Successful Treatment of Aortic Endocarditis by Achromobacter xylosoxidans with Cefiderocol Combination Therapy in a Non-Hodgkin Lymphoma Patient: Case Report and Literature Review.

Achromobacter xylosoxidans is a Gram-negative aerobic opportunistic bacterium, belonging to the order of Burkholderiales, that can cause infections of virtually all body districts in patients with underlying diseases. However, A. xylosoxidans has rarely been associated with infective endocarditis. The treatment of A. xylosoxidans infections is complicated by both intrinsic and acquired resistance. Here we report on a case of aortic endocarditis by A. xylosoxidans in a Non-Hodgkin lymphoma patient treated with a combination of cefiderocol and other antibiotics, and summarize the available literature.

Inflammation and microbial translocation measured prior to combination antiretroviral therapy (cART) and long-term probability of clinical progression in people living with HIV.

BACKGROUND: Despite the effectiveness of cART, people living with HIV still experience an increased risk of serious non-AIDS events, as compared to the HIV negative population. Whether pre-cART microbial translocation (MT) and systemic inflammation might predict morbidity/mortality during suppressive cART, independently of other known risk factors, is still unclear. Thus, we aimed to investigate the role of pre-cART inflammation and MT as predictors of clinical progression in HIV+ patients enrolled in the Icona Foundation Study Cohort. METHODS: We included Icona patients with ≥2 vials of plasma stored within 6 months before cART initiation and at least one CD4 count after therapy available. Circulating biomarker: LPS, sCD14, EndoCab, hs-CRP. Kaplan-Meier curves and Cox regression models were used. We defined the endpoint of clinical progression as the occurrence of a new AIDS-defining condition, severe non-AIDS condition (SNAEs) or death whichever occurred first. Follow-up accrued from the data of starting cART and was censored at the time of last available clinical visit. Biomarkers were evaluated as both binary (above/below median) and continuous variables (logescale). RESULTS: We studied 486 patients with 125 clinical events: 39 (31%) AIDS, 66 (53%) SNAEs and 20 (16%) deaths. Among the analyzed MT and pro-inflammatory markers, hs-CRP seemed to be the only biomarker retaining some association with the endpoint of clinical progression (i.e. AIDS/SNAEs/death) after adjustment for confounders, both when the study population was stratified according to the median of the distribution (1.51 mg/L) and when the study population was stratified according to the 33% percentiles of the distribution (low 0.0-1.1 mg/L; intermediate 1.2-5.3 mg/L; high > 5.3 mg/L). In particular, the higher the hs-CRP values, the higher the risk of clinical progression (p = 0.056 for median-based model; p = 0.002 for 33% percentile-based model). CONCLUSIONS: Our data carries evidence for an association between the risk of disease progression after cART initiation and circulating pre-cART hs-CRP levels but not with levels of MT. These results suggest that pre-therapy HIV-driven pro-inflammatory milieu might overweight MT and its downstream immune-activation.

Results from a survey in healthy blood donors in South Eastern Italy indicate that we are far away from herd immunity to SARS-CoV-2.

Here we present results from a survey on anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) seroprevalence in healthy blood donors from a low incidence coronavirus disease 2019 area (Apulia region, South Eastern Italy). Among 904 subjects tested, only in nine cases (0.99%) antibodies against SARS-CoV-2 were demonstrated. All the nine seropositive patients were negative for the research of viral RNA by reverse transcription polymerase chain reaction in nasopharyngeal swabs. These data, along with those recently reported from other countries, clearly show that we are very far from herd immunity and that the containment measures are at the moment the only realistic instrument we have to slow the spread of the pandemic.

Sterol metabolism modulates susceptibility to HIV-1 Infection.

BACKGROUND: 25-hydroxylase (CH25H) is an interferon-stimulated gene (ISG), which catalyzes the synthesis of 25-hydroxycholesterol (25HC). 25HC intervenes in metabolic and infectious processes and controls cholesterol homeostasis and influences viral entry into host cells. We verified whether natural resistance to HIV-1 infection in HIV-1-exposed seronegative (HESN) individuals is at least partially mediated by particularities in sterol biosynthesis. METHODS: Peripheral blood mononuclear cells (PBMCs) and monocyte-derived macrophages (MDMs) isolated from 15 sexually exposed HESN and 15 healthy controls were in vitro HIV-1-infected and analyzed for: percentage of IFNα-producing plasmacytoid dendritic cells (pDCs); cholesterol signaling and inflammatory response RNA expression; resistance to HIV-1 infection. MDMs from five healthy controls were in vitro HIV-1-infected in the absence/presence of exogenously added 25HC. RESULTS: IFNα-producing pDCs were augmented in HESN compared with healthy controls both in unstimulated and in in vitro HIV-1-infected PBMCs (P < 0.001). An increased expression of CH25H and of a number of genes involved in cholesterol metabolism (ABCA1, ABCG1, CYP7B1, LXRα, OSBP, PPARγ, SCARB1) was observed as well; this, was associated with a reduced susceptibility to in-vitro HIV-1-infection of PBMCs and MDMs (P < 0.01). Notably, addition of 25HC to MDMs resulted in increased cholesterol efflux and augmented resistance to in-vitro HIV-1-infection. CONCLUSION: Results herein show that in HESN sterol metabolism might be particularly efficient. This could be related to the activation of the IFNα pathway and results into a reduced susceptibility to in-vitro HIV-1 infection. These results suggest a possible basis for therapeutic interventions to modulate HIV-1 infection.

