ß-Cyclodextrin-based supramolecular poly(N-isopropylacrylamide) hydrogels prepared by frontal polymerization.

Frontal polymerization (FP) was successfully applied to the synthesis of poly(N-isopropylacrylamide)-grafted-acryloyl-ß-cyclodextrin supramolecularly crosslinked hydrogels. It was established that acryloyl-ß-cyclodextrin (AßCD) allowed performing successful frontal polymerizations with N-isopropylacrylamide even in the absence of any covalent crosslinker, which is something generally required. It was found that the swelling properties of the resulting hydrogels can be tuned by varying the amount of AßCD. Namely, when little amounts of this non-covalent crosslinker were used, superabsorbent hydrogels were obtained. Hydrogels containing also a covalent crosslinker were also prepared for comparison. These latter exhibited swelling ratios that are much lower than the others.

Could past Chlamydial vascular infection promote the dissemination of Chlamydia pneumoniae to the brain?

Chlamydia pneumoniae, a pathogen responsible for respiratory tract infections, has been associated with atherosclerosis which, along with hypertension, hyperlipidemia, cardiovascular and/or cerebrovascular ischemia and stroke, is a risk factor for chronic neurological disorders. Several studies have demonstrated the ability of C. pneumoniae to disseminate from lungs to arteries through peripheral blood mononuclear cells. Once inside the vascular tissue, C. pneumoniae infection may disseminate via peripheral monocytes to the brain over the intact blood-brain barrier, and contribute to the development of chronic neurological disorders. The aim of our study was to evaluate whether past C. pneumoniae vascular infection may promote the dissemination of this microorganism to the brain, therefore we investigated the presence of C. pneumoniae in post-mortem brain tissue specimens of patients with past chlamydial vascular infection. Seventy six post-mortem brain tissue specimens from 19 patients with past chlamydial vascular infection were investigated for the presence of C. pneumoniae by immunohistochemistry, polymerase chain reaction, in situ polymerase chain reaction and in situ reverse transcription polymerase chain reaction. As control, 28 brain tissue specimens were taken from 7 age and sex matched subjects without chlamydial infection. C. pneumoniae was detected in 16 (84.2%) out of 19 patients with chlamydial vascular infection whereas it was not detected in control subjects (p= 0.0002). In conclusion, the main result of our study is the evidence that a chlamydial vascular infection can disseminate to the brain. It will be important for current and future researches to perform large-scale prospective studies on cardiovascular patients with chlamydial vascular infection in order to evaluate the long-term pathological alterations of the brain.

Purity and stability of online-prepared hemodiafiltration fluid after storage.

BACKGROUND/AIMS: Previous studies have suggested that online hemodiafiltration (OL-HDF) fluid can be used as dialysate for continuous renal replacement therapies, and thus HDF costs can be reduced. The aims of this study were to determine the purity of OL-HDF fluid and to verify the stability of the electrolyte composition and acid-base balance during its storage. METHODS: OL-HDF fluid was collected in 70 individual bags and stored for up to 7 days. The following tests were performed daily in 10 bags: natural visible precipitation (macrocrystallization), sample collection for chemical analysis and fluid culture, limulus amebocyte lysate endotoxin test, standard culture of NALGENE® filters after passing of the fluid, and molecular analysis of bacterial DNA. RESULTS: The values of pH and pCO(2) showed a significant change starting at 24 h (p < 0.001); after 72 h, their values were beyond the measurable range. Coefficient of variation for pCO(2) was as high as 25.7%. Electrolyte composition (Na(+), K(+), Cl(-), Ca(2+) and glucose) showed a statistically significant difference over time (p < 0.05); however, their coefficients of variation were low (1.7, 1.4, 0.6, 2.3 and 0.9%, respectively), which might not be considered clinically significant. Negative results were obtained at all points by fluid and filter cultures, endotoxin test and molecular analysis. No macrocrystallization was observed at any time point. CONCLUSIONS: We demonstrate the microbiological purity of OL-HDF fluid stored for up to 7 days. The electrolyte composition was stable, except for a relevant change in pCO(2) and consequently in pH (first noted at 24 h), emphasizing the need to reassess the acid-base balance in multilayer plastic bags in future studies.

