Cytomegalovirus retinitis in patients with AIDS in Europe. AIDS in Europe Study Group

The role of polymorphonuclear neutrophils during HIV-1 infection

It is well-recognized that human immunodeficiency virus type-1 (HIV-1) mainly targets CD4⁺ T cells and macrophages. Nonetheless, during the past three decades, a huge number of studies have reported that HIV-1 can directly or indirectly target other cellular components of the immune system including CD8⁺ T cells, B cells, dendritic cells, natural killer cells, and polymorphonuclear neutrophils (PMNs), among others. PMNs are the most abundant leukocytes in the human circulation, and are known to play principal roles in the elimination of invading pathogens, regulating different immune responses, healing of injured tissues, and maintaining mucosal homeostasis. Until recently, little was known about the impact of HIV-1 infection on PMNs as well as the impact of PMNs on HIV-1 disease progression. This is because early studies focused on neutropenia and recurrent microbial infections, particularly, during advanced disease. However, recent studies have extended the investigation area to cover new aspects of the interactions between HIV-1 and PMNs. This review aims to summarize these advances and address the impact of HIV-1 infection on PMNs as well as the impact of PMNs on HIV-1 disease progression to better understand the pathophysiology of HIV-1 infection.

Neutropenia during HIV infection: adverse consequences and remedies

Neutropenia frequently occurs in patients with Human immunodeficiency virus (HIV) infection. Causes for neutropenia during HIV infection are multifactoral, including the viral toxicity to hematopoietic tissue, the use of myelotoxic agents for treatment, complication with secondary infections and malignancies, as well as the patient's association with confounding factors which impair myelopoiesis. An increased prevalence and severity of neutropenia is commonly seen in advanced stages of HIV disease. Decline of neutrophil phagocytic defense in combination with the failure of adaptive immunity renders the host highly susceptible to developing fatal secondary infections. Neutropenia and myelosuppression also restrict the use of many antimicrobial agents for treatment of infections caused by HIV and opportunistic pathogens. In recent years, HIV infection has increasingly become a chronic disease because of progress in antiretroviral therapy (ART). Prevention and treatment of severe neutropenia becomes critical for improving the survival of HIV-infected patients.

Incidence of cytomegalovirus (CMV) retinitis in second eyes of patients with the acquired immune deficiency syndrome and unilateral CMV retinitis

PURPOSE

To evaluate the risk and risk factors for developing cytomegalovirus (CMV) retinitis in previously uninvolved second eyes among patients with unilateral CMV retinitis.

DESIGN

Cohort study.

METHODS

SETTINGS

Single-center academic AIDS ophthalmology practice.

PATIENT POPULATION

Three hundred seventy-six consecutive patients with AIDS and unilateral CMV retinitis were followed from the time of CMV retinitis diagnosis for the development of second-eye retinitis.

EXPERIMENTAL PROCEDURES

Demographic and clinical characteristics were noted at baseline. Use of highly active antiretroviral therapy (HAART) and immune recovery in response to HAART were noted prospectively.

MAIN OUTCOME MEASURE

Development of CMV retinitis in a previously uninvolved eye.

RESULTS

Ninety-one percent of subjects received systemic anti-CMV treatment. Second-eye retinitis occurred in 26.1%/person-year (19.6% within the first 6 months), less than half the rate previously reported in untreated groups. Initial CD4+ T cell count >12 cells/microl, use of HAART, and initial posterior pole involvement were associated with 64%, 46%, and 41% reductions in incidence vis-à-vis comparison groups. Benefit from HAART was limited to that subset who developed immune recovery of a degree expected to restore innate control of CMV (a rise in the CD4+ T cell count by >50 cells/microl to a level >100 cells/microl).

CONCLUSIONS

The risk of second-eye retinitis is substantial in patients with unilateral CMV retinitis but appears to be reduced by anti-CMV therapy and by HAART-induced immune recovery. Patients are at highest risk when CD4+ T cell counts are very low and in the months immediately after CMV retinitis diagnosis.

Canadian consensus guidelines for the management of cytomegalovirus disease in HIV/AIDS

BACKGROUND

The management of HIV-infected patients with cytomegalovirus (CMV) disease has changed significantly with the availability of highly active antiretroviral therapy (HAART).

OBJECTIVES

These updated guidelines are intended to provide practical help to physicians managing HIV-positive patients with or at risk for CMV disease.

