Can chemoprophylaxis against opportunistic infections be discontinued after an increase in CD4 cells induced by highly active antiretroviral therapy?

Pyrimethamine 3D printlets for pediatric toxoplasmosis: design, pharmacokinetics, and anti-toxoplasma activity

OBJECTIVES

The focus of the present research is to develop printlet formulations of pyrimethamine (PMT).

METHODS

Printlets formulation of PMT were developed by screening design by varying laser scanning speed, Kollidon® VA 64, polyvinylpyrrolidone, and disintegrant.

RESULTS

Laser scanning speed, Kollidon® VA, and disintegrant had statistically significant effect on hardness, disintegration time, and/or dissolution (p < 0.05). Dissolution was almost 100% in 30 min. X-ray powder diffraction indicated partial amorphous transformation of the crystalline drug. Pharmacokinetic and anti-toxoplasma activity profiles of the printlets and compressed tablets were superimposable with no statistical difference (p > 0.05).

CONCLUSION

Clinical performance of the printlets would be similar to the compressed tablets.

Management of Intraocular Infections in HIV

Purpose: Overview of treatment options for the most common intraocular opportunistic infections in patients with acquired immunodeficiency syndrome (AIDS), including ocular syphilis, ocular tuberculosis, toxoplasmic chorioretinitis, and viral retinitis. Method: Narrative Review. Results: Despite the huge advances in the development of combined antiretroviral therapy (cART) for the management of patients with human immunodeficiency virus (HIV) infection, opportunistic infections still represent a significant diagnostic dilemma and cause of ocular morbidity in patients with HIV. Conclusion: Although the treatment of intraocular infections in patients with AIDS may be challenging, prompt assessment of the clinical features and appropriate aggressive management of the underlying etiology are critical to avoid life and vision threatening.

Discontinuation of primary and secondary prophylaxis for opportunistic infections in HIV-infected patients who had CD4+ cell count <200 cells/mm(3) but undetectable plasma HIV-1 RNA: an open-label randomized controlled trial

Abstract The CDC recommends discontinuing opportunistic infections (OIs) prophylaxis in HIV-infected patients who have CD4+ cell count >200 cells/mm(3) after receiving combination antiretroviral therapy (cART). A prospective randomized controlled trial was conducted at Chiang Mai University Hospital from June 1, 2009 to January 31, 2012 in 74 adult HIV-infected patients who had received cART and had CD4+ cell count <200 cells/mm(3) but plasma HIV-1 RNA<50 copies/ml. Forty-three patients (58.1%) were male and the mean age was 41.8±8.1 years; 68 (91.9%) and 59 (79.7%) patients were receiving co-trimoxazole and antifungal prophylaxis, respectively. The median CD4+ cell counts at enrollment were 142 (IQR 108, 161) and 158 (IQR 141, 176) cells/mm(3) among patients who discontinued and continued OIs prophylaxis, respectively (p value=0.041). One of 37 patients (2.7%) in the discontinuation group developed Pneumocystis jiroveci pneumonia, giving the incidence rate of 1.57/1000 person-months. None of the 37 patients in the continuation group developed OIs. The difference in the prevention rates of OIs between groups was -2.7% (95% CI -7.9, 2.5). In conclusion, in the setting where plasma HIV-RNA measurement is available, e.g., Asia-Pacific region, discontinuation of prophylaxis is considerably safe in HIV-infected patients receiving cART with undetectable plasma HIV-RNA but incomplete immune recovery.

Discontinuation of Pneumocystis jirovecii pneumonia prophylaxis with CD4 count <200 cells/µL and virologic suppression: a systematic review

BACKGROUND

HIV viral load (VL) is currently not part of the criteria for Pneumocystis jirovecii pneumonia (PCP) prophylaxis discontinuation, but suppression of plasma viremia with antiretroviral therapy may allow for discontinuation of PCP prophylaxis even with CD4 count <200 cells/µL.

METHODS

A systematic review was performed to determine the incidence of PCP in HIV-infected individuals with CD4 count <200 cells/µL and fully suppressed VL on antiretroviral therapy but not receiving PCP prophylaxis.

RESULTS

Four articles examined individuals who discontinued PCP prophylaxis with CD4 count <200 cells/µL in the context of fully suppressed VL on antiretroviral therapy. The overall incidence of PCP was 0.48 cases per 100 person-years (PY) (95% confidence interval (CI) (0.06-0.89). This was lower than the incidence of PCP in untreated HIV infection (5.30 cases/100 PY, 95% CI 4.1-6.8) and lower than the incidence in persons with CD4 count <200 cells/µL, before the availability of highly active antiretroviral therapy (HAART), who continued prophylaxis (4.85/100 PY, 95% CI 0.92-8.78). In one study in which individuals were stratified according to CD4 count <200 cells/µL, there was a greater risk of PCP with CD4 count ≤100 cells/µL compared to 101-200 cells/µL.

CONCLUSION

Primary PCP prophylaxis may be safely discontinued in HIV-infected individuals with CD4 count between 101-200 cells/µL provided the VL is fully suppressed on antiretroviral therapy. However, there are inadequate data available to make this recommendation when the CD4 count is ≤100 cells/µL. A revision of guidelines on primary PCP prophylaxis to include consideration of the VL is merited.

Risk of pneumocystosis after early discontinuation of prophylaxis among HIV-infected patients receiving highly active antiretroviral therapy

BACKGROUND

Risk of pneumocystosis after discontinuation of primary or secondary prophylaxis among HIV-infected patients before CD4 counts increase to >==200 cells/microL (early discontinuation) after receiving highly active antiretroviral therapy (HAART) is rarely investigated.

METHODS

Medical records of 660 HIV-infected patients with baseline CD4 counts <200 cells/microL who sought HIV care and received HAART at a university hospital in Taiwan between 1 April, 1997 and 30 September, 2007 were reviewed to assess the incidence rate of pneumocystosis after discontinuation of prophylaxis for pneumocystosis.

RESULTS

The incidence rate of pneumocystosis after HAART was 2.81 per 100 person-years among 521 patients who did not initiate prophylaxis or had early discontinuation of prophylaxis, which was significantly higher than the incidence rate of 0.45 per 100 person-years among 139 patients who continued prophylaxis until CD4 counts increased to >==200 cells/microL (adjusted risk ratio, 5.32; 95% confidence interval, 1.18, 23.94). Among the 215 patients who had early discontinuation of prophylaxis after achievement of undetectable plasma HIV RNA load, the incidence rate of pneumocystosis was reduced to 0.31 per 100 person-years, which was similar to that of the patients who continued prophylaxis until CD4 counts increased to >==200 cells/microL (adjusted risk ratio, 0.63; 95% confidence interval, 0.03, 14.89).

CONCLUSIONS

Compared with the risk of pneumocystosis among patients who continued prophylaxis until CD4 counts increased to >==200 cells/microL after HAART, the risk was significantly higher among patients who discontinued prophylaxis when CD4 counts remained <200 cells/microL, while the risk could be reduced among patients who achieved undetectable plasma HIV RNA load after HAART.

