Detection of HIV-1 matrix protein p17 in sera of viremic and aviremic patients

People living with human immunodeficiency virus type 1 (HIV-1), even if successfully treated with a combined antiretroviral therapy, display a persistent inflammation and chronic immune activation, and an increasing risk of developing cardiovascular and thrombotic events, cancers, and neurologic disorders. Accumulating evidence reveals that biologically active HIV-1 proteins may play a role in the development of these HIV-1-associated conditions. The HIV-1 matrix protein p17 (p17) is released and accumulates in different organs and tissue where it may exert multiple biological activities on different target cells. To assess a role of p17 in different HIV-1-related pathological processes, it is central to definitively ascertain and quantitate its expression in a large number of sera obtained from HIV-1-infected (HIV-1+) patients. To this aim, we developed a specific and highly sensitive p17 capture immunoenzymatic assay. Data obtained highlight a heterogeneous expression of p17 in blood of tested patients, with patients who were negative or displayed from low to relatively high p17 blood concentrations (range from 0.05 to 7.29 nM). Moreover, we found that blood p17 concentration was totally independent from the viremic status of the patient. This finding calls for monitoring HIV-1+ patients in order to evaluate a possible correlation between p17 amount in blood and the likelihood of developing HIV-1-related pathological conditions.

Genome-wide association studies of response and side effects to the BNT162b2 vaccine in Italian healthcare workers: Increased antibody levels and side effects in carriers of the HLA-A*03:01 allele

The remarkable variability of response to vaccines against SARS-CoV-2 is apparent. The present study aims to estimate the extent to which the host genetic background contributes to this variability in terms of immune response and side effects following the administration of the BNT162b2 vaccine. We carried out a genome wide association study (GWAS) by genotyping 873 Italian healthcare workers who underwent anti-SARS-CoV-2 vaccination with the BNT162b2 vaccine and for whom information about anti-SARS-CoV-2 spike antibodies titers and vaccine side effects were available. The GWAS revealed a significant association between the HLA locus and the anti-SARS-CoV-2 Spike antibodies level at 2 months following the first dose of vaccine (SNP: rs1737060; p = 9.80 × 10-11 ). In particular, we observed a positive association between the antibody levels and the presence of the HLA-A*03:01 allele. The same allele was found associated with a 2-2.4-fold increased risk of experiencing specific side effects such as fever, chills and myalgia and a 1.5-1.8-fold increased risk of joint pain, nausea, fatigue, headache and asthenia, independently of age and sex. This study confirms that the heterogeneity in the immune response to the BNT162b2 vaccine and in its side effects are at least partially influenced by genetic variants. This information, integrated with individual biological and lifestyle-related correlates, could be of use in the definition of algorithms aimed at the identification of subjects in which the administration of additional vaccine doses would be particularly beneficial to maintain immunity against the virus.

Traceability of SARS-CoV-2 transmission through quasispecies analysis

During COVID-19 pandemic, consensus genomic sequences were used for rapidly monitor the spread of the virus worldwide. However, less attention was paid to intrahost genetic diversity. In fact, in the infected host, SARS-CoV-2 consists in an ensemble of replicating and closely related viral variants so-called quasispecies. Here we show that intrahost single nucleotide variants (iSNVs) represent a target for contact tracing analysis. Our data indicate that in the acute phase of infection, in highly likely transmission links, the number of viral particles transmitted from one host to another (bottleneck size) is large enough to propagate iSNVs among individuals. Furthermore, we demonstrate that, during SARS-CoV-2 outbreaks when the consensus sequences are identical, it is possible to reconstruct the transmission chains by genomic investigations of iSNVs. Specifically, we found that it is possible to identify transmission chains by limiting the analysis of iSNVs to only three well-conserved genes, namely nsp2, ORF3, and ORF7.

Timing and implications for immune response to vaccine in SARS-CoV-2 breakthrough infections

COVID-19 vaccines elicit a strong anti-S antibodies response. We aim to describe antibody titers in peri-vaccination SARS-CoV-2 infections. This is a retrospective longitudinal single-cohort study. Serological tests were performed at the time of the first SARS-CoV-2 vaccine dose (T0) and 60 (T1), 120 (T2), and 240 (T3) days after. The study included 4,682 subjects. Group A had the infection without an anti-S Ig response. Group B and C seroconverted for anti-N Ig between T0 and T1 and between T1 and T2, respectively. Group D was persistently anti-N Ig negative. Group B showed an initial sub-optimal response, reaching the highest titer at T3. Those who received the second dose 120 days after the infection had higher titers compared to those who received it 21 days after the first dose. The immune response depends on the number and the timing of vaccine doses, highlighting the need for a more personalized approach to vaccination.