Septic shock, pneumonia, and soft tissue infection due to Myroides odoratimimus: report of a case and review of Myroides infections.

The genus Myroides comprises aerobic, yellow-pigmented, non-motile, non-fermenting gram-negative rods formerly classified as Flavobacterium odoratum. Members of the genus are widely distributed in the environment, especially in water, and usually behave as low-grade opportunistic pathogens, having been found to cause urinary tract infection, endocarditis, ventriculitis, and cutaneous infections in severely immunocompromised patients. We report a case of soft tissue infection, septic shock, and pneumonia due to M. odoratimimus in an immunocompetent male. To our knowledge, this is the first description of life-threatening infection caused by this organism in an immunocompetent host. We have also reviewed the medical literature on the genus Myroides.

Medical device disinfection by dense carbon dioxide.

The employment of disinfection-sterilisation processes for the re-use of medical devices without negative effects such as the presence of toxic residues, material degradation or other modifications is an important consideration for reducing the costs of surgical and medical procedures. Ethylene oxide is the most commonly used low temperature sterilisation technique in healthcare facilities, but its associated toxicity has reduced interest in this technology for the reprocessing of medical equipment. The aim of this study was to examine the disinfection efficiency of a novel low temperature approach, based on dense carbon dioxide on artificially contaminated catheters. The results obtained demonstrated that this method provided a complete inactivation of all bacteria and yeast strains tested, and that no obvious modifications to the surfaces tested were observed with multiple treatments.

Chlamydia pneumoniae infection as a risk factor for accelerated atherosclerosis in hemodialysis patients.

Atherosclerotic cardiovascular disease is the main cause of morbidity and mortality for end-stage renal disease patients undergoing chronic haemodialysis (HD). Several studies in recent years have identified Chlamydia pneumoniae, a respiratory pathogen, as risk factor for cardiovascular diseases in the general population. The aim of our study is to evaluate chlamydial load, in peripheral blood mononuclear cells (PBMC) of HD patients. Furthermore, the correlation between DNA chlamydial load and markers of inflammation was also examined. PBMC specimens isolated from 49 HD patients and 46 blood donors were analyzed for the presence of C. pneumoniae DNA by real-time PCR and ompA nested touchdown PCR. In HD patients, plasma levels of several inflammatory markers were also determined. A significantly higher rate of C. pneumoniae DNA was found in HD patients (44.9 percent) than in blood donors (19.6 percent) (p=0.016); HD patients were also more likely to have a significantly high chlamydial load (p=0.0004). HD patients with atherosclerotic cardiovascular diseases have a significantly greater chlamydial load than HD patients without cardiovascular diseases (p= 0.006). A significantly higher value of C-reactive protein, IL-6 and advanced oxidative protein products was found in HD patients with a greater chlamydial load (p less than 0.05). Likewise, a significantly lower monocyte HLA-DR percentage (p=0.011) as well as a lower monocyte HLA-DR expression were found in such patients (p= 0.007). In conclusion, our results show that HD patients are at high risk of C. pneumoniae infection correlated with chronic inflammatory response which in turn can lead to accelerated atherosclerosis and other long-term clinical complications such as myocardial infarction and stroke.

[Methylobacterium radiotolerans bacteremia in hemodialysis patients]. / Batteriemie da methylobacterium radiotolerans in pazienti emodializzati.

Central venous catheters (CVCs) play an important role in replacement therapy for patients with acute and chronic renal failure. Secondary infections due to central venous access are responsible for 48-73% of bacteremia in hemodialysis patients and are an important cause of morbidity and increased health costs for these patients. Episodes of unexplained fever were noted in hemodialysis patients in our center starting in October 2006. An investigation for causative microorganisms was conducted from October 2006 to April 2007. Bacterial DNA was extracted and amplified using universal primers for bacterial 16S. Amplification by multiple PCR was performed on the samples and the subsequent sequencing led to the identification of the microorganism of interest as belonging to Methylobacterium radiotolerans. We report the largest cluster of dialysis catheter-related bloodstream infections caused by M. radiotolerans, and describe the difficulties in the prompt and correct identification of these bacteria. Thirty-seven patients had positive cultures for M. radiotolerans from blood (2.7%) or CVC (29.7%) or both (67.6%). After removal and replacement of CVCs and antibiotic therapy and the strict application of an infection management protocol, there were no more fever episodes or cultures positive for M. radiotolerans.

