Search PubMed⌕ Search

Biomedical subjects

C Leport

Publications and source records attributed to C Leport.

At least 73 records · Page 4Linked to original sources
PubMed1998

Intention-to-treat vs. on-treatment analyses of clinical trial data: experience from a study of pyrimethamine in the primary prophylaxis of toxoplasmosis in HIV-infected patients. ANRS 005/ACTG 154 Trial Group.

Randomized clinical trials analyzed by the intent-to-treat approach provide unbiased comparisons among treatment groups. To avoid dilution of treatment effect, many people also perform an analysis by treatment actually received, although this method may introduce bias into the results. This paper presents several approaches used for analyzing data of a recent trial and the difficulties encountered in interpreting the results of each approach. The ANRS 005/ACTG 154 Study was a double-blind, placebo-controlled, randomized, international (French, U.S., and Spanish) multicenter trial designed to assess the effectiveness of pyrimethamine for the primary prophylaxis of cerebral toxoplasmosis (CT) in HIV-infected patients with advanced immunodeficiency. In the intention-to-treat analysis, the cumulative probability of CT at 1 year did not differ significantly between the pyrimethamine arm (11.9%) and the placebo arm (13.1%), Hazard Ratio (HR) = 0.94 (95% Confidence Interval (CI) = 0.62-1.42), whereas an on-treatment analysis resulted in a significant difference: 4.2% in the pyrimethamine arm and 12.4% in the placebo arm, HR = 0.44 (95% CI = 0.24-0.80). The data showed a significant interaction between compliance and treatment outcome; and side effects were more frequently cited as reasons for compliance violations in the pyrimethamine group. Several different analytic approaches (censoring data at the time patients discontinued the study medication only for selected reasons) failed to explain the disparity between the estimation of effect of pyrimethamine by the intention-to-treat and on-treatment analyses. This experience led us to believe that comparing the results of both analyses was the best method to convince clinicians that intention-to-treat was the only interpretable analysis. We were concerned that even if pyrimethamine had a beneficial effect, it was very difficult (1) to quantify and (2) to apply to clinical practice unless one could predict the occurrence of study drug discontinuation for each patient at the time of treatment assignment. Although exploratory analyses may yield clinically relevant information and useful clarifications in the evaluation of treatments, intention-to-treat remains the only interpretable analysis of clinical trials.

AIDS-Related Opportunistic Infections↗
PubMed1998

[Cerebral toxoplasmosis in HIV infected patients intolerant of cotrimoxazole].

Using results of a multicentric randomized prospective trial of primary prophylaxis of Pneumocystis carinii pneumonia in HIV-infected patients which compared sulfamethoxazole-trimethoprim and pentamidine isethionate, the risk to develop cerebral toxoplasmosis was analyzed in the two assigned groups and in the groups of patients who stopped sulfamethoxazole-trimethoprim prophylaxis. The risk to develop cerebral toxoplasmosis appeared significantly higher in the group of patients who stopped sulfamethoxazole-trimethoprim consecutively to cutaneous hypersensitivity.

AIDS-Related Opportunistic Infections↗
PubMed1997

Survival after AIDS-defining events in patients with < 200 lymphocytes CD4+ x 10(6)/L who are toxoplasmosis antibody positive. ANRS 005/ACTG 154 Trial Group.

The objective of this study was to assess whether patients with CD4+ cell counts <200 x 10(6)/L have a decreased survival after the occurrence of any AIDS-defining event; 187 patients from the placebo arm of a clinical trial of toxoplasmosis prophylaxis (ANRS005-ACTG154) were included. For this analysis, patients were HIV infected without any AIDS-defining event, had a CD4+ lymphocyte count < 200 x 10(6)/L, had a positive serology for Toxoplasma gondii, and had no severe liver, renal, or hematologic abnormalities. We used proportional hazards regression to study the relationships between baseline variables. AIDS-defining events as time-dependent variables, and survival. The risk of dying was increased by 1.9 for a 10-year increase in age and by 1.3 when CD4+ decreased by 50 x 10(6)/L; after the occurrence of a pneumocystosis, a cytomegalovirus infection, or a toxoplasmosis, the risk of dying was multiplied, respectively, by 10.9 (3.0-40.2), 10.0 (2.8-35.4), and 10.0 (4.5-22.2). None of the other AIDS-defining events was associated with an increased risk of dying, but the power to detect such an association was limited. We conclude that the occurrence of pneumocystosis, cytomegalovirus infection, or toxoplasmosis; age; and CD4+ cell count are important determinants of survival for HIV1-infected patients with CD4+ counts < 200 x 10(6)/L who are toxoplasmosis antibody positive.

