Prevalence and determinants of resistance mutations in HIV-1-infected patients exposed to integrase inhibitors in a large Italian cohort.

OBJECTIVES: The aim of the study was to analyse the prevalence of integrase resistance mutations in integrase strand transfer inhibitor (INSTI)-experienced HIV-1-infected patients and its predictors. METHODS: We selected HIV-1 integrase sequences from the Antiviral Response Cohort Analysis (ARCA) database, derived from INSTI-experienced patients between 2008 and 2017. Differences in the prevalence of resistance to raltegravir (RAL), elvitegravir (EVG) and dolutegravir (DTG) were assessed by χ2 test and predictors of resistance were analysed by logistic regression. RESULTS: We included 462 genotypes from INSTI-exposed individuals: 356 'INSTI-failing' patients and 106 'previously INSTI-exposed' patients (obtained a median of 42 weeks after INSTI discontinuation [interquartile range (IQR) 17-110 weeks]). Overall, at least low-level resistance (LLR) to any INSTI (Stanford 8.5 algorithm) was detected in 198 (42.9%) cases. The most frequent INSTI resistance mutation was N155H, followed by Q148H/K/R, G140A/C/S, E138A/K/T and Y143C/H/R. Y143R and E138A were more prevalent in viral subtype B versus non-B [5.2 versus 1.5%, respectively (P = 0.04), and 3.1 versus 0%, respectively (P = 0.02)]. Overall, the Q148H/K/R plus G140A/C/S and/or E138A/K/T pattern, defining an intermediate level of resistance to DTG, was detected in 70 (15%) cases. Independent predictors of at least LLR to any INSTI were current use versus past use of INSTIs, a lower genotypic sensitivity score (GSS) for contemporary antiretroviral drugs used, and having an integrase sequence obtained in calendar year 2016 as compared to 2008-2009. CONCLUSIONS: The results support integrase resistance testing in INSTI-experienced patients. Emergence of INSTI resistance is facilitated by the reduced genetic barrier of the regimen as a consequence of resistance to companion drugs. However, INSTI resistance may become undetectable by standard population sequencing upon INSTI discontinuation.

Dolutegravir (DTG)-containing regimens after receiving raltegravir (RAL) or elvitegravir (EVG): Durability and virological response in a large Italian HIV drug resistance network (ARCA).

BACKGROUND: Dolutegravir (DTG) is a next-generation HIV integrase inhibitor (INI) with an increased genetic barrier to resistance with respect to raltegravir (RAL) or elvitegravir (EVG). Few data are available on the durability of DTG-containing regimens. OBJECTIVES: We aimed at investigating the duration of the DTG-containing regimen, the occurrence of an HIV-1 RNA blip, and factors associated with DTG virological response. STUDY DESIGN: From the Antiviral Response Cohort Analysis database, we selected 89 HIV-1-positive four-class-experienced subjects who started DTG after receiving RAL or EVG. Factors associated with durability and virological response were analysed by logistic regression. RESULTS: After a median duration of 18.8 [0.4-76.2] months, 79/89 (88.8%) subjects were still on DTG. All subjects remaining on DTG at the end of follow-up had undetectable HIV-1 RNA, compared to 5/10 subjects who discontinued DTG. DTG discontinuation was less frequent in patients who had experienced ≥10 regimens (HR 0.11, p = 0.040). The probability of having an HIV-1 RNA positive value at the last follow-up significantly increased in patients with non-B HIV-1 subtype (HR 5.77, p < .001) and significantly decreased in patients with CD4 nadir >200/µL (HR 0.29, p = 0.038), with more than 10 previous regimens (HR 0.27, p = 0.040), and who harbored virus with IN mutations (HR 0.12, p = 0.023) at DTG start. CONCLUSIONS: After previous exposure to first-generation INIs, treatment with DTG showed long durability and did not show virological rebound after virological suppression. Subjects infected with a non-B HIV-1 subtype had a greater risk of having detectable HIV-1 RNA at the last observation.

Impact of transmitted HIV-1 drug resistance on the efficacy of first-line antiretroviral therapy with two nucleos(t)ide reverse transcriptase inhibitors plus an integrase inhibitor or a protease inhibitor.

