Hepatitis C virus and proprotein convertase subtilisin/kexin type 9: a detrimental interaction to increase viral infectivity and disrupt lipid metabolism.

From viral binding to the hepatocyte surface to extracellular virion release, the replication cycle of the hepatitis C virus (HCV) intersects at various levels with lipid metabolism; this leads to a derangement of the lipid profile and to increased viral infectivity. Accumulating evidence supports the crucial regulatory role of proprotein convertase subtilisin/kexin type 9 (PCSK9) in lipoprotein metabolism. Notably, a complex interaction between HCV and PCSK9 has been documented. Indeed, either increased or reduced circulating PCSK9 levels have been observed in HCV patients; this discrepancy might be related to several confounders, including HCV genotype, human immunodeficiency virus (HIV) coinfection and the ambiguous HCV-mediated influence on PCSK9 transcription factors. On the other hand, PCSK9 may itself influence HCV infectivity, inasmuch as the expression of different hepatocyte surface entry proteins and receptors is regulated by PCSK9. The aim of this review is to summarize the current evidence about the complex interaction between HCV and liver lipoprotein metabolism, with a specific focus on PCSK9. The underlying assumption of this review is that the interconnections between HCV and PCSK9 may be central to explain viral infectivity.

Observed versus predicted cardiovascular events and all-cause death in HIV infection: a longitudinal cohort study.

BACKGROUND: The aim of the study was to assess the applicability of an algorithm predicting 10-year cardiovascular disease (CVD) generated in the setting of the Framingham Heart Study to a real-life, contemporary Italian cohort of HIV-positive subjects. METHODS: The study was an observational longitudinal cohort study. The probability for 10-year CVD events according to the Framingham algorithm was assessed in 369 consecutive HIV-positive participants free from overt CVD enrolled in 2004, who were followed for a median of 10.0 years (interquartile range, 9.1-10.1). Cardiovascular events included myocardial infarction, hospitalized heart failure, revascularized angina, sudden cardiac death, stroke, peripheral arterial disease. RESULTS: Over 3097 person-years of observation, we observed a total of 34 CVD events, whereas Framingham algorithm predicted the occurrence of 34.3 CVD events. CVD event rate was 11.0/1000 person-years of follow-up. In a receiver operating characteristics curve analysis, Framingham risk equation showed an excellent predictive value for incident CVD events (c-statistics, 0.83; 95% confidence interval, 0.76-0.90). In a multivariable Cox analysis, age, smoking and diabetes were independent predictors of CVD events. All-cause death rate was 20.0/1000 person-years of follow-up (n = 62 deaths). Causes of death included liver diseases (18), malignancies (14), AIDS-related (11); cardiovascular (9) and others (10). In a Cox analysis, age, AIDS diagnosis and chronic hepatitis were independent predictors of death. CONCLUSIONS: Observed CVD events in HIV-infected patients were well predicted by Framingham algorithm. Established major CVD risk factors are the strongest determinants of CVD morbidity in an Italian contemporary cohort of HIV-positive subjects. Interventions to modify traditional risk factors are urgently needed in HIV people.

Imported arboviral infections in Italy, July 2014-October 2015: a National Reference Laboratory report.