Clustering and risk factors of methicillin-resistant Staphylococcus aureus carriage in two Italian long-term care facilities.

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) is a well-recognized agent of health care-associated infections in long-term care facilities, but few data about the circulation of MRSA in this setting in Italy are available. The aim of the study is to determine the prevalence and risk factors for MRSA carriage in nursing home residents in Vicenza (northeastern Italy). PATIENTS AND METHODS: A point prevalence survey was conducted in two long-term care facilities (subdivided into 15 wards) from 12 June 2006 to 6 July 2006. Anterior nasal swabs were obtained from residents and laboratory screening for MRSA was performed; full antibiotic susceptibility was assessed in MRSA isolates. Macrorestriction analysis of chromosomal DNA was carried out by pulsed field gel electrophoresis (PFGE). For each subject, demographic data, length of stay, dependency, cognitive function, presence of medical devices, comorbidities, current and previous antibiotic treatment, previous hospital admission and presence of infection were assessed on the day of sample collection. Factors that were found to be significantly associated with MRSA carriage at univariate analysis were introduced into multilevel logistic regression models in order to estimate the odds ratios (OR) with 95% confidence intervals (CI) for the risk of MRSA colonization, taking into account the clustering of patients within wards. RESULTS: Nasal swabs were obtained in 551 subjects; overall 43 MRSA carriers were detected (7.8%; CI = 5.7-10.4%). The rate of nasal carriers was very similar in the two institutions, and varied from 0% (0/36) to 18% (7/39) between wards. Only two out of 15 wards were found to have no MRSA carriers; overall, three pairs of colonized roommates were detected. Upon multilevel logistic regression, the risk of MRSA carriage was increased in patients with cancer (OR = 6.4; CI = 2.5-16.4), in those that had undergone recent hospitalization (OR = 2.2; CI = 1.0-4.4), and it reached OR = 4.0 (CI = 1.7-9.9) in those with three or more antibiotic treatments in the previous year; about 10% of the variability in MRSA carriage could be attributed to differences between wards. Pulsed field gel electrophoresis analysis permitted the definition of six clusters; two of these comprised 78.6% of the studied isolates and were quite similar, with one being more strongly represented among subjects hospitalized in the previous 12 months. All of the MRSA strains were resistant to ciprofloxacine; nevertheless, the majority were susceptible to most other non-betalactam antibiotics. CONCLUSION: The study suggests that nursing homes are a significant reservoir for MRSA. Statistical and PFGE analyses indicate a scenario where MRSA seems to be endemic and individual risk factors, namely recent hospitalizations and repeated antibiotic treatments, play a major role in the selection of drug-resistant organisms. Infection control measures should be coordinated among different health care settings, and the appropriate use of antibiotics has emerged as an important issue for improving the quality of care.

Residual of bacterial DNA in hemodialyzers: the proof of subclinical infection sustaining chronic inflammation.