The Effect of the Immunization Schedule and Antibody Levels (Anti-S) on the Risk of SARS-CoV-2 Infection in a Large Cohort of Healthcare Workers in Northern Italy

Given their occupational risk profile, HCWs were the first to receive anti-SARS-CoV-2 vaccination. However, breakthrough infections remained common, mainly sustained by new SARS-CoV-2 variants of concern (VOCs) that rapidly spread one after another in Italy. Evidence suggests that the measured level of anti-SARS-CoV-2 antibodies does not clearly predict the level of protection conferred by either natural infection or vaccine-induced immunization, highlighting the need for further study on the diversity in susceptibility to SARS-CoV-2 infection. The present study aimed to characterize different risk profiles for SARS-CoV-2 infection in HCWs who had recently received the booster dose, and who were classified according to their immunization profile. The very small number of workers infected during the 8 months following the primary-cycle administration represents proof of the vaccine’s effectiveness against non-omicron strains. The comparison among different immunization profiles showed that hybrid immunization (vaccine plus natural infection) elicits higher antibody levels. However, hybrid immunization does not always provide better protection against reinfection, thus suggesting that the immunization profile plays a major role as a virus–host interaction modifier. Despite the high resistance to the reinfection, the peri-booster infection had a not-neglectable infection rate (5.6%), this further reinforcing the importance of preventive measures.

Immune Responses to SARS-CoV-2 Infection and Vaccine in a Big Italian COVID-19 Hospital: An 18-Month Follow-Up

OBJECTIVES

This is a longitudinal prospective study which was designed to assess the trend of anti-SARS-CoV-2 antibodies targeting the Spike (anti-S) and Nucleocapside protein (anti-N) viral antigens over a 9-month period after the administration of an anti-SARS-CoV-2 vaccine in a big COVID-19 hospital located in Northern Italy.

PARTICIPANTS

7411 vaccinated workers were included in a linear mixed-effect model analysis performed to model the anti-S decay over the 9 months following the vaccination, during serological screening performed approximately 2, 4, and 9 months following the first jab administration. Serological tests performed in the 9 months preceding vaccine administration were retrospectively analysed to identify the burden of infections occurring before vaccination.

RESULTS

The serological assays were used for monitoring the antibody titres during the observational period. Vaccination significantly reduced the rate of infection and elicited a specific humoral response, which lasted during the whole observational period (9 months). A decay was observed in all considered subgroups. At 35 weeks, workers with no history of pre-vaccine infection showed a significantly lower anti-S titre (-2522 U/mL on average (-2589.7 to -2445.7)); younger workers showed significantly higher anti-S titres (140.2 U/mL on average (82.4 to 201.3)). Only seven immunocompromised workers did not show significant levels of anti-S antibodies; three of them, all females, showed a specific T-cell response.

CONCLUSIONS

Comparing the 9-month periods before and after the first vaccine dose, a significant reduction in infection rate was observed (1708 cases vs. 156). Pre-vaccine infection, especially if contracted during the first pandemic wave, greatly enhanced the response to vaccination, which was significantly affected also by age both in extent and duration (inversely related). A gender effect on the T-cell immune response was observed in a small group of workers who did not produce antibodies after vaccine administration.

Ex-vivo study about antimicrobial effectiveness of phytic acid against Enterococcus faecalis into root canals

BACKGROUND

Endodontic failure is due to the persistence of microorganisms, especially Enterococcus faecalis, which have become resistant to disinfection measures. Sodium hypochlorite has been traditionally used, whereas phytic acid, a natural irrigant, needs to be further investigated.

METHODS

This ex-vivo study compared the antibacterial effectiveness of 0.9% saline solution, 5% sodium hypochlorite and 5% phytic acid against Enterococcus faecalis ATCC 29212 into the apical root canal third of 96 single-rooted extracted teeth, after 1-minute push-and-pull irrigation - a basic irrigation technique. Survived microorganisms were evaluated both through a traditional colony-forming-unit count and introducing the viability PCR, which precisely detects only DNA from intact cells: dead and damaged cells were excluded thanks to a propidium monoazide dye.

RESULTS

The culture methods showed that 5% sodium hypochlorite (median: 0 CFU/mL) has a significant greater antibacterial effectiveness (P<0.001) compared both to 0.9% saline solution (median: 4.76 CFU/mL) and 5% phytic acid (median: 0.25 CFU/mL). However, 5% phytic acid proved to be significantly more effective (P<0.001) than 0.9% saline solution. The viability PCR did not reveal a significant difference between 5% sodium hypochlorite (median: 4.12×10⁴ survived bacteria) and 0.9% saline solution (median: 8.45×10⁴ survived bacteria). Five percent phytic acid (median: 0.83×10⁴ survived bacteria) was significantly more effective than both 0.9% saline solution (P<0.001) and 5% sodium hypochlorite (P<0.001).

CONCLUSIONS

The findings suggest that 5% phytic acid works against root canal bacteria even with a basic irrigation technique and viability PCR seems to lead to more reliable and sensitive data rather than the culture methods.

