The metaproteome of the gut microbiota in pediatric patients affected by COVID-19

Introduction

The gut microbiota (GM) play a significant role in the infectivity and severity of COVID-19 infection. However, the available literature primarily focuses on adult patients and it is known that the microbiota undergoes changes throughout the lifespan, with significant alterations occurring during infancy and subsequently stabilizing during adulthood. Moreover, children have exhibited milder symptoms of COVID-19 disease, which has been associated with the abundance of certain protective bacteria. Here, we examine the metaproteome of pediatric patients to uncover the biological mechanisms that underlie this protective effect of the GM.

Methods

We performed nanoliquid chromatography coupled with tandem mass spectrometry on a high resolution analytical platform, resulting in label free quantification of bacterial protein groups (PGs), along with functional annotations via COG and KEGG databases by MetaLab-MAG. Additionally, taxonomic assignment was possible through the use of the lowest common ancestor algorithm provided by Unipept software.

Results

A COVID-19 GM functional dissimilarity respect to healthy subjects was identified by univariate analysis. The alteration in COVID-19 GM function is primarily based on bacterial pathways that predominantly involve metabolic processes, such as those related to tryptophan, butanoate, fatty acid, and bile acid biosynthesis, as well as antibiotic resistance and virulence.

Discussion

These findings highlight the mechanisms by which the pediatric GM could contribute to protection against the more severe manifestations of the disease in children. Uncovering these mechanisms can, therefore, have important implications in the discovery of novel adjuvant therapies for severe COVID-19.

C13 COMPARISON OF MINIMALLY INVASIVE VERSUS CONVENTIONAL THORACIC AORTIC OPERATIONS: EARLY AND MID–TERM RESULTS IN A SERIES OF 624 PATIENTS

Objective

Despite minimally invasive techniques have gained wider clinical application in cardiac surgery, current evidence on mini thoracic aortic surgery is still limited. The aim of this study was to compare early and mid–term outcomes of patients undergoing proximal thoracic aortic interventions through mini–sternotomy (MS) versus full sternotomy (FS).

Methods

Data from 624 consecutive patients undergoing proximal aortic operations through MS (n = 214, 34.3%) and FS (n = 410, 65.7%) at 2 aortic centers, were analysed. Patients with prior cardiac operations and active endocarditis, and those who underwent emergency operation and combined procedures were excluded. Treatment selection bias was addressed by the use of propensity score matching (MS vs FS). After matching, 2 well–balanced groups of 202 patients each were created. Surgical procedures involved aortic valve replacement/repair and ascending aorta replacement in 190 patients (47%), aortic root replacement in 110 patients (27.2%) and isolated ascending aorta replacement in 104 patients (25.7%).

Results

The median cardiopulmonary bypass and cross clamp times were 88 and 68 minutes, respectively, with no difference between groups. Overall 30–day mortality was 0.7%, being 1% (n = 2) in patients underwent MS and 0.5% (n = 1) in those underwent FS (p = 0.6). No difference was found in the rates of stroke (MS n = 5, 2.5%; FS n = 5, 2.5%), dialysis (MS n = 1, 0.5%; FS n = 4,2%), bleeding (MS n = 7, 3.5%; FS n = 7, 3.5%), and blood transfusions (MS n = 67, 33.3%; FS n = 57, 28.4%) (Table 1). Patients receiving MS were associated with a lower incidence of respiratory insufficiency compared with those receiving FS (0% vs. 2.5%, p = 0.03). The median intensive care unit length of stay was 24 and 25 hours in MS and FS group, respectively (p = 0.3), and in–hospital stay was 7 days both in MS and FS group (p = 0.9). Three–year survival rate was 96.6% in patients receiving MS and 95.7% in those receiving FS (p = 0.9).

Conclusions

Our findings showed that mini proximal aortic operations can be performed successfully without compromising the proven efficacy and safety of conventional access. In selected patients, MS was associated with very low mortality and morbidity rates. Additionally, MS demonstrated superior clinical outcomes as regards respiratory adverse events, when compared with FS.

New-Onset Anemia and Associated Risk of ESKD and Death in Non-Dialysis CKD Patients: A Multi-Cohort Observational Study

Background

Anemia is a common complication of chronic kidney disease (CKD), but its incidence in nephrology settings is poorly investigated. Similarly, the risks of adverse outcomes associated with new-onset anemia are not known.