Failure of highly active antiretroviral therapy in reconstituting immune response to Clostridium tetani vaccine in aged AIDS patients

The purpose of this study was to evaluate the impact of age on tetanus-specific immune response in successfully highly active antiretroviral therapy-treated AIDS patients, using healthy age-matched individuals as controls. Whole Peripheral blood mononuclear cells or CD8(+) cell-depleted peripheral blood mononuclear cells from previously tetanus toxoid (TT)-immunized individuals were activated with TT plus IL-2, and cell proliferation, cytokine production, and in vitro HIV-1 replication were measured. The in vivo magnitude of the humoral immune response was also assessed by antibody measurements. Our results showed that, compared with other groups, both in vitro TT-specific lymphoproliferation and serum antibody concentration were lower in older AIDS patients. Although the IL-1beta and tumour necrosis factor alpha (TNF-alpha) production were higher in cultures from aged HIV-1-infected patients, a dramatic damage on the interferon gamma (IFN-gamma) release was observed, when compared with younger patients. CD8(+) T lymphocytes depletion reduced IL-1beta and TNF-alpha release in the older groups, however, it did not significantly alter their IFN-gamma production. Furthermore, the neutralization of endogenous IL-10 did not change the IFN-gamma deficiency in older AIDS patients. Finally, the lower cellular immune response in this patient group was not related to in vitro HIV-1 replication. The results suggest that successfully highly active antiretroviral therapy-treated aged AIDS patients do not reconstitute the immune response to TT, making them probably more susceptible to tetanus even after vaccination.

Interleukin-10-secreting CD4 cells from aged patients with AIDS decrease in-vitro HIV replication and tumour necrosis factor alpha production

OBJECTIVE

To evaluate the impact of age on the proliferative response, cytokine profile and viral kinetics in AIDS patients treated successfully with antiretroviral drugs.

METHODS

Peripheral blood mononuclear cells (PBMC), CD4 cell-depleted PBMC or CD4 T cells from young adult and aged HIV-1-infected patients were activated in vitro with anti-CD3 with or without interleukin (IL)-2. Lymphoproliferation and cytokines were measured after 3 days and in-vitro HIV-1 replication after 7 days.

RESULTS

Both lymphoproliferation and cytokine [IL-1beta, tumour necrosis factor alpha (TNF-alpha) and interferon gamma (IFN-gamma)] secretion were higher in younger than in older AIDS patients. In cultures of cells derived from aged patients and activated by anti-CD3, IFN-gamma production was severely damage and IL-10 production was much higher. Although IL-2 addition to activated PBMC elevated IFN-gamma secretion, IL-10 production remained elevated in the aged group. The depletion of CD4 T lymphocytes from these cultures dramatically reduced released IL-10 in the older group but did not alter significantly IFN-gamma production. Interestingly, higher IL-10 levels produced by CD4 T cells were related to lower in-vitro HIV-1 replication, and the blockade of this cytokine by anti-IL-10 monoclonal antibody enhanced virus replication. This effect may be correlated with elevated TNF-alpha secretion. Finally, impaired IFN-gamma secretion detected in activated CD4 T cells obtained from aged patients was not directly correlated with high IL-10 production.

CONCLUSIONS

Elevated IL-10 production by aged AIDS patients contributed considerably to control of HIV replication and to inhibition of TNF-alpha secretion but not to the reduced IFN-gamma production.

Pneumocystis jiroveci pneumonia prophylaxis is not required with a CD4+ T-cell count < 200 cells/microl when viral replication is suppressed

OBJECTIVE

To determine the safety of discontinuing Pneumocystis jiroveci pneumonia (PCP) prophylaxis, in patients on effective antiretroviral therapy with CD4+ T-cell counts that have plateaued at < 200 cells/microl.

METHODS

We prospectively evaluated a cohort of HIV infected patients at a multidisciplinary HIV clinic with sustained HIV RNA levels < 50 copies/ml and CD4+ T-cell counts that have plateaued at < 200 cells/microl and who have discontinued PCP prophylaxis.

RESULTS

Nineteen patients fulfilled the above criteria. Eleven had been taking daily trimethoprim-sulfamethoxazole, seven were receiving monthly aerosolized pentamidine, and one patient never received any prophylaxis. The median CD4+ T-cell count at the time of discontinuation and at the most recent determination were 120 (range, 34-184) and 138 (range, 6-201) cells/microl, respectively. To date, patients have been off PCP prophylaxis for a mean of 13.7 +/- 10.6 months and a median of 9.0 (range 3-39) months for a total of 261 patient-months. To date, no patient has developed PCP. This is significantly different from the risk of developing PCP with a CD4+ T-cell count of < 200 cells/microl in untreated HIV infection (rate difference 9.2%; 95% confidence interval, 5.7 to 12.8%; P < 0.05).

CONCLUSION

With sustained suppression of viral replication, PCP prophylaxis may not be necessary, regardless of CD4+ T-cell count. This illustrates a degree of immune recovery that occurs with virologic suppression that is not reflected in absolute CD4+ T-cell count or percentage and suggests that guidelines for P. jiroveci pneumonia prophylaxis may need to be re-evaluated.

Late Presentation of HIV-Infected Individuals

Late presentation remains a major concern despite the dramatically improved prognosis realized by ART. We define a first presentation for HIV care during the course of HIV infection as ‘late’ if an AIDS-defining opportunistic disease is apparent, or if CD4+ T-cells are <200/μl. In the Western world, approximately 10 and 30% of HIV-infected individuals still present with CD4+ T-cells <50 and <200/μl, respectively; estimates are substantially higher for developing countries. Diagnosis and treatment of opportunistic diseases and intense supportive in-hospital care take precedence over ART. Benefits of starting ART without delay, that is, when opportunistic diseases are still active, include faster resolution of opportunistic diseases and a decreased risk of recurrence. The downside of starting ART without delay could include toxicity, drug interactions and immune reconstitution inflammatory syndrome (IRIS). Among asymptomatic or oligosymptomatic individuals presenting late, where ART and primary prophylaxis are initiated, ∼10–20% will become symptomatic from drug toxicity or undiagnosed opportunistic complications, including IRIS, which require appropriate therapies. In this review we describe late presentation to HIV care, the scale of the problem, the evaluation of a late-presenting patient and challenges associated with initiation of potent anti-retroviral therapy (ART) in the setting of acute opportunistic infections and other comorbidities.

Evolving characteristics of toxoplasmosis in patients infected with human immunodeficiency virus-1: clinical course and Toxoplasma gondii-specific immune responses

Toxoplasmic encephalitis (TE) is the most important opportunistic infection of the central nervous system in patients infected with human immunodeficiency virus (HIV)-1. This study evaluated the effect of highly active anti-retroviral therapy (HAART) and Toxoplasma gondii-specific immune responses on the occurrence of TE. The clinical characteristics of all patients diagnosed with TE in two centres since 1990 (n = 140) were analysed. Patients were grouped according to the date of diagnosis (period 1, 1990-1993; period 2, 1994-1996; period 3, 1997 onwards). Immune responses to T. gondii were evaluated in a subgroup (n = 12) by interferon (IFN)-gamma-specific ELISPOT tests. There were marked differences in the estimated Kaplan-Meier overall survival (OS), with a 1-year OS (5-year OS) of 41% (7%) in period 1, 56% (29%) in period 2, and 90% (78%) in period 3 (p <0.0001). In period 3, TE was found to be the first AIDS-defining illness more frequently than in earlier periods (74% vs. 38%, p 0.0002). Persistent neurological deficits caused by TE were present in 37% of the patients. Patients with an acute episode of TE or a TE relapse had significantly lower responses in the T. gondii-specific ELISPOT than patients who discontinued maintenance therapy and were relapse-free (p 0.0044). Survival of HIV patients with TE has improved markedly since the introduction of HAART, but persistent neurological deficits are often present in surviving patients. While preventive therapy remains essential, evaluation of T. gondii-specific immune responses may be an important step in improving estimates of the individual risk of TE and TE relapses.