SARS-CoV-2 Breakthrough Infections: Incidence and Risk Factors in a Large European Multicentric Cohort of Health Workers

Background: The research aimed to investigate the incidence of SARS-CoV-2 breakthrough infections and their determinants in a large European cohort of more than 60,000 health workers. Methods: A multicentric retrospective cohort study, involving 12 European centers, was carried out within the ORCHESTRA project, collecting data up to 18 November 2021 on fully vaccinated health workers. The cumulative incidence of SARS-CoV-2 breakthrough infections was investigated with its association with occupational and social–demographic characteristics (age, sex, job title, previous SARS-CoV-2 infection, antibody titer levels, and time from the vaccination course completion). Results: Among 64,172 health workers from 12 European health centers, 797 breakthrough infections were observed (cumulative incidence of 1.2%). The primary analysis using individual data on 8 out of 12 centers showed that age and previous infection significantly modified breakthrough infection rates. In the meta-analysis of aggregated data from all centers, previous SARS-CoV-2 infection and the standardized antibody titer were inversely related to the risk of breakthrough infection (p = 0.008 and p = 0.007, respectively). Conclusion: The inverse correlation of antibody titer with the risk of breakthrough infection supports the evidence that vaccination plays a primary role in infection prevention, especially in health workers. Cellular immunity, previous clinical conditions, and vaccination timing should be further investigated.

Serosurvey in BNT162b2 vaccine-elicited neutralizing antibodies against authentic B.1, B.1.1.7, B.1.351, B.1.525 and P.1 SARS-CoV-2 variants

In this study, we show that BNT162b2 vaccine-elicited antibodies efficiently neutralize SARS-CoV-2 authentic viruses belonging to B.1, B.1.1.7, B.1.351, B.1.525 and P.1 lineages. Interestingly, the neutralization of B.1.1.7 and B.1.525 lineages was significantly higher, whereas the neutralization of B.1.351 and P.1 lineages was robust but significantly lower as compared to B.1 lineage. Following our findings, we consider that the BNT162b2 vaccine offers protection against the current prevailing variants of SARS-CoV-2.

Serological Response to SARS-CoV-2 in Health Care Workers Employed in a Large Tertiary Hospital in Lombardy, Northern Italy

BACKGROUND

COVID-19 pandemic is requesting unprecedented efforts by health-care workers (HCWs) in all countries, and especially in Italy during the first semester of 2020.

METHODS

This is a retrospective, observational study conducted at the Spedali Civili General Hospital, in Brescia, Northern Italy during the SARS CoV-2 pandemic in the first semester of 2020. Serum samples from HCWs were tested for SARS-CoV-2 spike protein-specific antibodies. An online survey was used to collect demographic, clinical, and epidemiological data.

RESULTS

Of the 1893 HCWs included, 433 (22.9%) were found seropositive for SARS-CoV-2 IgG. The cumulative prevalence of SARS-CoV-2 infection (antibodies production or past positive RT-PCR on nasal/throat swab) was 25.1% (475/1893). Fifty-six out of 433 (13%) seropositive participants declared to have been asymptomatic during the study period. The development of COVID-19 signs or symptoms is the main determinant of seropositivity (OR: 11.3, p < 0.0001) along with their duration and severity. 40/290 (14.5%) HCWs with documented positive RT-PCR during the study period did not show any detectable antibody response. IgG levels positively correlate with age, COVID-19-compatible signs and symptoms experienced and their duration.

CONCLUSIONS

In this study, carried out in one of the most affected areas in Europe, we demonstrate that most HCWs with COVID-19 related symptoms develop a spike protein-specific antibodies with potential neutralizing effect.

Poor predictive value of contemporary bleeding risk scores during long-term treatment of venous thromboembolism

Bleeding is a common and feared complication of oral anticoagulant therapy. Several prediction models have been recently developed, but there is a lack of evidence in patients with venous thromboembolism (VTE). The aim of this study was to validate currently available bleeding risk scores during long-term oral anticoagulation for VTE. We retrospectively included adult patients on vitamin K antagonists for VTE secondary prevention, followed by five Italian Anticoagulation Clinics (Cuneo, Livorno, Mantova, Napoli, Varese), between January 2010 and August 2012. All bleeding events were classified as major bleeding (MB) or clinically-relevant-non-major-bleeding (CRNMB). A total of 681 patients were included (median age 63 years; 52.0% female). During a mean follow-up of 8.82 (± 3.59) months, 50 bleeding events occurred (13 MB and 37 CRNMB), for an overall bleeding incidence of 9.99/100 patient-years. The rate of bleeding was higher in the first three months of treatment (15.86/100 patient-years) than afterwards (7.13/100 patient-years). The HAS-BLED showed the best predictive value for bleeding complications during the first three months of treatment (area under the curve [AUC] 0.68, 95% confidence interval [CI] 0.59–0.78), while only the ACCP score showed a modest predictive value after the initial three months (AUC 0.61, 95%CI 0.51–0.72). These two scores had also the highest sensitivity and the highest negative predictive value. None of the scores predicted MB better than chance. Currently available bleeding risk scores had only a modest predictive value for patients with VTE. Future studies should aim at the creation of a new prediction rule, in order to better define the risk of bleeding of VTE patients.

Rotary versus reciprocating shaping files in bacterial elimination from long oval canals

A comparison of the abilities of rotary versus reciprocating files to eliminate viable Enterococcus faecalis populations from the long oval root canals of extracted human teeth. Fifty teeth were contaminated and randomly distributed into two groups (n = 25 each): BT-RaCe group and WaveOne group. Two microbial samples were obtained from each tooth before (S1) and after (S2) instrumentation. The CFUs from the S1 and S2 measurements were calculated and compared between the groups. Both groups showed significantly fewer CFUs in the S2 samples (P < 0.001). In the S2 intragroup comparison, BT-RaCe resulted in significantly fewer CFUs than WaveOne (P = 0.010). In the direct comparison between the rotary multiple file shaping system and the reciprocating single-file system, the multiple file system was more efficient at reducing the microbiological load of viable E. faecalis from long oval root canals.