Methods

We performed a pooled analysis of three observational cohort studies including 1031 non-anemic CKD patients with eGFR <60 mL/min/1.73 m² regularly followed in renal clinics. We estimated the incidence of mild anemia (hemoglobin 11–12 g/dL in women and 11–13 g/dL in men) and severe anemia (hemoglobin <11 g/dL or use of erythropoiesis-stimulating agents) during a 3-year follow-up period. Thereafter we estimated the risk of end-stage kidney disease (ESKD) and all-cause death associated with new-onset mild and severe anemia.

Results

The mean age was 63 ± 14 years, 60% were men and 20% had diabetes. The mean estimated glomerular filtration rate (eGFR) was 37 ± 13 mL/min/1.73 m² and the median proteinuria was 0.4 g/day [interquartile range (IQR) 0.1–1.1]. The incidence of mild and severe anemia was 13.7/100 patients-year and 6.2/100 patients-year, respectively. Basal predictors of either mild or severe anemia were diabetes, lower hemoglobin, higher serum phosphate, eGFR <30 mL/min/1.73 m² and proteinuria >0.50 g/day. Male sex, moderate CKD (eGFR 30–44 mL/min/1.73 m²) and moderate proteinuria (0.15–0.50 g/day) predicted only mild anemia. The incidence of anemia increased progressively with CKD stages (from 8.77 to 76.59/100 patients-year) and the proteinuria category (from 13.99 to 25.02/100 patients-year). During a median follow-up of 3.1 years, 232 patients reached ESKD and 135 died. Compared with non-anemic patients, mild anemia was associated with a higher adjusted risk of ESKD {hazard ratio [HR] 1.42 [95% confidence interval (CI) 1.02–1.98]} and all-cause death [HR 1.55 (95% CI 1.04–2.32)]. Severe anemia was associated with an even higher risk of ESKD [HR 1.73 (95% CI 1.20–2.51)] and death [HR 1.83 (95% CI 1.05–3.19)].

Conclusions

New-onset anemia is frequent, particularly in patients with more severe renal damage and in those with diabetes mellitus. The occurrence of anemia, even of a mild degree, is associated with mortality risk and faster progression towards ESKD.

Development and validation of the mental health professional culture inventory

AIMS

No instrument has been developed to explicitly assess the professional culture of mental health workers interacting with severely mentally ill people in publicly or privately run mental health care services. Because of theoretical and methodological concerns, we designed a self-administered questionnaire to assess the professional culture of mental health services workers. The study aims to validate this tool, named the Mental Health Professional Culture Inventory (MHPCI). The MHPCI adopts the notion of 'professional culture' as a hybrid construct between the individual and the organisational level that could be directly associated with the professional practices of mental health workers.

METHODS

The MHPCI takes into consideration a multidimensional definition of professional culture and a discrete number of psychometrically derived dimensions related to meaningful professional behaviour. The questionnaire was created and developed by a conjoint Italian-Canadian research team with the purpose of obtaining a fully cross-cultural questionnaire and was pretested in a pilot study. Subsequently, a validation survey was conducted in northern Italy and in Canada (Montreal area, Quebec). Data analysis was conducted in different steps designed to maximise the cross-cultural adaptation of the questionnaire through a recursive procedure consisting of performing a principal component analysis (PCA) on the Italian sample (N = 221) and then testing the resulting factorial model on the Canadian sample (N = 237). Reliability was also assessed with a test-retest design.

RESULTS

Four dimensions emerged in the PCA and were verified in the confirmatory factor analysis: family involvement, users' sexuality, therapeutic framework and management of aggression risk. All the scales displayed good internal consistency and reliability.

CONCLUSIONS

This study suggests the MHPCI could be a valid and reliable instrument to measure the professional behaviour of mental health services workers. The content of the four scales is consistent with the literature on psychosocial rehabilitation, suggesting that the instrument could be used to evaluate staff behaviour regarding four crucial dimensions of mental health care.

