1999 USPHS/IDSA guidelines for the prevention of opportunistic infections in persons infected with Human Immunodeficiency Virus. USPHS/IDSA Prevention of Opportunistic Infections Working Group. Infectious Diseases Society of American

Pneumocystis Carinii Pneumonia in Adult Non-HIV Disorders

Pneumocystis carinii pneumonia (PCP) remains a serious infection in the immunocompromised host (in the absence of HIV infection) and presents significant management and diagnostic challenges to ICU physicians. Non-HIV PCP is generally abrupt in onset, and follows a fulminate course with high rates of hospitalization, ICT admission, respiratory failure, and requirement for intubation. Mortality is generally high, especially if mechanical ventilation is required. Non-invasive ventilatory support may be considered, although the rapid progression to respiratory failure often necessitates intubation at the time of presentation. Bronchoscopy is often required to establish the diagnosis, and empirical antimicrobial treatment specifically targeted to P. carinii should be initiated while awaiting confirmation. Adjunctive corticosteroids may accelerate recovery, although their use has not yet been established in non-HIV PCP. For the ICU physicians to diagnose PCP, the non-specific presentation of an acute febrile illness and respiratory distress with diffuse pulmonary infiltrates requires a high clinical index of suspician, familiarity with clinical conditions associated with increased risk for PCP, and a low threshold for bronchoscopy to establish the diagnosis.

Pulmonary infections in the HIV-infected patient in the era of highly active antiretroviral therapy: an update

The highly active antiretroviral therapy (HAART) era began in 1996 when the combination of multiple antiretroviral agents was found to improve outcomes in HIV-infected patients. HAART has made a tremendous impact on the progression of HIV and on the morbidity and mortality associated with its opportunistic infections. HIV-positive patients who respond to HAART have a decreased incidence of opportunistic infections. Studies have documented close to a 50% decline in the incidence of pneumocystis pneumonia and bacterial pneumonia with the use of antiretroviral therapy. Primary and secondary prophylaxis for pneumocystis pneumonia can be discontinued in patients who show a sustained response to antiretroviral therapy. Unique to the HAART era, immune reconstitution syndrome is characterized by a paradoxical deterioration of a preexisting infection that is temporally related to the recovery of the immune system. Recently, more and more patients are being admitted for non-AIDS related illnesses in the HAART era.

Management of Chronic Hepatitis C in Patients Co-Infected with HIV

Hepatitis C virus (HCV) infection is a significant public health problem and one of the most important causes of chronic liver disease worldwide. Co-infection with HCV and HIV occurs frequently, mainly because both viruses share the same transmission routes. In recent years, the life expectancy of patients with HIV disease has been increased due to the introduction of highly active antiretroviral therapy (HAART). Furthermore, several studies have established that HIV infection is associated with a major progression of the HCV-related liver disease. Thus, end-stage liver disease has become a leading cause of morbidity and mortality in this population, emphasising the importance of treatment of chronic hepatitis C in HIV-infected persons. The biological and histological benefit of interferon-alpha (IFNalpha) therapy in patients co-infected with HCV/HIV is not significantly different from that noted in similar patients without HIV when the HIV infection is adequately controlled. However, patients with low CD4+ cell counts tend to respond poorly to anti-HCV therapy.Given the relatively low sustained virological response rate to IFN alone, the use of IFNalpha monotherapy has been largely abandoned in favour of combination therapy with ribavirin. In the last 2 years, IFN plus ribavirin combination therapy has been the standard care for the treatment of chronic hepatitis C. Although information on the safety and efficacy of this dual therapy in HCV/HIV co-infected patients is scarce, recent trials have reported that the combination of IFN plus ribavirin is well tolerated and feasible in patients co-infected with HCV/HIV. However, the rates of sustained virological response seem to be worse than those observed in patients without HIV infection. New IFN formulations (e.g. pegylated interferon) plus ribavirin appear to be way of the future for the treatment of chronic hepatitis C in patients both with and without HIV co-infection.