Discontinuation of maintenance therapy against toxoplasma encephalitis in AIDS patients with sustained response to anti-retroviral therapy

Discontinuation of maintenance therapy against toxoplasma encephalitis (TE) for individuals infected with human immunodeficiency virus (HIV) who are receiving successful anti-retroviral therapy is considered safe. Nevertheless, there are few published studies concerning this issue. Within the setting of the Swiss HIV Cohort Study, this report describes a prospective study of discontinuation of maintenance therapy against TE in patients with a sustained increase of CD4 counts to > 200 cells/microL and 14% of total lymphocytes, and no active lesions on cerebral magnetic resonance imaging (MRI). In addition to clinical evaluation, cerebral MRI was performed at baseline, and 1 and 6 months following discontinuation. Twenty-six AIDS patients with a history of TE agreed to participate, but three patients (11%) could not be enrolled because they still showed enhancing cerebral lesions without a clinical correlate. One patient refused MRI after 6 months while clinically asymptomatic. Among the remaining 22 patients who discontinued maintenance therapy, one relapsed after 3 months. During a total follow-up of 58 patient-years, there was no TE relapse among the patients who had remained clinically and radiologically free of relapse during the study. Thus, discontinuation of maintenance therapy against TE was generally safe, but may fail in a minority of patients. Patients who remain clinically and radiologically free of relapse at 6 months after discontinuation are unlikely to experience a relapse of TE.

Discontinuation of primary and secondary Toxoplasma gondii prophylaxis is safe in HIV-infected patients after immunological restoration with highly active antiretroviral therapy: results of an open, randomized, multicenter clinical trial

BACKGROUND

To our knowledge, no randomized trials have evaluated whether prophylaxis against toxoplasmic encephalitis can be safely discontinued after the CD4+ T cell count increases in response to highly active antiretroviral therapy.

METHODS

We conducted a randomized, nonblinded, multicenter clinical trial of the discontinuation of primary or secondary prophylaxis against toxoplasmic encephalitis in human immunodeficiency virus (HIV)-infected patients with a sustained response to antiretroviral therapy (defined as a CD4+ T cell count of > or =200 cells/mm3 and a plasma HIV type 1 [HIV-1] RNA level of <5000 copies/mL for at least 3 months). Prophylaxis was restarted if the CD4+ T cell count decreased to <200 cells/mm3.

RESULTS

The 381 patients receiving primary prophylaxis had a median CD4+ T cell count on study entry of 343 cells/mm3, and 318 (83%) of 381 patients had undetectable HIV-1 RNA in plasma. After a median follow-up period of 25 months (409 person-years), there were no episodes of toxoplasmic encephalitis among the 196 patients who discontinued prophylaxis (at 1 year, the upper limit of the 95% confidence interval for relapse rate was 2.40%). For the 57 patients receiving secondary prophylaxis, the median CD4+ T cell count on entry was 407 cells/mm3, and 49 (86%) of 57 patients had undetectable HIV-1 RNA in plasma. After a median follow-up period of 30.5 months (69 person-years), there were no episodes of toxoplasmic encephalitis among the 28 patients who discontinued prophylaxis (at 1 year, the upper limit of the 95% confidence interval for relapse rate was 16%).

CONCLUSIONS

In HIV-infected adult patients receiving effective highly active antiretroviral therapy, primary and secondary prophylaxis against toxoplasmic encephalitis can be safely discontinued after the CD4+ T cell count has increased to > or =200 cells/mm3 for >3 months.

Immunological recovery and antiretroviral therapy in HIV-1 infection

Potent antiretroviral therapy has dramatically improved the prognosis of patients infected with HIV-1. Primary and secondary prophylaxis against Pneumocystis carinii, Mycobacterium avium, cytomegalovirus, and other pathogens can be discontinued safely once CD4 cell counts have increased beyond pathogen-specific thresholds. Approximately one-third of individuals receiving antiretroviral therapy will not reach CD4 cell counts above 500 cells per muL after 5 years despite continuous suppression of plasma HIV-1 RNA. Whether this failure represents a risk factor for the long-term incidence of opportunistic diseases--eg, tuberculosis or malignancies--remains uncertain. We describe the time course of CD4 cell concentrations in patients whose plasma HIV-1 RNA is durably suppressed by antiretroviral therapy, in patients with incomplete suppression of plasma HIV-1 RNA, and during treatment interruptions. In addition, immune reconstitution disease, an inflammatory syndrome associated with immunological recovery occurring days to weeks after the start of antiretroviral therapy, is briefly described.

Longitudinal trends in antiretroviral use in a cohort of men and women in Ontario, Canada

Initial studies have shown impaired access to antiretrovirals and slower adoption of new therapies by women. It is unclear if similar treatment delays still occur, especially in those with a publicly funded health care system in Ontario, Canada. The objectives of this study were (1) to evaluate longitudinal patterns of antiretroviral use in patients with HIV in Ontario and (2) to determine if gender differences exist in access to and uptake of antiretroviral drugs over time. A retrospective medical chart review was undertaken. One hundred four HIV-positive patients were recruited from nine hospital-based HIV outpatient clinics throughout Ontario. From time of study enrollment in 1999-2001 to the first clinic visit (8.1 +/- 3.2 years; range, 2.3-16.8 years), CD4+ T-cell counts, date of and agents used in initial antiretroviral regimen, and first HAART regimen were evaluated by gender. Kaplan-Meier plots were used to evaluate time to drug initiation from known HIV diagnosis. Serial cross sections of numbers and types of antiretroviral drugs prescribed in March, June, September, and December 1988 to 2001 were also compared as was number of regimens used. There were few differences between men and women in antiretroviral use; both initiated therapy within 2.2 +/- 2.3 years of HIV diagnosis at an average CD4 counts of 300.3 +/- 150.1 cells per microliter. Antiretroviral treatment regimens changed over time, with limited variation by gender. In the period immediately surrounding the first highly active antiretroviral therapy (HAART) recommendations by the U.S. Department of Health and Human Services in July 1997, significantly more antiretroviral drugs were prescribed for men than women. Antiretroviral prescribing in patients attending hospital- based HIV outpatient programs in Ontario is consistent with antiretroviral treatment guidelines over time, without substantial differences in antiretroviral access and use by gender.

Discontinuation of Primary Prophylaxis against Mycobacterium avium Complex Infection in HIV-Infected Persons Receiving Antiretroviral Therapy: Observations from a Large National Cohort in the United States, 1992-2002

In a large, diverse cohort of human immunodeficiency virus (HIV)-infected persons receiving routine care, the proportion of eligible persons who discontinued primary prophylaxis against Mycobacterium avium complex (MAC) infection, according to guidelines of the US Public Health Service and the Infectious Diseases Society of America, increased from 16.7% (in 1996) to 84.9% (in 2002). The discontinuation of primary prophylaxis was not associated with an increased risk of disseminated MAC infection.

Long-term antifungal prophylaxis in high-risk hematopoietic stem cell transplant recipients

The risks for invasive fungal infections, particularly mould infections such as invasive aspergillosis, among hematopoietic stem cell transplant (HSCT) recipients are linked to the duration and severity of myelosuppression and immunosuppression. Strategies to prevent invasive fungal infections have focused primarily on the use of orally administered azole antifungal agents during the neutropenic period rather than on the more prolonged post-engraftment period. The major limitations of these studies included the heterogeneity among the subjects studied for fungal infection risk factors, the agents administered, the dosing, and duration of prophylaxis. More recent studies have attempted to examine the efficacy of antifungal prophylaxis strategies among allogeneic HSCT recipients to day 100 and beyond. It is clear that a variety of products have efficacy in preventing invasive candidiasis, including imidazole and triazole antifungals, low-dose amphotericin B, and the echinocandin, micafungin; however, only the extended spectrum azole, itraconazole, has been shown to impact the incidence of proven invasive aspergillosis. Other extended spectrum azole antifungal agents, voriconazole and posaconazole, are being studied as long-term prophylaxis in high-risk HSCT recipients. While clinical trials have suggested that a duration of prophylaxis against moulds of six months or more may be required, it remains unclear if this is required in all cases. The prophylactic efficacy over time may be linked to the degree of immunosuppression as measured by markers such as the numbers of circulating CD4 T lymphocytes. Concerns about selection for resistant moulds among long-term recipients of these drugs are emerging. The cumulative experience to date suggests that long-term antifungal chemoprophylaxis is feasible and effective when applied in defined circumstances. The concerns about treatment-related toxicities, resistance, and costs are valid.

