Roberto Gulminetti

Prevalence of and risk factors for fungal vaginitis caused by non-albicans species

OBJECTIVE Our purpose was to evaluate the prevalence of symptomatic yeast vaginitis caused by non-albicans species among patients attending a vaginitis clinic over an 8-year period. STUDY DESIGN A retrospective study of 1263 patients with symptomatic yeast vaginitis confirmed by culture techniques was performed. RESULTS The prevalence of symptomatic fungal vaginitis caused by non-albicans species increased from 9.9% (10/101) in 1988 to 17.2% (36/209) in 1995 (chi 2 for trend = 9.33, p = 0.002). Non-albicans species were found more frequently in known human immunodeficiency virus-seropositive patients (23/102 vs 143/1161, odds ratio 2.07, 95% confidence interval 1.2 to 3.46) than in seronegative subjects or subjects of unknown status for the virus. Recurrent vaginal candidiasis was an additional risk factor for vaginitis caused by non-albicans species (odds ratio 2.47, 95% confidence interval 1.72 to 3.52). The increase in non-albicans isolates during the study period was confirmed in stratified analysis and in the subgroup of self-referred patients with no history of either human immunodeficiency virus infection or recurrent vaginal candidiasis. CONCLUSION The prevalence of fungal vaginitis caused by non-albicans species has increased sharply in the setting of a vaginitis clinic. The characteristics of risk factors suggest that fungal cultures should be done routinely in human immunodeficiency virus-seropositive subjects with suspected vaginal candidiasis and in patients with recurrent vaginal infection.

NATURALLY OCCURRING RESISTANCE MUTATIONS TO INHIBITORS OF HCV NS5A REGION AND NS5B POLYMERASE IN DAA TREATMENT-NAIVE PATIENTS

BackgroundDirect-acting antiviral (DAA) agents target HCV proteins; some of these have already been approved for the treatment of HCV infection, while others are in development. However, selection of DAA-resistant viral variants may hamper treatment. The aim of this study was to illustrate potential natural DAA-resistance mutations in the HCV NS5A and NS5B regions of HCV genotypes 1a and 1b from DAA-naïve patients.MethodsDirect sequencing of HCV NS5A and NS5B regions was performed in 32 patients infected with HCV genotype 1a and 30 patients infected with HCV genotype 1b; all subjects were naïve to DAAs.ResultsIn genotype 1a strains, resistance mutations in NS5A (M28V, L31M and H58P) were observed in 4/32 (12.5%) patients, and resistance mutations in NS5B (V321I, M426L, Y448H, Y452H) were observed in 4/32 (12.5%) patients. In genotype 1b, resistance mutations in NS5A (L28V, L31M, Q54H, Y93H and I280V) were observed in 16/30 (53.3%) patients, while resistance mutations in NS5B (L159F, V321I, C316N, M426L, Y452H, R465G and V499A) were observed in 27/30 (90%) patients.ConclusionsMutations conferring DAA resistance were detected in NS5A and NS5B of HCV genotypes 1a and 1b from DAA-naïve patients. Although some mutations confer only a low level of resistance, the presence at baseline of mutated HCV variants should be taken into consideration in the context of DAA therapy.

Naturally occurring mutations to HCV protease inhibitors in treatment-naïve patients

BackgroundProtease inhibitors (PIs) to treat hepatitis C (HCV) virus infection have been approved and others are under development.ResultsThe aims of this study were to illustrate natural polymorphisms in the HCV protease and measure the frequency of PI resistance mutations in different HCV genotypes from PI-naïve patients.Direct sequencing of HCV NS3/4A protease was performed in 156 HCV patients naïve to PIs who were infected with genotype 1a (n = 31), 1b (n = 39), 2 (n = 30), 3 (n = 33) and 4 (n = 23).Amino acid (aa) substitutions associated with HCV PI resistance were found in 17/156 (10.8%) sequences. Mutations V36L, T54S, V55A/I, and Q80K/L were observed in 29% of patients with genotype 1a, and V55F, Q80L/N and M175L in 10% of patients with genotype 1b. The mutation V158M was found in 3% of patients with genotype 2, D168Q was present in 100% of patients with genotype 3 and D168E was observed in 13% of patients with genotype 4. In addition, multiple aa polymorphisms not associated with PI resistance were detected in patients with genotypes 1a, 1b and 4.ConclusionsAlthough major PI resistance mutations were not detected, other resistance mutations conferring low level resistance to PIs together with a number of natural polymorphisms were observed in proteases of PI naïve HCV patients. A more extensive analysis is needed to better evaluate the impact of baseline resistance and compensatory mutations in the efficacy of HCV PI treatment.