Use of filgrastim as adjuvant therapy in patients with AIDS-related cytomegalovirus retinitis

BACKGROUND

Neutropenia in AIDS predisposes to bacterial infection. Granulocyte colony-stimulating factor (filgrastim) can reverse neutropenia.

OBJECTIVE

To determine the effects of filgrastim on bacterial infections, hospitalization, and mortality in patients with cytomegalovirus retinitis and AIDS.

METHODS

Using a person-time analysis, a retrospective cohort study of filgrastim adjuvant therapy in three multicenter clinical trials of anti-cytomegalovirus therapy during the period 1990-1997 measured filgrastim use, bacterial infections, and mortality.

RESULTS

Of 719 patients, 379 patients used filgrastim for 31% of the follow-up time. There was an inverse relationship between the 389 confirmed bacterial infections, including 186 bacteremias, and absolute neutrophil counts. Before adjustment for CD4 T-cells counts and antibiotic/antiretroviral therapy, filgrastim was associated with reduced risk of catheter-related bacteremia [relative risk (RR), 0.52; P = 0.02] and repeat bacterial infection (RR, 0.41; P = < 0.01). After adjustment, the RR of catheter-related bacteremia with filgrastim use was decreased (RRadj, 0.69; P = 0.16) and the RR of repeat bacterial infection with filgrastim use was of marginal significance (RRadj, 0.57; P = 0.07), possibly due to the confounding effect of trimethoprim-sulfamethoxazole on all bacteremia (RRadj, 0.55; P = < 0.01). Unrelated to bacteremia, filgrastim use was associated with a 56% reduction in mortality (P < 0.01).

CONCLUSIONS

There was a large survival benefit associated with filgrastim use in this study but the reasons for this benefit are unclear. Although a reduction in crude risk of some bacterial infections with filgrastim use was detected, after adjustment for potentially confounding factors these risks were smaller and no longer statistically significant.

Hepatitis C in HIV-infected patients--therapeutic approach

The use of highly active antiretroviral therapy (HAART) has extended the lifespan of patients infected with human immunodeficiency virus (HIV). As the prognosis of HIV infection has improved, liver disease associated with hepatitis C virus (HCV) has become clinically significant in patients with HIV, liver failure being a frequent cause of death in this population. HIV infection may accelerate the course of liver disease in patients co-infected with HCV, so infection with HCV should be treated like any other opportunistic disease in these patients. Nowadays, combination therapy with interferon-alpha and ribavirin is the standard treatment for chronic hepatitis C in HIV-negative patients. Preliminary results of combination therapy in HIV/HCV co-infected patients have been promising, showing a sustained response rate in 40% of these patients. Patients with higher CD4 counts and lower HCV/HIV viral load and those infected with HCV genotype 3a have a better response to therapy. Potential drug interactions between HAART therapy and interferon and ribavirin treatment emphasize the importance of initiating treatment of HCV infection in HIV-positive individuals as soon as possible and ideally before the need for anti-HIV therapy. Recent case reports have suggested that liver transplantation might be an appropriate procedure in HIV patients with undetectable HIV viral load, high CD4 counts and HCV advanced liver disease. However, the limited amount of available information and the complexities of drug interactions between HAART therapy and immunosuppressive drugs oblige us to be prudent within considering such a procedure.

Effect of post-treatment isoniazid on prevention of recurrent tuberculosis in HIV-1-infected individuals: a randomised trial

BACKGROUND

Patients with HIV-1 infection respond well to treatment for active tuberculosis, but whether such patients are at increased risk of disease recurrence after complete cure is uncertain. We did a randomised trial in Port au Prince, Haiti, to determine whether recurrent tuberculosis after curative tuberculosis treatment is more common in HIV-1-infected individuals than HIV-1-uninfected individuals, and to determine whether post-treatment isoniazid prophylaxis decreases the risk of recurrent tuberculosis.

METHODS

Patients older than 18 years who were diagnosed with a first episode of tuberculosis at the national HIV testing centre in Haiti, and who successfully completed a 6-month rifampicin-containing regimen for active pulmonary tuberculosis, were randomly assigned 1 year of post-treatment isoniazid prophylaxis or placebo. The primary outcome measure was rate of recurrent tuberculosis after at least 24 months. An intention-to-treat analysis was used.

