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G Ippolito

Publications and source records attributed to G Ippolito.

At least 73 records · Page 4Linked to original sources
PubMed2001

Clinical manifestation of HIV-related pulmonary hypertension.

In recent years, much more thought has been given to the pathogenic role of HIV and to the clinical manifestations of HIV-related pulmonary hypertension (HRPH), which currently represents one of the most severe events during HIV disease. HRPH occurs in early and late stages of HIV infection and does not seem to be related to the degree of immune deficiency. Many of the symptoms in HRPH result from right ventricular dysfunction: the first clinical manifestation is effort intolerance and exertional dyspnea that will progress to the point of breathlessness at rest. The diagnosis of HRPH can be made only after all etiologies for pulmonary hypertension have been excluded. Echocardiography has been proven to be an extremely useful tool for diagnosing HRPH, and Doppler echocardiography can be used to estimate systolic pulmonary artery pressure and to monitor the effects of therapy. Assessment of hemodynamic measures by catheterization remains, however, the best test for evaluating response to therapy. Cardiac catheterization is mandatory to characterize the disease and exclude an underlying cardiac shunt as etiology. Vasodilators have been extensively used in the treatment of pulmonary hypertension, since vasoconstriction is a determinant characteristic of this disease. However, HRPH remains a progressive disease for which treatment is often unsatisfactory and there is no cure. As new, more efficient antiretroviral treatment are introduced, clinicians should expect to encounter an increasing number of cases of pulmonary hypertension in HIV+ patients in the future.

HIV Infections↗
PubMed2001

Catheter-related bloodstream infections in HIV-infected patients.

Bloodstream infections (BSI) constitute a significant public health problem and represent an important cause of morbidity and mortality in hospitalized patients, with an approximate incidence of one episode per hundred hospital admissions. Studies on BSI in HIV+ patients have identified central venous catheters (CVC) as a risk factor, with an attributable mortality rate of 10-20%. The long-term CVC-related infection risk appeared to be 5 to 10-fold higher with respect to the infection rates among HIV- patients. CVC associated infection rate ranges from 1.3 to 12 infections per 1,000 catheter-days. Staphylococcus aureus is the most common etiologic agent causative of CVC-related BSI, likely the result of the high skin and nasal carriage of this organism among HIV+ patients, mostly intravenous drug users. Coagulase-negative staphylococci are also frequently identified as cause of CVC-related BSI, likely the result of breaches in infection control measures and in antiseptic technique during CVC management. Treating bacteremia without catheter removal would be optimal, but the reported efficacy of systemic antibiotic therapy alone is only 25-32%. Conversely, recent studies have shown that, using an antibiotic-lock procedure, up to 90% of HIV-infected and uninfected patients achieved complete eradication of catheter-related BSIs without catheter removal. Clinical trials using new materials such as covalently linked heparin on the CVC surface, electrically charged CVC, novel topical agents that interfere with bacterial colonization, antiadhesin molecules and agents that block the gene expression involved in the biofilm formation, are all needed to reduce the high catheter-related infection risk among HIV+ patients.

Blood-Borne Pathogens↗
PubMed2001

Risk of HIV and other blood-borne infections in the cardiac setting: patient-to-provider and provider-to-patient transmission.

Health care workers (HCWs) face a well-recognized risk of acquiring blood-borne pathogens in their workplace, in particular hepatitis B and C viruses (HBV/HBC) and human immunodeficiency virus (HIV). Additionally, infected HCWs performing invasive exposure-prone procedures, including in the cardiac setting, represent a potential risk for patients. An increasing number of infected persons could need specific cardiac diagnostic procedures and surgical treatment in the future, regardless of their sex or age. The risk of acquiring HIV, HCV, HBV infection after a single at-risk exposure averages 0.5%, and 1-2%, and 4-30%, respectively. The frequency of percutaneous exposure ranges from 1 to 15 per 100 surgical interventions, with cardiothoracic surgery reporting the highest rates of exposures; mucocutaneous contamination by blood-splash occurs in 50% of cardiothoracic operations. In the Italian Surveillance (SIROH), a total of 987 percutaneous and 255 mucocutaneous exposures were reported in the cardiac setting; most occurred in cardiology units (46%), and in cardiovascular surgery (44%). Overall, 257 source patients were anti-HCV+, 54 HBsAg+, and 14 HIV+. No seroconversions were observed. In the literature, 14 outbreaks were reported documenting transmission of HBV from 12 infected HCWs to 107 patients, and 2 cases of HCV to 6 patients, during cardiothoracic surgery, especially related to sternotomy and its suturing. The transmission rate was estimated to be 5% to 13% for HBV, and 0.36% to 2.25% for HCV. Strategies in risk reduction include adequate surveillance, education, effective sharps disposal, personal protective equipment, safety devices, and innovative technology-based intraoperative procedures.