Complete excision with narrow margins provides equivalent local control to wider excision in breast conservation for invasive cancer

Background

Society of Surgical Oncology and American Society for Radiation Oncology guidelines define clear margins in breast-conserving therapy (BCT) as 'no ink on tumour', in contrast to the attainment of margins of at least 1 mm widely practised in the UK. The primary aim of this study was to explore clinical, surgical and tumour-related factors associated with local recurrence after BCT, with a secondary aim of assessing the impact of margin re-excision on the risk of local recurrence.

Methods

Patient demographics, surgical details, tumour characteristics and local recurrence were recorded for consecutive women with BCT undergoing surgery between January 1997 and January 2007. Margins were defined as clear (greater than 1 mm), close (less than 1 mm but no ink on tumour), reaches (ink on tumour) and clear after re-excision.

Results

A total of 1045 women of median age 54 (range 18-86) years were studied. Median follow-up was 89 (range 4-196) months. Local recurrence occurred in 52 patients (5·0 per cent). Ink on tumour was associated with local recurrence (hazard ratio (HR) 4·86, 95 per cent c.i. 1·49 to 15·79; P = 0·009). Risk of local recurrence was the same for close and clear margins (HR 1·03, 0·40 to 2·62; P = 0·954). In women with involved margins, re-excision was still associated with an increased local recurrence risk (HR 2·50, 1·32 to 4·72; P = 0·005). Oestrogen receptor negativity increased risk (HR 2·28, 1·28 to 4·06; P = 0·005).

Conclusion

Adequately excised margins, even when under 1 mm, provide equivalent outcomes to wider margins in BCT. Achieving complete excision at primary surgery achieves the lowest rates of local recurrence.

[Nephrological paradox]

Patients that are followed by nephrologists from the beginning of the illness, they show a deceleration in the progression of the Chronic Kidney Disease towards dialysis and a better quality of life (less osteodystrophy, anaemia and fluids overload, better pressure management). However, in 2013 it still exists a great lack of knowledge about the professional figure of nephrologist. Residents of Nephrological School of Catania decided to conduct a survey to evaluate common knowledge of renal diseases and their treatments. The survey was conducted in two cities of Sicily. The results show that people are generally uninformed and disoriented about renal illness and their risks.

Do patients with bipolar disorders receive evidence-based psychosocial interventions? a survey in Italy

Introduction

Research evidence on bipolar disorder supports the importance of patients’ active role to improve outcome and the efficacy of a number of psychosocial interventions. The lower cost and potential ease of dissemination of group psychoeducation suggest that this should be a first line approach, with more complex interventions, requiring highly specialized skills, reserved to selected patients. However, to what extent research models can be transferred to everyday practice remains to be seen.

Objectives

To explore the delivery of psychosocial interventions to bipolar disorders patients in routine mental health care.

Aims

To estimate the treated prevalence of bipolar disorders in Milan and to collect data about the variety of psychosocial interventions patients received by mental health services.

Methods

A survey of psychosocial interventions received by bipolar patients in three mental health services of Milan (catchment area 867,000 inhabitants) was conducted in 2009. Data from the Regional Mental Health Information System were retrieved to calculate the number of patients involved in psychosocial interventions and the kind of intervention provided.

Results

The treated prevalence rate was low, showing a probable treatment gap. Only 20% of 636 bipolar patients received at least one psychosocial intervention. The interventions provided were: family psychoeducation (3,8%), individual social skills training (11,5%), group social skills training (1,4%), and relatives group (3,0%).

Conclusions

Few bipolar patients receive psychosocial interventions in the MHS of Milan. Moreover, the interventions received were not specifically designed for bipolar disorder. Treatment gap could be reduced providing psychoeducation especially designed for bipolar patients.

Circulating E-selectin as a risk marker in patients with end-stage renal disease

BACKGROUND

E-selectin is a key adhesion molecule which plays a fundamental role in endothelial progenitor cell-dependent reparative mechanisms in experimental ischaemia and it serves to anchor leucocytes to the endothelium in inflammatory processes. Inflammation is one of the strongest risk factors for death and cardiovascular (CV) events in end-stage renal disease (ESRD).

OBJECTIVE

The objective of the current study was to evaluate whether E-selectin is a useful biomarker of clinical outcome in ESRD patients. We tested the prediction power of circulating E-selectin for mortality and CV events in a cohort of 265 ESRD patients.