Long-term safety of discontinuation of secondary prophylaxis against Pneumocystis pneumonia: prospective multicentre study

OBJECTIVES

To assess the long-term safety of discontinuation of secondary anti-Pneumocystis prophylaxis in HIV-infected adults treated with antiretroviral combination therapy and who have a sustained increase in CD4 cell counts.

DESIGN

Prospective observational multicentre study.

PATIENTS AND METHODS

The incidence of P. jirovecii pneumonia after discontinuation of secondary prophylaxis was studied in 78 HIV-infected patients on antiretroviral combination therapy after they experienced a sustained increase in CD4 cell counts to at least 200 x 10(6) cells/l and 14% of total lymphocytes measured twice at least 12 weeks apart.

RESULTS

Secondary prophylaxis was discontinued at a median CD4 cell count of 380 x 10(6) cells/l. The median follow-up period after discontinuation of secondary prophylaxis was 40.2 months, yielding a total of 235 person-years of follow-up. No cases of recurrent P. jirovecii pneumonia occurred during this period. The incidence was thus 0 per 100 person-years with a 95% upper of confidence limit of 1.3 cases per 100 patient-years.

CONCLUSIONS

Discontinuation of secondary prophylaxis against P. jirovecii pneumonia is safe even in the long term in patients who have a sustained immunologic response on antiretroviral combination therapy.

Mycobacterium avium complex in patients with HIV infection in the era of highly active antiretroviral therapy

Disseminated Mycobacterium avium complex (MAC) infection is a common complication of late-stage HIV-1 infection. Since the advent of highly active antiretroviral therapy (HAART), the rate of MAC infection has declined substantially, but patients with low CD4 cell counts remain at risk. Among patients in the Johns Hopkins cohort with advanced HIV disease, the proportion developing MAC has fallen from 16% before 1996 to 4% after 1996, with a current rate of less than 1% per year. Factors associated with developing MAC include younger age, no use of HAART, and enrollment before 1996. Prophylaxis with azithromycin or clarithromycin is recommended for all patients with CD4 counts less than 50 cells/mL. Optimum treatment for disseminated MAC includes clarithromycin and ethambutol, and another investigation suggests that the addition of rifabutin might reduce mortality. Both prophylaxis and treatment of disseminated MAC can be discontinued in patients who have responded to HAART, and specific guidelines for withdrawing treatment have been published. Although HAART has altered the frequency and outcome of MAC infection, it remains an important complication of AIDS.

Disseminated mycobacterium avium-intracellulare complex (MAC) infection in the era of effective antiretroviral therapy: is prophylaxis still indicated?

Before highly active antiretroviral therapies (HAART) were available for the treatment of persons with HIV infection, disseminated Mycobacterium avium-intracellulare complex (MAC) infection was one of the most common opportunistic infections that affected people living with AIDS. Routine use of chemoprophylaxis with a macrolide has been advocated in guidelines for the treatment of HIV-infected individuals if they have a circulating CD4+ cell count of < or =50 cells/microL. In addition, lifelong prophylaxis for disease recurrence has been recommended for those with a history of disseminated MAC infection. The introduction of HAART has resulted in a remarkable decline in the incidence of opportunistic infections and death among persons living with AIDS. Considerable reconstitution of functional immune responses against opportunistic infections can be achieved with HAART. In the case of infection with MAC, there has been a substantial reduction in the incidence of disseminated infections in the HAART era, even in countries where the use of MAC prophylaxis was never widely accepted. Moreover, the clinical picture of MAC infections in patients treated with potent antiretroviral therapies has shifted from a disseminated disease with bacteraemia to a localised infection, presenting most often with lymphadenopathy and osteomyelitis. Data from several recently conducted randomised, double-blind, placebo-controlled trials led to the current practice of discontinuing primary and secondary prophylaxis against disseminated MAC infections at stable CD4+ cell counts >100 cells/microL. These recommendations are still conservative as primary or secondary disseminated MAC infections are only rarely seen in patients who respond to HAART, despite treatment initiation at very low CD4+ cell counts. Potential adverse effects of macrolide therapy and drug interactions with antiretrovirals also metabolised via the cytochrome P450 enzyme system must be critically weighed against the marginal benefit that MAC prophylaxis may provide in addition to treatment with HAART. These authors feel that, unless patients who initiate HAART at low CD4+ cell counts do not respond to HIV-treatment, routine MAC prophylaxis should not be recommended. Nevertheless, the patient population for whom MAC prophylaxis may still be indicated in the era of HAART needs to be identified in prospectively designed clinical trials.

Immune reconstitution in HIV-infected patients

The prognosis of patients infected with human immunodeficiency virus (HIV) type 1 has dramatically improved since the advent of potent antiretroviral therapies (ARTs), which have enabled sustained suppression of HIV replication and recovery of CD4 T cell counts. Knowledge of the function of CD4 T cells in immune reconstitution was derived from large clinical studies demonstrating that primary and secondary prophylaxis against infectious agents, such as Pneumocystis jirovecii (Pneumocystis carinii), Mycobacterium avium complex, cytomegalovirus, and other pathogens, can be discontinued safely once CD4 T cell counts have increased beyond pathogen-specific threshold levels (usually >200 CD4 T cells/mm3) for 3-6 months. The downside of immune reconstitution is an inflammatory syndrome occurring days to months after the start of ART, with outcomes ranging from minimal morbidity to fatal progression. This syndrome can be elicited by infectious and noninfectious antigens. Microbiologically, the possible pathogenic pathways involve recognition of antigens associated with ongoing infection or recognition of persisting antigens associated with past (nonreplicating) infection. Specific antimicrobial therapy, nonsteroidal anti-inflammatory drugs, and/or steroids for managing immune reconstitution syndrome should be considered.

Prevention of opportunistic infections in adult and adolescent patients with HIV infection. GESIDA/National AIDS Plan guidelines, 2004 [correction]

OBJECTIVE

To provide an update of guidelines from the Spanish AIDS Study Group (GESIDA) and the National AIDS Plan (PNS) committee on the prevention of opportunistic infections in adult and adolescent HIV-infected patients.

METHODS

These consensus recommendations have been produced by a group of experts from GESIDA and/or the PNS after reviewing the earlier document and the scientific advances in this field in the last years. The system used by the Infectious Diseases Society of America and the United States Public Health Service has been used to classify the strength and quality of the data.

RESULTS

This document provides a detailed review of the measures for the prevention of infections caused by viruses, bacteria, fungi and parasites in the context of HIV infection. Recommendations are given for preventing exposure and for primary and secondary prophylaxis for each group of pathogens. In addition, criteria are established for the withdrawal of prophylaxis in patients who respond well to highly active antiretroviral therapy (HAART).

CONCLUSIONS

HAART is the best strategy for the prevention of opportunistic infections in HIV-positive patients. Nevertheless, prophylaxis is still necessary in countries with limited economic resources, in highly immunodepressed patients until HAART achieves beneficial effects, in patients who refuse to take or who cannot take HAART, in those in whom HAART is not effective, and in the small group of infected patients with inadequate recovery of CD4+ T lymphocyte counts despite good inhibition of HIV replication.

