Evolution of HVR-1 Quasispecies after 1-Year Treatment in HIV/HCV-Coinfected Patients According to the Pattern of Response to Highly Active Antiretroviral Therapy

Hepatitis C virus (HCV) variability is mainly attributed to the ability of the virus to respond to host immune pressure, acting as a driving force for the evolution of quasispecies. This study was aimed at studying the changes in HVR-1 heterogeneity and the evolution of HCV quasispecies in HIV/HCV-coinfected patients according to the pattern of response to highly active antiretroviral therapy (HAART).

Sixteen HIV/HCV-coinfected patients harbouring HCV genotype 1 and who had been on HAART for at least 1 year, 8 showing increasing CD4+T-cell counts (immunological responders) and 8 showing a stable or decreasing CD4+ T-cell counts (immunological non-responders), were selected from a prospective cohort study.

After 1 year of HAART, 11 patients showed HIV viral load <2.6 log10 cp/ml (virological responders), and 5 showed HIV viral load above this value (virological non-responders). Plasma samples, collected before starting therapy and after 1 year of HAART, underwent clonal sequence analysis for HVR-1 region of HCV. Non-synonymous/synonymous substitutions ratio (Ka/Ks), aminoacidic complexity (normalized Shannon entropy) and diversity (p-distance), were considered as parameters of quasispecies heterogeneity. After 1 year of HAART, heterogeneity of HVR-1 quasispecies significantly decreased in virological non-responders, whereas the heterogeneity tended to increase in virological responders. The differences in the evolution were less stringent, when considering immunological response. On the other hand, profound qualitative modifications of HVR-1 quasispecies were observed only in patients with both immunological and virological HAART response.

On the whole, these findings suggest that, in patients undergoing HAART, the extent of HCV variability and the evolution of HVR-1 quasispecies is influenced by the pattern of response to antiretroviral therapy.

Open, Randomized, Multicentre Italian Trial on Peg-Ifn plus Ribavirin versus Peg-Ifn Monotherapy for Chronic Hepatitis C in HIV-Coinfected Patients on Haart

Background

Chronic hepatitis C is common and aggressive in HIV-positive patients, so the development of a well-tolerated HCV therapy is a priority. We evaluated the efficacy and safety of pegylated interferon α2b (PEG-IFN) plus ribavirin (RBV) versus PEG-IFN monotherapy in HIV/HCV-coinfected patients undergoing highly active antiretroviral therapy (HAART), and analysed the predictive factors of response.

Methods

An Italian, multicentre, open-label trial including 135 coinfected patients, randomized to PEG-IFN 1.5 μg/kg/week plus RBV 400 mg twice daily ( n=69, arm A) or PEG-IFN 1.5 μg/kg/week ( n=66, arm B) for 48 weeks. We assessed the predictive values of early virological response (EVR) at week 8 (HCV-RNA drop >2 log10 compared with baseline or undetectable levels) on sustained virological response (SVR).

Results

Fifty-five patients (28 from arm A and 27 from arm B) completed 48 weeks of therapy. At the end of treatment, 20/28 patients in arm A and 11/27 in arm B had HCV-RNA <50 IU/ml. In a per-protocol analysis, SVR was reached by 54% of patients in arm A (genotype 2–3, 11/16; genotype 1–4, 4/12) and 22% in arm B (genotype 2–3, 3/15; genotype 1–4, 3/12). In an intention-to-treat analysis, the SVR was 22% in arm A (genotype 2–3, 11/32; genotype 1–4, 4/37) versus 9% in arm B (genotype 2–3, 3/32; genotype 1–4, 3/34). The best predictors of SVR were the use of combination therapy, infection with HCV genotype 3 versus genotype 1, and EVR at week 8. Thirty patients (15 from arm A and 15 from arm B) dropped out of the trial prematurely due to side effects. The positive predictive value of EVR at week 8 was 65%, the negative predictive value was 86%.

Conclusions

PEG-IFN plus RBV can be considered a solid option for the treatment of HIV/HCV-coinfected patients. The key to successfully improving efficacy is strong compliance through strict overall patient monitoring, in order to best manage drug toxicity. EVR assessment at week 8 may become a useful stategy in the management of therapy.

