Unexplained thrombosis in HIV-infected patients receiving protease inhibitors: report of seven cases

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.

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.

Cardiovascular Disease and Thrombosis in HIV Infection

HIV infection has transitioned from an acute, fatal disease to a chronic one managed by antiretroviral therapy. Thus, the aging population of people living with HIV (PLWH) continues to expand. HIV infection results in a dysregulated immune system, wherein CD4+ T cells are depleted, particularly in the gastrointestinal tract, disrupting the gut epithelial barrier. Long-term HIV infection is associated with chronic inflammation through potentially direct mechanisms caused by viral replication or exposure to viral proteins and indirect mechanisms resulting from increased translocation of microbial products from the intestine or exposure to antiretroviral therapy. Chronic inflammation (as marked by IL [interleukin]-6 and CRP [C-reactive protein]) in PLWH promotes endothelial cell dysfunction and atherosclerosis. PLWH show significantly increased rates of cardiovascular disease, such as myocardial infarction (risk ratio, 1.79 [95% CI, 1.54-2.08]) and stroke (risk ratio, 2.56 [95% CI, 1.43-4.61]). In addition, PLWH have increased levels of the coagulation biomarker D-dimer and have a two to ten-fold increased risk of venous thromboembolism compared with the general population. Several small clinical trials analyzed the effect of different antithrombotic agents on platelet activation, coagulation, inflammation, and immune cell activation. Although some markers for coagulation were reduced, most agents failed to reduce inflammatory markers in PLWH. More studies are needed to understand the underlying mechanisms driving inflammation in PLWH to create better therapies for lowering chronic inflammation in PLWH. Such therapies can potentially reduce atherosclerosis, cardiovascular disease, and thrombosis rates in PLWH and thus overall mortality in this population.

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.

Analysis of the Coagulation Profile in Children with HIV Infection-Effect of Disease and Anti Retroviral Therapy

The pathogenesis of hypercoagulability in HIV infection is multifactorial and usually more than one factor is responsible for a thromboembolic episode. The present study was conducted to evaluate the effect of HIV infection and antiretroviral therapy on various coagulation parameters in paediatric patients. Forty two newly diagnosed paediatric patients with HIV infection who were enrolled at the Anti-Retro viral Therapy (ART) centre of Kalawati Saran Children's Hospital were included in the study. The patients were grouped into 4 clinical stages according to the WHO clinical staging of HIV disease. Coagulation tests [PT, aPTT, fibrinogen, D-Dimer and coagulation inhibitors i.e. Protein C (PC), Protein S (PS) and antithrombin III (AT III), Lupus anticoagulant (LA) and Anti phospholipid antibody (APLA)] were performed in all the patients at the time of diagnosis and repeated after 6 months. All the patients were started on antiretroviral therapy within 2 months of their diagnosis. At the time of diagnosis, prolonged PT and aPTT were observed in 30.9% and 23% of the cases respectively. Hyperfibinogenemia was seen in 11.9% of patients. D-Dimer was raised in 83.3% of patients. PS, PC & AT activities were reduced in 90.4%, 42.8% & 11.9% of cases respectively. A reduction in the PC and AT activity was seen from clinical stage 1 to 4, but the change was not statistically significant. On follow up after 6 months, a statistically significant reduction in the level of fibrinogen and D-Dimer was seen. Even though there was improvement in the activity of all the coagulation inhibitor after 6 months, statistically significant improvement was seen only for PS. The current study shows that HIV produces a hypercoagulable state in children. Raised d-dimer level and deficiency of natural anticoagulants contribute to the thrombophilic state.

Clinical Characteristics of HIV-Infected Patients with Venous Thromboembolism and Different CD4+ T Lymphocyte Levels

Objective

Methods

Results

Conclusion

Venous thromboembolic disease in adults admitted to hospital in a setting with a high burden of HIV and TB

BACKGROUND

HIV and tuberculosis (TB) independently cause an increased risk for venous thromboembolic disease (VTE): deep vein thrombosis (DVT) and/or pulmonary embolism (PE). Data from high HIV and TB burden settings describing VTE are scarce. The Wells' DVT and PE scores are widely used but their utility in these settings has not been reported on extensively.

OBJECTIVES

To evaluate new onset VTE, compare clinical characteristics by HIV status, and the presence or absence of TB disease in our setting. We also calculate the Wells' score for all patients.

METHODS

A prospective cohort of adult in-patients with radiologically confirmed VTE were recruited into the study between September 2015 and May 2016. Demographics, presence of TB, HIV status, duration of treatment, CD4 count, viral load, VTE risk factors, and parameters to calculate the Wells' score were collected.