Pneumocystis jiroveci Pneumonia in Adult Patients with AIDS

Pneumocystis jiroveci (P. carinii) is an opportunistic pathogen that has gained particular prominence since the onset of the AIDS epidemic. Among several important advances in diagnosis and management, appropriately targeting chemoprophylaxis to HIV-infected patients at high clinical risk for P. jiroveci pneumonia and the introduction of effective combination anti-retroviral therapy (including highly active antiretroviral therapy [HAART]) have contributed to the reduced incidence of P. jiroveci pneumonia. Despite the success of these clinical interventions, P. jiroveci pneumonia remains the most common opportunistic pneumonia and the most common life-threatening infectious complication in HIV-infected patients. Trimethoprim/sulfamethoxazole (cotrimoxazole) remains the first-line agent for effective therapy and chemoprophylaxis, and corticosteroids represent an important adjunctive agent in the treatment of moderate-to-severe P. jiroveci pneumonia. However, problems of chemoprophylaxis and treatment failures, high rates of adverse drug reactions and drug intolerance to first-line antimicrobials, high rates of relapse or recurrence with second-line agents, and newer concerns about the development of P. jiroveci drug resistance represent formidable challenges to the management and treatment of AIDS-related P. jiroveci pneumonia. With the expanding global problem of HIV infection, the intolerance or unavailability of HAART to many individuals and limited access to healthcare for HIV-infected patients, P. jiroveci pneumonia will remain a major worldwide problem in the HIV-infected population. New drugs under development as anti-Pneumocystis agents such as echinocandins and pneumocandins, which inhibit beta-glucan synthesis, or sordarins, which inhibit fungal protein synthesis, show promise as effective agents. Continued basic research into the biology and genetics of P. jiroveci and host defense response to P. jiroveci will allow the development of newer antimicrobials and immunomodulatory therapeutic agents to more effectively treat life-threatening pneumonia caused by this organism.

Hospitalized HIV-infected patients in the HAART era: a view from the inner city

To evaluate hospitalizations of HIV-infected patients in the highly active antiretroviral therapy (HAART) era, we analyzed 2736 admissions of 1562 HIV-infected patients to Cook County Hospital from September 20, 1999 to July 10, 2002. Patients were predominantly African American (81%), male (72%), and active substance abusers (74%). Only 48% of patients with a prior HIV diagnosis were taking HAART and 37% of them had a viral load less than 1000 copies per milliliter. Patients on protease inhibitor (PI)-sparing regimens more frequently achieved a viral load less than 1000 copies per milliliter than those on a PI-containing regimens (41% vs. 34% p = 0.036). For patients with CD4 cell counts less than 200 cells per milliliter, those not taking HAART were more likely African American (83% vs. 76%, p < 0.031), homeless (13% vs. 5%, p < 0.001), active substance abusers (79% vs. 65%, p < 0.001), female (28% vs. 22%, p = 0.001), new to the hospital system (19% vs. 6%, p < 0.001), or not recently seen in the outpatient clinic (42% vs. 17%, p < 0.001). In our population, active substance abuse was prevalent and only a minority of patients was taking HAART. Women were receiving HAART less often, independent of race and substance abuse. Aggressive programs are needed in high-risk populations to address substance abuse issues and to improve patient use of HAART.

Pulmonary considerations in the immunocompromised patient

The compromised patient who presents to the emergency department with pulmonary complaints is becoming a common occurrence. An immunocompromised state can result from a disease process such as HIV or from medications used to prevent graft rejection in solid organ recipients or to treat conditions such as collagen vascular disease. The emergency department physician should be familiar with the more common complications that can afflict this unique patient group. This article addresses the presentation, evaluation, and treatment of the more common pulmonary complications that can occur in solid organ transplant recipients, cancer patients, patients suffering from collagen vascular disease, and patients with HIV disease.

Discontinuation of secondary prophylaxis for Pneumocystis carinii pneumonia in human immunodeficiency virus-infected patients: a randomized trial by the CIOP Study Group

This subgroup analysis assessing secondary prophylaxis for Pneumocystis carinii pneumonia (PCP) describes a multicenter, open-labeled, randomized, controlled trial evaluating the discontinuation of PCP prophylaxis. The main inclusion criterion was a history of PCP and an increase in the CD4 cell count to >200 cells/microL associated with receipt of highly active antiretroviral therapy for >or=3 months. The primary end point was the development of definitive or presumptive PCP. A total of 146 patients were enrolled (77 in the treatment discontinuation arm). After >2 years, 1 definitive and 1 presumptive case of PCP were observed, both of which occurred in patients who discontinued therapy. In most patients, secondary prophylaxis for PCP can be safely discontinued after potent antiretroviral therapy is initiated, but the threshold of >200 CD4 cells/microL may not be considered absolutely safe. Patients who present with symptoms after discontinuation of secondary prophylaxis should be evaluated for PCP despite high CD4 count and complete virus suppression.

The naive CD4+ count in HIV-1-infected patients at time of initiation of highly active antiretroviral therapy is strongly associated with the level of immunological recovery

Current antiretroviral therapy can induce considerable, sustained viral suppression followed by immunological recovery, in which naive CD4 + cells are important. Long-term immunological recovery was investigated during the first 3 y of highly active antiretroviral therapy (HAART) in 210 HIV-1-infected patients. The focus was on the naive CD4 + cell time course and associations between naive CD4 + cell counts and established prognostic markers. Total and naive CD4 + cell counts were measured using flow cytometry. The HIV-RNA detection limit was 20 copies/ml. During 36 months of HAART, the total CD4 + count followed a triphasic pattern, reflecting an initial phase of rapid redistribution from lymphoid tissues, followed by a slow increase, partially due to an increase in naive CD4+ cell count. From Month 18 onwards, both naive and total CD4 + cell counts stabilized, although viral suppression was sustained. There was no association between plasma viral load and the increase in naive CD4 + cell count. Importantly, baseline naive CD4 + cell count was significantly associated with the change in naive CD4 + cell count, suggesting that the naive cell count at baseline does influence the immunological recovery that can be obtained from treatment. Surprisingly, the naive CD4 + cell count tended to stabilize at a subnormal level after 18 months of HAART. This finding merits further investigation.

Response to two consecutive protease inhibitor combination therapy regimens in a cohort of HIV-1-infected children

The response to 2 consecutive protease inhibitor (P1) combination regimens was evaluated in a cohort of HIV-1-infected children. Twelve children, most of whom had been heavily treated, received a 3-drug treatment: saquinavir in hard gelatin capsules (SQVhgc) + zidovudine (ZDV) + didanosine. When this treatment failed it was replaced by a 4-drug regimen: ritonavir + SQVhgc + ZDV + lamivudine. A mild and temporary decrease in viral load (VL) was observed with the initial regimen (p = 0.22). Therapy failure occurred in 7 patients (58%) within 9 months and in another 3 (25%) within 9-18 months. The 7 children who failed within 9 months received the subsequent boosted regimen, leading to a significant and lasting reduction in VL (p = 0.001). None of the patients failed on the boosted regimen: 5/7 achieved a VL of < 400 copies/ml and 3/7 achieved a VL of < 50 copies/ml. Our results suggest that a 4-drug regimen including 2 PIs produces a better and more sustained response than a 3-drug regimen including only 1 PI, and that a good, sustained response is possible with subsequent boosted regimens even in heavily treated children.

Reconstitution of immune responses to tuberculosis in patients with HIV infection who receive antiretroviral therapy

STUDY OBJECTIVE

s: To assess the restoration of immune responses to tuberculosis, as manifested by secretion of T-helper type 1 cytokines (interferon [IFN]-gamma, interleukin [IL]-12, and IL-2) and T-helper type 2 cytokines (IL-10), in HIV-positive patients who receive antiretroviral therapy (ART).

DESIGN

Prospective cohort study.

SETTING

University hospital.

PATIENTS

Ten HIV-positive patients, all naïve to ART and all about to start ART for clinical indications, and 11 healthy, HIV-negative control subjects.

INTERVENTIONS

Assessment of T-cell proliferation and cytokine production after administration of ART to patients with HIV infection.