The relationship between ABO blood group and cardiovascular disease: results from the Cardiorisk program

BACKGROUND

The ABO blood group exerts a profound influence on hemostasis, and it has hence been associated with the development of thrombotic cardiovascular adverse events. In this study, we evaluated the relationship between the ABO blood group and the risk of cardiovascular disease assessed with the Cardiorisk score.

METHODS

All blood donors aged between 35 and 65 years were enrolled in the Cardiorisk program, which included the assessment of 8 variables (sex, age, total cholesterol, high-density lipoprotein (HDL) cholesterol, plasma glucose, arterial blood pressure, anti-hypertensive therapy and smoking) which were used to generate a score. Individuals with a resulting score ≥20, considered at high cardiovascular risk, underwent additional instrumental tests (chest X-ray, stress electrocardiogram and Doppler ultrasound of supra-aortic trunks) and were closely clinically monitored.

RESULTS

Between January 2005 and December 2015, 289 blood donors with Cardiorisk ≥20 were identified, 249 of whom were included in the study with at least 2 years of follow-up. Among these, 36 (14.5%) had instrumental abnormality tests and developed adverse cardiovascular events (10 acute coronary syndrome, 2 cerebral ischemia, 3 cardiac arrhythmia, 8 stenosis of supra-aortic trunks or iliac arteries) during a median follow-up of 5.3 years. In this group of 249 high risk individuals, a statistically significant association (P=0.02) was found between the non-O blood type and the risk of developing subclinical or clinical cardiovascular events (odds ratio, 3.3; 95% CI, 1.1-10.1; P=0.033).

CONCLUSIONS

The results of this study underline the both key role of ABO blood group for the risk of developing arterial thrombotic events and the need for including such unmodifiable variable on the scores assessing the thrombotic risk.

Prevalence of Chlamydia trachomatis and Neisseria gonorrhoeae infection in adolescents in Northern Italy: an observational school-based study

BACKGROUND

We carried out a study to evaluate the prevalence of Chlamydia trachomatis and Neisseria gonorrhoeae genital infections in school-based adolescents in Northern Italy.

METHODS

Systematic screening for C. trachomatis and N. gonorrhoeae genital infection was performed in 13th grade students in the province of Brescia, an industrialized area in Northern Italy. Student filled in a questionnaire on sexual behaviour and provided a urine sample for microbiological testing.

RESULTS

A total of 2,718 students (mean age: 18.4 years; 59.1% females) provided complete data (62.2% of those eligible). Overall 2,059 students (75.8%) were sexually active (i.e. had had at least one partner), and the mean age at sexual debut was 16.1 years (SD: 1.4). Only 27.5% of the sexually active students reported regular condom use during the previous 6 months, with higher frequency in males than in females (33.8% vs 24.2%). No case of N. gonorrhoeae infection was detected, while C. trachomatis was found in 36 adolescents, with a prevalence of 1.7% (95% CI: 1.2-2.4) among sexually active students, and no statistical difference between females and males (1.9 and 1.4%, respectively). Inconsistent condom use (odds ratio, OR = 5.5) and having had more than one sexual partner during the previous 6 months (OR = 6.8) were associated with an increased risk of Chlamydia infection at multivariate analysis.

CONCLUSION

The prevalence of C. trachomatis infection among sexually active adolescents in Northern Italy was low, despite a high proportion of students who engage in risky sexual behaviour. No cases of N. gonorrhoeae infection were identified.

Association between particulate air pollution and venous thromboembolism: A systematic literature review

Air pollution is a leading global problem for public health. A number of ambient pollutants have been involved, including carbon monoxide (CO), nitrogen dioxide (NO2), sulfur dioxide (SO2), ozone (O3) and particulate matter (PM). Although exposure to PM has been linked to a wide array of cardiovascular and respiratory disorders, its effect on venous thrombotic disorders is still uncertain. To elucidate this issue, we have performed a systematic review on the existing literature on the association between PM and venous thromboembolism (VTE), using MEDLINE, EMBASE and Cochrane electronic databases. Of the 158 reviewed studies, 11 of them (3 case-crossover studies, 2 time-series studies, 2 case-control studies, 2 prospective cohort studies, 2 retrospective studies) involving more than 500,000 events fulfilled the inclusion criteria and results are presented here. Because there was substantial heterogeneity in study design, duration of follow-up, statistical measure of effects, clinical outcomes and threshold, we refrained to perform a quantitative analysis of the available data and carried out only a systematic review. Overall, the literature data suggest a link between PM and VTE, but further trials on larger populations of patients with homogeneous study designs and outcomes are warranted.

Correlation between ABO Blood Group, and Conventional Hematological and Metabolic Parameters in Blood Donors

BACKGROUND

Although several studies have investigated and confirmed the existence of an association between ABO blood type and several human disorders, especially with cardiovascular disease, little is known on the physiological influence or association of ABO blood groups on basal levels of some conventional hematological and metabolic parameters.

