Antibiotic Resistance to Molecules Commonly Prescribed for the Treatment of Antibiotic-Resistant Gram-Positive Pathogens: What Is Relevant for the Clinician?

Antibiotic resistance in Gram-positive pathogens is a relevant concern, particularly in the hospital setting. Several antibiotics are now available to treat these drug-resistant pathogens, such as daptomycin, dalbavancin, linezolid, tedizolid, ceftaroline, ceftobiprole, and fosfomycin. However, antibiotic resistance can also affect these newer molecules. Overall, this is not a frequent phenomenon, but it is a growing concern in some settings and can compromise the effectiveness of these molecules, leaving few therapeutic options. We reviewed the available evidence about the epidemiology of antibiotic resistance to these antibiotics and the main molecular mechanisms of resistance, particularly methicillin-resistant Sthaphylococcus aureus, methicillin-resistant coagulase-negative staphylococci, vancomycin-resistant Enterococcus faecium, and penicillin-resistant Streptococcus pneumoniae. We discussed the interpretation of susceptibility tests when minimum inhibitory concentrations are not available. We focused on the risk of the emergence of resistance during treatment, particularly for daptomycin and fosfomycin, and we discussed the strategies that can be implemented to reduce this phenomenon, which can lead to clinical failure despite appropriate antibiotic treatment. The judicious use of antibiotics, epidemiological surveillance, and infection control measures is essential to preserving the efficacy of these drugs.

A prospective evaluation of maraviroc administration in patients with advanced HIV disease and multiple comorbidities: focus on efficacy and tolerability issues.

In our HIV outpatient centre where over 1,200 patients are followed, maraviroc as an entry inhibitor was introduced in 2010. We aimed to assess the background, the therapeutic challenges and the prospective monitoring of all patients treated with a combination antiretroviral therapy (cART) including maraviroc. Sixty-six patients started a maraviroc-containing cART with a history of HIV infection lasting 13.9±10.7 years. This interim analysis presents patients who had at least 12 (mean 16.9±12.8) months of follow-up. One to 17 previous cART changes prompted the introduction of maraviroc in rescue regimens in the great majority of patients considered (53 of 66); in 13 cases, maraviroc was given to patients with advanced HIV disease and no immune recovery after 2-3 years of a virologically-effective cART. The most frequent companion antiretroviral agents were: darunavir/ritonavir (51 cases), raltegravir (49 subjects), and etravirine (36 cases). The most common underlying conditions were: AIDS (41 cases), liver cirrhosis (21), AIDS-related or other malignancies (20 cases), major cardiovascular events (18 cases), osteonecrosis and haemodialysis-treated kidney failure (3 cases each). A chronic HCV and HBV hepatitis were of concern in 25 and 13 patients. The addition of maraviroc added favourably to clinical-laboratory markers of HIV disease progression, and those of comorbid conditions. HIV viraemia became (or remained) undetectable in 55 patients of 66 (83.3%). An improvement in CD4+ count was observed in all 66 patients, based on a mean 24.9±19.2% increase versus baseline, paralleled by an improvement in mean absolute CD4+ count of 134.7±121.1 cells/µL. A tendency towards an increased mean and peak CD4+ count was observed in the subgroup receiving a maraviroc-raltegravir-based cART. As no clinical-laboratory adverse events attributable to maraviroc occurred, nobody discontinued the study drug. Only mild-transient gastrointestinal disturbances, fatigue and anorexia, were reported during maraviroc administration, but their relationship with the study drug was difficult to assess because of the multiple comorbidities and polypharmacy. Our preliminary experience with maraviroc, even considering the limits of the proportionally reduced sample, the patients' salvage stage of advanced disease and the related-unrelated morbidities, underlines its excellent efficacy and safety profile.

Tenofovir/emtricitabine/efavirenz plus rosuvastatin decrease serum levels of inflammatory markers more than antiretroviral drugs alone in antiretroviral therapy-naive HIV-infected patients.