MEASUREMENTS AND RESULTS

All patients had a negative tuberculin skin test result at baseline and were anergic. Highly active ART reduced the viral load to very low levels in all patients within a short time after starting therapy. Blood samples were drawn every 2 months after starting therapy, and continued for 1 year while the patients continued to receive ART. There were trends toward increased proliferation of peripheral blood mononuclear cells (PBMCs) in response to Mycobacterium tuberculosis-specific stimuli, but these were delayed until several months of ART had elapsed. Similar trends were noted in relation to the secretion of IFN-gamma. Neither PBMC proliferation nor IFN-gamma secretion reached levels seen in healthy control subjects. No consistent trends in IL-2, IL-10, or IL-12 production were noted.

CONCLUSION

ART restores immune responses to M tuberculosis, although this restoration is delayed and does not reach levels seen in healthy, HIV-negative control subjects. These results may explain in part the phenomenon of paradoxic reactions to antituberculosis therapy in patients with HIV infection. A larger study in which patients are followed up for a longer period of time will allow the magnitude and timing of this reconstitution to be more precisely defined.

Management of Opportunistic Infection Prophylaxis in the Highly Active Antiretroviral Therapy Era

Prophylaxis and maintenance therapy against opportunistic infections are a mainstay of management of HIV-infected patients and have led to a significant improvement in quality of life and survival. Antiretroviral combination therapy (ART) has markedly changed the natural course of HIV infection. Incidence of opportunistic infections (OIs) has declined and survival after an OI has improved. Achieving a CD4 count of 200 cells/L after 6 months of ART is a valuable marker for low risk of OI afterwards. Therefore, recommendations on prophylaxis and maintenance therapy need to be redefined. Criteria for discontinuation, such as a CD4 count rise above threshold values and time above threshold values as response to ART, should be evaluated for the most frequent OIs. Reliable data in favor of discontinuation of primary prophylaxis against Pneumocystis carinii pneumonia, toxoplasmic encephalitis, and Mycobacterium avium infection have been published. Discontinuation of maintenance therapy against P. carinii pneumonia is possible, and may be safe against cytomegalovirus retinitis, M. avium, and cryptococcosis and toxoplasmosis in selected patients. Pharmacologic interactions between drugs used for OI prophylaxis and antiretroviral drugs need to be taken into account.

CD4+ T-lymphocyte nadir and the effect of highly active antiretroviral therapy on phenotypic and functional immune restoration in HIV-1 infection

To evaluate the effects of the timing of highly active antiretroviral therapy (HAART) on immune reconstitution, we compared lymphocyte subpopulations and lymphocyte proliferation (LP) in response to Candida albicans, cytomegalovirus, HIV p24, Mycobacterium avium complex, pokeweed mitogen, streptokinase, and tetanus toxoid in 43 patients with pretherapy advanced, moderately advanced, and early chronic HIV-1 infection. All patients had recent CD4+ T-cell counts >450/microl and HIV RNA <400 copies/ml for >12 months. CD4+ nadirs were positively correlated with recent numbers of CD4+ T-cells (P < 0.001), memory cells (P < 0.001), and naïve CD4+ T-cells (P < 0.05) and CD4+ CD28+ T-lymphocytes (P < 0.05) and were negatively correlated with recent CD8+ T-lymphocyte counts (P < 0.05). Only CD4+ naïve T-cells normalized when HAART was initiated at lower CD4+ T-cell levels. Fifty-three percent of patients had LP responses to HIV p24 antigen. While LP responses to prevalent antigens were usually present, responses to tetanus toxoid were more common with higher CD4+ T-lymphocyte nadirs (P < 0.05). Delaying HAART may limit phenotypic and functional immune restoration in HIV-1 infection.

Clinical indicators of immune restoration following highly active antiretroviral therapy

The course of human immunodeficiency virus (HIV) disease is characterized by a progressive decline in immune function. The advent of highly active antiretroviral therapy (HAART) has allowed patients to experience a significant degree of immune restoration when compared with the era before the availability of HAART. Multiple studies, which have employed sophisticated in vitro measures of immune function, have demonstrated improvement in CD4(+) lymphocyte (T4) responses to various opportunistic pathogens. In addition, for patients treated during acute HIV infection, HIV-specific T4 responses have been restored. By contrast, there are a limited number of in vivo measures of T4 function available to assess immune recovery following initiation of HAART. The primary measurement is an increase in CD4 lymphocyte count, the significance of which may be underappreciated. Delayed-type hypersensitivity testing to recall antigens and serological response to prophylactic vaccines may also have a role. This review discusses available markers of immune function and offers suggestions regarding their use in HAART recipients.

Sustained cytomegalovirus-specific CD4+ T cell response associated with prevention of recurrence of cytomegalovirus retinitis without secondary prophylaxis after highly active antiretroviral therapy in patients with AIDS

It has been demonstrated that the cytomegalovirus (CMV)-specific CD4(+) T cell response could be restored after ganciclovir and highly active antiretroviral therapy (HAART) in AIDS patients. In this study, we first confirmed the above observation cross-sectionally. We then performed a prospective longitudinal study over a period of 48 weeks. The second study included nine patients. All patients had received HAART. Five patients had a history of retinitis that was, however, under control after discontinuation of anti-CMV therapy more than 1 year before this study (group A). The other four had active CMV retinitis at the start of this study and anti-CMV therapy was required to control retinitis (group B). Median periods between commencement of HAART and the start of this study in group A and in group B were 27 and 4.5 months, respectively. Within both groups, the number of CD4(+) T cells that produced tumor necrosis factor alpha in response to CMV antigen did not vary throughout the observation period (Friedman test; p > 0.05). However, the median number of responsive CD4(+) T cells in group A patients was significantly higher than in group B (p < 0.05). Our results demonstrate that the number of CMV-responsive CD4(+) T cells increased when HIV was well controlled with HAART and was then maintained, and suggest that these cells may play an important role in the control of retinitis in patients with AIDS.

Pulmonary manifestations of HIV infection in the era of highly active antiretroviral therapy

STUDY OBJECTIVES

To determine whether the spectrum of HIV-related pulmonary disease seen by a university medical center Pulmonary and Critical Care Medicine Service has changed since the introduction of highly active antiretroviral therapy (HAART).

DESIGN

Retrospective chart review.

SETTING

A tertiary care university hospital.

PATIENTS

All HIV-infected patients referred to the Pulmonary and Critical Care Medicine Service from January 1, 1993, through December 31, 1995 (era 1) and from July 1, 1997, through June 30, 2000 (era 2).

INTERVENTIONS

Inpatient and outpatient charts were reviewed for data regarding patient demographics, CD4 cell counts, viral load levels, duration of HIV seropositivity, history of opportunistic infections, and final diagnosis.

RESULTS

Pneumocystis carinii pneumonia (PCP) was less common in the HAART era than in the pre-HAART era, whereas bacterial pneumonia and non-Hodgkin's lymphoma (NHL) were more common in the HAART era than in the pre-HAART era. HAART was protective against PCP (odds ratio [OR], 0.37; confidence interval [CI], 0.16 to 0.89) in a manner dependent on the CD4 cell count. Patients receiving HAART were at increased risk for the development of bacterial pneumonia (OR, 2.41; CI, 1.12 to 5.17) and NHL (OR, 15.11; CI, 3.14 to 28.32). A history of PCP indicated a risk factor for bacterial pneumonia (OR, 2.14; CI, 1.13 to 4.04). A history of cytomegalovirus infection indicated a risk factor for NHL (OR, 6.0; CI, 1.27 to 28.32).

CONCLUSIONS

There have been significant changes in the spectrum of HIV-related pulmonary complications seen by our Pulmonary and Critical Care Medicine Service in the HAART era.