BACKGROUND AND PURPOSE: Inflammation and infection seem to be important causes of morbidity and mortality in Chronic Kidney Disease (CKD) patients. Subclinical infections have been proposed as an important cause of inflammatory syndrome but to date this hypothesis remains speculative. In this investigation, we developed a method for molecular detection of the presence of bacterial DNA in a population of chronic kidney disease patients in order to correlate molecular data with the degree and level of inflammation and to evaluate the usefulness of the method in the diagnosis of subclinical infection. DESIGN: The study was divided into two phases: the study of a population of 81 CKD patients for prevalence and level of inflammation and infection; and the molecular evaluation of a subgroup of 38 patients without evident clinical causes of inflammation for molecular evaluation of subclinical infection. RESULTS: Patients hemoculture negative turned out positive for the presence of bacterial DNA when molecular methods were used. We found a trend of correlation with the presence of bacterial DNA and the increase in hs-CRP, IL-6 and oxidative stress (AOPP) levels and a reduction in MFI DR+. Hemodialyzer membranes seem to have properties that are 'sticky' to bacteria/bacterial DNA and work as concentrators. Moreover our data suggest that DNA can traverse hemodialysis membranes. CONCLUSIONS: Molecular methods have turned out to be far more sensitive than standard methods in detecting subclinical infection. The presence of bacterial DNA seems to influence the variation of some parameters of inflammation and immunity. Apart from the limitations and pitfalls, a molecular method could be useful for the screening of subclinical infection and diagnosis of sepsis when the hemoculture is negative. The identification of the microorganism involved, however, must be done with species-specific primers. These results are preliminary and more investigations will have to be performed in order to confirm our results.

Inflammation and subclinical infection in chronic kidney disease: a molecular approach.

Inflammation and infection seem to be important causes of morbidity and mortality in chronic kidney disease (CKD) patients; subclinical infections have been proposed as an important cause of inflammatory syndrome, but to date this hypothesis remains speculative. We developed a method for the molecular detection of the presence of bacterial DNA in a population of CKD patients in order to correlate the molecular data with the degree and level of inflammation and to evaluate its usefulness in the diagnosis of subclinical infection. The study was divided into two phases: (1) a population of 81 CKD patients was screened for the prevalence and level of inflammation and the presence of possible infection, and (2) a subgroup of 38 patients, without evident clinical causes of inflammation, underwent complete molecular evaluation for subclinical infection using bacterial DNA primers for sequencing. Additionally, complete analysis was carried out in the blood and dialysate compartments of the hemodialyzers used. The general population showed a certain degree of subclinical inflammation and no difference was found between patients with and without evident causes of inflammation. Hemoculture-negative patients were positive for the presence of bacterial DNA when molecular methods were used. We found a correlation trend between the presence of bacterial DNA and the increase in hs-CRP, IL-6 and oxidative stress (advanced oxidation protein product) levels and a reduction in the mean fluorescence intensity for HLA-DR. Hemodialyzer membranes seem to have properties that stick to bacteria/bacterial DNA and work as concentrators. In fact, patients with negative bacterial DNA in the circulating blood displayed positivity in the blood compartment of the dialyzer. The dialysate was negative for bacterial DNA but the dialysate compartment of the hemodialyzers used was positive in a high percentage. Moreover our data suggest that bacterial DNA can traverse hemodialysis membranes. Molecular methods have been found to be far more sensitive than standard methods in detecting subclinical infection. The presence of bacterial DNA seems to influence the variation in some parameters of inflammation and immunity. Apart from the limitations and pitfalls, the molecular method could be useful to screen for subclinical infection and diagnose subclinical sepsis when the hemoculture is negative. However, the identification of the microorganism implicated must be done with species-specific primers.

Impact of liver steatosis on virological response in [corrected] Italian patients with chronic hepatitis C treated with peg-interferon alpha-2b plus ribavarin.

BACKGROUND: Whether liver steatosis affects sustained virological response in patients with chronic hepatitis C is still under discussion. AIM: To evaluate the impact of liver steatosis in patients treated (for chronic hepatitis C) with combination therapy. METHODS: We evaluated 97 (male/female 82/15, mean age 41.1 years) consecutive naive patients treated with pegylated interferon alpha-2b plus ribavirin. RESULTS: Prevalence and severity of liver steatosis were significantly associated with genotype 3a [grade 3-4 in 14 of 32 patients (44%) vs. 8 of 65 patients (12%) with other genotypes; P = 0.001], while steatosis grade 1 (<10% of hepatocytes affected) was more frequently associated with genotype 1a/1b [9/39 (23%) vs. 4/57 (7%); P = 0.02]. Overall, sustained virological response was 62.8%, and was statistically uninfluenced by the presence/absence of liver steatosis. On the contrary, the following variables were independently associated with sustained virological response at logistic regression analysis: genotype other than 1a/1b, positive association, (odds ratio 3.4, P < 0.04), and low-grade liver steatosis, negative association, (odds ratio 9.0, P = 0.009), whereas sustained virological response was unaffected by severe liver steatosis, which was mainly associated with genotypes 2 and 3 [steatosis grade 2, 18/29 (62%); grade 3, 10/12 (83%); grade 4, 7/10 (70%)]. CONCLUSIONS: Only low-grade liver steatosis negatively affects the outcome of combination therapy, with peginterferon alpha-2b plus ribavirin, while severe steatosis (which is virus-related in most cases) has no impact on virological response.