RESULTS

During the follow-up, 59 patients died and 58 had CV events. All-cause mortality was inversely related to serum E-selectin, the risk of death being the lowest in patients in the third E-selectin tertile (HR: 1, reference group), intermediate in those in the second tertile (HR: 1.30) and the highest in patients in the first tertile (HR: 2.02, P = 0.01). Similarly, the risk of fatal and nonfatal CV events followed an inverse pattern being lowest in the third tertile (reference group) and highest in the first tertile (HR: 1.73, P = 0.03). The prediction power of E-selectin for death and CV events was confirmed in a Cox regression analysis where E-selectin emerged as an inverse predictor of these outcomes, particularly so in patients with severe inflammation.

CONCLUSIONS

These data are in keeping with the hypothesis that in systemic inflammation altered E-selectin shedding may play a role in arterial damage and implicates this adhesion molecule in atherosclerotic complications in a high-risk condition like ESRD.

Dialysis and kidney transplantation: similarities and differences in the psychological aspects of noncompliance

BACKGROUND

Dialysis and kidney transplantation represent two effective strategies in treating chronic uremia, albeit with different results. Our study compared the psychological aspects of two categories of patients: patients who faced kidney transplantation and have been on dialysis, and noncompliant patients treated with these therapies.

MATERIALS AND METHODS

On 170 patients (120 hemodialysis and 50 peritoneal dialysis) we used a personality analysis (MMPI2) and the COPE, which assessed the ability of patients to cope under certain conditions that can be perceived as stressful or, in any case, unusual. The screening succeeded in 11 cases among the first group and 9 in the second. Three of the 20 patients were considered to be partially noncompliant: 1 on peritoneal and the other 2 on hemodialysis. We also tested a control group of 300 people of different ages, sexes, social and cultural status, dates and kinds of transplantation (cadaveric or living donors). Of the 36 feedbacks received, only 30 were considered valuable.

RESULTS

The results of the research showed that patients with less than 2 years of dialysis treatment and patients with more than 2 years survival after transplantation time were inclined to deny their disease and the possible emotions about their clinical status, drawing an inadequate attention to the difficulties. This behavior was clearer among noncompliant patients. Family problems and couple malaise in everyday life can push more and more of these patients to be noncompliant with therapeutic prescriptions, as they do not feel adequate support. The result is an excessive foreboding, poor disposition, and nervousness.

CONCLUSIONS

Screening of patients' social and psychological status is useful as is psychological intervention for those who miss emotional support from the family. This psychological support is advisable for uremics who have to enter a waiting list and for those who are subject to postoperative treatment in order to promote compliant behavior.

Dielectric matrix and plasmon dispersion in strongly coupled electronic bilayer liquids

We develop a dielectric matrix and analyze plasmon dispersion in strongly coupled charged-particle bilayers in the T = 0 quantum domain. The formulation is based on the classical quasilocalized charge approximation (QLCA) and extends the QLCA formalism into the quantum domain. Its development, which parallels that of the two-dimensional companion paper [Phys. Rev. E 70, 026406 (2004)] by three of the authors, generalizes the single-layer scalar formalism therein to a bilayer matrix formalism. Using pair correlation function data generated from diffusion Monte Carlo simulations, we calculate the dispersion of the in-phase and out-of-phase plasmon modes over a wide range of high- r(s) values and layer separations. The out-of-phase spectrum exhibits an exchange-correlation induced long-wavelength energy gap in contrast to earlier predictions of acoustic dispersion softened by exchange and correlations. The energy gap is similar to what has been previously predicted for classical charged-particle bilayers and subsequently confirmed by recent molecular dynamics computer simulations.