Early emergence of raltegravir resistance mutations in patients receiving HAART salvage regimens

The emergence of drug‐resistance mutations in HIV‐1 integrase of patients receiving HAART salvage regimens including raltegravir was investigated in 11 heavily pretreated patients (median number of treatment failures 12, range 5–22) within an expanded access program in Pavia, Italy. HIV‐1 RNA levels in plasma, CD4+ T‐cell counts and sequencing of HIV‐1 reverse transcriptase (RT), protease (PR), gp41, and integrase genes were performed at baseline and after 1, 2, 3, 6, and 12 months. The treatment baseline median HIV‐1 RNA levels in plasma decreased from 7,510 (range 118–407,107) to <50 copies/ml (range <50–7,562), while median CD4+ T‐cell counts remained unchanged (from 212 cells/µl, range 10–764 to 262 cells/µl, range 13–760). Mutations at positions involved in raltegravir resistance (E92G, G140S, Q148H, and N155H) were detected in 4 of 11 (36.3%) patients as early as 1 month after initiating salvage HAART. Of note, the E → G change at codon 92 was not reported previously. In two patients with raltegravir resistance, the simultaneous appearance of additional mutations (Y143R and E170A) with an unclear impact on susceptibility to raltegravir or on integrase activity was observed. It is concluded that raltegravir resistant HIV‐1 strains may emerge as early as 1 month after initiating HAART salvage regimens. A new mutation associated with the emergence of raltegravir resistance is described, and the simultaneous appearance of primary and secondary mutations was observed. The effect of single and multiple mutations on integrase activity, raltegravir susceptibility, and on the capacity of viral replication remains to be elucidated. J. Med. Virol. 82:116–122, 2010.

The relationship of bacterial vaginosis, Candida and Trichomonas infection to symptomatic vaginitis in postmenopausal women attending a vaginitis clinic.

OBJECTIVE To estimate the prevalence of bacterial vaginosis, Candida albicans, and Trichomonas vaginalis infections in a population of postmenopausal women with symptoms of vaginitis seen at a vaginitis clinic either as self-referred or clinician referred patients. METHODS A cross-sectional study of 148 postmenopausal women (cases) and 1564 controls of reproductive age attending a vaginitis clinic. C. albicans and T. vaginalis infections were diagnosed by culture techniques. Bacterial vaginosis was diagnosed on the basis of clinical findings. RESULTS Fifty-six (37.8%) postmenopausal women and 834 (53.3%) controls were diagnosed with T. vaginalis or C. albicans infection, or bacterial vaginosis, or mixed infection (odds ratio (OR) 0.53, 95% confidence interval (CI) 0.37-0.75). C. albicans and T. vaginalis infection were diagnosed in 34.1% (534/1564) and 1.92% (30/1564) of women of childbearing age and in 13.5% (20/148) and 10.8% of postmenopausal women, respectively. (P < 0.05 for both comparisons). The prevalence of bacterial vaginosis was similar between the two groups (14/148 in postmenopausal patients and 210/1564 in controls of reproductive age; P = 0.22). CONCLUSIONS Among postmenopausal women attending a vaginitis clinic, a defined diagnosis of bacterial vaginosis, C. albicans or T. vaginalis infection can be made in about one third of such patients. Concerning the two thirds of symptomatic women lacking such a microbiologic diagnosis, alternative causes (e.g., estrogen deficiency, nonanaerobic bacterial infections, local irritants or allergenes, and dermatologic conditions) need to be considered.