Response to Haart and Gb Virus Type C Coinfection in a Cohort of Antiretroviral-Naive HIV-Infected Individuals

The prognostic role of GB virus type C (GBV-C) viraemia in HIV-infected subjects treated with highly active antiretroviral therapy (HAART) is still undefined, The aim of this analysis is to assess the relationship between GBV-C infection and response to antiretroviral therapy among HIV-infected subjects initiating HAART when antiretroviral-naive.

A prospective, observational study of 400 HIV-infected patients with measurements of GBV-C RNA, hepatitis C virus (HCV) antibodies and HCV RNA determined from plasma stored prior to HAART initiation, Time to virological (achieving HIV RNA ≤500 copies/ml) and immunological success (a CD4+ count increase of ≥200cells/μl), and the time to virological relapse (confirmed HIV RNA >500 copies/ml) were assessed by Kaplan-Meier methods and Cox proportional hazard regression model.

Of the subjects, 117 (29.3%) were GBV-C positive and, overall, 351 (87.8%) patients achieved virological success, After controlling for a number of confounders including HCV RNA, GBV-C viraemic patients experienced a significantly lower risk of HIV rebound than those who were GBV-C negative [relative hazard (RH)=0.56, 95% CI: 0.34–0.93, P=0.03], Conversely, the probability of achieving initial virological success or CD4+ count response after HAART did not differ between GBV-C-negative and -positive subjects, These results suggest that GBV-C coinfection may play a role in determining the rate of HIV rebound possibly by competing with HIV replication after HIV load has been successfully suppressed by HAART.

Variability in the Interpretation of Transmitted Genotypic HIV-1 Drug Resistance and Prediction of Virological Outcomes of the Initial Haart by Distinct Systems

High level HIV-1 drug resistance in recently infected treatment-naive individuals correlates with sub-optimal virological responses to highly active antiretroviral therapy (HAART). To determine whether genotypic HIV-1 drug resistance in chronic naive patients, as interpreted by various systems, could predict the virological outcomes of HAART, isolates from patients enrolled in a prospective observational cohort (ICoNA) prior to treatment start were genotyped. Genotypic susceptibility scores (GSS) assigned to the initial HAART regimens using the interpretations of pre-therapy resistance mutations by 13 systems were related to virological outcomes. Of 415 patients, 42 (10%) had at least one major resistance mutation. According to the different interpretations, 1.9–20.5% of patients had some level of resistance to at least one drug in the initial regimen. In multivariable analysis, GSS from two systems significantly predicted the time to virological success: Rega 5.5, for each unit increase in GSS adjusted relative hazard (RH) 1.86 [95% confidence intervals (95% CI): 1.15–3.02] and hivresistanceWeb v3, RH 1.87 (95% CI: 1.00–3.48). With three other systems, GSS showed a trend towards a significant prediction of success: Retrogram 1.6, RH 2.33 (95% CI: 0.98–5.53), Menéndez 2002, RH 2.36 (95% CI: 0.97–5.72) and Stanford hivdb, RH 2.06 (95% CI: 0.94–4.49). Genotypic resistance testing coupled with adequate interpretation in chronic naive patients can usefully identify those at risk of sub-optimal virological response to HAART.

The Management of Hepatitis B Virus/HIV-1 Co-Infected Patients Starting Their First Haart Regimen. Treating Two Infections for the Price of One Drug?

We examined the impact of a lamivudine-containing highly active antiretroviral therapy (HAART) regimen on 164 hepatitis B virus/HIV co-infected individuals starting their first HAART. Lamivudine-treated patients (accounting for 73% of the study population) showed a significantly lower level of alanine aminotransferase over follow-up [–81.1 mU/ml mean difference; 95% confidence intervals (95% CI): –30.3; –131.7, P=0.003] and a significantly reduced risk of liver-related morbidity/mortality [Relative hazard (RH)=0.07; 95% CI: 0.01–0.38, P=0.002] than those starting a lamivudine sparing-regimen.

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.