RESULTS

We recruited 100 patients. Most of the patients were HIV-infected (n=59), 39 had TB disease and 32 were HIV/TB co-infected. Most of the patients had DVT only (n=83); 11 had PE, and 6 had both DVT and PE. More than a third of patients on antiretroviral treatment (ART) (43%; n=18/42) were on treatment for <6 months. Half of the patients (51%; n=20/39) were on TB treatment for <1 month. The median (interquartile range (IQR)) DVT and PE Wells' score in all sub-groups was 3.0 (1.0 - 4.0) and 3.0 (2.5 - 4.5), respectively.

CONCLUSION

HIV/TB co-infection appears to confer a risk for VTE, especially early after initiation of ART and/or TB treatment, and therefore requires careful monitoring for VTE and early initiation of thrombo-prophylaxis.

Thrombotic antiphospholipid syndrome in a child with human immunodeficiency virus: a rare case report

BACKGROUND

Antiphospholipid syndrome (APS) is a non-inflammatory autoimmune disorder induced by antiphospholipid antibodies, which occurs exceedingly rarely in pediatric population and even more rarely reported in HIV positive children. A case of 11 years old boy had a sudden onset of swelling in his left lower leg along with pain which were worsening gradually. Initially, topical ointment was applied for 1 month which were ineffective in reducing pain and swelling. Instead, the symptoms were aggravated and suddenly spread to the proximal thigh, accompanied by dyskinesia of left lower leg. Both color doppler ultrasonography and vascular CT scan of left lower leg revealed deep venous thrombosis. His serum anti-phospholipid antibodies (aPLs) were tested positive. He was a known case of HIV virological failure with substantial HIV viral load (VL) despite receiving regular antiretroviral therapy (ART). His symptoms improved after giving aggressive antithrombotic and high dose corticosteroid treatments.

CONCLUSION

When pediatric patients develop thrombotic disease, APS also needs to be ruled out. The autoantibodies levels should be routinely tested to look for recurrent thrombosis in children with HIV/AIDS.

Venous thromboembolism in people living with HIV infection (PWH)

The risk of venous thromboembolism (VTE) and of recurrent VTE remain elevated in people living with HIV compared to controls still with contemporary antiretroviral therapy (ART). The pathophysiology of VTE in HIV is multi factorial and includes an interplay among traditional risk factors, HIV-specific factors, behavioral factors, exposure to ART and other therapies, coinfections, and co-morbidities.

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.

Venous Thrombosis Among Patients with AIDS

Thrombosis has been considered an uncommon complication in patients with AIDS. In a 42-month period, 28 adult male homosexuals with AIDS experienced 34 thrombotic events. All but three received HAART regimen, two a successful round of double nucleoside analog therapy, and one patient received no treatment. Median age of group was 38.5 years (range, 24 to 56 years). Median time from HIV infection to thrombosis was 40.5 months (range, 3 to 108 months). No patient had previous thrombosis, family history of thrombosis, or prothrombotic conditions. There were 31 deep vein thromboses, two pulmonary thromboembolisms, and one renal vein thrombosis. Six patients had two thrombotic events. The rate of thrombosis during the 42-month study period was 1.52% (cumulative incidence = 0.30%/year), while the rate of thrombosis in 600 patients before the era of protease inhibitor therapy was 0.33% (cumulative incidence approximately 0.055%/year) (p < 0.001). Due to high incidence of thrombotic recurrences and hemorrhagic complications while using oral anticoagulants, acetylsalicylic acid was initiated; no thrombotic episodes were recorded while using this drug. Protein C and protein S deficiency were found in nine and two patients, respectively. Two patients had lupus anticoagulant and two activated protein C resistance (APCR) without FV Leiden mutation (APCR test was negative after initial screening). Fifteen patients had no thrombophilic abnormalities. These data suggest that protease inhibitors could be a risk factor for venous thrombosis not due to thrombophilic abnormalities but likely related to abnormalities in platelets or endothelium.

Atherosclerotic Cardiovascular Disease Risk in the HAART-Treated HIV-1 Population

Atherosclerotic cardiovascular disease (CVD), a leading cause of morbidity and mortality in the general population, is also an increasing cause for concern for HIV-infected patients. A number of risk factors for CVD are also associated with HIV disease and HIV therapy, particularly insulin resistance, metabolic dyslipidemia, and inflammation. For example, atherogenic dyslipidemia, a side effect of HIV therapy, is an established risk for CVD in the non-HIV-infected population. As our understanding of atherosclerotic disease evolves, new markers of CVD risk have been identified, including metabolic syndrome definitions and C-reactive protein, a marker of inflammation. Use of these markers, in association with established risk factor guidelines, may serve as important tools in helping HIV physicians implement drug regimens that allow optimum management of metabolic complications associated with HIV and HAART, and thereby reduce CVD risk. The objective of this article is to review the mechanisms of atherosclerotic CVD and to discuss risk factors and markers that can be applied in the evaluation and treatment of CVD in the HIV-positive population.