Declining levels of rescued lymphoproliferative response to human cytomegalovirus (HCMV) in AIDS patients with or without HCMV disease following long-term HAART

OBJECTIVE

To investigate the lymphoproliferative response (LPR) to human cytomegalovirus (HCMV) in two groups of AIDS patients undergoing long-term highly active antiretroviral therapy (HAART): group 1 ( n = 22) with nadir CD4(+) cell count <50/microl and no HCMV disease; group 2 ( n = 16) with <50/microl CD4(+) T-cell count and HCMV disease. All patients had previously undergone antiretroviral monotherapy or dual therapy before initiating HAART.

STUDY DESIGN AND METHODS

The two groups of patients were tested prospectively for CD4(+) T cell count, HIV RNA load, HCMV viremia, and LPR to HCMV at baseline, and then after 3 and 4 years of HAART. A control group of 13 recently diagnosed treatment-naive AIDS patients with CD4(+) T-cell counts <100/microl was also investigated.

RESULTS

No LPR to HCMV was found in any of the treatment-naive patients nor in any patient of the two groups examined at baseline, when HCMV viremia was 13.6% in the patient group without disease and 87.5% in the group with disease ( p <.0001). After 3 years of HAART, the frequency of patients who recovered an LPR to HCMV was not significantly different (81.8% in the group without HCMV disease, and 68.7% in the group with HCMV disease), whereas, compared with baseline, the HIV load decreased and the CD4(+) T-cell count increased significantly and to a comparable extent in the two groups of patients. In addition, the frequency of patients with HCMV viremia, although reduced, became comparable in both groups. After 4 years of HAART, the frequency of responders to HCMV without and with HCMV disease dropped to comparable levels (50.0 vs. 56.3%, respectively) in association with high median CD4(+) T-cell counts and low median HIV RNA plasma levels. In parallel, the frequency of patients with HCMV viremia did not change significantly. In addition, after between 3 and 4 years of HAART, although the frequency of stable responders and nonresponders remained unchanged (50%) in both groups, most of the remaining patients showed declining levels of responsiveness to HCMV. Although some patients from both groups were found to have CD4(+) T-cell counts >150/microl in the absence of LPR to HCMV, thus suggesting dissociation of specific and nonspecific immune reconstitution, a significant correlation was found between CD4(+) T-cell count and LPR to HCMV (r = 0.44; p <.001). From a clinical standpoint, anti-HCMV therapy could be safely discontinued in 8 patients with HCMV retinitis showing CD4(+) T-cell counts >150/microl, recovery of HCMV LPR, and no HCMV viremia.

CONCLUSIONS

Declining levels of the previously recovered LPR to HCMV are often observed after long-term HAART. However, because the role of LPR in the evolution of HCMV infection and disease during HAART remains to be defined, the clinical impact of the declining LPR to HCMV must still be clarified in long-term prospective studies.

Discontinuation of Pneumocystis carinii prophylaxis in patients infected with human immunodeficiency virus: a meta-analysis and decision analysis

We performed a meta-analysis and a decision analysis on the discontinuation of prophylaxis for Pneumocystis carinii pneumonia (PCP) in patients infected with human immunodeficiency virus who had adequate immune recovery while receiving highly active antiretroviral therapy. In the meta-analysis (14 studies with 3584 subjects who had discontinued prophylaxis), 8 cases of PCP occurred during 3449 person-years (0.23 cases per 100 person-years [95% confidence interval, 0.10-0.46]). In the decision analysis, mortality and time spent alive without immunodeficiency in the modeled discontinuation strategy were similar to those in the continuation strategy. For patients who received primary prophylaxis, the discontinuation strategy led to slightly fewer episodes of PCP and fewer toxicity-related prophylaxis withdrawals (e.g., 8.6 vs. 34.5 cases per 100 patients during a 10-year period). Patients on the discontinuation strategy were more likely to be receiving trimethoprim-sulfamethoxazole when they became immunodeficient. Comparative results were similar for patients with prior PCP. Discontinuation of PCP prophylaxis in patients with adequate immune recovery is a useful strategy that should be widely considered.

Incidence and risk factors for toxoplasmic encephalitis in human immunodeficiency virus-infected patients before and during the highly active antiretroviral therapy era

The occurrence of toxoplasmic encephalitis (TE) was studied among 19,598 and 17,016 patients enrolled in the French Hospital Database on human immunodeficiency virus whose CD4 cell counts decreased to < or =200x10(6) cells/L before (1992-1995) or after (1996-1998) the availability of highly active antiretroviral therapy, respectively. The incidence of TE decreased from 3.9 cases per 100 person-years in the first period (95% confidence interval [CI], 3.7-4.1) to 1.0 cases per 100 person-years in the second period (95% CI, 0.9-1.1). After adjustment for known risk factors for TE, patients who received cotrimoxazole prophylaxis had a lower risk of TE (adjusted relative hazard, 0.6 and 0.5, respectively, for the first and second periods; P < .001). For patients treated with cotrimoxazole at inclusion, discontinuation of cotrimoxazole increased the risk of TE in both periods (adjusted relative hazard, 4.8 and 4.2, respectively; P < .001). Among patients whose CD4 cell counts increased to > 200 x 10(6) cells/L while undergoing highly active antiretroviral therapy, the incidence of TE was 0.1 cases per 100 person-years (95% CI, 0.0-0.2) and was not increased by discontinuation of cotrimoxazole.

The effect of highly active antiretroviral therapy on cervical cytologic changes associated with oncogenic HPV among HIV-infected women

OBJECTIVE

Cervical intraepithelial neoplasia (CIN), a common condition among HIV-infected women, has been linked to HIV load and immune status. Highly active antiretroviral therapy (HAART) improves immunologic and virologic status. This study was undertaken to determine the relationship between HAART use and CIN.

DESIGN

Cohort study. The Women's Interagency HIV Study (WIHS) in five cities in the USA (Bronx/Manhattan, New York; Brooklyn, New York; Chicago, Illinois; Los Angeles, California; San Francisco Bay area, California; Washington, District of Columbia).

METHODS

HIV-infected women were followed every 6 months with Papanicolaou smears and cervicovaginal lavage for human papillomavirus (HPV) DNA testing. To characterize exposures that changed over time and to capture the dynamic nature of cytologic changes, Papanicolaou smear findings from each participant's consecutive visits were defined as a pair. We determined the proportion of all pairs that exhibited either regression or progression, according to HAART exposure, HPV results and Papanicolaou smear status. As participants could contribute multiple pairs, inferences were based on robust methods to adjust for correlated observations.

RESULTS

Women with persistent HPV infection were more likely to have progression of their lesions. After adjustment for CD4 cell count and Papanicolaou smear status, women on HAART were 40% (95% confidence interval, 4-81%) more likely to demonstrate regression and less likely (odds ratio, 0.68; 95% confidence interval, 0.52-0.88) to demonstrate progression

CONCLUSIONS

HAART altered the course of HPV disease in HIV-infected women, reducing progression and increasing regression. As HPV disease is a common sex-specific manifestation of HIV disease this effect of HAART would be a major additional benefit from this modality of therapy.

Baseline antiretroviral drug susceptibility influences treatment response in patients receiving saquinavir-enhancing therapy

PURPOSE

To relate baseline plasma HIV genotypic and virtual phenotypic antiretroviral drug susceptibility to subsequent virological response in patients receiving saquinavir (SQV)-enhancing therapy. Individuals were randomized to receive stavudine (d4T), SQV, and one of ritonavir, nelfinavir, or delavirdine to enhance SQV blood levels.

METHOD

The protease and reverse transcriptase baseline sequences of 31 treatment-experienced patients were analyzed by genotype and virtual phenotype and were related to viral load at weeks 12 and 24. Genotypic resistance to SQV was defined by the presence of G48V and/or L90M mutations in the protease gene. Potential cross-resistance to d4T in zidovudine (ZDV)-experienced individuals was defined by the presence of thymidine-associated mutations in the reverse transcriptase gene.