Italian multicentre study of didanosine compassionate use in advanced HIV infection. Italian BMS-906 Study Group

The aim of the present study, a multicentre trial of didanosine (ddI) compassionate use, was to identify factors associated with a better outcome in patients given ddI monotherapy. Enrolled were 1047 HIV-positive patients intolerant of and/or unresponsive to zidovudine (ZDV) therapy, with CD4+ cell counts of < 200/microliter or AIDS. Didanosine was given at a dose of 250 mg b.i.d. (patients > or = 60 kg) or 167 mg b.i.d. (patients < 60 kg). Clinical examinations and laboratory tests were performed every two months. Endpoints included death, the occurrence of a new AIDS-defining disease, or permanent discontinuation of ddI for a severe adverse event. At entry, the median CD41 cell count was 47/microliter and the median duration of prior ZDV treatment 19 months; 446 patients (43%) were classified as having AIDS. Severe toxicity occurred in 143 subjects (14%); the frequency of pancreatitis was very low (0.2%). The benefit in terms of CD4+ cell counts was greater for patients whose counts exceeded 100/microliter at entry and remained at this level until month 12 in those patients still receiving treatment. Death and/or new AIDS-defining events were observed in 374 cases (36%) over a median follow-up of eight months. AIDS dementia was observed in 11 patients (1%). Multivariate analysis of survival without disease progression showed that the factors associated with a worse outcome include the severity of immunodepression, a diagnosis of AIDS at entry, and a history of both intolerance of and clinical resistance to ZDV. Surprisingly, the patients who had received previous prolonged treatment with ZDV had a better outcome. In conclusion, severely immunodepressed patients previously administered long-term monotherapy may receive a short-term benefit from being switched to another antiretroviral drug.

[Use of esophageal atrial electrogram and an external Thera VDD pacemaker in atrial-triggered ventricular pacing in acute myocardial infarction complicated by total AV block and low cardiac output]

Aim of this short report is to present a simple and fast technique to pace in VDD mode patients with acute myocardial infarction associated with third degree AV block and haemodynamic deterioration. VDD pacing was obtained using atrial electrogram recorded by trans-oesophageal catheter and a Medtronic Thera VDD pace-maker as temporary pace-maker.

Community-acquired pneumonia in a cohort of former injection drug users with and without human immunodeficiency virus infection: incidence, etiologies, and clinical aspects

Although the association among bacterial pneumonia, human immunodeficiency virus (HIV) infection, and injection-drug use seems to have been well established, accurate estimates of the risk of community-acquired pneumonia among HIV-positive and HIV-negative injection-drug users (IDUs) are still needed. To estimate the incidence of pneumonia in a community of former IDUs, we followed 4,236 persons between 1991 and 1994; 1,114 (26.3%) were HIV-positive and 3,122 (73.7%) were HIV-negative. All patients were evaluated for pneumonia by standard criteria, a serum sample was obtained from each participant at least once a year, and laboratory values were monitored. Overall, 149 episodes of pneumonia occurred among HIV-positive patients and 61 among HIV-negative patients; incidence rates were 90.5 and 14.2 (per 1,000 person-years), respectively. The most common etiologic agents were Streptococcus pneumoniae, Chlamydia pneumoniae, and Haemophilus influenzae. Among the HIV-positive former IDUs, there was a 1.37-fold increase in the relative risk of pneumonia for every decrease of 100/mm3 in the CD4 cell count (95% confidence interval, 1.16-1.61). The incidence of community-acquired pneumonia was markedly higher among HIV-positive participants than among HIV-negative ones, a finding similar to that concerning the general population.

Rhodococcus equi infection in HIV-positive subjects: a retrospective analysis of 24 cases

Rhodococcus equi causes a rare infection in immunocompromised hosts. We describe 24 cases of infection in patients with AIDS-related complex (ARC)/acquired immunodeficiency syndrome (AIDS). Pneumonia was always the first manifestation of R. equi infection, but extrapulmonary involvement was also observed. The main sources of bacteria were sputum, bronchial washings and blood. The strains isolated were mainly susceptible to erythromycin, vancomycin, teicoplanin, rifampicin, imipenem and aminoglycosides. Initial treatment should involve an intravenously administered antibiotic combination therapy including imipenem or vancomycin or teicoplanin, followed by orally administered maintenance combination therapy. Drug combinations should be investigated for serum bactericidal activity in vitro. Surgery does not increase survival time and should only be performed in cases that do not respond to antibiotic treatment. Presumptive risks of infection (contact with horses or farm dust, or cohabiting with people affected by R. equi infection) were present in more than 50% of patients. This finding, and the frequency of bacteria in the sputum, are not sufficient proof of transmission between humans, but do suggest the need for respiratory isolation of patients affected by R. equi pneumonia.