Venous thromboembolism among HIV-positive patients and anticoagulation clinic outcomes integrated within the HIV primary care setting

The purpose of this study was to explore factors associated with venous thromboembolism (VTE) among a cohort of HIV-infected patients and to describe early outcomes of warfarin anticoagulation therapy treated in a pharmacist-based anticoagulation clinic (ACC). A nested case-control study was conducted using the University of Alabama at Birmingham 1917 HIV Clinic Cohort. Conditional logistic regression was used to estimate factors associated with VTE. Among HIV-infected VTE cases, ACC-managed patients were compared to primary care provider (PCP)-managed patients to determine Time within Therapeutic INR Range (TTR). CD4 < 200 cells/µl (OR = 4.50; 95% CI = 1.52, 13.37; p = 0.007) and prior surgical procedures (13.20; 1.56; 111.4; p = 0.018) demonstrated positive associations with VTE, whereas longer HIV duration demonstrated a negative association (0.87; 0.78, 0.98; p = 0.019). TTR was 56.2% among ACC-managed patients compared to 30.5% of PCP-managed patients (p = 0.174). Overall, prior surgical procedures and low CD4 count were associated with an increased risk of VTE among HIV-infected patients. Despite small sample size, patients managed in ACC tend to achieve greater proportion of TTR compared to those managed by PCPs, suggesting that this model of therapy may provide additional benefits to HIV-infected patients.

Human immunodeficiency virus-associated lung malignancies

This review of lung malignancies in human immunodeficiency virus (HIV) briefly highlights key epidemiologic and clinical features in the pulmonary involvement of AIDS-defining malignancies of Kaposi sarcoma and non-Hodgkin lymphoma. Then, focusing on non-AIDS defining lung cancer, the epidemiology and mechanisms, clinical presentation, pathology, treatment and outcomes, and prevention of HIV-associated lung cancer are discussed. Finally, the important knowledge gaps and future directions for research related to HIV-associated lung malignancies are highlighted.

[Venous thrombosis and bilateral arterial occlusion of lower limb revealing HIV infection]

Human immunodeficiency virus (HIV) infection can cause vascular complications. This is most often of lower limb venous thrombosis. Rare cases of limb ischemia indicative of HIV infection have been described.We report a case of venous thrombosis of the left lower limb and bilateral lower arterial ischemia revealing an HIV infection in a patient of 44 years. The CD4 count was 195/mm(3). Investigations on coagulation were not realized. The patient was amputated both his legs.

Impact of short-term antiretroviral therapy (START) on some fibrinolytic markers in HIV-infected Nigerian adults: preliminary findings from the START study

BACKGROUND

Derangement in fibrinolytic markers can result in thrombosis and cardiovascular problems. Antiretroviral therapy (ART) has been reported to affect the levels of these markers. It is unclear how long a patient can be exposed to ART before the effect of the drugs on the fibrinolytic markers becomes noticeable; this short-term antiretroviral therapy (START) study aimed to answer this question.

METHODS

Twenty human immunodeficiency virus (HIV)-positive subjects on ART and 20 controls (non-ART) were progressively monitored for three months. CD4 T-cell count was determined while D-dimer, t-PA, and PAI-1 parameters were determined.

RESULTS

CD4 T-cell count increased from 192 μL/mL at baseline to 323 μL/mL at month 3 among patients on ART. D-dimer concentrations decreased from 301.0 μL/mL at baseline to 172.0 μL/mL at month 2, then increased to 226.0 μL/mL at the end of the third month. The median baseline concentration of PAI-1 at the beginning of therapy was 14.0 μg/mL, which increased progressively to 18.2 μg/mL at the end of the third month. The baseline concentration of t-PA at the beginning of therapy was 5.15 μg/mL. This progressively declined to 1.10 μg/mL at the end of the first month and reached 1.45 μg/mL and 1.5 μg/mL at the end of the second and third months, respectively. D-dimer was positively and significantly correlated with CD4 cell counts in both AIDs-associated retrovirus (ARV) and non-ARV patients (r = -0.304, P < 0.01 vs r = -0.477, P < 0.001). t-PA was negatively correlated with CD4 T-lymphocytes in those undergoing ART (r = -0.294, P < 0.01).

CONCLUSION

A progressive increase in PAI-1 and steady decline in t-PA concentrations within 3 months of commencement of ART could predispose patients to thrombotic disorders earlier than is expected. Pre-thrombotic assessment during therapy is therefore advocated.