BACKGROUND: Imported cases of infections due to Dengue (DENV) and Chikungunya (CHIKV) viruses and, more recently, Zika virus (ZIKV) are commonly reported among travelers returning from endemic regions. In areas where potentially competent vectors are present, the risk of autochthonous transmission of these vector-borne pathogens is relatively high. Laboratory surveillance is crucial to rapidly detect imported cases in order to reduce the risk of transmission. This study describes the laboratory activity performed by the National Reference Laboratory for Arboviruses (NRLA) at the Italian National Institute of Health in the period from July 2014 to October 2015. METHODS: Samples from 180 patients visited/hospitalized with a suspected DENV/CHIKV/ZIKV infection were sent to the NRLA from several Italian Hospitals and from Regional Reference Laboratories for Arboviruses, in agreement with the National Plan on human surveillance of vector-borne diseases. Both serological (ELISA IgM test and Plaque Reduction Neutralization Test-PRNT) and molecular assays (Real Time PCR tests, RT-PCR plus nested PCR and sequencing of positive samples) were performed. RESULTS: DENV infection was the most frequently diagnosed (80 confirmed/probable cases), and all four genotypes were detected. However, an increase in imported CHIKV cases (41 confirmed/probable cases) was observed, along with the detection of the first ZIKV cases (4 confirmed cases), as a consequence of the recent spread of both CHIKV and ZIKV in the Americas. CONCLUSIONS: Main diagnostic issues highlighted in our study are sensitivity limitations of molecular tests, and the importance of PRNT to confirm serological results for differential diagnosis of Arboviruses. The continuous evaluation of diagnostic strategy, and the implementation of laboratories networks involved in surveillance activities is essential to ensure correct diagnosis, and to improve the preparedness for a rapid and proper identification of viral threats.

Monotherapy with darunavir/ritonavir or lopinavir/ritonavir versus standard antiretroviral therapy: a randomized clinical trial (2pm Study).

In a multicentre, open-label, clinical trial, 43 patients virologically suppressed while receiving a standard triple antiretroviral therapy were randomized (1:1:1) to switch to monotherapy with darunavir/ritonavir (DRV/r-MT arm), monotherapy with lopinavir/ritonavir (LPV/r-MT arm) or to continue on the ongoing regimen (cART arm). The proportion (95% CI) of patients with virological success (Snapshot analysis) at week 48 was 73% (48%-90%) in the DRV/r-MT arm, 69% (42%-88%) in the LPV/r-MT arm and 87% (61%-98%) in the cART arm. Virological failure was detected in only one patient receiving LPV/r-MT. The LPV/r-MT arm showed a modest worsening in lipid profile.

Efficacy of the CCR5 antagonist maraviroc in reducing early, ritonavir-induced atherogenesis and advanced plaque progression in mice.

BACKGROUND: CCR5 plays an important role in atherosclerosis and ischemic cardiovascular diseases, as well as in HIV replication and diffusion. HIV infection is characterized by a high burden of cardiovascular diseases, particularly in subjects exposed to ritonavir-boosted protease inhibitors. Maraviroc, a CCR5 antagonist antiretroviral drug, might provide benefit for patients with M-tropic HIV infections at high risk for cardiovascular diseases. METHODS AND RESULTS: Exposure to maraviroc limits the evolution and associated systemic inflammation of ritonavir-induced atherosclerotic in ApoE(-/-) mice and inhibits plaques development in a late model of atherosclerosis in which dyslipidemia plays the main pathogenic role. In ritonavir-treated mice, maraviroc reduced plaque areas and macrophage infiltration; downregulated the local expression of vascular cell adhesion molecule-1, intercellular adhesion molecule-1, monocyte chemoattractant protein-1, and interleukin-17A; and reduced tumor necrosis factor-α and RANTES (regulated on activation, normal T cell expressed, and secreted). Moreover, maraviroc counterregulated ritonavir-induced lipoatrophy and interlelukin-6 gene expression in epididymal fat, along with the splenic proinflammatory profile and expression of CD36 on blood monocytes. In the late model, maraviroc inhibited atherosclerotic progression by reducing macrophage infiltration and lowering the expression of adhesion molecules and RANTES inside the plaques. However, limited systemic inflammation was observed. CONCLUSIONS: In a mouse model of genetic dyslipidemia, maraviroc reduced the atherosclerotic progression by interfering with inflammatory cell recruitment into plaques. Moreover, in mice characterized by a general ritonavir-induced inflammation, maraviroc reversed the proinflammatory profile. Therefore, maraviroc could benefit HIV-positive patients with residual chronic inflammation who are at a high risk of acute coronary disease despite a suppressive antiretroviral therapy. To determine these benefits, large clinical studies are needed.