Blood-Borne Pathogens↗
PubMed2001

Transmission of hepatitis C virus in a gynecological surgery setting.

A cluster of hepatitis C virus (HCV) infections among gynecological patients who underwent surgical intervention in the same setting is described. An epidemiological investigation was conducted to identify the cases, the likely source of infection, and the route of transmission. Four recent HCV infections were identified. Based on molecular fingerprinting analysis and epidemiological investigation, transmission between the putative source patient (an HCV-positive woman who was the first patient of the surgical session) and outbreak patients was highly suggestive. All patients, including the source patient, were infected with HCV type 1b. Molecular characterization of HCV clones by sequence analysis of both structural envelope regions (20 clones from the source patient and 58 from the outbreak patients) and the nonstructural NS5 region of the viral genome (12 clones from the source patient and 32 from the outbreak patients) showed close homology between the viral isolates from the source and those from the outbreak patients that was higher than that observed between the viral isolates from the source and those from four unrelated, HCV type 1b-infected patients from the same geographical area (in the latter case, 33 clones were sequenced for the envelope regions and 30 were sequenced for the NS5 region). The mean percent divergence between clones was 4.69 for the envelope and 3.71 for the NS5 region in the source patient and the outbreak patients compared with 6.76 (P = 0.001) and 5.22 (P = 0.01) in the source patient and control patients, respectively. Among the risk factors investigated, only that of having undergone surgery in the morning session of the same day reached statistical significance (P = 0.003). The investigation showed that the source patient and outbreak patients shared only the administration of propofol in multidose vials. The study documents the risk of nosocomial transmission of HCV and the importance of infection control procedures in the operating room and highlights the crucial role of molecular strategies, especially sequence-based phylogenetic analysis of cloned viral isolates, in the investigation of HCV outbreaks.

Adult↗
PubMed2001

Sexual behaviour of heterosexual individuals with HIV infection naive for antiretroviral therapy in Italy.

BACKGROUND: Specific information about determinants of sexual behaviour of HIV infected heterosexuals, like injecting drug use (IDU), are essential to design interventions aimed at promoting safer sex practices. METHODS: We analysed data on sexual behaviour collected, between March 1997 and March 1999, through a self administered questionnaire among 1050 IDUs and 642 non-IDU heterosexuals enrolled in a prospective multicentre cohort study on the natural history of HIV infection. RESULTS: Among non-IDU heterosexuals, more women (48.5%) than men (25.1%) (p<0.001) reported that they were infected by HIV positive regular partners whose HIV status they were not aware of. Among the 1119 heterosexual males, one fifth reported having had more than 25 sexual partners during their lifetime. Condom use in the last sexual intercourse was more common among heterosexual IDUs (64.9%) than among non-IDU heterosexual males (58.3%) (p=0.05). Heterosexual IDU males were more likely (66.7%) than non-IDU heterosexuals (50.6%) to have an HIV negative partner (p<0.001). Of the 573 heterosexual females studied, 10.2% reported having had more than 25 lifetime sex partners. This proportion was higher among heterosexual IDUs (18.8%) than among non-IDU heterosexuals (4.3%) (p<0.001). Nearly 50% of the women in both groups reported having used a condom in the last intercourse. Almost 57% of heterosexual IDUs had a current HIV negative partner, compared with 34.9% non-IDU heterosexuals (p<0.001). In both sexes, the findings from univariate analysis were confirmed by multiple logistic regression analysis. CONCLUSIONS: This study identified some important differences, in both males and females, in sexual lifestyles according to injecting drug use (for example, in terms of HIV negative partners). This observation indicates the need to tailor HIV prevention messages according to history of injecting drug use.