HIV-Associated Venous Thromboembolism

HIV infection has been recognized as a prothrombotic condition and this association has now been proven by a large number of studies with a reported VTE frequency among HIV-infected patients ranging from 0.19% to 7,63 %/year. HIV infection is associated with a two to tenfold increased risk of venous thrombosis in comparison with a general population of the same age. Some risk factors demonstrated a strongest association with VTE such as, low CD4⁺ cell count especially in the presence of clinical AIDS, protein S deficiency, and protein C deficiency. Whereas other risk factors are still controversial like protease inhibitor therapy, presence of active opportunistic infections and presence of antiphospholipid antibodies, including anticardiolipin antibodies and lupus anticoagulant. Physicians caring for HIV positive patients should be able to recognize and treat not only the well-known opportunistic infections and malignancies associated with this chronic disease, but also be alert to the less well-known complications such as thromboses. Pulmonary embolism should be included in the differential diagnosis when patients with HIV/AIDS have unexplained dyspnea or hypoxemia. In younger individuals with VTE, especially men, without other identifiable risk factors for VTE, HIV should be considered. Because interactions between warfarin and antiretrovirals is possible, health care providers should also be alert to the potential of dangerously high or low INRs when they are giving anticoagulants to patients with HIV infection who are undergoing antiretroviral therapy.

The thrombotic profile of treatment-naive HIV-positive Black South Africans with acute coronary syndromes

BACKGROUND

Patients with human immunodeficiency virus (HIV) infection on protease inhibitors (PIs) have a heightened risk of arterial thrombosis but little is known about treatment-naive patients.

METHODS/RESULTS

Prospective study from South Africa comparing thrombotic profiles of HIV-positive and -negative patients with acute coronary syndrome (ACS). A total of 30 treatment-naive HIV-positive patients with ACS were compared to 30 HIV-negative patients with ACS. Patients with HIV were younger; and besides smoking (73% vs 33%) and low high-density lipoprotein (HDL; 0.8 ± 0.3 vs 1.1 ± 0.4), they had fewer risk factors. Thrombophilia was more common in HIV-positive patients with lower protein C (PC; 82 ± 22 vs 108 ± 20) and higher factor VIII levels (201 ± 87 vs 136 ± 45). Patients with HIV had higher frequencies of anticardiolipin (aCL; 47% vs 10%) and antiprothrombin antibodies (87% vs 21%).

CONCLUSION

Treatment-naive HIV-positive patients with ACS are younger, with fewer traditional risk factors but a greater degree of thrombophilia compared with HIV-negative patients.

Venous thromboembolic disease in the HIV-infected patient

OBJECTIVE

Infection with the HIV has developed into a chronic illness, with longer-term complications increasingly being seen. There is increasing evidence that infection with HIV may be associated with a hypercoagulable state. This study examines the association of HIV infection with the incidence of both pulmonary embolism and deep venous thrombosis.

METHODS

This study was a weighted analysis of data from National Hospital Discharge Survey, a national annual probability survey of discharges from short-stay non-Federal hospitals, from 1996-2004. The risk of pulmonary embolism and/or deep venous thrombosis in an HIV+ individual was ascertained for each age group by calculation of an odds ratio (OR) with a 95% confidence interval (CI). A common OR was computed across strata to evaluate the overall association between PE/DVT and HIV while adjusting for effects of age.

RESULTS

The overall age-adjusted OR indicates a statistically significant increase of 43% for PE in HIV+ individuals as opposed to HIV- individuals (OR, 1.43; 95% CI, 1.39-1.46). This increase differs by age group, with age group 21 to 50 years having the highest odds for PE among HIV+ individuals (OR, 1.58; 95% CI, 1.54-1.63).

CONCLUSIONS

The data supports the hypothesis that HIV-infected individuals are more likely to have clinically detected thromboembolic disease as opposed to non-HIV-infected individuals. This study reveals up to a 43% increase in OR of developing a PE, 10% increase in developing a DVT, and 40% increase in developing PE or DVT in an HIV-infected individual over the 9-year study period after adjusting for age.

Mixed Arterial and Venous Thromboembolism in a Person with HIV Infection

People with human immunodeficiency virus (HIV) infection are more susceptible to thromboembolic events. Venous thromboembolism (VTE) occurs frequently in HIV infected persons but arterial thrombosis has only rarely been reported. We describe a case of a person with HIV infection who developed an arterial thrombosis and 3 months later an extensive VTE. Several non-HIV and HIV related thrombogenic factors were identified.

Human immunodeficiency disease: how should it affect surgical decision making?

BACKGROUND

The ever-increasing prevalence of human immunodeficiency virus (HIV) infection and the continued improvement in clinical management has increased the likelihood of surgery being performed on patients with this infection. The aim of the review was to assess current literature on the influence of HIV status on surgical decision-making.