STUDY DESIGN AND METHODS

A total number of 7,723 consecutive healthy blood donors underwent laboratory testing at the time of their first blood donation, which apart from ABO typing included assessment of alanine aminotransferase, aspartate aminotransferase, gamma-glutamyl transferase, total bilirubin, total cholesterol, high-density lipoprotein cholesterol (HDL-c), low-density lipoprotein cholesterol (LDL-c), triglycerides, creatinine, iron, ferritin, uric acid, glucose, hemoglobin, and platelet count.

RESULTS

The most relevant finding was the identification of significantly higher values of total cholesterol and HDL-c in subjects with blood group A compared with those with O blood type, with the highest levels being observed in A1 subtype.

CONCLUSIONS

The positive association between A blood type and plasma lipid levels supports its potential role in the pathogenesis of atherosclerosis and the clinical observations of increased vulnerability to cardiovascular disease of individuals with non-O blood groups.

Management of Bleeding Associated with New Oral Anticoagulants

In the last few years, a great improvement in the management of clinical thromboembolism has been made thanks to the availability of novel oral anticoagulants. These drugs, which act by directly inhibiting thrombin (dabigatran) or activated factor X (apixaban, rivaroxaban, and edoxaban), offer several practical advantages over the traditional vitamin K antagonists (VKA), such as a more predictable anticoagulant effect with no need for routine coagulation monitoring and a limited drug and food interaction. Several phase III clinical trials have now been completed, overall demonstrating that non-VKA oral antagonists (NOACs) are at least as efficacious and safe as VKA in the prevention and treatment of thromboembolism. Nevertheless, patients receiving NOACs represent a new challenge because no antidotes are currently available for these drugs. In this review, after a description of the main pharmacologic characteristics and the main results of the clinical trials of NOACs, we will focus on the management of bleeding associated with these anticoagulant agents. A treatment algorithm of NOACs-associated bleeding is finally provided, with the aim of helping physicians in their daily care activity.

ABO blood group and von Willebrand factor: biological implications

ABO blood group antigens are complex carbohydrate molecules expressed on the surface of red blood cells and a variety of human cells and tissues. It is well known that ABO blood type exerts a profound influence on hemostasis, being a major determinant of von Willebrand factor (VWF), and consequently factor VIII, plasma levels. In this review, we will focus on the molecular mechanisms underlying the interaction between ABO blood group and VWF in normal and pathological conditions.

Lymphatic endothelial cells derived from metastatic and non-metastatic lymph nodes of human colorectal cancer reveal phenotypic differences in culture

Colorectal cancer is one of the most frequent causes of death in Western countries. Most patients develop metastasis traveling through the lymphatic system, and regional lymph node metastasis is considered a marker for dissemination, increased stage, and worse prognosis. Despite rapid advances in tumor biology, the processes that underpin lymphatic invasion and lymph node metastasis remain poorly understood. The aim of this study was to establish an easy protocol for isolation of pure tumor lymphatic endothelial cells derived from lymph nodes to study differences compared with normal endothelial cells of uninvolved tissue from the same patients. Cells were isolated with very high purity via magnetic cell sorting and express the specific lymphatic markers Prox-1 and Lyve-1. They show differences in expression of adhesion molecules, chemokines, and growth factor secretion, and capability to form capillaries when seeded on basal membrane, thereby, revealing important differences between the two cell type. These cultures may provide a promising platform for the comparative analysis of both cell types at the molecular and biological level and to optimize treatment strategies.

Cancer-associated thrombosis: investigating the role of new oral anticoagulants

Venous thromboembolism (VTE) is a common complication of cancer and has a significant impact on morbidity and mortality in patients with malignancies. Low molecular weight heparins (LMWHs) currently represent the drug of choice for both initial and long-term treatment of cancer-associated thrombosis. In recent years, however, a new class of novel oral anticoagulants (NOACs) inhibiting directly thrombin or activated factor X have been proposed as an alternative therapeutic option on the basis the results of subgroup analyses of phase III randomized controlled trials, including few cases of patients with cancer. After analysis of the available literature data, we conclude that although potentially interesting, future research specifically conducted in cancer patients is needed to clarify the role of these newer anticoagulant agents in prevention and treatment of cancer-related VTE.

Evolutionary aspects of ABO blood group in humans

The antigens of the ABO blood group system (A, B and H determinants) are complex carbohydrate molecules expressed on red blood cells and on a variety of other cell lines and tissues. Growing evidence is accumulating that ABO antigens, beyond their key role in transfusion medicine, may interplay with the pathogenesis of many human disorders, including infectious, cardiovascular and neoplastic diseases. In this narrative review, after succinct description of the current knowledge on the association between ABO blood groups and the most severe diseases, we aim to elucidate the particularly intriguing issue of the possible role of ABO system in successful aging. In particular, focus will be placed on studies evaluating the ABO phenotype in centenarians, the best human model of longevity.

