found to be responsible for prothrombotic tendency in patients with HIV infection.

Case Presentation:

A 27-year-old heterosexual smoker man was referred to our center due to a sudden-onset severe left lower extremity pain and claudication since three days prior to admission. In physical examination, end extremity coldness and discoloration as well as left lower extremity pulselessness were found. Color-Doppler sonography revealed a large thrombus in the left common iliac artery and two thrombi in the distal halves of both anterior and posterior tibialis arteries, so the patient was transferred to the operating room for proximal thrombectomy where the blood flow was reestablished and all pulses were then detectable. Two days later, the patient developed another similar episode from knee down and underwent the second thrombectomy. In evaluation, HIV Ab had positive result by ELISA.

Conclusions:

This case inspires consideration of HIV infection as a leading cause of thromboembolic event in individuals affected by the first episode of unprovoked one in whom diagnosis of HIV infection has not been established yet.

von Willebrand Factor is elevated in HIV patients with a history of thrombosis

Background: Arterial and venous thrombotic events are more prevalent in HIV infected individuals compared to the general population, even in the era of combination antiretroviral therapy. Although the mechanism is not fully understood, recent evidence suggests a role for chronic immune activation.

Methods: We reviewed the Dutch National HIV registry database for HIV infected patients in Rotterdam with a history of arterial or venous thrombosis and calculated the incidence. We collected samples from patients with and without thrombosis and compared plasma levels of lipopolysaccharide (LPS), LPS binding protein (LBP), soluble CD14 (sCD14), and von Willebrand Factor antigen level (vWF).

Results: During a 10-year period, a total of 60 documented events in 14,026 person years of observation (PYO) occurred, resulting in an incidence rate of 2.50, 2.21, and 4.28 for arterial, venous and combined thrombotic events per 1000 PYO, respectively. The vWF was elevated in the majority of study subjects (mean 2.36 SD ± 0.88 IU/ml); we found a significant difference when comparing venous cases to controls (mean 2.68 SD ± 0.82 IU/ml vs. 2.20 SD ± 0.77 IU/ml; p = 0.024). This difference remained significant for recurrent events (mean 2.78 SD ± 0.75; p = 0.043). sCD14 was positively correlated with LPS (r = 0.255; p = 0.003).

Conclusion: The incidence of venous thrombosis was two-fold higher in HIV infected patients compared to age-adjusted data from general population cohort studies. We couldn't find a clear association between immune activation markers to either arterial or venous thrombotic events. We observed a marked increase in vWF levels as well as a correlation of vWF to first and recurrent venous thrombo-embolic events. These findings suggest that HIV infection is an independent risk factor for coagulation abnormalities and could contribute to the observed high incidence in venous thrombosis. This could be a reason to prolong anti-thrombotic treatment in HIV patients with a history of thrombosis.

Risk of Venous Thromboembolism in Patients Infected with HIV: A Cohort Study

Introduction Human immunodeficiency virus (HIV) patients are at risk of developing thrombosis than general population. There are several intersecting mechanisms associated with HIV infection and antiviral therapy that are emerging, which may lead to vasculopathy and hypercoagulability in these patients. Methods We analyzed the HIV patients who followed up with our Vascular Medicine outpatient clinic with venous thromboembolism (VTE) over the past 3 years and followed them prospectively. The patients included were those who had minimum, regular follow-up of 3 months, with a Doppler scan in the beginning and last follow-up. Patients were analyzed for age, gender, race, site of thrombosis, coagulation factors, lipid panel, type of antiretroviral treatment, past or present history of infections or malignancy, CD4 absolute and helper cell counts at the beginning of thrombosis, response to treatment and outcome. Patients with HIV with arterial thrombosis were excluded. Results A total of eight patients were analyzed. The mean age was 49.87 years (range, 38-58 years). All were male patients with six patients having lower limb thrombosis, one patient with upper limb thrombosis related to peripheral inserted central catheter (PICC), and one patient had pulmonary embolism with no deep vein thrombosis. Most common venous thrombosis was popliteal vein thrombosis, followed by common femoral, superficial femoral and external iliac thrombosis. Two patients had deficiency of protein S, two had high homocysteine levels, one had deficiency of antithrombin 3, and one had increase in anticardiolipin Immunoglobulin antibody. All patients were taking nucleoside and nonnucleoside inhibitors but only two patients were taking protease inhibitors. There was history of lymphoma in one and nonsmall cell lung carcinoma in one patient. Three patients had past history of tuberculosis and one of these patients also had pneumocystis carinii pneumonia. The mean absolute CD4 counts were 383.25 cells/UL (range, 103-908 cells/UL) and helper CD4 counts were 22.5 cells/UL (range, 12-45 cells/UL). All were anticoagulated with warfarin or enoxaparin. There was complete resolution of deep vein thrombosis in two patients (one with PICC line thrombosis in 3 months and other with popliteal vein thrombosis in 1 year). There was extension of clot in one patient and no resolution in others. Seven patients are still alive and on regular follow-up. Conclusion Thrombosis in HIV patients is seen more commonly in middle aged, community ambulant male patients. Left lower limb involvement with involvement of popliteal vein is most common. Deficiency of protein S and hyperhomocystenaemia were noted in these patients. Most of these patients did not respond to therapeutic anticoagulation, but the extension of the thrombosis was prevented in majority of cases.