AIDS-Related Opportunistic Infections↗
PubMed1997

Low prevalence of active parvovirus B19 infection in HIV-infected patients.

In a prospective study to determine the prevalence of parvovirus B19 in adult patients positive for the human immunodeficiency virus, a series of 55 consecutively presenting patients was tested for antibodies to parvovirus B19 and parvovirus B19 DNA. Specific IgG antibodies were detected in 96% of cases; specific IgM antibodies were present in 10%. Viral DNA was not detected in any of the sera analysed by polymerase chain reaction. Anemia could not be correlated with the presence of either IgG or IgM antibodies to parvovirus B19. Thus, no evidence of acute or chronic parvovirus B19 infection was found in the 55 patients. These findings suggest that active parvovirus B19 infection is uncommon in HIV-infected patients.

AIDS-Related Opportunistic Infections↗
PubMed1997

Increased risk of toxoplasmic encephalitis in human immunodeficiency virus-infected patients with pyrimethamine-related rash. ANRS 005-ACTG 154 Trial Group. Agence Nationale de Recherche sur le SIDA (ANRS-INSERM) and the NIAID-AIDS Clinical Trials Group.

Although drug-induced rash is frequent in human immunodeficiency virus (HIV)-infected patients, rash due to pyrimethamine has not been described previously. In a randomized, double-blind, placebo-controlled study of pyrimethamine as primary prophylaxis for toxoplasmic encephalitis, the incidence of rash (per hundred patient-years) was 8.1 in the pyrimethamine group versus 1.5 in the placebo group (P < .0002). The 1-year incidence of toxoplasmic encephalitis after occurrence of rash was 37%, as compared with 9.6% in the pyrimethamine group without rash, with a 3.7 times higher risk for patients with pyrimethamine-induced rash (P = .001); the incidence was 13% in the placebo group. At the time of toxoplasmic encephalitis, pyrimethamine was successfully readministered to 80% of patients who discontinued it because of rash. Thus, pyrimethamine, when used for prophylaxis, does induce rash in HIV-infected patients. These patients are at higher risk for toxoplasmic encephalitis and should be carefully monitored for it.

AIDS-Related Opportunistic Infections↗
PubMed1997

Cytomegalovirus (CMV) viremia and the CD4+ lymphocyte count as predictors of CMV disease in patients infected with human immunodeficiency virus.

We screened 192 patients infected with human immunodeficiency virus (HIV) to examine the relation between CD4+ lymphocyte counts and cytomegalovirus (CMV) viremia and the occurrence of CMV disease and subsequent duration of survival. When we stratified the viremic patients by CD4+ lymphocyte counts, the proportions were as follows: <50/mm3, 20 (25%) of 80 patients; 50-100/mm3, 2 (5.5%) of 36; 101-150/mm3, none of 14; and >150/mm3, 1 (1.5%) of 62. After a mean follow-up period of 8.5 months, 21 (11%) of 192 patients developed CMV disease. The probability of developing CMV disease at 6 months was 13% when the CD4+ lymphocyte count was <50/mm3, 3% when the CD4+ lymphocyte count was 50-100/mm3, and 0 when the CD4+ lymphocyte count was >100/mm3; this probability was 46% for viremic patients and 1% for nonviremic patients. In a multivariate analysis, CMV viremia was independently prognostic of CMV disease (relative risk, 22.03; 95% confidence interval, 6.49-78.97; P < .001), whereas a CD4+ lymphocyte count of <50/mm3 was not (P = .26). These results support the value of CMV viremia for predicting which HIV-infected patients are at risk of developing CMV disease and should therefore receive primary prophylaxis.

AIDS-Related Opportunistic Infections↗
PubMed1997

A prospective study of criteria for the diagnosis of toxoplasmic encephalitis in 186 AIDS patients. The BIOTOXO Study Group.