METHODS

A literature review was performed using MEDLINE articles addressing "human immunodeficiency virus," "HIV," "acquired immunodeficiency syndrome," "AIDS," "HIV and surgery." We also manually searched relevant surgical journals and completed the bibliographic compilation by collecting cross references from published papers.

RESULTS

Results of surgery between noninfected and HIV-infected individuals and between HIV-infected and acquired immunodeficiency syndrome (AIDS) patients are variable in terms of morbidity, mortality, and hospital stay. The risk of major surgery is not unlike that for other immunocompromised or malnourished patients. The multiple co-morbidities associated with HIV infection and the availability of highly active antiretroviral therapy must be considered when assessing and optimizing the patient for surgery. The clinical stage of the patient's disease should be evaluated with a focus on the overall organ system function. For patients with advanced HIV disease, palliative surgery offers relief of acute problems with improvement in the quality of life. When indicated, diagnostic surgery assists with further decision-making in the medical management of these patients and hence should not be withheld.

CONCLUSION

HIV infection should not be considered a significant independent factor for major surgical procedures. Appropriate surgery should be offered as in normal surgical patients without fear of an unfavorable outcome.

Review: thromboses among HIV-infected patients during the highly active antiretroviral therapy era

Venous thrombotic events (VTEs) may occur at higher rates among patients with HIV; some studies suggest that highly active antiretroviral therapy (HAART) may increase the risk for these potentially life-threatening events. We performed a retrospective study among patients with HIV to evaluate the incidence and risk factors for VTEs during the HAART era. A literature review was performed examining VTEs in the pre- and post-HAART eras. Seventeen (3.7%) of 465 patients with HIV experienced a VTE. The overall incidence rate of deep VTEs among HIV-positive persons was 377 cases per 100,000 person-years, a fourfold higher rate compared to age-matched males in the general population. The median age at VTE was 36 years (range, 27-68). Patients with a thrombosis compared to those without had significantly lower current CD4 (153 versus 520 cells/mm(3), p < 0.001) and nadir (76 versus 276 cells/mm(3), p < 0.001) CD4 counts, higher viral loads (3.6 versus 1.7 log(10) copies per milliliter, p = 0.003), and more likely to have a diagnosis of AIDS (76% versus 32%, p < 0.001); there were no differences in demographics, hyperlipidemia, current use of HAART, the duration of HAART or protease inhibitor (PI) exposure. A review of the literature noted 129 VTE cases; mean age was 40 years, mean CD4 count was 181 cells/mm(3), the majority of patients were not receiving HAART, and the most common risk factor was an ongoing infection. Thrombotic events are occurring among patients with HIV despite their relatively young ages. Advanced HIV disease is a risk factor for development of thromboses, possibly due to an increased inflammatory state or the presence of concurrent comorbidities such as infections. HAART or PI therapy does not appear to play a significant role in the occurrence of VTEs.

Venous thromboembolism in patients with HIV/AIDS: a case-control study

BACKGROUND

Retrospective cohort studies of HIV-infected patients suggest an incidence of venous thromboembolism (VTE) of 1% to 2%, which is 10 times that expected among people without HIV. We investigated the prevalence of established risk factors for VTE in this population and explored novel risk factors.

METHODS

We conducted a case-control study using patients in the Johns Hopkins University AIDS Service cohort. We used conditional logistic regression and paired t tests to test for covariates significantly associated with VTE.

RESULTS

We identified 160 patients with VTE diagnosed radiologically or with a clinical course consistent with VTE; 23% of the cases of VTE were diagnosed in hospitalized patients. The incidence of VTE was approximately 0.5% per patient-year. Patients with VTE and control patients did not differ by gender, but black patients were overrepresented among those with VTE (odds ratio [OR]=1.9, 95% confidence interval [CI]: 1.11 to 3.08) and patients with VTE were older than controls (mean: 39 vs. 37 years; P=0.001). Patients with VTE had lower CD4 counts (229 vs. 362 cells/mm; P<0.0001), higher HIV RNA titers (120,254 vs. 71,262 copies/mL; P=0.013), and lower hemoglobin concentrations (11.4 vs. 12.7 g/dL; P<0.0001) preceding the event than those without VTE. The use of highly active antiretroviral therapy was not associated with VTE. In multivariate analyses, independent risks for VTE were age, hospitalization in the past 3 months (OR=13, 95% CI: 6.4 to 27), central venous catheter use in the past 3 months (OR=6.0, 95% CI: 2.3 to 16), and a CD4 count<500 cells/mm (OR=3.0, 95% CI: 1.2 to 7.8).

CONCLUSIONS

The incidence of VTE in our cohort is similar to that reported in other cohorts of patients with HIV. Recent hospitalization was the risk factor most strongly associated with VTE.

