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Giovanni Rezza

Publications and source records attributed to Giovanni Rezza.

60 records · Page 4Linked to original sources
PubMed2002

Precision and accuracy of a procedure for detecting recent human immunodeficiency virus infections by calculating the antibody avidity index by an automated immunoassay-based method.

We evaluated the precision and accuracy of a procedure for detecting recent human immunodeficiency virus (HIV) infections, specifically, the avidity index (AI) calculated using a method based on an automated AxSYM HIV 1/2gO assay (Abbott). To evaluate precision, we performed multiple replicates on eight HIV-positive serum samples. To evaluate the accuracy in identifying recent infections (i.e., within 6 months of seroconversion), we used 216 serum samples from 47 persons whose dates of seroconversion were known. To evaluate the sensitivity and specificity of the procedure for different AI cutoff values, we performed receiver operating characteristic (ROC) analysis. To determine the effects of antiretroviral treatment, advanced stage of the disease (i.e., low CD4-cell count), and low HIV viral load on the AI, we analyzed 15 serum samples from 15 persons whose dates of seroconversion were unknown. The precision study showed that the procedure was robust (i.e., the total variance of the AI was lower than 10%). Regarding accuracy, the mean AI was significantly lower for samples collected within 6 months of seroconversion, compared to those collected afterwards (0.68 +/- 0.16 versus 0.99 +/- 0.10; P < 0.0001), with no overlap of the 95% confidence intervals. The ROC analysis revealed that an AI lower than 0.6 had a sensitivity of 33.3% and a specificity of 98.4%, compared to 87.9 and 86.3%, respectively, for an AI lower than 0.9. Antiretroviral treatment, low CD4-cell count, and low viral load had no apparent effect on the AI. In conclusion, this procedure is reproducible and accurate in identifying recent infections; it is automated, inexpensive, and easy to perform, and it provides a quantitative result with different levels of sensitivity and specificity depending on the selected cutoff.

AIDS Serodiagnosis↗
PubMed2002

No protective effect of acyclovir on HIV disease progression in a cohort of HSV-2-HIV-infected individuals.

The efficacy of anti-herpetic drugs in decreasing HIV disease progression has not been clarified. We studied a cohort of 126 HIV-positive individuals with known date of seroconversion who were HSV-2-seropositive to determine if progression to AIDS was influenced by treatment with acyclovir. In the multivariate analysis, being homosexual and low CD4 count were associated with a faster progression to AIDS, whereas treatment with acyclovir showed a 37.0% protective effect compared to those who did not receive it when antiretroviral treatment was not included in the model. When including antiretroviral therapy, the protective effect of acyclovir decreased to 9.0% and that of antiretroviral therapy was 43.0% for monotherapy and 36.0% for double therapy, suggesting that most of the protective effect of acyclovir in the previous model was due to antiretroviral therapy. In conclusion, treatment with acyclovir does not seem to prolong significantly survival to AIDS among HIV-positive individuals who are HSV-2-infected.

Acyclovir↗
PubMed2002

[Infections and other causes of mortality correlated with drug addiction].

Drug use and related injection practices determine an excess mortality in drug abusers compared to the general population adjusted for age and gender. HIV/AIDS and overdose are the most important causes of death among injecting drug users; however, excess mortality is also due to other causes, such as cirrhosis and endocarditis. Infections have a great impact on the health of injection drug users. Viral infections, such as HIV, HCV, and HBV, are the most important ones, but bacterial and fungal infections, and, to a lesser extent, protozoal infections, are also common. In depth knowledge of drug-related morbidity and mortality causes is important to improve clinical skills and to implement control activities.

Cause of Death↗
PubMedDate not supplied

[Epidemiology of HIV infection in Italy].

AIDS surveillance systems, which have provided for many years useful information on HIV epidemic dynamics, are no longer useful for estimating the evolution of the HIV epidemic due to the effect of anti-retroviral treatments that have strongly improved survival of HIV-infected persons. To obtain reliable data on the HIV epidemic, some Italian provinces and regions (Lazio, Veneto, Friuli Venezia-Giulia, Trento, Modena) have set up local surveillance systems of the new HIV diagnoses. Aggregated data collected by these systems since 1988, show that the rapid spread of the infection in the eighties has been followed by a progressive decrease in the number of new diagnoses during the nineties; in more recent years this trend has levelled-off. The composition of cases by exposure category has greatly changed over time: in 1988 75.2% of cases were injecting drug users, whereas in 2000 58.5% of cases acquired the infection through sexual contacts. HIV incidence for the considered areas decreased from 19.2 per 100.000 inhabitants in 1992, to 6.7 per 100.000 inhabitants in 2000. Median age at diagnosis increased over time, from 27 years in 1988 to 34 years in 2000. The changed pattern of the HIV epidemic in Italy stresses the need of a nation-wide surveillance system for HIV infections aimed at allocation of adequate economic resources and planning specific prevention programmes.

Adult↗
PubMedDate not supplied

[Survival, progression to AIDS and immunosuppression in HIV-positive individuals before and after the introduction of the highly active antiretroviral therapy (HAART)].

We evaluated the changes in the progression to death and AIDS and in the mean level of CD4 lymphocytes by calendar period in HIV-positive individuals before and after the introduction of HAART. Through data collected in a prospective cohort study (Italian Seroconversion Study) of 1899 HIV-infected persons with well estimated date of seroconversion, considered as time-zero of analysis, we calculated Kaplan-Meier curves and Cox models, allowing for staggered entries, to estimate the cumulative probability of survival and hazard-ratios (HR) for death and for AIDS by calendar period (1980-1996: pre-HAART era, 1997-1998: first HAART era, and 1999-2001: second HAART era), age at seroconversion, gender, and exposure category. During 17251 person-years, 660 HIV-positive patients developed AIDS and 510 died. Before 1997, the cumulative probability of survival, at twelve years from seroconversion, was 51.0%. In the period 1997-1998 the probability was 77.3% and in the period 1999-2001 it further increased at 91.2%. In the period 1980-1996 only older age at seroconversion was associated with more rapid progression to death. In the period 1987-2001 individuals infected through injecting drug use had a reduced increase of survival compared to those infected through sexual contact. Similar results were obtained for progression to AIDS. Finally we estimated an improved level of immunesuppression in the period 1987-2001. In fact, while in the period 1980-1996 we estimated a decrease of the CD4 lymphocites of -54.8 cells/mm3 (95% CI: -52.0; -57.6) per year; after 1996, we estimated an increase of CD4 of +39.6 (95% CI +34.1; +45.1)per year. This study provides strong evidence that the efficacy of the HAART estimated in the controlled clinical trials has resulted in a real reduction at the population level of morbidity and mortality.

Acquired Immunodeficiency Syndrome↗