FINDINGS

Of 354 patients with active pulmonary tuberculosis, 274 successfully completed treatment, and 233 were randomised. Of 142 HIV-1-positive patients, 68 were assigned isoniazid and 74 placebo. Of 91 HIV-1-negative individuals, 51 were assigned isoniazid and 40 placebo. The rate of recurrent tuberculosis was 4.8 per 100 person-years in HIV-1-infected individuals and 0.4 per 100 person-years in uninfected individuals (relative risk 10.7 [95% CI 1.4-81.6]). Among HIV-1-positive patients receiving isoniazid, the tuberculosis recurrence rate was 1.4 per 100 person-years, and among HIV-1-positive patients receiving placebo, it was 7.8 per 100 person-years (0.18 [0.04-0.83]). Among HIV-1-positive individuals, all cases of recurrent tuberculosis occurred in individuals with a history of HIV-1-related symptoms before initial tuberculosis diagnosis.

INTERPRETATION

The rate of recurrent tuberculosis is higher in HIV-1-positive individuals than in HIV-1-negative individuals, and is strongly associated with a history of symptomatic HIV-1 disease before initial tuberculosis diagnosis. Post-treatment isoniazid prophylaxis decreases the risk of recurrence in HIV-1-positive individuals, and should be considered for HIV-1-positive individuals with a history of HIV-1-related symptoms at the time of tuberculosis diagnosis.

Anti-toxoplasma activities of antiretroviral drugs and interactions with pyrimethamine and sulfadiazine in vitro

The anti-Toxoplasma activities of nine antiretroviral drugs were examined in vitro. Nucleoside analogs had no effect on parasite growth, whereas ritonavir and nelfinavir were inhibitory for Toxoplasma, with 50% inhibitory concentrations of 5.4 and 4.0 microg/ml, respectively. None of the antiviral drugs affected the anti-Toxoplasma activity of pyrimethamine or sulfadiazine.

Hepatitis C virus/human immunodeficiency virus coinfection: clinical management issues

The use of highly active antiretroviral therapy (HAART) has extended the healthy lifespan of patients infected with human immunodeficiency virus (HIV); deaths among people with AIDS declined for the first time in 1996, after the institution of this therapeutic approach. As the life expectancy of HIV-infected patients increases, greater attention will need to be focused on the recognition and management of potentially severe concurrent illnesses that may increase their mid- to long-range morbidity and mortality. The incidence of infection by hepatitis C virus (HCV) is increased among patients with HIV disease, reflecting shared epidemiological risks. HCV not only may have an impact on the health status of HIV-infected patients but also may decrease their quality of life and increase their health care costs. Although clinicians have been reluctant to treat viral hepatitis C in the HIV-infected population, this therapeutic nihilism is unwarranted. The majority of studies have concluded that treatment of hepatitis C in HIV-infected patients results in an initial efficacy and long-term response similar to those in the HIV-seronegative population. Furthermore, treatment of HCV infection in HCV/HIV-coinfected patients may improve tolerance for antiretroviral medications. Physicians caring for patients with HIV infection require up-to-date information to make rational decisions regarding HCV coinfection to ensure that morbidity and mortality are minimized and that quality of life and medical care costs are optimized.

Cotrimoxazole for prenatal treatment of congenital toxoplasmosis?

Congenital toxoplasmosis is still one of the most frequent causes of fetal death. Despite a significant improvement in diagnosis, particularly in utero diagnosis, maternal treatment is only partially effective in preventing transmission to the fetus and treating fetal infection. Maternal treatment is based on drugs developed 50 years ago, which may have limited efficacy (spiramycin) or serious side-effects (pyrimethamine). Data on the use of cotrimoxazole in mouse models of toxoplasmosis and for preventing toxoplasmic encephalitis in patients suffering from AIDS have led Francis Derouin and colleagues to consider the potential of cotrimoxazole for prenatal prevention and treatment of toxoplasmic fetal death.