[Thromboembolic events at the time of highly active antiretroviral therapies against human immunodeficiency virus]

PURPOSE

Vein thrombosis risk and pulmonary embolism seem to be more important among human immunodeficiency virus (HIV) infected patients.

METHOD

We performed a retrospective study including 780 HIV positive patients followed-up between January 2000 and June 2005 at the University Hospital of Clermont-Ferrand.

RESULTS

Among the 780 HIV-infected patients, six cases of thromboembolic events were identified including, four with pulmonary embolism. All the patients were receiving lopinavir/ritonavir combination.

CONCLUSION

Although uncommon, pulmonary embolism occurs more frequently among HIV positive patients than in general population. Clinicians must remain aware about the possibility of the occurrence of a thromboembolic event especially during the first few months after introduction of the antiretroviral therapy.

Current Update on HIV-associated Vascular Disease and Endothelial Dysfunction

Highly active antiretroviral therapy (HAART) has greatly reduced the risk of early death from opportunistic infections and extended the lifespan of people infected with the human immunodeficiency virus (HIV). Thus, many complications and organic damage in the HIV-infected population emerge. Cardiovascular disease as coronary artery disease has become a matter of particular concern. Its incidence is greatly increased in the HIV-infected population over that of people of the same age in the absence of general cardiovascular risk factors. Despite several clinical and laboratory studies in the association between HIV infection and cardiovascular disease, the pathogenic mechanisms of this significant clinical problem are largely unknown and are now under active investigation. Endothelial dysfunction is possibly the most plausible link between HIV infection and atherosclerosis. Increased expression of adhesion molecules such as intercellular adhesion molecule (ICAM)-1 and endothelial adhesion molecule (E-selectin) and inflammatory cytokines such as tumor necrosis factor (TNF)-alpha and interleukin (IL-6 has been reported in HIV-positive patients. The effect of HAART on endothelial function in HIV-positive patients is also demonstrated. In this review, we focus on the recent research update of HIV-associated vascular disease and vascular injury. We analyze and discuss the recent clinical and laboratory investigations on the effect of HIV, viral protein, and HAART therapy on endothelial injury and vascular disease; identify the areas of controversy and clinical relevance; and suggest some directions for future research.

Progressive Prothrombotic State in Women With Advancing HIV Disease

BACKGROUND

HIV-infected patients are at increased risk for venous thrombotic events (VTEs). We sought to determine if advancing stages of HIV were associated with coagulation abnormalities that could predispose to VTE.

METHODS

Functional protein S, factor VIII activity, and lupus anticoagulant were assayed in 144 participants of the Women's Interagency HIV Study. Women with conditions associated with VTE (cancer, pregnancy, hormone use, acute infection, cancer, and autoimmune disease) were excluded. Subjects included 34 women with history of clinical AIDS, 11 with immunologic AIDS (CD4 count, <200 cells/dL), 49 with asymptomatic HIV, and 50 HIV-negative comparators.

RESULTS

We found progressive decreases in protein S, when comparing HIV-negative women (median, 76%) to women with asymptomatic HIV (median, 67%), immunologic AIDS (median, 62%), or clinical AIDS (median, 46%; P < 0.0001). Similarly, advancing HIV was associated with stepwise increases in factor VIII, from a median of 116% in HIV-negative women to 149% in those with asymptomatic HIV, 196% in those with immunologic AIDS, and 211% in those with clinical AIDS (P < 0.0001). No subject had lupus anticoagulant.

CONCLUSIONS

Advancing HIV is associated with progressive abnormalities of protein S and factor VIII; both of which are associated with increased risk for VTE, thus providing a biologic mechanism for the increased prevalence of VTE in HIV.

Portal vein thrombosis in a patient with HIV treated with a protease inhibitor-containing regimen

We report a case of an HIV seropositive female patient treated with a protease inhibitor-containing regimen who developed recurrent severe life-threathening episodes of haematemesis over time, caused by ruptured oesophageal varices as a consequence of a portal vein thrombosis. Coagulation tests revealed a protein S deficiency, an elevated homocysteinemia and a constitutional elevated plasma factor VIII coagulant activity. These coagulopathies and the HIV infection are independent risk factors for developing venous thromboembolic events. The protease inhibitor treatment may have played a role in increasing the thromboembolic risk. The recurrent bleedings only stopped after invasive surgery. The invasive splenorenal shunt operation was in this case a life-saving procedure.

Thrombectomy in HIV related peripheral arterial thrombosis: a preliminary report

OBJECTIVES

To evaluate the limb salvage rate in patients undergoing thrombectomy for HIV related peripheral arterial thrombosis.