Highly active antiretroviral therapy-related mechanisms of endothelial and platelet function alterations.

Highly active antiretroviral therapy (HAART) has transformed human immunodeficiency virus (HIV) infection into a chronic condition, which has allowed the infected population to age and become prone to chronic degenerative diseases common to the general population, including atherosclerotic cardiovascular disease, and coronary artery disease (CAD). Possible causative mechanisms of HIV-associated CAD are related to classic cardiovascular risk factors, such as dyslipidemia, insulin resistance, and fat redistribution, which may be due to either HIV infection or to HAART-associated toxicity. However, other mechanisms are emerging as crucial for the cardiovascular complication of HIV and HAART. This article analyzes the effects of HIV and HAART on endothelial function, endothelium-leukocyte interactions, and platelets as possible mechanisms of enhanced cardiovascular risk.

Cerebrospinal fluid penetration of tigecycline.

We report, in a clinical setting, the tigecycline concentration and area under the concentration-time curve (AUC) - both in blood and in cerebrospinal fluid (CSF) - of a patient with a ventriculo-atrial shunt infection. Tigecycline weakly penetrates CSF the CSF-to-serum concentration ratio was 0.079 and CSF-to-serum AUC(0-12) ratio was 0.067.

Potential anti-inflammatory effects of maraviroc in HIV-positive patients: a pilot study of inflammation, endothelial dysfunction, and coagulation markers.

Persistent immune activation and chronic inflammation significantly contribute to non-AIDS morbidity in HIV-infected patients. The HIV inhibitor maraviroc (MVC) targets the cellular chemokine CCR5 HIV co-receptor, which is involved in important inflammatory pathways. MVC could have significant anti-inflammatory and anti-atherosclerotic effects, also reducing immune activation. We designed a pilot study to determine which plasma biomarkers of inflammation, endothelial dysfunction, and hypercoagulability were modified by MVC in 2 groups of 10 patients starting MVC-free or MVC-containing regimens. Ten age- and gender-matched healthy controls were also included. We found higher levels of all inflammatory biomarkers in HIV-infected patients compared to healthy controls. Both groups showed decreasing levels of interleukin (IL)-17, IL-10, and macrophage inflammatory protein (MIP)-1a following the achievement of viral suppression. Vascular cell adhesion molecule (VCAM)-1 levels were decreased in the MVC group and increased in the MVC-free group. In conclusion, some inflammatory biomarkers tend to decrease with the salvage regimen; MVC was not associated with a better impact on these measured markers.

Glucocorticoid receptor mediates the gluconeogenic activity of the farnesoid X receptor in the fasting condition.

The glucocorticoid receptor (GR) is a master gene orchestrating the activation of gluconeogenic genes in the liver in response to food withdrawal. Mechanisms of GR regulation by other nuclear receptors, however, are poorly defined. Here, we report that the farnesoid X receptor (FXR), a bile acid sensor, activates gluconeogenic pathways in the liver and regulates GR expression and activity. FXR-null mice are hypoglycemic in the unfed state and exhibit both a reduced hepatic production of glucose in response to the pyruvate challenge and a decreased expression of two rate-limiting enzymes involved in gluconeogenesis, phosphoenolpyruvate carboxykinase (PEPCK), and glucose-6-phosphatase (G6Pase), along with blunted liver expression of GR. Treating wild-type mice with a semisynthetic FXR ligand (6E-CDCA) increases the liver expression of GR, PEPCK, and G6Pase. This effect was lost in fed animals, as well as in FXR(-/-) mice. The human and mouse GR promoters contain a conserved FXR-responsive element (an ER-8 sequence) whose activation by FXR ligation leads to GR transcription. GR silencing by siRNA in vitro or its pharmacological antagonism in vivo with mifepristone reverses the effect of FXR activation on expression of gluconeogenic genes. These findings demonstrate that an FXR-GR pathway regulates the activation of hepatic gluconeogenesis in the transition from the unfed to the fed state.