Effects on bleeding complications of pharmacogenetic testing for initial dosing of vitamin K antagonists: a systematic review and meta-analysis

BACKGROUND

Although warfarin and other vitamin K antagonists (VKAs) are the most widely used oral anticoagulants for the prevention and treatment of thromboembolic events, a number of factors hamper their manageability, the most important being the inter-individual variability of the therapeutic dose requirement. Following the discovery of the influence of CYP2C9 and VKORC1 polymorphisms on VKA dose requirements, there has been interest in genotype-guided VKA dosing in order to reduce the risk of over-anticoagulation at the time of therapy initiation and hence the risk of bleeding, particularly prominent during the early days of treatment. To assess the impact on clinical outcomes of pharmacogenetic testing for initial VKA dosing, we have performed a systematic review and meta-analysis of the literature.

METHODS

MEDLINE, EMBASE and Cochrane databases were searched up to March 2014. Only randomized controlled trials comparing genotype-guided vs. clinically-guided warfarin dosing were included.

RESULTS

Nine trials including 2812 patients met the inclusion criteria and were pooled for meta-analytical evaluation. Risk of bias, assessed according to the Cochrane methodology, showed a low risk for the majority of domains analyzed in the included trials. A statistically significant reduction in the risk ratio (RR) for developing major bleeding events was observed in the pharmacogenetic-guided group compared with the control group (RR = 0.47; 95% CI, 0.23-0.96; P = 0.040).

CONCLUSIONS

The results of this meta-analysis show that genotype-guided initial VKA dosing is able to reduce serious bleeding events by approximately 50% compared with clinically-guided dosing approaches.

Multidisciplinary approach to congenital Toxoplasma infection: an Italian nationwide survey

Italy provides a free voluntary serological screening for toxoplasmosis in pregnancy supported by public health system, as there is an estimated congenital toxoplasmosis rate of 1-2/10,000. The aim of this study was to make an inventory of diagnostic and therapeutic protocols in use in Italy in the absence of a national guideline. A semistructured questionnaire was distributed to AMCLI (Italian Association of Clinical Microbiologists) members who were asked to involve other specialists to fill in the form. Data from 26 centers show: a) a general use of the IgG avidity test to solve diagnosis in IgG/IgM positive, pregnant women; b) a widespread attitude to spyramicin antenatal treatment in suspected, unconfirmed maternal infection; c) avoidance of invasive antenatal diagnosis only in suspected early or late (>24 weeks), even confirmed, maternal infection d) fetal diagnosis performed by PCR assays on amniotic fluid; e) variability of both indications and dosage of pyrimethamine-sulfadiazine (P-S) as fetal treatment; f) use of comparative mother and newborn IgG/IgM Immuneblot in most centers; g) no diagnostic tests performed on placenta and cord blood; h) spyramicin is no longer used in congenital infections; i) no P-S-based treatment for children at high risk of congenital infection (late maternal infection) in the absence of diagnosis. As there is the opportunity to test pregnant women for Toxoplasma gondii infection in Italy free of charge, standardized diagnostic and therapeutic national guidelines would focus on a more uniform approach.

Hemostatic agents for bleeding: recombinant-activated factor VII and beyond

A rapid restoration of hemostasis should be regarded as a primary goal for management of critical bleeding, which often represents a life-threatening condition. Among the various therapeutic strategies available in this clinical setting, we aim to summarize in this narrative review the current status on the use of recombinant-activated factor VII and prothrombin complex concentrates. The safety and effectiveness of these hemostatic agents in reversal of the anticoagulant effects of vitamin K antagonists will be also explored. In addition, their role in the management of acute bleeding associated with the newer direct oral anticoagulants dabigatran, rivaroxaban, and apixaban will be analyzed in a dedicated section.

Molecular epidemiology of Clostridium difficile strains from nosocomial-acquired infections

The purpose of this study is to analyze isolates of Clostridium difficile from patients with nosocomial acquired infection in respect to their molecular type and antimicrobial susceptibility. Fifty-nine randomly selected clinical isolates were characterized. Molecular typing was performed by rep-PCR (DiversiLab). Isolates were tested by disk diffusion towards 11 different antibiotics. All isolates were susceptible to metronidazole and vancomycin. Fifty five (93 %) isolates were resistant to erythromycin and fifty six (95 %) exhibited resistance to both clindamycin and moxifloxacin. Twenty rep-PCR types were identified, but most clinical isolates formed four major rep-PCR clusters (A1 24/59, 40 %; A2 20/59, 33 %; A3 5/59, 8 %; A4 3/59, 5 %). These results show high genetic variability, which demonstrate clearly the complexity of the strains of C. difficile and also show an increasing rate of resistance to fluoroquinolones in our region emphasizing the importance of implementing surveillance programs in order to prevent further spread of resistance in C. difficile.

Nosocomial outbreak of the pandemic Influenza A (H1N1) 2009 in critical hematologic patients during seasonal influenza 2010-2011: detection of oseltamivir resistant variant viruses

Background

The pandemic influenza A (H1N1) 2009 (H1N1pdm09) virus infection caused illness and death among people worldwide, particularly in hematologic/oncologic patients because influenza infected individuals can shed virus for prolonged periods, thus increasing the chances for the development of drug-resistant strains such as oseltamivir-resistant (OST-r) variant.