METHODS

A prospective review of patients with HIV related peripheral arterial thrombosis managed at the Durban Metropolitan Vascular Service in Kwazulu-Natal South Africa over a 5-year (1998-2003) period. All patients underwent thrombectomy.

RESULTS

Twenty-two patients (20 males) with HIV related peripheral arterial thrombosis (two upper limbs, 20 lower limbs) were included in the study. The median age was 36 years (24-46 years). All patients had rest pain and seven patients had gangrene (digital five, forefoot two). Seven patients had a short history of claudication before development of rest pain. Mean duration of symptoms was 30 days (1-120 days) with 10 patients presenting within 24 h. Most patients had a good general state of health and only three had clinical evidence of HIV infection. Ten patients who presented with threatened limbs from acute arterial occlusion were subjected to thrombectomy without any diagnostic investigations. Twelve patients who did not present with critical limb ischaemia had duplex ultrasonography, which showed arterial occlusion by a thrombus with normal proximal arteries. The striking features were the normal proximal vessels and absence of distal run-off. The search for an underlying cause, echocardiography in seven patients and coagulation screening in 10 patients, was always negative. All patients were subjected to thrombectomy with an on-table angiogram and received systemic heparin intra-operatively and deltaparin post-operatively. In 20 patients, duplex ultrasonography confirmed re-thrombosis within 48 h. Two patients remained with patent arteries. Most (16/20) patients who re-thrombosed required a major amputation and thrombectomy did not alter the level of amputation. The other four patients with re-thrombosis had symptomatic relief. Three patients died within 30 days of thrombectomy, all of HIV related complications. Overall the limb salvage rate was 6/22 (27%).

CONCLUSION

Limb salvage rate following thrombectomy in HIV related peripheral arterial thrombosis is very low. Duplex ultrasonography appears to be an adequate radiological diagnostic investigation for these patients.

Carotid artery aneurysm in human immunodeficiency virus infection

The case is reported of a patient with human immunodeficiency virus (HIV) infection presenting with isolated headache as the presumed manifestation of a cavernous carotid aneurysm. The relationship between HIV and aneurysms is discussed. Clinicians should be aware of the possibility of carotid aneurysms in HIV-positive patients, even in areas where HIV is not endemic and when no neurological deficit is present. Magnetic resonance imaging is recommended as the initial diagnostic study.

Thrombosis and a hypercoagulable state in HIV-infected patients

Human immunodeficiency virus infection is an illness with protean manifestations including hematological abnormalities. Thromboembolic complications in HIV-infected patients have been described. Recent literature describes an incidence ranging from 0.26% to 7.6%; higher incidence is seen in patients with active opportunistic infections or malignancy, and in patients with the acquired immunodeficiency syndrome. A variety of potential mechanisms have been proposed to account for the observed hypercoagulability in HIV-infected patients. These include the presence of antiphospholipid-anticardiolipin antibodies, decreased activities of natural anticoagulants (especially protein S), and increased platelet activation. Recent epidemiological studies emphasize the increased incidence of thromboembolic events including myocardial infarction in the HIV-infected population after the introduction of highly active antiretroviral therapy. The use of protease inhibitors in particular is implicated. A hypercoagulable state and especially thromboses are emerging as clinical issues in HIV-infected patients. Further studies are in order to more clearly delineate the pathophysiologic mechanism(s) of thromboses in HIV-infected patients.

Thrombotic complications in patients infected with HIV in the era of highly active antiretroviral therapy: a case series

BACKGROUND

Recent reports suggest that patients infected with human immunodeficiency virus (HIV) may have an increased risk of developing thrombosis, but the etiology, risk factors, and clinical course remain largely undefined, with few descriptive case series.

METHODS

We identified 30 patients from an HIV outpatient clinic (treatment population, 650 persons) who had had a total of 43 venous or arterial thromboses during 1996-2002. Data pertaining to demographic characteristics, medical history, thrombosis presentation, and clinical outcomes were abstracted from patient medical records.

RESULTS

The median patient age at the time of thrombosis was 43 years. Although the presence of persistent antibody to phospholipids was the most common abnormal finding in the laboratory, evaluation of thrombophilia, cases of low levels of proteins C and S and antithrombin III, and elevated levels of factor VIII and homocysteine were also identified. Seventy-seven percent of the patients smoked cigarettes, 57% had dyslipidemia, and 43% had a malignancy (most commonly Kaposi sarcoma). Although the Centers for Disease Control and Prevention (CDC) classification for 16 patients (53%) was C3, most showed evidence of immune reconstitution (median CD4 cell count, 290 cells/ mu L) and control of the virus (median HIV load, 2290 copies/mL). Lower extremity, deep vein thrombosis and pulmonary emboli accounted for 66% of all thrombotic events. The median time to diagnosis of thrombosis was 1 day (range, 3 h to 3 weeks).