Adult↗
PubMed2001

Guidelines of tuberculosis preventive therapy for HIV-infected persons: a prospective, multicentre study. GISTA (Gruppo Italiano di Studio Tubercolosi e AIDS).

The aim of this study was to assess the degree of implementation of national guidelines for isoniazid preventive therapy (IPT) among human immunodeficiency virus (HIV)-infected individuals and factors affecting the impact of the programme. Twenty-eight infectious disease hospital units in Italy participated in this observational, multicentre, prospective cohort study. A number of HIV-infected subjects, (n=1,705) seen for the first time as outpatients, were included in this analysis. Of the subjects considered, 1,215 out of the 1,705 completed purified protein derivative (PPD) screening. Variables independently associated with offering and completion of PPD screening included having acquired immune deficiency syndrome (AIDS), higher educational levels and currently receiving therapy. Overall, 103 subjects were identified as candidates for IPT. Of these subjects, five had tuberculosis and 15 had contraindications to IPT. Forty subjects agreed to start IPT, and 29 completed a full-course regimen. The incidence of tuberculosis among IPT candidates who either did not begin or discontinued IPT was 6.1 per 100 person-yrs, while no cases of tuberculosis were observed in subjects completing IPT. Several factors may limit the implementation of an isoniazid preventive therapy programme for human immunodeficiency virus-infected persons. Physicians fail to offer purified protein derivative screening to patients with high degrees of immunodeficiency, and those with a more intense workload seem to pay less attention to this test. The high number of contraindications among patients and their low level of acceptance further affects the impact of isoniazid preventive therapy.

AIDS-Related Opportunistic Infections↗
PubMed2001

Natural T cell immunity to intracellular pathogens and nonpeptidic immunoregulatory drugs.

Natural T (NT) lymphocytes recognize infected cells or microbial compounds without the classical genetic restriction of polymorphic major histocompatibility complex (MHC) molecules. This innate recognition pathway results in a broad and rapid antimicrobial response that may be critical for controlling the spread of intracellular pathogens, requiring the elimination of the infecting agent from both extracellular spaces and host cells. NT cells are mainly composed of alphabeta and gammadelta T lymphocytes that express natural killer (NK) receptors and recognize preferentially various nonpeptidic antigens. Similar to NK cells, NT lymphocytes can 'see' and kill target cells deficient in the expression of one or more MHC class I molecules. NT cells expressing the alphabeta TCR can recognize lipid and lipoglycan antigens presented in the context of nonpolymorphic CD1 molecules, whereas phosphocarbohydrates and akilamines induce constitutive responses in most Vgamma9Vdelta2 NT lymphocytes. The remaining fraction of gammadelta NT cells express the Vdelta1 chain associated with different Vgamma-chains and may directly recognize self-antigens such as MICA, MICB or CD1 molecules. It is possible that NT lymphocytes may play two opposite roles during intracellular infections. First, in the acute phase, they may be critical for the initiation of pathogen elimination. Second, in the chronic phase, NT cells may be dangerous, if their potential autoreactivity is not well controlled. It is conceivable that novel strategies of immune intervention against emerging and re-emerging intracellular pathogens, such as human immundeficiency virus (HIV), hepatitis-C virus (HCV) and Mycobacterium tuberculosis (MTB) may involve the control of NT cell activation/anergy by (nonpeptidic) immunoregulatory drugs.

Acquired Immunodeficiency Syndrome↗
PubMed2001

Vdelta1 T lymphocytes expressing a Th1 phenotype are the major gammadelta T cell subset infiltrating the liver of HCV-infected persons.