Objectives: To examine the impact of transmitted drug resistance (TDR) on response to first-line regimens with integrase strand transfer inhibitors (INSTIs) or boosted protease inhibitors (bPIs). Methods: From an Italian observational database (ARCA) we selected HIV-1-infected drug-naive patients starting two NRTIs and either an INSTI or a bPI, with an available pre-ART resistance genotype. The endpoint was virological failure (VF; plasma HIV-1 RNA >200 copies/mL after week 24). WHO surveillance drug resistance mutations and the Stanford algorithm were used to classify patients into three resistance categories: no TDR (A), TDR but fully-active ART prescribed (B), TDR and at least low-level resistance to one or more prescribed drug (C). Results: We included 1365 patients with a median follow-up of 96 weeks (IQR 54-110): 1205 (88.3%) starting bPI and 160 (11.7%) INSTI. Prevalence of TDR was 6.1%, 12.5%, 2.6% and 0% for NRTI, NNRTI, bPI and INSTI, respectively. Cumulative Kaplan-Meier estimates for VF at 48 weeks were 11% (95% CI 10.1%-11.9%) for the bPI group and 7.7% (95% CI 5.4%-10%) for the INSTI group. In the INSTI group, cumulative estimates for VF at 48 weeks were 6% (95% CI 4%-8%) in resistance category A, 5% (95% CI 1%-10%) in B and 50% (95% CI 30%-70%) in C (P < 0.001). Resistance category C [versus A, adjusted hazard ratio (aHR) 12.6, 95% CI 3.2-49.8, P < 0.001] and nadir CD4 (+100 cells/mm3, aHR 0.6, 95% CI 0.4-0.9, P = 0.03) predicted VF. In the bPI group, VF rates were not influenced by baseline resistance. Conclusions: Our data support the need for NRTI resistance genotyping in patients starting an INSTI-based first-line ART.

Usutu virus infections in humans: a retrospective analysis in the municipality of Modena, Italy.

OBJECTIVE: To monitor the spread and to evaluate the role for public health of Usutu virus (USUV) in an endemic area of Italy. METHODS: The survey was retrospectively conducted by detecting USUV RNA and USUV antibodies in cerebrospinal fluid and serum samples collected between 2008 and 2011 from 915 patients with or without neurologic impairments in the area of the municipality of Modena, Italy. Organs of birds and pools of mosquitoes were also tested for USUV RNA. Positive samples were partially sequenced and used for phylogenetic analysis. RESULTS: The presence of USUV RNA (1.1%; 95% confidence interval (CI) 0.6-2.0) was significantly (p <0.05) higher than that of West Nile virus (0%; 95% CI 0-0.33). USUV antibody level was 6.57% (95% CI 4.87-8.82), and it was significantly higher (p <0.05) compared to that of West Nile virus (p 2.96, 95% CI 1.89-4.62). Partial genome sequencing of USUV strains detected in humans, birds and mosquitoes revealed high nucleotide sequence identity within them and with the USUV strains isolated in Central Europe. CONCLUSIONS: USUV infection in humans is not a sporadic event in the studied area, and USUV neuroinvasiveness has been confirmed.

Characteristics and outcome predictors of patients involved in an outbreak of Burkholderia cepacia complex.

A Burkholderia cepacia complex outbreak occurred among ventilated non-cystic fibrosis patients in an intensive care unit (ICU) in Italy: 33 colonized and 13 infected patients were included in a retrospective study aimed at investigating factors related to clinical infection and mortality. Demographic/clinical conditions and mortality did not vary significantly between colonized and infected patients, both groups showing high mortality rates compared with the overall ICU population and similar to that observed in patients with other infections. In multivariate regression analysis, disease severity (defined by the Simplified Acute Physiology Score II) and age were the only independent predictors of early mortality (odds ratio: 1.12; 95% confidence interval: 1.02-1.26; and 1.07; 1.01-1.15, respectively).

Prevalence of etravirine (ETR)-RAMs at NNRTI failure and predictors of resistance to ETR in a large Italian resistance database (ARCA).