OBJECTIVE: To define the factors associated with diagnosis of toxoplasmic encephalitis (TE) in AIDS patients; and to establish a rational procedure for the clinician faced with a decision concerning empiric antitoxoplasma therapy. DESIGN: A 15-month prospective multicentre cohort study in France. METHODS: One hundred and eighty-six consecutive HIV-positive inpatients undergoing empiric antitoxoplasma therapy for a first episode of presumed TE were monitored. The clinician's initial estimation of the probability of response to antitoxoplasma therapy was recorded. In addition, a validation committee classified cases as TE or non-TE. RESULTS: Among the 186 patients, the following variables were significantly more frequent in TE (n = 113) than non-TE (n = 73) patients: fever (59% versus 40%). headache (55% versus 33%), seizures (22% versus 11%), suggestive lesions on the brain scan (98% versus 76%), positive Toxoplasma serology (97% versus 71%). Median CD4+ lymphocyte count was significantly higher in TE than in non-TE (27 x 10(6)/l versus 11 x 10(6)/l). The rate of TE in patients on systemic antiprotozoal prophylaxis at entry was 43% as compared with 75% in patients without previous prophylaxis. Pre-therapy estimation of response to empiric therapy was highly correlated with final diagnosis. Multivariate logistic regression analysis showed that the following variables contributed independently to the diagnosis of TE: clinician's estimation of response to treatment at entry > 75%; absence of systemic antiprotozoal prophylaxis; seizures; headache; suggestive lesions on CT or MRI brain scan; and positive Toxoplasma serology. CONCLUSIONS: A linear logistic model is proposed which uses significant variables, which are readily available. This model gives good accuracy to classify suspected cases of TE.

AIDS-Related Opportunistic Infections↗
PubMed1997

Potential efficacy of fumagillin in intestinal microsporidiosis due to Enterocytozoon bieneusi in patients with HIV infection: results of a drug screening study. The French Microsporidiosis Study Group.

OBJECTIVE: Intestinal microsporidiosis due to Enterocytozoon bieneusi is a frequent cause of chronic diarrhoea in patients with HIV infection for which there is no available therapy. This study was designed to search for a drug with activity against this organism. DESIGN: Prospective open-labelled Phase II multicentre study. SETTING: University hospitals. PATIENTS: Sixty HIV-infected men with intestinal E. bieneusi infection. INTERVENTIONS: Ten drug regimens were consecutively tested orally for 3 weeks: albendazole plus metronidazole, sulphadiazine plus pyrimethamine, atovaquone, doxycycline plus nifuroxazide, itraconazole, flubendazole, chloroquine, paromomycin, sparfloxacin and fumagillin. Nine evaluable patients per regimen were required, but each patient could be enrolled up to three times in the study. OUTCOME MEASURE: Efficacy was assessed primarily by the clearance of E. bieneusi from stools and intestinal biopsies. The safety of each regimen was also assessed. RESULTS: Only purified fumagillin was able to clear E. bieneusi from stools as well as intestinal biopsies, whereas all other regimens failed to show antiparasitic efficacy. However, only four patients received fumagillin because of drug-induced thrombocytopenia. The four patients who received fumagillin remained free of E. bieneusi infection after a mean follow-up of 10 months. CONCLUSION: Eradication of E. bieneusi from the intestinal tract of patients with HIV infection and persistent immunosuppression is an achievable goal. Our study allowed the identification of oral fumagillin as a potential treatment for intestinal microsporidiosis due to E. bieneusi.

AIDS-Related Opportunistic Infections↗
PubMed1997

[Prevention of toxoplasmosis in immunocompromised patients].

The main underlying immunosuppressive conditions requiring prevention of toxoplasmosis are organ transplantations (especially heart and bone marrow transplants) and advanced HIV infection (CD4 + lymphocytes count < 100/mm3). Preventive strategies consist in reducing the rate of primary infection, mainly through hygiene and diet measures, and introducing chemoprophylaxis in patients already contaminated by the parasite: the most precise knowledge in this field concerns HIV infected patients. For prevention of recurrence, patients should receive pyrimethamine-sulfadiazine, or otherwise pyrimethamine-clindamycin combinations. For primary prophylaxis, cotrimoxazole is the first-line therapy. If patients cannot tolerate cotrimoxazole, a regiment including dapsone plus pyrimethamine is a possible alternative; pyrimethamine alone and atovaquone are currently under investigation.

AIDS-Related Opportunistic Infections↗
PubMed1996

[Prophylaxis of infectious endocarditis].

Prophylaxis of infective endocarditis has been the subject of recommendations from most countries for several years. The basis of the recommendations is the administration of prophylactic antibiotics preceding a procedure at risk for patients with a known at risk cardiac disease. The antimicrobial agent is selected to be active against the main microorganisms causing bacteremia according to the type of at risk procedure. Furthermore, the choice and modalities of antibiotic prophylaxis are adapted to take into account a possible documented allergy to penicillin, the type of predisposing cardiac disease, the number of performed procedures and the requirement for general anesthesia. Future advances should concern the diffusion and application of these recommendations, and the appropriateness of these practices in terms of general cost benefit assessment.

Antibiotic Prophylaxis↗