Genetic variability at the TREX1 locus is not associated with natural resistance to HIV-1 infection.

Three prime repair exonuclease 1 (TREX1) degrades excess HIV-1 DNA, thereby preventing recognition by innate immunity receptors and type I interferon responses. Analyses performed in two HIV-exposed seronegative (HESN) cohorts did not show any differences in TREX1 sequence, single nucleotide polymorphisms frequency, or expression in HESN compared to controls, suggesting that, despite its central role in the HIV-1 infection process, genetic diversity at TREX1 is not a major determinant of susceptibility to infection in humans.

A positively selected APOBEC3H haplotype is associated with natural resistance to HIV-1 infection.

APOBEC3 genes encode cytidine deaminases endowed with the ability to inhibit retroviruses and retrotransposons. These genes have been targets of natural selection throughout primate evolutionary history. We analyzed their selection pattern in human populations observing that APOBEC3F and 3G are neutrally evolving. Conversely, nucleotide diversity was extremely high for APOBEC3H, and most tests rejected the hypothesis of selective neutrality in Eurasian populations. Haplotype analysis and the derived intraallelic nucleotide diversity test indicated that positive selection has driven the increase in frequency of one haplotype (Hap I) outside Africa. Consistently, population genetic differentiation between African and non-African populations was higher than expected under neutrality. A case-control association analysis indicated that Hap I is associated with protection from sexually transmitted HIV-1 infection. Hap I carries a protein-destabilizing variant and a residue conferring resistance to Vif-mediated degradation. Data herein suggest that lower protein stability might have been traded-off with a higher ability to circumvent Vif-mediated hijacking. Alternatively, transcription regulatory variants might represent the selection target. Our data represent an example of how the selective pressures exerted by extinct or unknown viral agents can be exploited to provide valuable information on the allelic determinants of susceptibility to modern infections.

Risk of developing specific AIDS-defining illnesses in patients coinfected with HIV and hepatitis C virus with or without liver cirrhosis.

BACKGROUND: There are few data concerning the risk of specific opportunistic diseases in patients with and without hepatitis C virus (HCV) infection. We evaluated the correlation between the occurrence of different AIDS-defining illnesses (ADIs) and chronic HCV infection or HCV-related liver cirrhosis in a large Italian cohort of human immunodeficiency virus (HIV)-infected subjects. METHODS: Subjects were stratified into 2 groups: patients without HCV coinfection and with persistently normal aminotransferase levels and patients with HCV coinfection. The patients with HCV coinfection were stratified according to the diagnosis of liver cirrhosis. The incidences of new ADIs were calculated as the number of events per 1000 person-years of follow-up. The rates in the 2 groups were compared using a Poisson regression model adjusted for potential confounders. RESULTS: We observed a total of 496 ADIs among 5397 patients with 25,105 person-years of follow-up (50% tested positive for HCV). HCV coinfection was associated with increased risk of developing an ADI (adjusted relative rate [ARR], 2.61; 95% confidence interval [CI], 1.88-3.61), specifically bacterial infection (ARR, 3.15; 95% CI, 1.76-5.67), HIV-related disease (ARR, 2.68; 95% CI, 1.03-6.97), and mycotic disease (ARR, 3.87; 95% CI, 2.28-6.59) but not non-Hodgkin lymphoma (ARR, 0.88; 95% CI, 0.22-3.48). The rate of mycotic infection, bacterial infection, toxoplasmosis, and HIV-related ADI among patients with cirrhosis were significantly higher than that among HIV-monoinfected patients, and the risk was greater than that estimated for HCV antibody-positive patients without cirrhosis. CONCLUSIONS: HIV-related bacterial and mycotic infections are strongly associated with positive HCV serostatus and HCV-related cirrhosis. Clinicians should take into account these data when making decisions on initiation of antiretroviral therapy for HCV-coinfected individuals.

Specific enfuvirtide-associated mutational pathways in HIV-1 Gp41 are significantly correlated with an increase in CD4(+) cell count, despite virological failure.