Syphilis as a diagnosis of liver abnormalities in HIV.

In order to investigate syphilitic liver involvement in HIV-infected patients, a single-centre retrospective study of a cohort of HIV-infected patients with syphilis was performed at the Infectious Diseases Clinic of Perugia, Italy, between December 2002 and March 2010. Fifty HIV-infected patients were identified with syphilis plus baseline and follow-up liver tests. The following syphilis diagnoses were recorded: 19 secondary (38%), 26 latent (52%), and 5 tertiary/neurosyphilis (12%). Syphilitic hepatitis was found in 5/50 (10%) patients. This finding supports the importance of including syphilis in the differential diagnosis of liver enzyme abnormalities in HIV-infected patients. An early diagnosis of syphilitic hepatitis can lead to rapid normalization of liver function following appropriate therapy, prevents the progression of syphilis, and limits the further spread of sexually transmitted diseases, including HIV.

Stroke in patients with tuberculous meningitis in a low TB endemic country: an increasing medical emergency?

Stroke due to brain vascular disease is a serious complication of tuberculous meningitis (TBM). This study evaluated the frequency, clinical characteristics, risk factors and outcomes of patients with TBM complicated by stroke admitted to the Infectious Disease Clinic, University of Perugia Hospital, Italy from 1971 to 2010. Over four decades, 419 patients were admitted with tuberculosis, of these 30 (7.1%) were diagnosed with TBM: 20 definite, one probable and nine possible. Twenty-six were evaluable for stroke and six (23%) had stroke. The latter six had advanced stages of meningitis, two tested HIV positive, three HIV negative and in one HIV was not performed. Of seven patients without stroke tested for HIV, only one resulted positive. No differences were found regarding CSF cell count, sugar, protein, microscopy or growth of Mycobacterium tuberculosis among patients with or without stroke. The overall survival rate at discharge was 83% in patients with stroke and 95% in those without stroke. It was found that stroke can be frequent among patients with TBM and the presence of HIV infection might be associated with a higher rate of stroke. Further research is needed on these findings, especially in low TB endemic countries.

HIV-1 infection is associated with changes in nuclear receptor transcriptome, pro-inflammatory and lipid profile of monocytes.

BACKGROUND: Persistent residual immune activation and lipid dysmetabolism are characteristics of HIV positive patients receiving an highly active antiretroviral therapy (HAART). Nuclear Receptors are transcription factors involved in the regulation of immune and metabolic functions through the modulation of gene transcription. The objective of the present study was to investigate for the relative abundance of members of the nuclear receptor family in monocytic cells isolated from HIV positive patients treated or not treated with HAART. METHODS: Monocytes isolated from peripheral blood mononuclear cells (PBMC) were used for analysis of the relative mRNA expressions of FXR, PXR, LXR, VDR, RARα, RXR, PPARα, PPARß, PPARγ and GR by Real-Time polymerase chain reaction (PCR). The expression of a selected subset of inflammatory and metabolic genes MCP-1, ICAM-1, CD36 and ABCA1 was also measured. RESULTS: Monocytes isolated from HIV infected patients expressed an altered pattern of nuclear receptors characterized by a profound reduction in the expressions of FXR, PXR, PPARα, GR, RARα and RXR. Of interest, the deregulated expression of nuclear receptors was not restored under HAART and was linked to an altered expression of genes which supports both an immune activation and altered lipid metabolism in monocytes. CONCLUSIONS: Altered expression of genes mediating reciprocal regulation of lipid metabolism and immune function in monocytes occurs in HIV. The present findings provide a mechanistic explanation for immune activation and lipid dysmetabolism occurring in HIV infected patients and could lead to the identification of novel potential therapeutic targets.

Achromobacter denitrificans renal abscess.

We describe a case of a 66-year-old immunocompetent man affected by Achromobacter denitrificans renal abscess related to renal stones. The patient was treated successfully with meropenem 1 g three times daily for 60 days. To our knowledge, this is the first ever case reported of Achromobacter denitrificans renal abscess.