[Non compliance predictive factors in renal transplantation]

Currently many authors report a kidney graft survival of 90-95% at one years post-transplantation. The patients' adherence to the immunosuppressive therapy is an important condition for maintaining graft functioning. A review of the medical literature shows that graft survival is significantly worse in non-compliance patients. As a matter of fact, 267 non compliance patients lost their graft of 7206 renal graft recipients. There are usually three different non-compliance profiles in transplantation : 1) 'Accidental non compliers' (47%) identifies those patients who sometimes forget to take the therapy. 2) 'Invulnerables' (28%) are those patients who believe that they do not need to take their immunosuppressive drugs regularly; 3) 'Decisive non compliers' (25%) are those patients who decide what therapy they should take. Many predictive factors have been associated with non compliance: 1) Demographic variables 2) Psychological variables 3) Psychiatric disorders 4) Poor social support 5) Pretransplantation compliance 6) Substance abuse We therefore think that it is particularly useful to identify non compliers before transplantation through psychological screening, in order to increase their compliance by supportive psychological assistance. Unfortunately, these patients tend to avoid specialists' intervention so it is very useful to provide the medical teams with the necessary training to cope with the psychological problems of their patients.

Fibrinogen, mortality and incident cardiovascular complications in end-stage renal failure

OBJECTIVE

Fibrinogen is an established predictor of cardiovascular events in the general population but the relationship between fibrinogen, mortality and incident cardiovascular complications has been very little investigated in patients with end-stage renal disease (ESRD).

DESIGN AND SUBJECTS

We investigated the relationship between fibrinogen and all cause mortality and cardiovascular outcomes in a prospective cohort study in 192 patients on chronic haemodialysis treatment (follow-up: 34 +/- 16 months).

RESULTS

Fibrinogen was significantly higher in patients who died during the follow-up than in those who survived. Similarly, fibrinogen was higher in patients who had fatal or nonfatal cardiovascular events than in event free patients. On multivariate Cox regression analysis fibrinogen was an independent predictor of survival [hazard ratio (1 g x L(-1) increase in plasma fibrinogen): 1.19, 95% confidence interval (CI): 1.05-1.35, P = 0.006] and a highly significant (P = 0.0008), independent predictor of fatal and nonfatal cardiovascular events [hazard ratio (1 g x L(-1) increase in plasma fibrinogen): 1.25, 95% CI: 1.10-1.43] in a model including traditional risk factors and serum C-reactive protein (CRP) and plasma homocysteine.

CONCLUSIONS

Fibrinogen is as an independent risk factor for overall and cardiovascular mortality in patients with ESRD. Intervention studies are required to see whether reducing plasma fibrinogen may help to curb the exceedingly high cardiovascular risk of the uremic population.

Fibrinogen, inflammation and concentric left ventricular hypertrophy in chronic renal failure

BACKGROUND

We investigated the relationship between fibrinogen and echocardiographic measurements of left ventricular (LV) geometry and LV function in a group of 192 patients with end stage renal disease (ESRD).

RESULTS

Patients in the third fibrinogen tertile had higher mean wall thickness (MWT), relative wall thickness (RWT) and left ventricular mass index (LVMI) and lower LV end diastolic diameter and LV ejection fraction than those in the other tertiles. On multivariate analysis fibrinogen resulted to be an independent correlate of MWT (P = 0.001) and RWT (P = 0.0001) and the first factor in rank explaining the variance in LV ejection fraction (P = 0.0001). Left ventricular concentric hypertrophy was more prevalent (P = 0.001) in patients in the third fibrinogen tertile (n = 35, 54%) than in those in the second (n = 24, 37%) and first (n = 13, 21%) tertiles. In a multiple logistic regression model patients in the third tertile of fibrinogen had a risk for left ventricular concentric hypertrophy that was 3.56 (95% CI: 1.56-8.14) fold higher than in those in the first tertile (P = 0.003).

CONCLUSIONS

Elevated fibrinogen is independently associated with LV concentric hypertrophy and systolic dysfunction in ESRD patients. These relationships may contribute to the negative prognostic impact of elevated fibrinogen levels in ESRD.

Excitonic condensation in a symmetric electron-hole bilayer

Using diffusion Monte Carlo simulations we have investigated the ground state of a symmetric electron-hole bilayer and determined its phase diagram at T = 0. We find clear evidence of an excitonic condensate, whose stability however is affected by an in-layer electronic correlation. This stabilizes the electron-hole plasma at large values of the density or interlayer distance, and the Wigner crystal at low density and large distance. We have also estimated pair correlation functions and low-order density matrices to give a microscopic characterization of correlations as well as to try and estimate the condensate fraction.