Systemic effects of inflammation on health during chronic HIV infection

Combination antiretroviral therapy for HIV infection improves immune function and eliminates the risk of AIDS-related complications but does not restore full health. HIV-infected adults have excess risk of cardiovascular, liver, kidney, bone, and neurologic diseases. Many markers of inflammation are elevated in HIV disease and strongly predictive of the risk of morbidity and mortality. A conceptual model has emerged to explain this syndrome of diseases where HIV-mediated destruction of gut mucosa leads to local and systemic inflammation. Translocated microbial products then pass through the liver, contributing to hepatic damage, impaired microbial clearance, and impaired protein synthesis. Chronic activation of monocytes and altered liver protein synthesis subsequently contribute to a hypercoagulable state. The combined effect of systemic inflammation and excess clotting on tissue function leads to end-organ disease. Multiple therapeutic interventions designed to reverse these pathways are now being tested in the clinic. It is likely that knowledge gained on how inflammation affects health in HIV disease could have implications for our understanding of other chronic inflammatory diseases and the biology of aging.

HIV-Associated Thromboembolic Phenomenon due to Protein C Deficiency

HIV-infected individuals are at a high risk of developing arterial and venous thromboembolism. Opportunistic infections, protease inhibitors, low CD4 count, antiphospholipid antibodies, protein S, and protein C deficiencies are some important risk factors associated with it. However, thromboembolic phenomenon due to protein C deficiency has been rarely reported. We report a case of a 12-year-old girl with facial palsy due to middle cerebral artery infarct because of HIV infection and associated protein C deficiency.

Association of hepatitis C with markers of hemostasis in HIV-infected and uninfected women in the women's interagency HIV study (WIHS)

BACKGROUND

Coinfection with HIV and hepatitis C virus (HCV) is common. HIV infection and treatment are associated with hypercoagulability; thrombosis in HCV is underinvestigated. Proposed markers of hemostasis in HIV include higher D-dimer, Factor VIII%, and plasminogen activator inhibitor-1 (PAI-1) antigen and lower total Protein S% (TPS) but have not been examined in HCV. We assessed the independent association of HCV with these 4 measures of hemostasis in a multicenter, prospective study of HIV: the Women's Interagency HIV Study.

METHODS

We randomly selected 450 HCV-infected (anti-HCV+ with detectable plasma HCV RNA) and 450 HCV-uninfected (anti-HCV-) women. HCV was the main exposure of interest in regression models.

RESULTS

Four hundred forty-three HCV+ and 425 HCV- women were included. HCV+ women had higher Factor VIII% (124.4% ± 3.9% vs. 101.8% ± 3.7%, P < 0.001) and lower TPS (75.7% ± 1.1% vs. 84.3% ± 1.1%, <0.001) than HCV- women, independent of HIV infection and viral load; there was little difference in PAI-1 or log10 D-dimer. After adjustment for confounders, these inferences remained. HIV infection was independently associated with higher Factor VIII% and log10 D-dimer and lower TPS.

CONCLUSIONS

HCV was independently associated with higher Factor VIII% and lower TPS consistent with hypercoagulability. Higher Factor VIII% and D-dimer and lower TPS were also strongly associated with HIV infection and levels of HIV viremia, independent of HCV infection. Further investigation is needed to determine if there is increased thrombotic risk from HCV. Studies examining hemostasis markers in HIV infection must also assess the contribution of HCV infection.