Methods

The aim of our study was to retrospectively evaluate the clinical importance of OST-r variant in circulating strains of the pandemic H1N1pdm09 virus. By means of RT-PCR and Sanger sequencing we analysed the presence of OST-r variant in 76 H1N1pdm09 laboratory-confirmed cases, hospitalized at the hematologic/oncologic ward at Spedali Civili of Brescia –Italy.

Results

Out of 76 hospitalized hematologic/oncologic patients, 23 patients (30.2%) were infected by H1N1pdm09 virus. Further investigation revealed that 3 patients were positive for the OST-r variant carrying the H275Y mutation. All the 23 infected patients were immuno-compromised, and were under treatment or had been treated previously with oseltamivir. Three patients died (13%) after admission to intensive care unit and only one of them developed H275Y mutation.

Conclusions

Our retrospective observational study shows that pandemic influenza A (H1N1) 2009 virus can cause significant morbidity and even mortality in hematologic/oncologic patients and confirms the high rate of nosocomial transmission of pandemic H1N1pdm09 virus in these critical subjects. Indeed, the reduction in host defences in these hospitalized patients favoured the prolonged use of antiviral therapy and permitted the development of OST-r strain. Strategies as diagnostic vigilance, early isolation of patients and seasonal influenza A(H1N1) vaccination may prevent transmission of influenza in high risk individuals.

Treatment of hemophilia B: focus on recombinant factor IX

Hemophilia B is a recessive X-linked bleeding disorder characterized by deficiency of the coagulation factor IX (FIX). In hemophilia B patients the severity of the bleeding phenotype is related to the degree of the FIX defect. Hemophilia B treatment has improved greatly in the last 20 years with the introduction first of plasma-derived and then of recombinant FIX concentrates. Replacement therapy may be administered through on-demand or prophylaxis regimens, but the latter treatment modality has been shown to be superior in prevention of hemophilic arthropathy and in improvement of patients' quality of life. The purpose of this narrative review is to summarize the current knowledge on treatment strategies for hemophilia B, focusing on recombinant FIX products either clinically used or in development. There is only one rFIX product that is licensed to treat hemophilia B patients; from the analysis of the literature data presented in this review, the authors conclude that this rFIX product has demonstrated an excellent safety profile and excellent clinical efficacy for halting and preventing bleeds in hemophilia B patients. While prophylaxis has emerged as the best therapeutic strategy for such patients because of its ability to prevent hemophilic arthropathy and to improve patients' quality of life, the pharmacokinetically tailored dosing of rFIX is another key point when planning hemophilia B treatment, as it allows optimization of the factor concentrate usage. Further clinical studies are needed to better assess the safety and efficacy (ie, the incidence of adverse reactions and inhibitor development) of newer rFIX products.

Prevalence of multidrug-resistant Acinetobacter baumannii and Pseudomonas aeruginosa in an Italian hospital

The severity and extent of disease caused by multidrug-resistant organisms (MDROs) varies by the population(s) affected and the institution(s) at which these organisms are found; therefore, preventing and controlling MDROs are extremely important. A retrospective study of patients who were infected with Acinetobacter baumannii or Pseudomonas aeruginosa was performed at the Spedali Civili Hospital in Brescia, Italy, from 2007 to 2010. A total of 167 (0.52%) A. baumannii isolates and 2797 P. aeruginosa (8.7%) isolates were identified among 31,850 isolates. Amikacin and colistin were the most active agents against A. baumannii strains. Multidrug resistance (MDR) was observed in 57 isolates (54%). Most MDR isolates (42 out of 57, 73%) were resistant to four classes of antibiotics. P. aeruginosa was recovered more frequently from the respiratory tract, followed by the skin/soft tissue, urine and blood. Colistin, amikacin and piperacillin/tazobactam were active against 100%, 86% and 75% of P. aeruginosa isolates, respectively. A total of 20% (n=316) of P. aeruginosa isolates were MDR. In summary, A. baumannii was more rare than P. aeruginosa but was more commonly MDR. Epidemiological data will help to implement better infection control strategies, and developing a local antibiogram database will improve the knowledge of antimicrobial resistance patterns in our region.

von Willebrand factor and cancer: a renewed interest

Von Willebrand factor (VWF), the largest human plasma protein, is an adhesive multimeric glycoprotein that mediates platelet adhesion to both the subendothelial matrix and endothelial surfaces and acts as a carrier for coagulation factor VIII in the circulation. Besides its essential role in hemostasis, there is growing evidence from the literature that VWF has an additional antitumor effect, mainly by exerting negative modulation on angiogenesis and apoptosis. Current knowledge on the link between VWF and cancer is summarized in this review, based on an analysis of the most important experimental and clinical studies.