METHODS

The 10 members of the Canadian CMV Disease in HIV/AIDS Consensus Group were infectious disease specialists, a primary care physician and ophthalmologists with expertise in HIV and CMV infection. Financial support by Hoffmann-La Roche Canada Ltd was unrestricted, and was limited to travel expenses and honoraria. The consensus group met in June and October 2002. Key areas to be considered were identified, and group members selected, reviewed and presented relevant recent literature for their assigned section for the group's consideration. Evidence was assessed based on established criteria, which were expert opinions of the members. Draft documents were circulated to the entire group and modified until consensus was reached. The final guidelines represent the group's consensus agreement. The guidelines were approved by the Canadian Infectious Disease Society.

RESULTS AND CONCLUSIONS

The guidelines address symptom monitoring, screening for early detection and prevention, and treatment using oral, intravenous and intraocular anti-CMV therapies in conjunction with HAART.

Clinical risk factors for cytomegalovirus retinitis in patients with AIDS

PURPOSE

To determine the clinical risk factors for cytomegalovirus (CMV) retinitis in patients with AIDS.

DESIGN

A case-control study.

PARTICIPANTS

The study included 120 patients in whom CMV retinitis had been diagnosed from 1990 through 1999 (cases) and 159 patients without CMV retinitis from the same period (controls). All individuals had AIDS and CD4 counts less than 50 cells/microl at the time of diagnosis of retinitis in the cases or on the corresponding date for the controls.

METHODS

Clinical risk factors were determined by history or physical examination. Confounders controlled for included CD4 count, hospital center, and a series of variables to control for confounding by drug treatment. Statistical analysis was performed by multivariate logistic regression. A systematic model-building strategy was developed from assumption testing to model building to model checking. MAIN VARIABLES MEASURED: Presence of visual symptoms, retinal microinfarctions (cotton-wool spots), history of opportunistic infections, and risk factors for human immunodeficiency virus acquisition were determined and compared in both groups.

RESULTS

The following clinical risk factors were significant predictors of CMV retinitis: flashing lights or floaters (odds ratio [OR], 11.42; 95% confidence interval [CI], 3.43 to 38.01), cotton-wool spots (OR, 2.90; 95% CI, 1.01 to 8.29), number of previous opportunistic infections (OR, 1.81; 95% CI, 1.24 to 2.64), previous nonocular CMV infection (OR, 82.99; 95% CI, 6.86 to 1004.58), previous Mycobacterium infection (OR, 3.41; 95% CI, 0.99 to 11.85), and homosexuality (OR, 2.83; 95% CI, 1.13 to 7.12).

CONCLUSIONS

Based on this study, clinical variables have been identified that elevate the risk of CMV retinitis. These findings may be useful to clinicians and health policy experts in developing rational guidelines for screening, examination frequency, and targeted prophylaxis for CMV retinitis in patients with AIDS.

Retinal and extraocular cytomegalovirus end-organ disease in HIV-infected patients in Europe: a EuroSIDA study, 1994-2001

This multicentre prospective cohort study by the EuroSIDA study group was designed to determine the factors affecting the incidence of cytomegalovirus (CMV) end-organ disease (CMVD) and the rate of survival after diagnosis in patients with AIDS during the years 1994-2001. This period includes two eras, the pre-HAART era and the HAART era, because HAART affects the natural history of HIV infection, especially with respect to opportunistic infections, including CMV infection. Clinical and laboratory data were collected from the charts of 8,556 patients in 63 AIDS clinics in Europe. A total of 707 patients had CMVD at recruitment and at follow-up: 449 with retinitis (CMVR), 190 with extraocular CMV disease (EOCMVD), and 58 with both. Of the cases of EOCMVD, 66% involved the gastrointestinal tract and 17% the central nervous system. Of patients with a CD4+ count of < or =200 mm(-3) initially, 1.8% on HAART developed CMVD within a 24-month period, as compared to 11.1% on dual therapy and 14.3% without treatment (P<0.0001). There were highly significant differences in survival according to the calendar year (P<0.0001), with mortality declining from 79% during the years 1994-1995 to 42% in 2000-2001. The incidence of death after any CMVD was 28.4 per 100 patient-years of follow-up. Median survival of CMVR patients and EOCMVD patients was 11 and 7 months, respectively, the prognosis being better among patients with gastrointestinal rather than neurological CMVD. The initiation of HAART was associated with a 37% decrease in mortality (P<0.05). Eighteen percent of all deaths were caused by EOCMVD itself. This study describes a decline in the incidence and mortality of CMVR and EOCMVD during the HAART era of the HIV epidemic. It furthermore serves as a reminder of the importance of EOCMVD as a cause of morbidity and mortality in AIDS in the pre-HAART era.