The prevalence of drug resistance associated with the failure of non-nucleoside reverse transcriptase inhibitor (NNRTI)-based regimens and the predictors of resistance to Etravirine (ETR) were assessed in 2854 subjects: 39 < 18 (paediatric) and 2815 ≥ 18 (adult) years old. These subjects failed to respond to their current NNRTI treatment, were three-class experienced and had been exposed to NNRTI for ≥3 months. A total of 1827 adult (64.9%) and 32 paediatric subjects (82.1%) harboured the virus with at least one ETR mutation. V179I, Y181C and G190A were the most frequent mutations in both groups. A significantly increased risk of ETR resistance with all three algorithms (Monogram (MGR) >3, Tibotec (TBT) >2 and enhanced MGR (ENH) ≥4) emerged in the paediatric population. Multivariate analysis revealed an increased risk of developing TBT >2 for NNRTI exposure, ENH ≥4 for NNRTI and EFV exposure in paediatric subjects; NVP exposure and higher (≥3.5 log10) HIV-RNA values for all three algorithms in adult subjects, whereas CD4 ≥ 200/µL appeared to be protective. The risk of being ETR resistant was more than doubled for paediatric vs. adult subjects, probably due to a more extensive use of NNRTI and an incomplete virological control.

Prevalence of HIV-1 integrase mutations related to resistance to dolutegravir in raltegravir naïve and pretreated patients.

The prevalence of HIV-1 integrase mutations related to resistance to the next-generation integrase inhibitor (INI), dolutegravir (DTG), was assessed in 440 INI-naïve subjects and in 120 patients failing a raltegravir (RTG)-containing regimen. Of the mutations selected by DTG in vitro, S153FY was not detected in any isolate while L101I and T124A were highly prevalent in both groups and significantly associated with non-B subtype. RTG-selected double and triple mutants, mostly the G140S/Q148H variant, were detected in only 32 (26.7%) RTG-treated patients. As L101I and T124A do not appear to exert any major effect in vivo and double and triple mutants resistant to DTG are infrequently selected by RTG, DTG can be effectively used in INI-naïve patients and may retain activity in many patients failing RTG.

Low prevalence of human papillomavirus infection in the healthy oral mucosa of a Northern Italian population.

BACKGROUND: Oral cancer is the sixth most common malignancy in developed countries, representing almost 3% of malignant tumors. Tobacco use and alcohol consumption are well-established risk factors. However, the observation that most patients with oral cancer have not been exposed to these risk factors suggests that additional causes may promote oral carcinogenesis. A link has been suggested between human papillomavirus (HPV) and oral cavity cancer but the significance of HPV contribution to oral carcinogenesis as well as the prevalence of HPV infection in normal oral cavity mucosa remains debated. METHODS: In this study, the prevalence of oral HPV infection was evaluated in 81 randomly selected Northern Italian subjects with clinically normal oral mucosa using a nested PCR on DNA extracted by oral smears. RESULTS AND CONCLUSIONS: No HPV-related lesions were detectable in any of the smears analyzed by cytological approach. nPCR identified HPV DNA in only one (1.2%) of the specimens obtained from clinically healthy oral mucosa and subsequent characterization assigned the positive case to HPV type 90. These data suggest that the incidence of HPV infection in the healthy population might be very low and that other risk factors are likely responsible to promote oral carcinogenesis.

Prevalence of human herpesvirus-6 chromosomal integration (CIHHV-6) in Italian solid organ and allogeneic stem cell transplant patients.

The unique phenomenon of human herpesvirus-6 (HHV-6) chromosomal integration (CIHHV-6) may account for clinical drawbacks in transplant setting, being misinterpreted as active infection and leading to unnecessary and potentially harmful treatments. We have investigated the prevalence of CIHHV-6 in 205 consecutive solid organ (SO) and allogeneic stem cell transplant (alloSCT) Italian patients. Fifty-two (38.5%) of 135 solid organ transplant (SOT) and 16 (22.8%) of 70 alloSCT patients resulted positive for plasma HHV-6 DNA by real-time polymerase chain reaction. Seven SOT and three alloSCT patients presented HHV-6-related diseases, requiring antivirals. Two further patients (0.9%) were identified, presenting high HHV-6 loads. The quantification of HHV-6 on hair follicles disclosed the integrated state, allowing the discontinuation of antivirals. Before starting specific treatments, CIHHV-6 should be excluded in transplant patients with HHV-6 viremia by the comparison of HHV-6 loads on different fluids and tissues. Pretransplantation screening of donors and recipients may further prevent the misdiagnosis of CIHHV-6.

Evaluation of the Abbott Real-Time HIV-1 quantitative assay with dried blood spot specimens.