BACKGROUND: Human immunodeficiency virus type 1 (HIV-1) gp41 is a crucial determinant for HIV-1 pathogenicity. We investigated the correlation of enfuvirtide (ENF)-associated gp41 mutational clusters with viroimmunological parameters, as well as the potential underlying mechanisms. METHODS: A total of 172 gp41 sequences and clinical follow-up data from 73 ENF-treated patients were analyzed monthly, from baseline to week 48. RESULTS: There were 7 novel gp41 mutations positively associated with ENF treatment and correlated with classic ENF mutations. The ENF-associated clusters [V38A + N140I ] and [V 38A +T18A ] significantly correlated with an increase in CD4 cell count at week 48 ( an increase from baseline of 112 and 209 cells/microL, respectively), whereas [Q40H + L45M + 268A] significantly correlated with a decrease in CD4 cell count (-53 cells/microL), without a change in the level of viremia. Residues 38 and 18 are located complementarily to each other in the Rev-responsive element, whereas analysis of molecular dynamics showed that the copresence of [V38A + N140 I] abolishes the interaction between residue 38 and 145 important for stabilization of the 6-helix bundle. In contrast, T268A localizes in the gp41 calmodulin-binding domain responsible for gp41-induced CD4(+) T lymphocyte apoptosis. CONCLUSION: Specific gp41 mutational clusters associated with ENF treatment significantly correlate with increases in CD4(+) cell count. Structural analysis suggests that this immunological gain is associated with mechanisms that act at both the protein level and the RNA level (even under conditions of virological failure). This result may help in the selection of patients who can benefit most from ENF treatment and represents a driving force for the design of the next generation of entry inhibitors.

Influence of viral chronic hepatitis co-infection on plasma drug concentrations and liver transaminase elevations upon therapy switch in HIV-positive patients.

It is still controversial whether viral hepatitis co-infection can influence antiretroviral plasma drug concentrations and whether drug concentrations are correlated with liver enzyme elevations during highly active antiretroviral therapy. An analysis of data from a cohort of 220 human immunodeficiency virus (HIV)-infected patients was conducted. Univariate and multivariate logistic analyses were performed to identify predictors of plasma drug concentrations. The association of transaminase elevation with higher plasma drug concentrations was explored following stratification of patients into HIV monoinfected and hepatitis C virus (HCV) and/or hepatitis B virus (HBV) co-infected groups. Hepatitis co-infections were independently correlated with drug concentrations above the therapeutic cut-offs at Week 1 (P=0.06), Week 4 (P=0.04) and Week 12 (P=0.005). The apparent effect was independent of the possible impact exerted by other variables such as demographics and medication adherence. The incidence of relevant hypertransaminasaemia was low. Patients with hepatitis co-infections had higher rates of transaminase elevation than monoinfected HIV patients; however, risk of transaminase elevation was not associated with drug concentrations. The presence of HCV and/or HBV co-infections correlated with higher plasma drug concentrations, although it did not appear to influence hepatotoxicity risk.

Specific mutations in HIV-1 gp41 are associated with immunological success in HIV-1-infected patients receiving enfuvirtide treatment.

OBJECTIVES: To investigate gp41 variability and correlation with viro-immunological parameters in 54 HIV-1-infected patients receiving enfuvirtide added as single active drug to a failing regimen. METHODS: One hundred and two HIV-1 gp41 sequences and clinical follow-up from 54 enfuvirtide-treated patients were analysed from baseline to week 36 of treatment. The association of mutations with viraemia/CD4 count was assessed by Mann-Whitney test. RESULTS: The addition of enfuvirtide to the failing regimen induced at week 4 a viraemia decrease from 5.1 to 4.3 log(10)/mL (P = 0.0002) and a CD4 increase from 48 to 106 cells/mm(3) (P = 0.008). While viraemia rebounded to 4.8 and 4.6 log(10)/mL at week 12 and 36, respectively, CD4 continued to increase to 136 cells/mm(3) at week 36. Enfuvirtide resistance mutations, rarely found at baseline, occurred in 45/54 (83.3%) enfuvirtide-treated patients. V38A/E were the most represented mutations at all time-points. The presence of V38A/E was significantly associated with a 4.5-fold CD4 increase from baseline to week 24 and with a 6-fold increase at week 36 (P = 0.004 and 0.02 compared without V38A/E, respectively), without significant correlation with viraemia. In contrast, Q40H + L45M (present in six enfuvirtide-treated patients at week 36) correlated with CD4 loss from baseline to week 36 (P = 0.02), without significant correlation with viraemia. Mutation N126K (observed in six enfuvirtide-treated patients, never found at baseline) abrogates the fourth gp41 glycosylation site and correlates with a 2.1-fold CD4 increase at week 24. CONCLUSIONS: Specific enfuvirtide resistance mutations (V38A/E) are associated with a sustained CD4 increase, without remarkable effects upon viraemia. This CD4 recovery, due to virus- and immune-mediated mechanisms most probably not applicable to protease/reverse transcriptase inhibitors, is important for innovative therapeutic strategies.