[Bullous pneumopathy and spontaneous pneumothorax. Atypical radiologic patterns of Pneumocystis carinii pneumonia]

Pneumocystis carinii pneumonia (PCP) is certainly the most frequent opportunistic pulmonary infection in AIDS patients. Besides the conventional radiographic features demonstrating bilateral infiltrates and airspace consolidation, atypical radiologic patterns are reported in the literature, which are characterized by spontaneous pneumothorax and by the presence of bullae, cysts and areas of pulmonary cavitation. Forty consecutive PCP patients were investigated, ten of them presenting with atypical radiographic findings: 1 case of spontaneous pneumothorax with no evidence of bullae and 9 cases of bullous lung disease--5 of them complicated by spontaneous pneumothorax. Several pathogenetic hypotheses were considered; lesions evolution and the differential radiologic diagnosis were discussed. As for diagnosis, the value of chest CT scans is emphasized, together with that of HRCT which is extremely valuable to localize, characterize and evaluate bullous lesions and associated parenchymal signs.

[Ventricular stimulation triggered by esophageal atriogram: a new technique of temporary physiologic stimulation in the course of acute myocardial infarct complicated by atrioventricular block and low cardiac output]

Advanced atrio-ventricular (AV) block during acute myocardial infarction (AMI) is considered a complicating dysrhythmia as the well as mechanism responsible for occurrence of life-threatening hemodynamic changes. Often, simple VVI pacing can result insufficient in improving the decreased cardiac output. VDD pacing, which preserves atrial contribution, should represent the most effective electrical approach; therefore, it requires intracavitary placement of 2 catheters. In 10 pts (6M, 4F, mean age of 63.8 +/- 6.6 years) with advanced AV block due to AMI (4 inferior, 6 anterior) and without sinus node dysfunction, we performed stable VDD stimulation (mean 16.6 +/- 20.6 hours) using only one catheter positioned in the right ventricle while the atrial impulse, filtered (50-70 Hz) and amplified through a special device, was derived from the esophagus. Such technique is rapid and reliable, avoiding problems associated with atrial sensing and catheterization.

[Increase in blood potassium and subsequent normalization: effects on the electrocardiogram. Case report]

Significant variations in the ECG have been observed in a female aged 77 with heart failure and chronic atrial fibrillation during an occasional increase in blood potassium followed by normalization. The major phenomena observed during hyperkalemia, due to a severe dehydration, were a transient sinus rhythm with atrio-ventricular block followed by atrial activity disappearance and advent of interventricular and fascicular block. Therapeutic normalization of blood potassium leads to a progressive disappearance of intraventricular and fascicular block, a temporary sinus rhythm and finally the return to atrial fibrillation which was the steady state of the patient before the blood potassium imbalance.

[Electrophysiological mechanisms of tachyarrhythmias associated with the sick sinus syndrome (author's transl)]

Atrail programmed stimulation (APS) and His bundle recordings were performed in 24 patients with assessed sick sinus syndrome, 14 of whom had previously suffered from bouts of spontaneous paroxysmal tachycardias (Group I) and 10 with no history of previous similar complication (Group II). APS reproduced re-entry arrhythmias in 13 cases of Group I (92%). In 6 cases, junctional reciprocating tachycardia was elicited and the atrioventricular node function curve showed a typical steplike profile, consistent with longitudinal dissociation of the node itself as a cause of reciprocation. In 7 cases with previous paroxysmal atrial tachycardias, APS elicited intra-atrial re-entry arrhythmias. Absolutely no arrhythmia was elicited by APS in the 10 cases of Group II. High incidence of basal prolongation of conduction intervals was observed in both Groups (11 cases in Group I, 6 cases in Group II). Intra-atrial and/or atrio-nodel conduction delays were recognized in all the cases with intra-atrial re-entry arrhythmias. These results suggest that so called bradycardia-tachycardia syndrome should be regarded as an independent clinical form from the sick sinus syndrome, sharing with the latter the sinusal disfunction only. Re-entry mechanisms seems to be mainly responsible for the inititation of paroxysmal tachyarrhythmias: re-entry in the atrium, based on stable conduction delays, is probably correlated with scattered lesions of the same degenerative process affecting the sinus node. On the contrary, the frequent association of sick sinus syndrome with junctional paroxysmal tachycardia and its comples dissociation mechanism of the a-v node, raises the suspicion that, in such cases, two completely different processes are merely coexisting: a degenerative lesion of the sinus node and an anatomical or functional anomaly of a separate portion of the conduction system.