The Abbott Real-Time HIV-1 assay was evaluated for its performance in quantification of human immunodeficiency virus type 1 (HIV-1) RNA in dried blood spot (DBS) samples. In total, 169 blood samples with detectable plasma HIV-1 RNA were used to extract RNA from paired DBS and liquid plasma samples, using the automated Abbott m Sample Preparation System (m2000sp). HIV-1 RNA was then quantitated by the m2000rt RealTime analyser. RNA samples suitable for real-time PCR were obtained from all but one (99.4%) of the DBS samples and HIV-1 RNA was detected in 163/168 (97.0%) samples. The correlation between HIV-1 RNA values measured in paired DBS and plasma samples was very high (r = 0.882), with 78.5% and 99.4% of cases differing by <0.5 and 1.0 log, respectively. Retesting of DBS replicates following 6 months of storage at 2-8 degrees C showed no loss of HIV-1 RNA in a subset of 89 samples. The feasibility of DBS testing coupled with automated sample processing, and the use of a latest-generation FDA-approved real-time PCR-based system, represents an encouraging first step for viral load measurement in reference centres in developing countries where access to antiretroviral therapy is expanding.

First human case of Usutu virus neuroinvasive infection, Italy, August-September 2009.

We report the first worldwide case of Usutu virus (USUV) neuroinvasive infection in a patient with diffuse large B cell lymphoma who presented with fever and neurological symptoms and was diagnosed with meningoencephalitits. The cerebrospinal fluid was positive for USUV, and USUV was also demonstrated in serum and plasma samples by RT-PCR and sequencing. Partial sequences of the premembrane and NS5 regions of the viral genome were similar to the USUV Vienna and Budapest isolates.

Pharmacokinetic interaction between Amprenavir/Ritonavir and FosAmprenavir on cyclosporine in two patients with human immunodeficiency virus infection undergoing orthotopic liver transplantation.

The pharmacokinetic interaction between highly active antiretroviral therapy (HAART) and immunosuppressive drugs is a critical element in the management of patients with human immunodeficiency virus infection who undergo orthotopic liver transplantation (OLT). We describe the effect of the coadministration of Amprenavir/Ritonavir (APV/r) and FosAmprenavir (FosAPV) on cyclosporine (CsA) concentrations in two patients receiving OLT for end-stage liver disease due to hepatitis C Virus. Patient 1, who was maintained on 300 mg CsA twice a day with a trough concentration (C(trough)) around 250 ng/mL, restarted HAART 12 days after transplantation with 300 mg APV/r twice a day with corresponding APV C(trough) of 5293 ng/mL and RTV C(trough) of 186 ng/mL. Forty-eight hours after initiation of HAART, C(trough) of CsA was 1200 mg/mL, so it was necessary to reduce the CsA dosage 12-fold (50 mg every day) to achieve a therapeutic effect. In Patient 2, who was maintained on 300 mg CsA twice a day and a corresponding C(trough) of 400 ng/mL, HAART was restarted 12 days post-OLT with FosAPV 1400 mg twice a day. After 48 hours C(trough) of CsA was around 600 ng/mL and C(trough) of FosAPV, 1221 ng/mL. In this case it was necessary to reduce the CsA administration 3.5-fold (175 mg every day). In conclusion, therapeutic drug monitoring was necessary to monitor HAART and CsA post-OLT to prevent toxicity due to both therapies. The use of FosAPV without ritonavir boostering is sufficient to maintain adequate CsA blood concentrations, avoiding any event of toxicity.

Fatal cytomegalovirus necrotising enteritis in a small bowel transplantation adult recipient with low pp65 antigenaemia levels.

Although advances in immunosuppressive therapy have led to increased survival of solid organ transplantation recipients, it is well established that current protocols have been associated with an increased risk of developing tissue-invasive infections. In particular, cytomegalovirus still represents an important cause of morbidity. We report a case of cytomegalovirus infection involving the graft ileum with documented necrotising enteritis that developed after small bowel transplantation. The patient, a 56-year-old Caucasian female with a postsurgery short bowel syndrome, underwent a small bowel transplantation. Immunosuppression was maintained by combination of tacrolimus, steroids and daclizumab. Both the donor and the recipient were serologically negative for cytomegalovirus IgG. Nevertheless, ganciclovir prophylaxis was given for 21 days after surgery, as standard procedure. On hospital day 174, routine pp65 antigenaemia resulted positive (14/200,000 peripheral blood leukocytes). The patient was asymptomatic and preemptive ganciclovir therapy was instituted. In the following 3 days, due to a cytomegalovirus antigenaemia increase, ganciclovir was changed to foscarnet with subsequent virological response (7/200,000 peripheral blood leukocytes, on day 181). Two days later, the patient complained of acute abdominal pain and she underwent surgery for the diagnosis. Since the intraoperative findings consisted of a diffuse acute purulent peritonitis, the intestinal graft, together with native rectum, was removed. Biopsy specimens showed evidence of tissue-invasive cytomegalovirus infection. Postsurgery, the patient developed septic shock and died on day 198 as a consequence of multiple organ failure.