OBJECTIVES: Statins are lipid-lowering drugs that exhibit anti-Inflammatory and immune-modulatory properties, leading to a reduction of serum levels of C-reactive protein (CRP) in the general population. DESIGN: To assess the anti-inflammatory effects of statins in HIV-infected patients, because very limited data are available today. METHODS: Longitudinal, observational study of HIV-infected adult patients naive to antiretroviral therapy who started tenofovir/emtricitabine/efavirenz and were followed-up for 48 weeks. Patients with baseline normal cholesterol level and taking only antiretroviral drugs (group A) were compared to those with baseline hypercholesterolemia who received rosuvastatin (10 mg daily) in association with antiretroviral treatment (group B). The primary observation was change in serum markers of inflammation (high-sensitivity C-reactive protein [hsCRP], interleukin-6 [IL-6], interleukin-8 [IL-8]) and tumor necrosis factor-α [TNF- α]) in both groups, whereas secondary observations include variations in CD4 lymphocyte count, HIV viral load, and occurrence of adverse events. RESULTS: Eighty-six patients were enrolled into the study: 46 in group A and 40 in group B. After 48 weeks, patients treated with antiretroviral therapy plus rosuvastatin had significantly greater decreases in serum concentrations of all Inflammatory markers than those taking antiretroviral therapy only. Changes in mean levels of hsCRP and TNF-α were -35.1% and -22.4% in group B and -8.2% and 5.4% in group A, respectively (P < .001, for both parameters). No significant differences in immunovirological parameters and safety profile were reported across the compared groups. CONCLUSIONS: Our findings suggest that tenofovir/emtricitabine/efavirenz plus rosuvastatin has a greater antiInflammatory effect than antiretroviral drugs only.

Prevalence of renal disease within an urban HIV-infected cohort in northern Italy.

BACKGROUND: Renal disease is an increasingly recognized noninfectious comorbidity associated with human immunodeficiency virus (HIV) infection. METHODS: Our retrospective, cross-sectional study evaluated prevalence of nephropathy among HIV-infected patients followed up in our outpatient clinic during the year 2011. Renal dysfunction and chronic kidney disease (CKD) were defined as estimated glomerular filtration rate (eGFR) <90 ml/min per 1.73 m(2) and as renal damage or eGFR <60 ml/min per 1.73 m(2) over a 3-month or greater period, respectively. RESULTS: We enrolled 894 HIV-infected patients with a mean age of 44.2 years and a mean current CD4 lymphocyte count of 508 cells/mm(3). The prevalence of renal dysfunction and CKD was 27.4 and 21.3 %, respectively. Older age, male gender, hypertension, diabetes, proteinuria, hypertriglyceridemia, lower nadir CD4 cell count, current use of tenofovir or tenofovir plus a ritonavir-boosted protease inhibitor were independently associated with renal dysfunction. CONCLUSION: Renal dysfunction is a frequent comorbidity among HIV-infected persons and requires a careful clinical and laboratory monitoring of renal function.

Raltegravir use prospectively assessed in a major HIV outpatient clinic in Italy: sample population, virological-immunological activity, and tolerability profile.

Raltegravir, as the first HIV integrase inhibitor, has been used and prospectively monitored since 2010 in our HIV outpatient centre, where over 1,200 patients are monitored. The aim of our report is to perform an interim assessment of the background, the safety profile and the clinical-laboratory monitoring of all patients treated with a combination antiretroviral therapy (cART) including raltegravir, for at least 12 months. In all, 109 pretreated patients started a raltegravir-containing cART when aged 44.8 plus or minus 19.2 years, with a history of HIV infection lasting 13.4 plus or minus 9.7 years. All subjects were monitored for at least 12 months (mean 17.2 plus or minus 10.3 months). In the vast majority of cases (93 of 109: 85.3%), multiple (3-16) prior cART changes prompted raltegravir introduction in advanced-salvage lines: 72 of 109 (66.1%) patients had even developed a concurrent triple-class resistance to anti-HIV compounds. The most frequent companion antiretroviral agents were: darunavir/ritonavir (75 cases), maraviroc (47 subjects), and etravirine (38 cases). The most common underlying conditions were: AIDS (46 patients), liver cirrhosis (31 cases), AIDS-related or other malignancies (23 cases), and major cardio-cerebro-vascular events (18 cases). A chronic HCV and HBV hepatitis were of concern in 48 and 23 patients, respectively. The adjunct of raltegravir favourably affected all clinical-laboratory markers of HIV disease progression, and those of the broad spectrum of comorbidities, except for two patients who failed the raltegravir-containing cART due to insufficient adherence. Despite the already compromised clinical situation, a minority of subjects experienced mild-transient clinical-laboratory untoward events possibly attributable to raltegravir, such that no patients discontinued raltegravir during the observation period. Only three AIDS-defining conditions became apparent during raltegravir-based cART; chemotherapy and/or radiotherapy cycles were performed as scheduled in patients suffering from cancer; chronic hepatitis B and C progressed to liver cirrhosis and/or hepatocarcinoma in only 2 and 6 patients. Otherwise, treatment with pegylated interferon-ribavirin became feasible in 25 patients of 48 with chronic HCV. During raltegravir-containing cART, neither autoimmune disorders nor novel malignancies were diagnosed. Only mild-transient gastrointestinal disorders, fatigue, dizziness, insomnia and cutaneous rash were reported, although their relationship with the study drug was difficult to assess due to multiple comorbidities and polypharmacy. Abnormal liver function testings were observed in 57 patients (52.3%), all suffering from concurrent hepato-biliary disorders. Significant increases in serum lipids and/or lipase levels versus baseline values were never registered: serum lipid levels significantly improved after raltegravir introduction. Our experience with raltegravir underlines its excellent efficacy and safety profile, which exploits a novel mechanism of action, and displays no cross-resistance with any other antiretroviral. A progressively extended prescription in naive patients and early cART lines will allow the therapeutic potential of raltegravir to be exploited.