RESULTS

ZDV-associated mutations did not affect the virological response at 24 weeks. Individuals who were sensitive to SQV at baseline as determined by either genotyping or virtual phenotyping showed a greater decrease in viral load at week 24 than those resistant to SQV, irrespective of treatment arm. By genotyping, SQV-sensitive individuals had a median log decrease of 1.12 compared to 0.32 for those individuals who were SQV resistant. By virtual phenotyping, SQV-sensitive individuals had a median log decrease of 1.0 compared to a rise of 0.08 in resistant individuals.

CONCLUSION

Thymidine analogue-associated mutations at baseline did not influence the response to subsequent therapy involving d4T. Individuals who were sensitive or resistant to SQV by genotyping or virtual phenotyping responded to SQV-enhancing regimens, but the virological response was greater in those who were sensitive.

Comparative analysis of human cytomegalovirus-specific CD4(+) T-cell frequency and lymphoproliferative response in human immunodeficiency virus-positive patients

Evaluation of human cytomegalovirus (HCMV)-specific T-helper immunity could contribute in optimizing anti-HCMV therapy in human immunodeficiency virus (HIV)-infected patients. Testin the lymphoproliferative response (LPR) is the standard technique used to evaluate T-helper response, but its use in the routine diagnostic laboratory setting can be problematic. The most promising new alternative technique is the determination of HCMV-specific CD4(+) T-cell frequency by flow cytometry detection of intracellular cytokine production after short-term antigen-specific activation of peripheral blood mononuclear cells. HCMV-specific LPR and CD4(+) T-cell frequency were compared in a group of 78 blood samples from 65 HIV-infected patients. The results showed concordance in 80.7% of samples. In addition, comparative analysis of sequential blood samples from 13 HIV-infected patients showed that while in about half of patients the T-helper HCMV-specific immune response remained stable during highly active antiretroviral therapy (HAART), in the other half declining levels of the HCMV-specific CD4(+)-mediated immune response were determined by either one or both assays. In conclusion, our data suggest that the determination of HCMV-specific CD4(+) T-cell frequency can be considered a valuable alternative to the LPR test for the detection of HCMV-specific T-helper response in HIV-infected patients. It could facilitate wider screening of anti-HCMV T-helper activity in HIV-infected patients, with potential benefits for clinicians in deciding strategies of discontinuation or maintenance of anti-HCMV therapy.

Cytomegalovirus infection: the point in 2001

The incidence of cytomegalovirus (CMV) disease, one of the most prevalent opportunistic infections in HIV-infected persons in the early 1990s, has decreased by more than 80% since the introduction of highly active antiretroviral therapy (HAART). The rare cases of CMV disease still observed in Western countries occur mainly in profoundly immunosuppressed patients who have failed to respond to HAART. A new finding is the occasional occurrence of inflammatory retinitis in some patients on HAART with a history of healed retinitis. New tools for CMV detection have become available recently, including use of polymerase chain reaction (PCR) to detect CMV DNA from plasma. It has been possible to redefine, in the HAART period, patients at risk for CMV disease as those who have a low CD4 cell count as well as a blood marker of CMV blood dissemination (plasma CMV DNAaemia or high pp65 antigenaemia). Besides the classical therapeutic approach using ganciclovir (GCV), foscarnet and cidofovir, development of valganciclovir (VGCV), an orally administered prodrug of GCV, appears promising. There is evidence to suggest that it is as effective as intravenous GCV for the treatment of CMV retinitis, and it is currently being studied as a pre-emptive therapy in patients at high risk for CMV disease. Finally, patients with inactive CMV retinitis receiving HAART and with stable immune reconstitution may be able to discontinue maintenance therapy provided a regular ophthalmological and virological surveillance is maintained.

Randomized salvage therapy with saquinavir-ritonavir versus saquinavir-nelfinavir for highly protease inhibitor-experienced HIV-infected patients

PURPOSE

To compare saquinavir + ritonavir and saquinavir + nelfinavir with nucleoside recycling in patients with multiple failures of highly active antiretroviral therapy (HAART).

METHOD

This was a prospective, multicenter, randomized open trial. Inclusion criteria were the following: consent, age > 18, previous protease inhibitor (PI) exposure > 6 months, unchanged HAART > 3 months, and viral load > 3 log. The treatments compared were ritonavir 200 mg bid + saquinavir 600 mg bid (Rito-Saq), and nelfinavir 1,000 mg bid + saquinavir 600 mg bid (Nelf-Saq). Nucleoside analogues were recycled, and nonnucleoside inhibitors were not permitted. Trough levels of the three drugs were measured by high-performance liquid chromatography at the month 3 visit. After the study had been completed, genotyping analysis was done on the first serum at entry.

RESULTS

The study was interrupted due to the availability of new anti-HIV drugs. A random sample of 31 (16 Rito-Saq and 15 Nelf-Saq) patients was divided into two groups, which were comparable in terms of demographic data and previous history of HIV infection. Mean CD4 cell count and plasma viral load (pVL) were 316 +/- 169 and 3.89 +/- 0.87 for Rito-Saq and 448 +/- 238 and 3.85 +/- 0.32 for Nelf-Saq. Previous duration of PI exposure was 31 months for both groups. The mean number of protease gene mutations was 3.8 (range, 2-7) and 4.4 (range, 2-9), respectively. On intention-to-treat (ITT) analysis at month 6, pVL stabilization or decrease >/= 0.5 log was observed in 18 patients (58%): 10 for Rito-Saq and 8 for Nelf-Saq. In a multivariate logistic regression analysis, virological success at month 3 was inversely correlated to baseline viral load (R = 0.14; 95% CI 0.03-2.9; p =.01); and at month 6, virological success was inversely associated to the number of mutations in the protease gene (R = 2.2; 95% CI 0.73-6.53; p =.06).

CONCLUSION

Nelf-Saq and Rito-Saq combinations can be proposed in case of multiple HAART failures. The fact that the virological response was inversely correlated to baseline viral load makes the case for an early switch after a HAART failure.

A prospective study of discontinuing primary and secondary Pneumocystis carinii pneumonia prophylaxis after CD4 cell count increase to > 200 x 106 /l

OBJECTIVE

To assess the incidence of Pneumocystis carinii pneumonia (PCP) after discontinuation of either primary or secondary prophylaxis.

DESIGN

This was a prospective, non-randomized, non-blinded study.

SETTING

Twenty-five University-based AIDS Clinical Trials Group units.

PARTICIPANTS

Participants either had a CD4 cell count < or = 100 x 106/l at any time in the past and no history of confirmed PCP (group I; n = 144), or had a confirmed episode of PCP > or = 6 months prior to study entry (group II; n = 129). All subjects had sustained CD4 cell counts > 200 x 106/l in response to antiretroviral therapy.

INTERVENTIONS

Subjects discontinued PCP prophylaxis within 3 months or at the time of study entry. Evaluations for symptoms of PCP and CD4 cell counts were performed every 8 weeks. Prophylaxis was resumed if two consecutive CD4 cell counts were < 200 x 106/l.

MAIN OUTCOME MEASURE(S)

The main outcome was development of PCP.

RESULTS

No cases of PCP occurred in 144 subjects (median follow-up, 82 weeks) in group I or in the 129 subjects (median follow-up, 63 weeks) in group II (95% upper confidence limits on the rates of 1.3 per 100 person-years and 1.96 per 100 person-years for groups I and II, respectively). Eight subjects (five in group I and three in group II) resumed PCP prophylaxis after two consecutive CD4 cell counts < 200 x 106/l.

CONCLUSIONS

The risk of developing initial or recurrent PCP after discontinuing prophylaxis is low in HIV-infected individuals who have sustained CD4 cell count increases in response to antiretroviral therapy. Neither lifelong primary nor secondary PCP prophylaxis is necessary.