LRP1/CD91 is up-regulated in monocytes from patients with haemophilia A: a single-centre analysis

The low-density lipoprotein receptor-related protein 1 (LRP1) is an ubiquitously expressed endocytic receptor that, among its several functions, is involved in the catabolism of coagulation factor VIII (FVIII) and in the regulation of its plasma concentrations. Although LRP1/CD91 polymorphisms have been associated with increased FVIII levels and a consequent thrombotic risk, no data are available on LRP1/CD91 expression in patients with inherited FVIII deficiency. With the aim of elucidating this issue, 45 consecutive patients with haemophilia A (HA) (18 severe, 5 moderate and 22 mild HA) were enrolled in this cross-sectional, single-centre survey. The LRP1/CD91 mean fluorescence intensity (MFI) in monocytes from HA patients was significantly higher than that detected in 90 healthy blood donors (105 vs. 67, P < 0.001). This over-expression was independent of hepatitis C virus infection status and varied according to the severity of the haemophilia, being higher in patients with more severe FVIII deficiency. In conclusion, our study documents for the first time that LRP1/CD91 is over-expressed on monocytes from HA patients, with the intensity of expression varying according to the severity of the FVIII deficiency. Further studies are needed to assess the clinical implications of these findings.

Relationship between ABO blood group and hemorrhage: a systematic literature review and meta-analysis

Several studies have suggested that patients with non-O blood group have an increased risk of both venous and arterial thromboembolic events. On the contrary, the role of ABO blood group on the risk of bleeding complications remains unclear. Thus, we performed a meta-analysis of the literature with the aim of assessing this potential association. MEDLINE and Embase databases were searched from 1946 to March 2012. Studies comparing the prevalence of different ABO blood groups in bleeding patients as well as in controls without bleeding complications were potentially includible. Two reviewers independently selected studies and extracted study characteristics, quality, and outcomes. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated for each trial and pooled using a random-effects model. Twenty-two studies totalling 9,468 bleeding patients and more than 450,000 controls were included. The prevalence of O blood group was significantly higher in bleeding patients than in controls, with a resulting pooled OR of 1.33 (95% CI = 1.25 to 1.42; p < 0.001). The result of this meta-analysis of a very large sample of bleeding patients and controls suggests that O blood group is a potentially important genetic risk factor for bleeding. High-quality prospective studies are warranted to confirm these preliminary findings.

Bleeding complications in patients with hematologic malignancies

Abnormalities of hemostasis are frequently encountered in patients with hematologic malignancies leading to both hemorrhagic and thrombotic adverse events. The prompt recognition and management of such complications, which have a negative impact on the morbidity and mortality of these patients, represents a major challenge for hematologists. This review describes the most important changes of hemostasis associated with hemorrhage in hematologic malignancies with particular emphasis on their contributory etiologic factors, complex pathogenic mechanisms, clinical manifestations, and therapeutic strategies. In particular, platelet and acquired coagulation abnormalities, bleeding complications in acute leukemia, and hematopoietic stem cell transplantation are discussed.

Incidence and antibiotic susceptibility of Mycoplasma hominis and Ureaplasma urealyticum isolated in Brescia, Italy, over 7 years

The prevalence and antimicrobial susceptibility of Ureaplasma urealyticum and Mycoplasma hominis collected during 2004-2011 were determined. A total of 9956 individuals was analyzed. Identification was performed by use of the mycoplasma IST-2 kit. Antimicrobial susceptibility against doxycycline, josamycin, ofloxacin, erythromycin, tetracycline, ciprofloxacin, azithromycin, clarithromycin, and pristinamycin was also tested by use of this commercial kit. Our results show a prevalence of 1856 positive patients for genital mycoplasmas (18.6 %). Among positive cultures, 89 and 1.1 % of isolates were Ureaplasma urealyticum and Mycoplasma hominis, respectively. For 9.8 % of isolates both urogenital mycoplasmas were grown. Doxycycline was the most active tetracycline for mycoplasma infections, and this is still the drug of first choice. Among macrolides, josamycin and clarithromycin are the most active agents against ureaplasmas; josamycin is also active against mycoplasmas and is an alternative to tetracyclines and erythromycin for mixed infections, especially for pregnant women and neonates. Fluoroquinolones had low efficacy against urogenital mycoplasmas. For Ureaplasma urealyticum, cross-resistance was found between erythromycin and macrolides (except josamycin) (40-80 %) and between erythromycin and ciprofloxacin (79 %). Antibiotic resistance over the test period did not vary significantly. Because of geographical differences among antibiotic resistance, local in-vitro susceptibility testing is recommended to avoid failure of therapy.

Haemophilia B: current pharmacotherapy and future directions

INTRODUCTION

Hemophilia B is a rare hereditary hemorrhagic disorder characterized by deficiency of the clotting factor IX (FIX). Hemophilia B patients experience mild to severe bleeding complications according to the degree of FIX defect. Nowadays, the most challenging complication of individuals with hemophilia B is the development of alloantibodies, which render the standard replacement therapy with FIX concentrates ineffective, exposing them to a significantly increased morbidity and mortality.

AREAS COVERED

This review summarizes the most important events leading to the development of the current FIX products available for the treatment of hemophilia B patients. In addition, it focuses on the more recent advances in the production of new FIX molecules aimed at improving the clinical management of such patients.

EXPERT OPINION

Although the availability of plasma-derived FIX concentrates has greatly improved the clinical management of hemophilia B patients, the introduction of FIX products using recombinant DNA technology has represented the most significant therapeutic progress in hemophilia B therapy, ensuring an advanced level of safety. The development of rFIX products with extended half lives will further improve the therapeutic armamentarium for hemophilia B patients.