Performance of liver stiffness measurements by transient elastography in chronic hepatitis

AIM To compare results of liver stiffness measurements by transient elastography (TE) obtained in our patients population with that used in a recently published meta-analysis. METHODS This was a single center cross-sectional study. Consecutive patients with chronic viral hepatitis scheduled for liver biopsy at the outpatient ward of our Infectious Diseases Department were enrolled. TE was carried out by using FibroScan™ (Echosens, Paris, France). Liver biopsy was performed on the same day as TE, as day case procedure. Fibrosis was staged according to the Metavir scoring system. The diagnostic performance of TE was assessed by using receiver operating characteristic (ROC) curves and the area under the ROC curve analysis. RESULTS Two hundred and fifty-two patients met the inclusion criteria. Six (2%) patients were excluded due to unreliable TE measurements. Thus, 246 (171 men and 75 women) patients were analyzed. One hundred and ninety-five (79.3%) patients had chronic hepatitis C, 41 (16.7%) had chronic hepatitis B, and 10 (4.0%) were coinfected with human immunodeficiency virus. ROC curve analysis identified optimal cut-off value of TE as high as 6.9 kPa for F ≥ 2; 7.9 kPa for F ≥ 3; 9.6 kPa for F = 4 in all patients (n = 246), and as high as 6.9 kPa for F ≥ 2; 7.3 kPa for F ≥ 3; 9.3 kPa for F = 4 in patients with hepatitis C (n = 195). Cut-off values of TE obtained by maximizing only the specificity were as high as 6.9 kPa for F ≥ 2; 9.6 kPa for F ≥ 3; 12.2 kPa for F = 4 in all patients (n = 246), and as high as 7.0 kPa for F ≥ 2; 9.3 kPa for F ≥ 3; 12.3 kPa for F = 4 in patients with hepatitis C (n = 195). CONCLUSION The cut-off values of TE obtained in this single center study are comparable to that obtained in a recently published meta-analysis that included up to 40 studies.

Plasma Levels of Bacterial DNA in HIV Infection: The Limits of Quantitative Polymerase Chain Reaction

To the Editor—In a recent article, Jiang et al [1] showed that blood levels of bacterial DNA, as determined by quantitative polymerase chain reaction (PCR) on 16S ribosomal DNA fragments, were significantly higher in human immunodefi-ciency virus (HIV)–infected patients than were those in uninfected control patients. Moreover, the level of bacterial DNA in the blood was shown to decrease after an-tiretroviral treatment. Blood levels of 16S ribosomal DNA could be regarded as an indicator of the translocation of microbial molecules from the gut lumen to other body compartments. This could be responsible for chronic activation of the immune system and could have a role in AIDS progression.

Development and persistence of DAA resistance associated mutations in patients failing HCV treatment

BACKGROUND Direct-acting antiviral agents (DAAs) combined with pegylated-interferon (PegIFN) and ribavirin (RBV) are still a standard treatment in patients with genotype 1HCV infection. However, virologic response could be impaired by baseline or early selection of resistant HCV strains. OBJECTIVES The aim of this study was to determine the onset and persistence of resistance-associated mutations (RAMs) in the NS3 and NS5B genes of DAA-naïve patients failing treatment. STUDY DESIGN Direct sequencing of HCV NS3 was performed in 49 DAA-naïve patients with HCV genotype 1 infection. RESULTS Eight out of 23 patients (34.7%) failed PegIFN/RBV/telaprevir during the 12-weeks of therapy. Treatment failure was associated with the development of RAMs at amino-acids 36,54,80 and 155 of the HCV protease in 6/8 patients (75%). Among patients treated with PegIFN/RBV/boceprevir treatment, 4/18 (22.2%) failed therapy. Of these, 2 (50%) carried virus strains which developed a RAM at amino-acids 54 and 155. Among HCV strains with RAMs, 7 belonged to genotype 1a and 1 to 1b. Finally, in 6/10 (60%) patients, drug-resistant variants could still be detected for up to 3-7 months after stopping therapy. CONCLUSIONS A higher rate (p=0.49) of treatment failure was observed in patients receiving telaprevir- compared to the boceprevir-based combination. In addition, compared with genotype 1b, genotype 1a was associated with higher rates (p=0.01) of treatment failure due to virus resistant strains. Resistance testing at baseline and during DAA treatment should be taken into consideration when treating patients with new HCV combination therapies.