Influence of genotype 3 hepatitis C coinfection on liver enzyme elevation in HIV-1-positive patients after commencement of a new highly active antiretroviral regimen: results from the EPOKA-MASTER Cohort.

BACKGROUND: The independent role of hepatitis C virus (HCV) genotype 3 in liver transaminase elevation following highly active antiretroviral regimens is still controversial. METHODS: Analysis of data from a cohort of 492 HIV/HCV-coinfected patients was conducted using an intention-to-treat approach. Incidence of grade > or = III liver transaminase elevation was estimated per 100 patient-years of follow-up. Univariate and multiple proportional hazards regression analysis of factors that may predict liver enzyme elevation was performed. RESULTS: The incidence of grade > or = III hepatotoxicity was 25 per 100 patient-years among patients coinfected with HCV genotype 3 and 11 per 100 patient-years among those with other genotypes. On multiple proportional hazard regression analysis, time-to-grade > or = III liver enzyme elevation was directly correlated with HCV genotype 3 (hazards ratio [HR]: 2.0, 95% CI: 1.3 to 2.9; P = 0.001), male gender (HR: 2.7; 95% CI: 1.3 to 5.7; P = 0.007), chronic hepatitis B virus infection (HR: 2.9, 95% CI: 1.5 to 5.9; P = 0.002), and alanine aminotransferase level at baseline (per 10 IU/L HR: 1.10; 95% CI: 1.06 to 1.15; P < 0.001). In the same model, higher CD4 T-cell counts at baseline were inversely correlated with risk of hepatotoxicity (HR: 0.998; 95% CI: 0.997 to 0.999; P = 0.036). Moreover, among patients experienced to antiretroviral drugs, previous grade > or = III hepatotoxicity (HR: 2.8; 95% CI: 1.8 to 4.3; P < 0.001) was an adjunctive independent risk factor. CONCLUSIONS: HIV-positive patients coinfected with HCV genotype 3 displayed a higher risk of relevant hepatotoxicity, independently from other clinical variables. The impact of HCV genotype outweighed the role of drugs in determining hepatotoxicity.

Genotypes at chromosome 22q12-13 are associated with HIV-1-exposed but uninfected status in Italians.

OBJECTIVE: Despite multiple and repeated exposures to HIV-1, some individuals possess no detectable HIV genome and show T-cell memory responses to the viral antigens. HIV-1-reactive mucosal IgA detected in such uninfected individuals suggests their possible immune resistance against HIV. We tested if the above HIV-1-exposed but uninfected status was associated with genetic markers other than a homozygous deletion of the CCR5 gene. METHODS: Based on our mapping in chromosome 15 of a gene controlling the production of neutralizing antibodies in a mouse retrovirus infection, we genotyped 42 HIV-1-exposed but uninfected Italians at polymorphic loci in the syntenic segment of human chromosome 22, and compared them with 49 HIV-1-infected and 47 uninfected healthy control individuals by a closed testing procedure. RESULTS: A significant association was found between chromosome 22q12-13 genotypes and a putative dominant locus conferring anti-HIV-1 immune responses in the exposed but uninfected individuals. Distributions of linkage disequilibrium across chromosome 22 also differed between the exposed but uninfected and two other phenotypic groups. CONCLUSIONS: The data indicated the presence of a new genetic factor associated with the HIV-1-exposed but uninfected status.

Human alpha defensin in HIV-exposed but uninfected individuals.

Human alpha defensins 1, 2, and 3 are produced by CD8 T cells of HIV-infected long-term nonprogressors and have an antiviral activity. alpha Defensins were examined in peripheral blood mononuclear cells (PBMCs), cervical-vaginal mononuclear cells (CVMCs), and cervical biopsies of 9 HIV-1-exposed but uninfected women (ESNs), 10 HIV-infected patients (HIV), and 13 low-risk healthy controls (HCs). Results showed that, whereas alpha defensin production and alpha defensin-expressing CD8 lymphocytes were comparable in ESNs and HIV patients, constitutive alpha defensin production by peripheral CD8 and CVMCs was augmented in ESNs compared with HCs (P = 0.001 and P = 0.058, respectively); alpha defensin mRNA was increased in PBMCs of ESNs; unstimulated, alpha defensin-expressing peripheral and mucosal CD8 lymphocytes were 10-fold higher in ESNs compared with HCs (P = 0.003 and P = 0.01, respectively); and alpha defensin mRNA and alpha defensin-expressing cells were augmented in cervical biopsies of ESN compared with HCs (mRNA:P = 0.03). The differences were reduced upon in vitro mitogen stimulation. A robust constitutive production of alpha defensin is seen in HIV-exposed uninfected individuals; these peptides could have a role in the potentially protective immune response that characterizes ESNs.