BACKGROUND: Hepatitis C infection induces an acute and chronic liver inflammation that may lead to cirrhosis, liver failure, or hepatocarcinoma. Since the role of alphabeta T lymphocytes in hepatitis C virus (HCV) immunopathology has been analyzed extensively, we investigated the distribution and functional activation of gammadelta T cell subsets in chronically HCV-infected patients. MATERIALS AND METHODS: Blood samples and liver biopsies from 35 patients with compensated chronic HCV infection were compared in terms of T cell subset distribution, expression of activation markers, gammadelta T cell receptor (TCR) repertoire, and pattern of cytokine production. Moreover, we analyzed whether these immunological parameters were associated with other clinical observations (plasma viremia, ALT levels, Ishak index). RESULTS: Differing from peripheral blood distribution, a specific compartmentalization of Vdelta1 T cells (p < 0.001) was observed in the liver of HCV patients. These cells represented a relevant fraction of intrahepatic T lymphocytes (1.8-8.7%) and expressed the memory/effector phenotype (CD62-L- CD45-RO+CD95+). This phenotype was consistent with selective homing upon antigen recognition. Mitogenic stimulation of Vdelta1 + T lymphocytes recruited in the liver revealed the T helper cell type 1 (Th1) pattern of cytokine secretion. Interestingly, the frequency of interferon-gamma (IFN-gamma)-producing Vdelta1 T cells was associated with an higher degree of liver necroinflammation, measured by the Ishak index. Finally, the T-cell repertoire analysis revealed the absence of Vgamma selection in the TCR repertoire of intrahepatic Vdelta1 T cells. CONCLUSIONS: gammadelta T cell distribution in the peripheral blood differs from the Vdelta1 T cell subset because it is policlonally activated and recruited in the liver of chronic HCV-infected patients. During HCV-infection, this T cell subset may release Th1 cytokines and contribute to the necroinflammatory liver disease.

Adult↗
PubMed2000

Impact of combination antiretroviral therapy on the risk of tuberculosis among persons with HIV infection.

OBJECTIVE: To assess the association between use of different antiretroviral regimens and incidence of tuberculosis among HIV-infected individuals. DESIGN: Observational, multicenter, prospective cohort study. SETTING AND PATIENTS: Twenty-eight infectious diseases hospital units in Italy. A total of 2160 HIV-infected persons were considered for enrolment in a study on the implementation of tuberculosis preventive therapy between 1 May 1995 and 30 April 1996. The 1360 subjects who completed tuberculin screening at base-line were included in this analysis. Information on the use of antiretroviral therapies over time was collected. The median duration of follow-up was 104 weeks and 997 subjects (73.3%) completed the study. MAIN OUTCOME MEASURE: Incidence of active tuberculosis according to different types of antiretroviral therapy. RESULTS: Eighteen cases of tuberculosis were observed with an overall incidence rate of 0.79 per 100 person-years of observation [95% confidence interval (CI), 0.51-1.31]. Tuberculin positivity and low CD4+ lymphocyte count were the only base-line variables independently associated with the risk of tuberculosis. During follow-up, 637 patients took double combination antiretroviral therapy and 387 took triple combination therapy. After adjusting for base-line characteristics of enrolled individuals, the relative hazard of tuberculosis was 0.16 (95% CI, 0.03-0.74) for double combination therapy and 0.08 (95% CI, 0.01-0.88) for triple combination therapy compared with no therapy or monotherapy. CONCLUSIONS: Combination antiretroviral therapy significantly reduced the risk of tuberculosis in HIV-infected persons. In industrialized countries, the widespread use of this treatment may determine a decrease in the incidence of HIV-associated tuberculosis, possibly contributing to a reduction in the overall incidence of tuberculosis.

Adolescent↗
PubMed2000

Plasma viral load concentrations in women and men from different exposure categories and with known duration of HIV infection. I.CO.N.A. Study Group.