Lingual tuberculosis: a rare disease in Western countries.

Here we report on two consecutive cases of tuberculosis in immunocompetent HIV-negative patients with lingual lesions. In both patients diagnosis was delayed. Disease progressed involving the lungs, lymph nodes and also the brain. Both patients are disease-free at 30 and 22 month follow-up respectively. Isolated Mycobacterium tuberculosis from these patients was multi-susceptible. Tuberculosis lesions of the oral cavity and brain are infrequently diagnosed in immunocompetent subjects from Western countries. Clinicians must take into greater consideration tuberculosis as a possible diagnosis when diagnosing chronic and/or recurrent lingual lesions even in the absence of pulmonary lesions.

A giant pancreatic pseudocyst in a patient with HIV infection.

This article describes the first case of a giant pancreatic pseudocyst in a 48-year-old man with HIV infection under combination antiretroviral therapy. The patient presented with an abdominal mass involving the epigastrium, left hypochondrium, and left flank. An enhanced abdominal computed tomography (CT) scan showed a well-defined cyst of 21 cm in diameter, with a liquid content that dislocated adjacent viscera. Microbiological and cytological tests on fluid were negative, confirming diagnosis of pancreatic pseudocyst. The CT-guided percutaneous drainage was carried out and the patient's clinical condition gradually improved.

Bactericidal activity of oxacillin and glycopeptides against Staphylococcus aureus in patients with endocarditis: looking for a relationship between tolerance and outcome.

BACKGROUND: There is no clear relationship between in vitro bactericidal activity tests and clinical outcome. We studied bactericidal activity of oxacillin, vancomycin and teicoplanin against Staphylococcus aureus isolates in patients with endocarditis and then we sought to determine if there was a relationship between in vitro bactericidal activity and clinical outcome. METHODS: Minimal bacteriostatic and minimal bactericidal concentrations were determined for Staphylococcus aureus strains isolated from patients with endocarditis following standardized methods. Medical records were reviewed retrospectively to collect data on antimicrobial susceptibility at admission, antimicrobial therapy, need for surgery, embolic events and outcome. RESULTS AND DISCUSSION: Sixty-two Staphylococcus aureus strains were studied in 62 patients with endocarditis. Overall, 91.9% definite, 21% methicillin resistant and 72.6% cured. Surgery was performed in 32.3% and embolic events were documented in 64.5%. Tolerance to oxacillin and teicoplanin was more common than vancomycin tolerance among methicillin susceptible Staphylococcus aureus. Among methicillin resistant Staphylococcus aureus teicoplanin was shown to have a higher rate of tolerance than vancomycin. No statistically significant differences on clinical outcome between oxacillin tolerant and oxacillin non tolerant Staphylococcus aureus infections were observed. Tolerance to oxacillin did not adversely affect clinical outcomes of patients with methicillin susceptible Staphylococcus aureus endocarditis treated with a combination of antimicrobials including oxacillin. The cure rate was significantly lower among patients with methicillin resistant Staphylococcus aureus endocarditis. CONCLUSIONS: In vitro bactericidal test results were not valid predictors of clinical outcome. Physicians need to use additional parameters when treating patients with staphylococcal endocarditis.

Diagnosing tuberculosis in pregnancy: a case report.

A case of miliary tuberculosis complicated by deciduitis and sub-chorionitis in a pregnant woman manifesting also influenza A/H1N1v infection and urinary tract infection is reported. Diagnosis of tuberculosis was obtained before delivery by examining amniotic fluid for Mycobacterium tuberculosis. Even though maternal symptoms did not suggest TB, diagnosis was early enough to start effective treatment in both the mother and the neonate and prevent in-hospital M.tuberculosis diffusion. A high index of suspicion by health professionals is required to detect and manage tuberculosis in pregnancy and newborns in both the developed and developing word.