Circulating natriuretic peptide concentrations in patients with end-stage renal disease: role of brain natriuretic peptide as a biomarker for ventricular remodeling

OBJECTIVES

To determine levels of natriuretic peptides (NPs) in patients with end-stage renal disease (ESRD) and to examine the relationship of these cardiovascular peptides to left ventricular hypertrophy (LVH) and to cardiac mortality.

PATIENTS AND METHODS

One hundred twelve dialysis patients without clinical evidence of congestive heart failure underwent plasma measurement of NP concentrations and echocardiographic investigation for left ventricular mass index (LVMI).

RESULTS

Plasma atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) concentrations correlated positively with LVMI and inversely with left ventricular ejection fraction, whereas C-type NP and Dendroaspis NP levels did not correlate with LVMI. In dialysis patients with LVH (LVMI >125 g/m2), plasma ANP and BNP concentrations were increased compared with those in dialysis patients without LVH (both P<001). In a subset of 15 dialysis patients without LVH or other concomitant diseases, plasma BNP concentrations were not significantly increased compared with those in 35 controls (mean +/- SD, 20.1+/-13.4 vs 13.5+/-9.6 pg/mL; P=.06), demonstrating that the BNP concentration was not increased by renal dysfunction alone. Furthermore, the BNP level was significantly higher in the 16 patients who died from cardiovascular causes compared with survivors (mean +/- SD, 129+/-13 vs 57+/-7 pg/mL; P<.003) and was significantly associated with greater risk of cardiovascular death in Cox regression analysis (P<.001), as was the ANP level (P=.002).

CONCLUSIONS

Elevation of the plasma BNP concentration is more specifically related to LVH compared with the other NP levels in patients with ESRD independent of congestive heart failure. Thus, BNP serves as an important plasma biomarker for ventricular hypertrophy in dialysis patients with ESRD.

[Peripheral osteoma of the mandibular condyle. Two clinical cases]

Two cases of peripheral osteoma of the mandibular condyle are described. This lesions is uncommon. It is suggested that peripheral osteoma of the mandible may be traumatically induced and that muscle traction plays an important role in this lesion.

Smoking, blood pressure and serum albumin are major determinants of carotid atherosclerosis in dialysis patients. CREED Investigators. Cardiovascular Risk Extended Evaluation in Dialysis patients

AIM

To investigate the relationship between carotid atherosclerosis and some major cardiovascular risk factors in uremic patients on chronic dialysis.

METHODS

A cross-sectional study was carried out in 119 unselected dialysis patients (89 on hemodialysis and 30 on chronic ambulatory peritoneal dialysis, CAPD). Fasting blood sampling for serum lipids, albumin, hemoglobin, and echo-colour-Doppler evaluation of common carotid arteries were performed in all patients (during the non-dialysis day in hemodialysis patients). In hemodialysis patients BP was measured before and after dialysis; in CAPD patients home BP values were recorded during the month before the study day.

RESULTS

Ninety-five patients had at least one plaque and 57 had at least four plaques. Thirty-eight had mild and eleven severe carotid stenosis. In multiple regression models, the mean internal diameter of carotid arteries was explained (R=0.52, P=0.0001) by systolic pressure (r=0.39), serum cholesterol (r=-0.28), age (r=0.27) and smoking (r=0.24) while the degree of carotid stenosis was predicted (R=0.39, P=0.0001) by age (r=0.36) and smoking (r=0.25). The number of atherosclerotic plaques was explained (R=0.51, P=0.0001) by age (r=0.36), smoking (r=0.25) and pulse pressure (r=0.20), serum albumin just failing to reach statistical significance (P = 0.06). However, serum albumin was a significant and independent predictor of the number of atherosclerotic plaques (r=-0.26) in hemodialysis patients (n=89). Sex, diabetes, Kt/V, duration of dialysis treatment, hemoglobin, serum calcium and phosphate did not add any predictive power to the models.

CONCLUSIONS

In dialysis patients arterial pressure and smoking are associated with carotid atherosclerosis. Serum albumin appears to serve as an independent predictor of carotid atherosclerosis.

[Necrotizing sialometaplasia. Report of a case]

Necrotizing sialometaplasia is a benign lesion of the minor and major salivary glands. It occurs with a palatal swelling which rapidly becomes a deep ulcer. Histopathological aspects include ulceration of the surface epithelium, squamous metaplasia and acinar necrosis. In general no treatment is necessary and the lesion heals spontaneously in 4-10 weeks. This condition must be distinguished from more serious diseases such as squamous cell carcinoma and mucoepidermoid carcinoma.