A simultaneous outbreak of Serratia marcescens and Klebsiella pneumoniae in a neonatal intensive care unit.

We describe two concurrent outbreaks of Serratia marcescens and Klebsiella pneumoniae in a neonatal intensive care unit (NICU). Over a 16-month period, a total of 27 infants were either colonized (N=14) or infected (N=13). There were 15 cases of S. marcescens and 11 cases of K. pneumoniae. Both micro-organisms were involved in one fatal case. Seven preterm babies developed septicaemia, two had bacteraemia, three had respiratory infections and one had purulent conjunctivitis. The S. marcescens and K. pneumoniae isolates were investigated by three molecular methods: enterobacterial repetitive intergenic consensus polymerase chain reaction (PCR), arbitrary primed PCR with M13 primer, and random amplification of polymorphic DNA. Different patterns were found in the 16 S. marcescens epidemic isolates from 16 newborn infants. The major epidemic-involved genotype was linked to the first nine cases and this was subsequently replaced by different patterns. Eight different typing profiles were also determined for the 13 K. pneumoniae isolates from 12 newborn infants. Four K. pneumoniae bacteraemic strains proved to be identical. In conclusion, the typing results revealed that two different micro-organisms (S. marcescens and K. pneumoniae) were simultaneously involved in invasive nosocomial infections in preterm newborns. Two simultaneous clusters of cases were documented. Heterogeneous genotypes among both species were also demonstrated to be present in the NICU at the same time. A focal source for both micro-organisms was not identified but cross-transmission through handling was probably an important route in this outbreak. Strict adherence to handwashing policies, cohorting, isolation of colonized and infected patients, and rigorous environmental hygiene were crucial measures in the containment of the epidemic.

Role of therapeutic drug monitoring in a patient with human immunodeficiency virus infection and end-stage liver disease undergoing orthotopic liver transplantation.

Pharmacological interactions between protease inhibitors and tacrolimus require careful monitoring to prevent toxicity in the posttransplantation period. A 42-year-old man with human immunodeficiency virus (HIV) infection and end-stage liver disease due to hepatitis C virus (HCV) received an orthotopic liver transplant. At the time of surgery the patient was on triple antiretroviral therapy (tenofovir, lamivudine, and lopinavir/ritonavir) with a stable CD4(+) count (>500 cells/mm(3)) and HIV-1 RNA (<50 copies/mL). Immunosuppression was maintained with tacrolimus (0.5 mg at a single dose once per week). One month after surgery HCV recurrence was documented. Pharmacokinetic evaluation of lopinavir/ritonavir showed a rapid increase in the area under the curve. Drug concentrations returned to normal levels, with reduction in liver enzymes. At the same time, tacrolimus dosages were reduced to a maintenance dose of 0.5 mg every 2 weeks. The patient, at 17 months postoperatively, is alive in good health with normal liver function and HCV RNA load levels. This is the first case in which a profound change in the pharmacokinetics of a protease inhibitor caused by a drug-drug interaction was observed during transient liver damage. Because this clinical event is particularly common in HIV-infected patients, our findings suggest that therapeutic drug monitoring should be performed to determine the impact of potential drug interactions in the early posttransplantation period, at the time of resumption of therapy or introduction of new anti-retroviral therapy and during HCV recurrence in order to optimize both tacrolimus and protease inhibitor treatment.

Rituximab as treatment of posttransplant lymphoproliferative disorder in patients who underwent small bowel/multivisceral transplantation: report of three cases.

This report describes three cases of posttransplant lymphoproliferative disorder (PTLD) in multivisceral/small bowel transplant patients treated with rituximab (anti-CD20 monoclonal antibodies). In two cases (one of which was a B-cell lymphoma) a good response to therapy was achieved. A third case (with polymorphic PTLD with low CD20 expression) developed a refractory rejection and PTLD was still documented on graftectomy. Rituximab was well tolerated, and a reduction of Epstein-Barr virus (EBV) viral load was documented by quantitive competitive-EBV polymerase chain reaction. Efficacy of therapy needs to be assessed in controlled studies.