Mortality risk for patients with cytomegalovirus retinitis and acquired immune deficiency syndrome

We prospectively followed up 589 patients to evaluate the relationship of anti-cytomegalovirus (CMV) treatment and immune reconstitution in response to highly active antiretroviral therapy (HAART) on the mortality risk of patients with CMV retinitis and acquired immune deficiency syndrome. The use of HAART was associated with an 81% lower mortality rate (95% confidence interval [CI], 74%-86%); it was 96% lower (95% CI, 92%-98%) for those who developed immune recovery and 49% lower (95% CI, 30-63%) for those who did not. Using time-updated multivariate analysis, current systemic anti-CMV treatment was independently associated with a 28% lower mortality rate (95% CI, 8%-43%). On the basis of these results, for patients who continue to have profound immunodeficiency despite HAART, the continued use of HAART and systemic anti-CMV therapy is predicted to reduce the risk of mortality by 65%, over and above the benefits of Pneumocystis carinii and Mycobacterium avium prophylaxis.

Ocular disposition and tolerance of ganciclovir-loaded albumin nanoparticles after intravitreal injection in rats

Cytomegalovirus (CMV) infection mainly affects endothelial cells of ocular vessels, optic nerve and the retina, resulting in direct or autoimmune damages, uveoretinitis and disturbed vision. The use of colloidal carriers for the intravitreal delivery of ganciclovir may prolong its residence in the eye, minimizing the opacification observed for macroscopic implants. The aim of this work was to evaluate the ocular toxicity induced by the prolonged presence of ganciclovir-loaded bovine serum albumin nanoparticles after their intravitreal injection. The intraocular disposition of these carriers was also studied by immunochemistry. Two weeks post-injection, a significant amount of nanoparticles remained in the vitreous cavity, mainly in a thin layer overlying the retina and in the area close to the blood aqueoUs barrier. Their prolonged residence in the eve seemed to be well tolerated and the histological evaluation of the retina, mainly the photoreceptor layer, and adjacent tissues revealed the absence of inflammatory reactions or alterations in the tissue architecture (i.e. cellular infiltrations or vascular inflammation). In addition, nanoparticles neither alter the expression and distribution of arrestin and rhodopsin autoantigens nor the mineralocorticoid receptor. In summary, the vision was not affected by autoimmune phenomena or alterations in the behavior of ophthalmic cells due to the intravitreal injection of these nanoparticles.

Incidence of primary opportunistic infections in two human immunodeficiency virus-infected French clinical cohorts

BACKGROUND

Clinical guidelines for the prevention of opportunistic infections in human immunodeficiency virus (HIV)-infected individuals have been developed on the basis of natural history data collected in the USA. The objective of this study was to estimate the incidence of primary opportunistic infections in HIV-infected individuals in geographically distinct cohorts in France.

METHODS

We conducted our study on 2664 HIV-infected patients from the Tourcoing AIDS Reference Centre and the hospital-based information system of the Groupe d'Epidémiologie Clinique du SIDA en Aquitaine enrolled from January 1987 to September 1995 and followed through December 1995. We estimated: (1) CD4-adjusted incidence rates of seven primary opportunistic infections in the absence of prophylaxis for that specific infection or any antiretroviral drugs other than zidovudine; and (2) CD4 lymphocyte count decline.

RESULTS

The highest incidence rates for all opportunistic infections studied occurred in patients with CD4 counts < 200/microl. With CD4 counts < 50/microl, the most common opportunistic infections were toxoplasmic encephalitis (12.6 per 100 person-years) and Pneumocystis carinii pneumonia (11.4 per 100 person-years). Mycobacterium tuberculosis was the least common opportunistic infection (< 5.0/100 person-years). Even with CD4 counts > 300/microl, cases of Pneumocystis carinii pneumonia and toxoplasmic encephalitis were reported. The mean CD4 lymphocyte decline per month was 4.6 cells/microl. There was a significant association between HIV risk behaviour and the incidence of cytomegalovirus infection, between calendar year and the incidence of Pneumocystis carinii pneumonia, toxoplasmic encephalitis and Candida esophagitis, and between geographical area and the incidence of Pneumocystis carinii pneumonia and cytomegalovirus infection.

CONCLUSIONS

Geographical differences exist in the incidence of HIV-related opportunistic infections. These results can be used to define local priorities for prophylaxis of opportunistic infections.