Chlamydia pneumoniae infection in HIV-positive patients: prevalence and relationship with lipid profile.

OBJECTIVES: The aims of this study were to evaluate the prevalence and impact of Chlamydia pneumoniae infection in HIV-positive patients and to establish the relationship between C. pneumoniae infection and lipid profile. METHODS: Detection of C. pneumoniae was by polymerase chain reaction (PCR) on Peripheral Blood Mononuclear Cells (PBMCs) collected from 97 HIV-positive patients. Samples were collected after overnight fast in EDTA-treated tubes. On the same day, patients were also tested for routine chemistry, HIV viral load, CD3, CD8 and CD4 cell counts and lipid profile [cholesterol, high-density lipoproteins (HDLs), low-density lipoproteins (LDLs) and triglycerides]. RESULTS: The overall prevalence of C. pneumoniae was 39%. The prevalence of C. pneumoniae was inversely related to the CD4 lymphocyte count (P=0.03). In the naive group, C. pneumoniae-positive patients had both significantly higher HIV load (71 021+/-15 327 vs. 14 753+/-14 924 HIV-1 RNA copies/mL; P=0.03) and lower CD4 cell count (348.0+/-165.4 vs. 541.7+/-294.8; P=0.04) than C. pneumoniae-negative patients. Moreover, treatment-naive patients with C. pneumoniae infection had significantly higher mean levels of cholesterol (185.3+/-56.2 vs. 124.8+/-45.9 mg/dL; P=0.01), triglycerides (117.2+/-74.7 vs. 68+/-27.6 mg/dL; P=0.04) and LDL (122.4+/-60.1 vs. 55.6+/-58 mg/dL; P=0.05) than C. pneumoniae-negative patients. CONCLUSIONS: These data indicate that, in HIV-positive subjects, C. pneumoniae infection is relatively frequent and is associated with both low CD4 cell count and high HIV load. Furthermore, C. pneumoniae appears to be associated with hyperlipidaemia and might therefore represent a further risk factor for cardiovascolar disease in HIV-positive patients.

Influence of Helicobacter pylori infection on severity of oesophagitis and response to therapy in the elderly.

BACKGROUND: The prevalence both of Helicobacter pylori infection and oesophagitis is higher in the elderly, than in adult and young populations. However the relationship between Helicobacter pylori infection and the clinical behaviour of oesophagitis has not yet been clarified. AIM: To evaluate the influence of Helicobacter pylori infection on the severity and clinical outcome after treatment of oesophagitis in elderly patients. METHODS: A total of 271 elderly patients (134 male, 137 female, mean age = 79.2 years, range 65-96) with grade 1 to 3 oesophagitis were studied. At baseline, the patients were divided into 3 groups according to Helicobacter pylori infection: Group 1 = 88 Helicobacter pylori-negative patients; Group 2 = 59 Helicobacter pylori-positive patients and Group 3 = 124 Helicobacter pylori-positive patients who underwent a one-week proton pump inhibitor-based triple therapy for the eradication of Helicobacter pylori infection. All patients were treated with proton pump inhibitors for two months; patients in Group 3 were also treated for one week with proton pump inhibitors plus two antibiotics. After two months, endoscopy and histology were repeated. RESULTS: At baseline, 32.5% of patients were Helicobacter pylori-negative and 67.5% were Helicobacter pylori-positive. No baseline differences in severity of oesophagitis were found between Helicobacter pylori negative and positive patients. After proton pump inhibitor therapy, the complete resolution of oesophagitis was observed in 80.7% of Group 1, 76.3% of Group 2 and 75.8% of Group 3 (p=ns). Dividing patients also according to the severity of oesophagitis, no difference in healing rates between the three Groups were observed. CONCLUSIONS: In this elderly population, Helicobacter pylori infection did not influence the severity of oesophagitis at baseline or the response to short-term treatment with proton pump inhibitors. Furthermore, Helicobacter pylori eradication therapy did not influence the healing rate of oesophagitis.