HIV integrase variability and genetic barrier in antiretroviral naïve and experienced patients

BackgroundHIV-1 integrase (IN) variability in treatment naïve patients with different HIV-1 subtypes is a major issue. In fact, the effect of previous exposure to antiretrovirals other than IN inhibitors (INI) on IN variability has not been satisfactorily defined. In addition, the genetic barrier for specific INI resistance mutations remains to be calculated.MethodsIN variability was analyzed and compared with reverse transcriptase (RT) and protease (PR) variability in 41 treatment naïve and 54 RT inhibitor (RTI) and protease inhibitor (PRI) experienced patients from subjects infected with subtype B and non-B strains. In addition, four HIV-2 strains were analyzed in parallel. Frequency and distribution of IN mutations were compared between HAART-naïve and RTI/PI-experienced patients; the genetic barrier for 27 amino acid positions related to INI susceptibility was calculated as well.ResultsPrimary mutations associated with resistance to INI were not detected in patients not previously treated with this class of drug. However, some secondary mutations which have been shown to contribute to INI resistance were found. Only limited differences in codon usage distribution between patient groups were found. HIV-2 strains from INI naïve patients showed the presence of both primary and secondary resistance mutations.ConclusionExposure to antivirals other than INI does not seem to significantly influence the emergence of mutations implicated in INI resistance. HIV-2 strain might have reduced susceptibility to INI.

Therapeutic monitoring and variability of atazanavir in HIV-infected patients, with and without HCV coinfection, receiving boosted or unboosted regimens.

Background: Adequate plasma trough concentrations (Ctrough) of protease inhibitors are required to maintain antiviral activity throughout the dosing interval. Therapeutic drug monitoring is used in clinical practice to optimize dosage and avoid toxic or subtherapeutic drug exposure. The pharmacokinetic variability of Atazanavir (ATV) can be relatively large, as a result of several factors. One of the affecting factors may be hepatic impairment due to hepatitis C virus (HCV) coinfection. Methods: We collected trough plasma samples from human immunodeficiency virus (HIV)-1-infected outpatients, with and without HCV coinfection and/or cirrhosis, receiving stable highly active antiretroviral therapy containing ATV. In the total population, we mainly compared the 2 regimens: 300ATV + 100RTV OD [ritonavir (RTV), once daily (OD)] versus 400ATV OD. We used a threshold value of 0.15 μg/mL, based on the proposed therapeutic range (0.15-0.85 μg/mL). Plasma concentrations of ATV were determined by a validated assay using high-performance liquid chromatography with ultraviolet detection. A total of 214 HIV-infected outpatients were included. For each regimen, we compared 3 groups of subjects: HIV+/HCV−, HIV+/HCV+, and HIV+/HCV+ with cirrhosis. Results: In the whole study population, we observed a large variability and found suboptimal Ctrough levels (<0.15 μg/mL) in 23 subjects (2 belonging to the 300/100 OD group and 21 to the 400 OD group). For the standard dosage regimen of 300ATV + 100RTV OD, we did not find a statistical difference between HIV-infected patients without HCV coinfection versus HIV-infected patients with HCV coinfection: median 0.85 (interquartile range 0.53-1.34) and 0.95 (0.70-1.36) μg/mL, respectively. In HIV+/HCV+-infected patients with cirrhosis, we found a median Ctrough of 0.70 (0.43-1.0) μg/mL, with no statistical difference when compared with HIV+/HCV− infected patients. For the 400ATV OD (n = 90) dosage regimen, the total median ATV Ctrough was 0.40 (0.23-1.0) μg/mL. In this group, we found a statistically significant difference between HIV+/HCV− and HIV+/HCV+-infected patients: median Ctrough was 0.23 (0.11-0.42) and 0.52 (0.20-1.0) μg/mL, respectively. In HIV+/HCV+ subjects with cirrhosis, the Ctrough median value was 0.42 (0.13-0.75) μg/mL, and there was a significant difference when compared with HIV patients without coinfection. Conclusions: Therapeutic drug monitoring of ATV in patients receiving unboosted regimen may be useful to identify those HIV-infected subjects, with or without HCV coinfection, who may benefit from adding low RTV doses, or the subset of patients in whom removal of RTV could be attempted without the risk of suboptimal plasma ATV exposure.