The mycoarray as an aid for the diagnosis of an imported case of histoplasmosis in an Italian traveler returning from Brazil.

We describe an imported case of histoplasmosis, whose serological profile was established by means of a protein-based microarray platform, the recently described mycoarray. Because of its peculiarities, such a novel tool greatly facilitates the rapid and multiparametric assessment of patients' serological status and lends itself to be employed as an aid in the diagnosis of primary mycoses, especially in nonendemic countries.

Incidence of renal toxicity in HIV-infected, antiretroviral-naïve patients starting tenofovir/emtricitabine associated with efavirenz, atazanavir/ritonavir, or lopinavir/ritonavir.

OBJECTIVES: We performed a retrospective cohort study of HIV-infected antiretroviral-naïve patients starting a first antiretroviral therapy with tenofovir/emtricitabine plus efavirenz (EFV), atazanavir/ritonavir (ATV/r), or lopinavir/ritonavir (LPV/r). METHODS: The incidence of renal impairment or proximal tubular dysfunction was evaluated during a 12-month follow-up. Renal impairment was diagnosed by a reduced estimated glomerular filtration rate (eGFR) calculated using the Modification of Diet in Renal Disease (MDRD) formula, and tubular dysfunction was diagnosed when ≥ 2 among proteinuria, glucosuria, hypouricaemia, hypophosphataemia, and hypokalaemia, were identified. RESULTS: A total of 235 patients were enrolled: 82 taking EFV, 78 ATV/r, and 75 LPV/r. The mean decline in eGFR after the 12-month follow-up was significantly greater in subjects treated with ATV/r (-10.4 ml/min/1.73 m(2)) than in those receiving EFV (- 5.1; p = 0.002) or LPV/r (-4.8; p = 0.003). Similarly, a significantly higher incidence of proximal tubulopathy was observed among ATV/r-treated patients (14.1%) compared with patients receiving EFV (4.9%) or LPV/r (5.3%). CONCLUSIONS: In our retrospective study, naïve patients receiving tenofovir/emtricitabine and ATV/r for 12 months showed a significantly higher decline in eGFR and a significantly higher incidence of proximal tubulopathy than those receiving tenofovir/emtricitabine plus EFV or LPV/r, even though clinically evident renal toxicity associated with tenofovir-based treatment is a very uncommon event.

Two-year treatment with rosuvastatin reduces carotid intima-media thickness in HIV type 1-infected patients receiving highly active antiretroviral therapy with asymptomatic atherosclerosis and moderate cardiovascular risk.

Recent studies have shown that rosuvastatin significantly decreases serum levels of inflammatory biomarkers and slows progression of carotid atherosclerosis in the general population. However, there are no data about its effect on progression of atherosclerosis in HIV-infected patients. Adult patients with HIV infection, on stable antiretroviral therapy, with asymptomatic carotid atherosclerosis and hypercholesterolemia, who started a rosuvastatin treatment at 10 mg daily during the period 2007-2009 were enrolled and followed-up for 24 months. Thirty-six patients (30 males) were enrolled, with a mean age of 49 years, a mean duration of current antiretroviral therapy of 38 months, and a mean 10-year risk of myocardial infarction of 18.5%. Rosuvastatin led to a significant decrease in mean values of intima-media thickness in all extracranial carotid arteries, with the greatest magnitude observed in carotid bifurcations (a mean decrease of 18.7% in the right artery and of 21.4% in the left artery) and in internal carotid arteries (a mean decrease of 23.7% in the right artery and of 25.6% in the left artery). Moreover, there was a significant reduction in mean levels of total cholesterol, low-density lipoprotein (LDL) cholesterol, and triglycerides versus respective baseline values associated with a significantly decreased mean cardiovascular risk. The treatment with rosuvastatin was well tolerated, and serious adverse events were not reported. A 24-month treatment with rosuvastatin in HIV-infected patients on highly active antiretroviral therapy (HAART) with subclinical atherosclerosis and a moderate cardiovascular risk seems to promote significantly favorable changes in carotid atherosclerosis, associated with a favorable effect on serum lipid levels and a good tolerability profile.