Epidemiological analysis of vancomycin-resistant enterococci in a large tertiary-care hospital in Northern Italy.

The epidemiology of vancomycin-resistant enterococci (VRE) was studied in a large tertiary-care hospital in northern Italy from February 1993 to December 1999. Sixteen cases of bacteraemic and 17 cases of nonbacteraemic active infections caused by VRE were recorded. Fifteen of the bacteraemic and four of the nonbacteraemic infections occurred in patients in the haematology department, while the remainder were registered in other departments of the same hospital. Active surveillance for the presence of VRE in stools led to identification of 51 noninfected carriers over the 1994-1999 period; of these, 32 were haematology patients and the remainder were patients admitted to other departments. All VRE isolates carried the vanA gene. Forty-one Enterococcus faecium isolates and eight Enterococcus faecalis isolates collected in the 1993-1996 period were typed by pulsed-field gel electrophoresis. Twenty-nine isolates of Enterococcus faecium shared either indistinguishable or strictly or possibly related patterns. Of these, 26 were isolated from patients in the haematology department. This is believed to be the first study on the epidemiology of VRE carried out in a large hospital in Italy over a period of several consecutive years. It reports an increase in VRE due to the epidemic spread of genetically related strains and sporadic infections or colonisation by unrelated VRE. It also documents the success of surveillance and of the measures adopted for preventing the spread of VRE in patients at risk.

Demonstration of Chlamydia pneumoniae in atherosclerotic arteries from various vascular regions.

Chlamydia pneumoniae (CP) has been reported to be a pathogenic agent in the mechanism leading to atherosclerosis. The majority of available data is focused mainly on coronary artery disease whereas the distribution of CP in different areas, associated with atherosclerotic disorders, has not been completely clarified. In this study we investigated the presence of CP in atheromasic plaques from five different vascular areas (basilary artery, coronary artery, thoracic aorta, abdominal aorta, renal arteries) using nested polymerase chain reaction (PCR) and immunohistochemical staining (IHC), in order to establish the putative association of CP with atherosclerotic disease. The same atheromasic plaques were also tested for the presence of Helicobacter pylori (HP) and cytomegalovirus (CMV), other putative agents of atherosclerosis, using a nested PCR technique. Our data indicate that the presence of CP can be demonstrated in 100% of patients tested, considering globally the five areas of analysis. On the other hand the presence of HP has been demonstrated in four out of 18 patients (22.2%), and CMV only in three out of 18 (16.6%). Our results strongly suggest an association between CP and atherosclerosis and highlight the need for the detection of CP in multiple vascular areas of the same patient.

Cure of Helicobacter pylori infection in elderly patients: comparison of low versus high doses of clarithromycin in combination with amoxicillin and pantoprazole.