Diagnosis of renovascular disease by extra- and intrarenal Doppler parameters

It is still a matter of debate as to which parameters should be used for noninvasive diagnosis of renovascular disease by renal Doppler sonography (RDS). The accuracy of RDS in the detection of renal artery stenosis (RAS) was tested in 95 consecutive, moderate to severe hypertensive patients (I-II World Health Organization [WHO] stages). Reno-aortic ratio (RAR) for peak systolic velocity (PSV) was also calculated to assist in the diagnosis of significant (>50%) RAS. Paired receiver-operating characteristic (ROC) analysis was plotted for evaluating the relationship between sensitivity and specificity for each parameter. In a subset of 57 kidneys, the influence of blood pressure and age on intraparenchymal parameters was evaluated. Measurements of maximal peak systolic velocity (PSV) at the site of stenosis, RAR for PSV, and minimum acceleration index in the main renal artery showed high accuracy (areas under the ROC curve 0.97, 0.88, and 0.80, respectively). Among intraparenchymal parameters, early systolic acceleration showed the best area under the ROC curve (0.90), but provided a low positive predictive value (29%) and was significantly influenced by blood pressure (multiple r=0.56; p=0.001). Pulsatility and resistive indices were found to be less powerful as absolute values, and both significantly influenced by blood pressure and age (multiple r=0.60 and 0.50; p=0.001, p=0.02, respectively). However, interindividual variance of intrarenal indices should be minimized by calculation of side difference, although this procedure would become misleading or impossible in patients with bilateral RAS or a single kidney, respectively. These results support the use of extraparenchymal parameters for noninvasive detection of RAS, and emphasize that intrarenal parameters cannot be considered as absolute values.

[The prevalence of serum anti-hepatitis C virus antibodies in hemodialyzed patients]

Hepatitis C virus (HCV) is responsible for a high percentage of cases of transfusional hepatitis and is often considered the etiological agent of numerous cases of non-A, non-B hepatitis in which parenteral transmission has not been documented. Patients undergoing hemodialysis are at risk for HCV infection. We used an immunoenzymatic method and confirmatory test (neutralization test) to determine serum anti-HCV antibody positivity in order to identify the factors associated with increased risk of HCV infection. We studied 63 hemodialyzed patients from eastern Sicily and compared the mean dialytic age and transfusion case history in positive and negative groups. 17.4 percent of the patients were anti-HCV positive. Mean dialytic age was significantly higher in the anti-HCV positive group. On the contrary no significant differences regarding transfusion case history or number of units of blood transfused were seen in the two groups. Our study confirms that hemodialyzed patients are at risk for HCV infection. This risk seems to increase with dialytic age. The lack of correlation between HCV and transfusion case history suggests that it may be a hospital-acquired infection.

[Evaluation of the risk of hepatitis delta virus (HDV) infection in a population of hemodialyzed patients: significance of the determination of anti-delta antibodies in the blood]

Hepatitis delta virus (HDV) is a defective virus which requires the helper function of hepatitis B virus (HBV) for replication. HDV infection occurs only during or after HDV infection. Viral infection spreads parenterally in both cases. However, it has been reported that the risk of HDV infection is limited to hemodialysed patients, unlike the risk of HBV infection. In order to verify these findings the Authors studied 108 patients undergoing periodical hemodialytic treatment in order to study the delta antibodies present in their blood. Sixty-one of these subjects had received previous blood transfusions, 15 were HBsAg positive and 7 positive for other serological markers of the hepatitis B virus. None of the subjects examined was positive for anti HDV. Our results agreed with the literature reporting an incidence of positive HDV serological markers limited to hemodialyzed patients. The Authors observed that the behaviour of the HDV serological markers can vary from patient to patient and that it is impossible to furnish diagnosis of HDV infection after HBV and HDV clearance. Since these factors can lead to underestimation of the real incidence of HDV infection in hemodialyzed patients, the Authors underline the need to perform long term epidemiological studies and to investigate all the HDV serological markers.