CONCLUSIONS

Patients in this series were characterized by a relatively young age at the time of thrombosis, a predominance of elevated levels of lipids, a history of malignancy, and an advanced CDC HIV classification but not by a low CD4 cell count or an elevated HIV load.

Antiphospholipid Antibody Syndrome Manifesting as a Deep Venous Thrombosis and Pulmonary Embolism in a Patient with HIV

Although antiphospholipid antibodies are commonly detected in patients with HIV disease, the clinical manifestations of antiphospholipid syndrome are uncommon. The authors describe a woman with HIV and elevated antiphospholipid antibody levels who presented with deep venous thrombosis and pulmonary embolism. This case contradicts the general belief that these antibodies are not clinically significant in patients with HIV.

Frequency of and outcome of acute coronary syndromes in patients with human immunodeficiency virus infection

Fifty-one patients with human immunodeficiency virus infection and acute coronary syndromes were identified. Nearly all patients (98%) had traditional coronary risk factors. Revascularization procedures were performed safely with low in-hospital mortality.

AIDS and thrombosis: retrospective study of 131 HIV-infected patients

The recent literature contains reports of thrombotic episodes occurring in patients with human immunodeficiency virus (HIV) infection and various abnormalities predisposing to a hypercoagulable state have also been reported in such patients. To study the incidence of thrombosis in patients infected with HIV, and to assess the correlation of thrombosis with the degree of immunosuppression as well as the association with active illnesses and neoplasms, we reviewed the charts of 131 patients, which include all the patients with the diagnosis of HIV admitted or seen in the clinic between January 1, 1993, and January 1, 1998. The diagnosis of thrombosis was based on documented reports of venous plethysmography or venography for deep venous thrombosis and ventilation-perfusion scan or pulmonary angiography for pulmonary embolus. Risk factors for thrombotic disease were evaluated including general risk factors such as family history, ambulatory status, medications, and data were also collected regarding CD4 cell counts and the presence of concurrent or remote opportunistic infections, acquired immune deficiency syndrome (AIDS)-related malignancy or other AIDS-related diseases at the time of diagnosis of the thrombotic event. We also reviewed the medical literature via MEDLINE and found 45 cases of patients with HIV who developed thromboembolic complications. We found thrombotic complications in 9 of 37 patients with a CD4 count less than 200 cells/mm3 and in 1 of the remaining 94 patients with a CD4 count more than 200 cells/mm3. The difference was significant, with p = 0.00004, and the estimated odds of an event given CD4 cell counts less than 200/mm3 is 29.89 (95% confidence interval). Three patients had abnormalities of anticoagulation proteins. There was a history of opportunistic infections in 5 patients and malignancy in 3 patients. Two patients with autoimmune hemolytic anemia (AIHA) secondary to HIV-infection developed PE upon transfusion of packed red blood cells. The results of this study suggests that AIDS appears to predispose to thrombosis. It also revealed a significant correlation between thrombotic disease and CD4 counts (<200/mm3) as well as the presence of opportunistic infections, AIDS-related neoplasms, or autoimmune disorders associated with HIV such as AIHA. Therefore, clinicians caring for these patients should be aware of thromboembolic disease as a possible complication of AIDS. Further studies to elucidate the mechanisms underlying this abnormal hemostatic profile, the epidemiology, and to answer several questions such as should patients with risk factors for HIV infection who develop thromboembolic complications be further evaluated including tests for HIV are warranted.

HIV and thrombosis: a review

The array of clinicopathologic factors associated with acquired immune deficiency syndrome (AIDS) patients continues to increase and surprise many physicians. The recent literature contains reports of thrombotic episodes occurring in patients with human immunodeficiency virus (HIV) infection. Various abnormalities predisposing to a hypercoagulable state have also been reported in AIDS patients including the presence of antiphospholipid antibodies and the lupus anticoagulant; deficiencies of protein C, protein S, heparin cofactor II, and antithrombin and increased levels of von Willebrand factor, and d-dimers. These abnormalities correlate with the severity of HIV-associated immunosuppression as measured by the CD4 cell counts and with the presence of concurrent infectious or neoplastic diseases. The authors reviewed the medical literature and describe various abnormalities predisposing to a hypercoagulable state in AIDS patients along with the management of such complications. This issue is important because deep venous thrombosis (DVT), pulmonary embolus (PE), or thrombosis at other sites can develop in patients with AIDS who are ambulatory and have no known risk factors for pathologic thrombus formation, providing another challenge in an already difficult clinical situation. This also provides a strong rationale for careful prospective studies focusing on the prevalence and risk factors involved in the development of thromboembolic complications in patients with AIDS.