CONTEXT: According to recent studies, women have lower plasma HIV RNA concentrations than men. However, these studies did not take into account the duration of HIV infection. OBJECTIVES: To analyze the relationship between viral load and gender among individuals with known date of seroconversion. SETTING: Sixty infectious disease clinics in Italy. DESIGN: Cross-sectional analysis of data collected at enrollment in a cohort study. PARTICIPANTS: Injecting drug users and heterosexual contacts naive to antiretroviral therapy at enrollment (245 men; 170 women). MAIN OUTCOME MEASURES: Plasma HIV RNA concentrations, measured using quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) or signal amplification b-DNA assays before antiretroviral therapy. RESULTS: Plasma HIV RNA concentrations were similar by age and exposure category (p =.80 and p =.39, respectively). Median viral load among women was roughly half that of men (p =.002). The association between viral load and gender remained significant after fitting a two-way analysis of variance (p =.03) and after adjusting for CD4 count, modality of HIV transmission, and age at enrollment in a regression model. Viral load was 0.27 log10 copies/ml (95% confidence interval, 0.05-0.40; p =.01) lower in women (i.e., 50% lower in the raw scale). CONCLUSIONS: Plasma HIV RNA concentrations were found to be lower among women, even when considering the duration of HIV infection. Compared with men, it is possible women should be given highly aggressive antiretroviral therapy at lower HIV-RNA concentrations.

Adolescent↗
PubMed2000

Increasing proportion of late diagnosis of HIV infection among patients with AIDS in Italy following introduction of combination antiretroviral therapy.

We analyzed trends over time and determinants of late diagnosis of HIV infection among people diagnosed with AIDS in 1986 to 1998 in a tertiary care center in Rome, Italy. Information on the date of a first HIV test was collected prospectively, in addition to data routinely collected for AIDS reporting. Patients with AIDS were defined as "late testers" if the time interval between first positive HIV test result and AIDS diagnosis was < or = 3 months. Overall, 503 people with AIDS of 1977 included in the analysis (25.4%) were late testers. the proportion of late testers decreased from 62.5% in 1986 to 16% in 1995. Thereafter, this proportion increased to 20.5% in 1996, 33.7% in 1997, and 36.6% in 1998. In multivariate analysis, the following variables were significantly associated with late testing: AIDS diagnosis in years 1986 to 1993 or 1997 to 1998 compared with 1995, male gender, age > or = 45 years, men who have sex with men, heterosexual contacts, or having unknown transmission mode compared with intravenous drug users, and being born outside Italy. Since 1996, the overall number of AIDS cases diagnosed at our center began to decrease whereas the number of late-testing AIDS patients did not decrease, resulting in an increasing proportion of late testers during the last 3 years of the study. This findings may reflect the effect of combination antiretroviral therapy in slowing progression to AIDS of HIV-infected persons aware of their status. A relevant number of people still discover their HIV infection late and may therefore miss treatment opportunities. New testing strategies are needed to reach more people who engage in high-risk behaviors, especially those at risk for sexual transmission, and those born outside Italy.

Acquired Immunodeficiency Syndrome↗
PubMed2000

Brief report: effect of antiretroviral agents on T-lymphocyte subset counts in healthy HIV-negative individuals. The Italian Registry on Antiretroviral Postexposure Prophylaxis.

To study the effect of antiretroviral agents on T-lymphocyte counts in HIV-negative individuals, total counts and CD4+ and CD8+ lymphocyte counts were measured in health care workers (HCW) who had been occupationally exposed to HIV who were untreated (164 HCW, group A), or had received antiretroviral postexposure prophylaxis (PEP). PEP included zidovudine (150 HCW, group B), zidovudine plus lamivudine (48 HCW, group C), or zidovudine, lamivudine, and indinavir (85 HCW, group D), at standard dosage for a mean of 30, 27, and 27 days of treatment, respectively. Lymphocyte values were collected after a mean of 44 days following exposure in group A, 48 days in group B, and 30 days both in groups C and D. Student's t-, nonparametric Mann-Whitney, and Kruskal-Wallis tests were used for statistical analysis. A slight increase in mean CD4 (range, 4.8%-6. 7%) and CD8 (range, 1.4%-9.3%) cells/mm3 was observed in each group. Gender, PEP duration, side effects, and follow-up time did not correlate with responses. Data did not vary using CD4 and CD8 percentages. These findings seem to reject any direct effects of antiretroviral agents, independent of retroviral inhibition, on proliferation and redistribution of T lymphocytes, as well as the hypothesized braking of lymphocyte apoptosis. The observed variations could reflect biologic variability.