BACKGROUND: Advancing age may influence clarithromycin's pharmacokinetics. No studies have yet compared the effects of different dosages of clarithromycin in combination with a proton pump inhibitor and amoxicillin in elderly patients. AIM: To compare the efficacy and tolerability of clarithromycin 250 mg vs. clarithromycin 500 mg twice daily (b.d.) in combination with pantoprazole and amoxicillin in elderly patients. METHODS: One hundred and fifty-four elderly patients with H. pylori-associated ulcer disease or chronic gastritis were consecutively randomized to receive pantoprazole 40 mg daily plus amoxicillin 1 g, and either clarithromycin 250 mg b.d. (PAC 250) or clarithromycin 500 mg b.d. (PAC 500). Two months after therapy, endoscopy and gastric biopsies were repeated. RESULTS: The cure rates of H. pylori infection in the PAC 250 and PAC 500 groups were, respectively, 83% and 79% (ITT analysis) and 94% and 88% (PP analysis) (P=N.S.). Significant decreases in chronic gastritis activity both in the body (P < 0.00001) and the antrum (P < 0.0001) of the stomach were found in H. pylori-cured patients, independently of clarithromycin dosage. Four patients in PAC 250 (5%) and seven in PAC 500 (9%) reported adverse events (P=N.S.). One patient in PAC 250 (25%) and three in PAC 500 (43%) discontinued the study because of these drug-related side-effects (P=N.S.). CONCLUSIONS: In elderly patients, 1-week triple therapy with a proton pump inhibitor, amoxicillin and clarithromycin is a highly effective and well tolerated anti-H. pylori treatment. With this combination, clarithromycin at the lower dose of 250 mg b.d. achieved excel- lent cure rates and minimized adverse events and costs.

Detection of Chlamydophila pneumoniae DNA in peripheral blood mononuclear cells of blood donors in the north-east of Italy.

Recent studies have implicated Chlamydia pneumoniae (now Chlamydophila pneumoniae) in the pathogenesis of atherosclerosis and demonstrated its presence within human peripheral blood mononuclear cells (PBMCs). In this study the presence of C. pneumoniae DNA was assessed, using nested PCR, in PBMCs from 169 active blood donors as a function of age, of specific antibodies and C-reactive protein. The results obtained demonstrated a high degree of global positivity (46.15%), which was higher in females (52%) than in males (43.7%). Seroepidemiological studies showed a high percentage of positivity both in subjects positive by PCR (65.91%) and negative by PCR (71.74%). The clinical implication of such finding are under study.

Noninvasive diagnosis of Helicobacter pylori infection in older subjects: comparison of the 13C-urea breath test with serology.

BACKGROUND: The potential influence of cognitive status, physical activities, comorbidity and cotreatments on the feasibility and diagnostic accuracy of two noninvasive diagnostic tests for Helicobacter pylori (Hp) infection, i.e., the 13C-urea breath test (13C-UBT) and serology (immunoglobulin G [IgG] anti-Hp antibodies), in older subjects is not known. METHOD: The study involved 100 consecutive symptomatic elderly subjects (mean age, 78.3 years; range, 65-96 years), who had undergone an upper gastrointestinal endoscopy. Patients were considered Hp positive if at least two of the three invasive methods, i.e. histology, culture, and/or the rapid urease test were positive for Hp infection. Patients were considered Hp negative if all three invasive methods were negative. The 13C-UBT was performed according to the European standard method and the assaying of IgG anti-Hp antibodies by enzyme-linked immunosorbent assay. Cognitive status and functional activities were determined by the Mini-Mental State Examination (MMSE), the activities of daily living (ADLs) and instrumental ADLs (IADLs). RESULTS: According to invasive methods, 49 patients were Hp positive and 47 were Hp negative (4 subjects were excluded from the study). Hp-positive patients demonstrated a significantly higher prevalence of peptic ulcers (p =.02) and activity of chronic gastritis (p<.0001) than Hp-negative subjects. The 13C-UBT demonstrated a sensitivity of 100%, a specificity of 95.7%, and a diagnostic accuracy of 97.9%. Serology had significantly lower sensitivity (74.4%), specificity (59%), and diagnostic accuracy (67%, p<.001) than the 13C-UBT. The feasibility and the diagnostic accuracy of the 13C-UBT were not altered by the cognitive status (MMSE) and functional activities (ADL, IADL) of the patients, their drug consumption, or the prevalence of concomitant diseases. CONCLUSIONS: In older subjects, the 13C-UBT had a significantly higher diagnostic accuracy than serology without influence of cognitive function, disability, comorbidity and cotreatments. This method may be considered an excellent, clinically useful, noninvasive test for the diagnosis of Hp infection in older subjects.