FDG PET/CT is useful for the interim evaluation of response to therapy in patients affected by haematogenous spondylodiscitis.

PURPOSE: Antibiotic therapy in patients affected by discitis is often empirical. Therefore, early evaluation of response to therapy is important. In many patients inflammatory indexes are low during all the phases of the diseases or are altered by concomitant diseases. The aim of the study was to assess the possible role of FDG PET/CT for the early evaluation of response to therapy in patients affected by infective discitis, in comparison to C-reactive protein (CRP) serum levels. METHODS: Enrolled in the study were 38 patients diagnosed with haematogenous infective discitis. Of the 38 patients, 7 had tubercular infection, 1 fungal infection and 30 pyogenic discitis. Four patients were excluded because the second PET/CT scan was not performed. Thus 34 patients (18 women, mean age 64 years) were analysed. All the patients included underwent a FDG PET/CT scan and determination of CRP level at baseline and again 2 to 4 weeks after the start of therapy. The PET results in terms of SUV of the first and second scans (SUV1 and SUV2) and delta-SUVmax were compared to the inflammatory indexes and clinical status during therapy. RESULTS: The mean SUVmax at diagnosis was 8.6 ± 3.7. The mean CRP level at diagnosis was 3.8 ± 3.8 mg/dl. A progressive clinical response was seen in 26 patients and 8 patients showed no response. SUV1 was not correlated with the baseline CRP level (CRP1, p = 0.7) and SUV2 was not correlated with the CRP level at the time of the second scan (CRP2, p = 0.4). In responders, SUV2 and CRP2 were significantly lower than SUV1 and CRP1 (p < 0.0001 and p = 0.001, respectively). ROC curves for delta-SUVmax showed a sensitivity of 82 % and a specificity of 82 % with a cut-off of 34 %. ROC curves for SUV2 showed a sensitivity of 83 % and a specificity of 46 % with a cut-off of 6.4. ROC curves for delta-CRP showed a sensitivity of 67 % and a specificity of 89 % with a cut-off of 74 %. ROC curves for CRP2 showed a sensitivity of 65 % and a specificity of 70 % with a cut-off of 0.7 mg/dl. No statistically significant difference was found between delta-SUVmax AUC and delta-CRP AUC (p = 0.5). CONCLUSION: Delta-SUVmax provided a higher sensitivity and specificity for identifying responders. SUV2 provided comparable sensitivity, but significantly lower specificity. CRP level performed less well for identifying responders. There was no significant difference in the global performance of the two tests (delta-SUVmax AUC and delta-CRP AUC). However, the higher sensitivity of delta-SUVmax for the early identification of responders may have an important clinical impact in guiding antibiotic therapy especially in patients with a noninformative CRP test at diagnosis.

Lopinavir/ritonavir trough concentrations with the tablet formulation in HIV-1-infected women during the third trimester of pregnancy.

OBJECTIVES: An observational, open-label study was performed to assess changes of lopinavir/ritonavir plasma concentrations during pregnancy. METHODS: Adult HIV-1-infected women during the third trimester of pregnancy and on stable antiretroviral treatment including zidovudine/lamivudine plus lopinavir/ritonavir tablets (400/100 mg twice daily) were asked to participate. This group was compared with a group of non-pregnant HIV-1-infected women receiving the same antiretroviral regimen. The trough plasma concentration (C(trough)) of lopinavir and ritonavir was assessed at steady-state by a validated high-performance liquid chromatography (HPLC)-tandem mass spectrometry method. RESULTS: A total of 41 HIV-positive female patients were enrolled in the study, with a median age of 28 y (range 20-37 y). These patients were stratified into 2 groups: 21 women in the third trimester of pregnancy (group A) and 20 non-pregnant women (group B). The geometric mean (95% confidence interval (CI)) plasma C(trough) of lopinavir was 4205 (2418-6896) ng/ml in group A and 5098 (3187-8084) ng/ml in group B. The reduction in lopinavir plasma levels observed in group A was not significant (geometric mean ratio 0.87, 95% CI 0.62-1.32; p = 0.411). No correlation was found between lopinavir plasma levels and adverse events (such as diarrhoea and hyperlipidaemia) or immunological parameters of HIV disease, and no changes in plasma HIV viral load were reported. CONCLUSION: In this study, a slight but not significant decrease in the plasma lopinavir C(trough) was found during the third trimester of pregnancy, suggesting that standard dosing of the tablet formulation is also appropriate during the later stages of pregnancy.