Anti-HIV Agents↗
PubMed2000

Insights into the reasons for discontinuation of the first highly active antiretroviral therapy (HAART) regimen in a cohort of antiretroviral naïve patients. I.CO.N.A. Study Group. Italian Cohort of Antiretroviral-Naïve Patients.

OBJECTIVE: To evaluate the frequency of discontinuation of the first highly active antiretroviral regimen (HAART) and the factors predictive of discontinuing for toxicity and failure in a population-based cohort of HIV-positive individuals in Italy, naïve from antiretrovirals at enrolment. METHODS: The study population consisted of individuals who initiated HAART and had at least one follow-up visit. The primary end-points were discontinuation of any component of HAART for drug toxicity and discontinuation for failure. Survival analyses were performed to identify predictive factors for reaching the two end-points. RESULTS: Eight hundred and sixty-two individuals initiated HAART; in 727 of them (84.3%) this consisted of two nucleoside reverse transcriptase inhibitors (NRTI) and one protease inhibitor (PI). Over a median follow-up of 45 weeks, 312 patients (36.2%) discontinued therapy: 182 (21.1%) discontinued due to toxicity, 44 (5.1%) due to failure. The probability of discontinuing HAART at 1 year was 25.5% [95% confidence interval (CI), 21.9-28.9] due to toxicity and 7.6% (95% CI, 4.9-1 0.3) due to failure. Independent factors associated with discontinuation for toxicity were: gender [relative hazard (RH) = 0.51; 95% CI, 0.32-0.80 for men versus women], type of treatment (indinavir-containing regimens, RH = 1.94; 95% CI, 1.10-3.41 and ritonavir-containing regimens, RH = 3.83; 95% CI, 2.09-7.03 versus hard-gell saquinavir) and time spent on treatment (RH = 0.89; 95% CI, 0.80-0.98 for each additional month). Discontinuation due to failure was independently associated with the most recent HIV-RNA (RH = 3.20; 95% CI, 1.74-5.88 for log10 copies/ml higher), and with type of treatment (indinavir-containing regimens, RH = 0.21; 95% CI, 0.06-0.78 and ritonavir-containing regimens, RH = 0.23; 95% CI, 0.04-1.26 versus hard-gell saquinavir). CONCLUSIONS: If the current HAART regimen caused no toxicity, less than 10% of naïve patients discontinue their first HAART regimen because of failure after 1 year from starting therapy.

Adult↗
PubMed2000

Cancer risk among men with, or at risk of, HIV infection in southern Europe.

OBJECTIVE: To evaluate the cancer risk in southern European men with, or at risk of, HIV infection. DESIGN: An analysis of longitudinal data to assess time-dependent rare events. METHODS: Data from a cohort of HIV seroconverters, and from two hospital-based HIV seroprevalent cohorts were combined and analysed. The number of cancer cases observed was compared with the expected number, obtained from cancer incidence rates among men in the general population. Age-standardized incidence ratios (SIR) and their 95% confidence intervals (CI) were computed. RESULTS: A total of 19,609 person-years of observation were accumulated among HIV-positive men, and 7957 person-years among HIV-negative men. Among HIV-positive men, statistically significant increased SIR were seen for Hodgkin's disease (HD) (SIR = 8.7), liver cancer (SIR = 11.0), and cancer of the salivary glands (SIR = 33.6). An excess of lung cancer was seen among intravenous drug users (IDU), but not among homosexual men. When the risk of all non-AIDS-defining cancers was considered, HIV-positive men had a nearly twofold excess (95% CI: 1.2-2.8). A risk of similar magnitude emerged among HIV-negative IDU (95% CI: 1.0-4.5), largely attributable to lung cancer and HD. CONCLUSION: These findings confirm that HIV infection increases the risk of HD, whereas they suggest that the risk of hepatocellular carcinoma may also be enhanced by HIV infection. The observation of an elevated risk of lung cancer in both HIV-positive and HIV-negative IDU points to personal behaviours unrelated to HIV infection.

Adult↗