Novel data from Italian Vermamoeba vermiformis isolates from multiple sources add to genetic diversity within the genus.

Vermamoeba vermiformis represents one of the most common free-living amoebae identified in worldwide environmental surveys. We analyzed 56 water samples with varying characteristics, including temperature and the particular settings in which humans may be exposed to water, plus one corneal scraping from a keratitis patient, with the following aims: (i) to investigate the presence of V. vermiformis; (ii) to identify the isolate subtypes; (iii) to place the Italian isolates in the broader picture of the genetic diversity within V. vermiformis. Twenty-two isolates were identified upon culturing and sequencing of > 600 bp in the 18S ribosomal RNA (rRNA) gene sequence, bringing to 27 the number of sequences recovered from Italian sources. By adding deposited sequences, we assembled a dataset of 74 isolates. Three of our isolates were characterized by allelic code 7-5-1-1, never reported before, and two showed 100% identity with an uncultured eukaryote and carried the 719T>C variant. We show that the variable segments E5, E3, F, and G convey most of the information on diversity, enabling the clustering of the isolates in a replicable fashion. The presence of different strains in natural thermal waters and in distribution systems indicated heterogeneity of the amoebic populations. Also, ours and the only other sequence from human infection were mapped in different clades. Overall, we enlarged the repertoire of single nucleotide and indel variants and the list of allelic codes, proceeding one step further in the description of the diversity within the genus.

Blastocystis in Côte d'Ivoire: molecular identification and epidemiological data.

Blastocystis is an enteric protozoan infecting humans and animals in both developed and developing countries at all latitudes. Despite this, data on Blastocystis infection are not available for several geographical areas, including many African countries. In this study, a survey was conducted on Blastocystis among humans and domestic animals in rural and urban localities in Côte d'Ivoire, in order to investigate the prevalence, the subtype distribution, and the zoonotic potential in association with sociodemographic factors, seasonality, symptoms, and co-infections. A total of 110 fecal samples were collected from patients living in four localities. Molecular and phylogenetic analyses were conducted for Blastocystis detection and subtyping. Positive samples from symptomatic patients were tested by Luminex xTAG® Gastrointestinal Pathogen Panel (GPP) to evidence the presence of other common intestinal pathogens. Overall, a prevalence of 58.2% was observed in humans and subtypes ST1(50.0%), ST2 (22.0%) and ST3 (28.1%) were identified. The prevalence values varied significantly among the sites but not in relation to the subtype. The seasonal rains significantly increase the infection rate in all localities. No significant differences in the ST distribution between asymptomatic and symptomatic subjects were observed. As regard the zoonotic transmission, an additional sampling was conducted in another village where fecal samples were simultaneously collected from humans and animals. Blastocystis STs 1-3 and ST7 were identified in eight humans and four chickens, respectively. This study provides the first exhaustive data on the prevalence and molecular epidemiology of Blastocystis in Côte d'Ivoire.

Identification and phylogenetic position of Naegleria spp. from geothermal springs in Italy.

Naegleria spp. are free-living amoebae belonging to the family Vahlkampfiidae, in the class Heterolobosea. Among the recognized species, Naegleria fowleri causes primary amoebic meningoencephalitis (PAM), while two other species, Naegleria australiensis and Naegleria italica, have been reported as pathogenic in experimental animals. Due to the thermotolerance properties of some species, geothermal water sources including hot springs represent suitable habitats for their proliferation. The main aim of this study was a year-round sampling in two geothermal springs in Central Italy, to investigate the presence of Naegleria spp. using PCR/DNA sequencing based methods. The affinities between the sequences generated here and others reported in the literature were explored by using POY, which implements the concept of dynamic homology. Naegleria australiensis, Naegleria italica, and Naegleria lovaniensis, plus an unassigned Naegleria spp. were detected. Indels in the rDNA ITS1 and ITS2 turned out to be critical to distinguish the three species and confirmed their phylogenetic relationships. This is the first molecular report on the Naegleria spp. occurrence in geothermal waters in Central Italy, coupled with a fine genetic characterization.

Social determinants associated with Giardia duodenalis infection in southern Côte d'Ivoire.

The purpose of this investigation was to analyze the association between different social determinants of health at the local scale and Giardia duodenalis infection in diverse settlements in southern Côte d'Ivoire. Stool samples from 306 individuals aged 1-16 years were collected from six rural villages and a small town. Five variables were categorized to classify the increasing risk levels of acquiring intestinal parasites. Giardia prevalences (%) and odds ratios (ORs) were evaluated. Correlation and regression analyses were conducted to determine the correlation coefficients and to propose predictive models based on social determinants to forecast the risk of giardiasis. The overall observed prevalence of Giardia was 21.6 %. When the analysis was conducted at the local level, the percentage of infected people varied from a minimum of 12.7 up to 36.4 %. A significant association (p < 0.001) was found between the selected social determinants and G. duodenalis prevalence in the different localities. Correlation and regression analyses allowed us to describe two predictive models to estimate the OR of Giardia transmission. This study helps to clarify the possible impact of different social determinants of health on the risk of giardiasis at the local scale. Both predictive models could be suitable in order to assess the likelihood of the transmission of intestinal parasitic infection in developing countries.

Clinical efficacy of bronchodilators in equine asthma: Looking for minimal important difference.

BACKGROUND: Airway obstruction is the main trait of severe equine asthma that affects respiratory function and elicits detrimental effects on clinical presentation. Only few and underpowered clinical studies have investigated the impact of improvement in lung function induced by bronchodilators on the clinical signs of asthma-affected horses. OBJECTIVES: To identify the minimal important difference (MID) in lung function elicited by bronchodilator leading to a meaningful improvement in clinical signs. STUDY DESIGN: Pairwise meta-analysis and meta-regression analysis. METHODS: Literature searches were performed for studies that investigated the effect of bronchodilator therapy on lung function and clinical condition of asthmatic horses. The relationship between the change in lung function variables and clinical score was analysed via random-effect meta-regression. One-point change of the Improved clinically Detectable Equine Asthma Scoring System (IDEASS) score was used to identify the MID. RESULTS: A significant (P<0.05) relationship was found between the changes in IDEASS score and maximum change in transpulmonary pressure (ΔPplmax ) or pulmonary resistance (RL ). Since only the model resulting for RL passed through the origin (Y-intercept when X = 0: -0.31, 95% CI -0.75 to 0.14), this variable was used to identify the MID correlated with a meaningful improvement in clinical signs. The resulting MID value was a change in RL of 0.63 cm H2 O/L/s (95% CI 0.33-0.94), representing the slope of meta-regression model (high quality of evidence). MAIN LIMITATIONS: No long-term studies investigated the effect of bronchodilator agents on both lung function and clinical signs in asthmatic horses. CONCLUSIONS: In conclusion, bronchodilator pharmacotherapy in equine asthma elicits clinically meaningful effect when RL increases ≥1 cm H2 O/L/s, a value indicating the MID. Assessing the MID based on change in RL may improve the quality of evidence and the scientific impact of future clinical trials as it extends beyond the simple, and limiting, evaluation of statistical significance.

Acanthamoeba T4 and T15 genotypes associated with keratitis infections in Italy.

Thus far there is little data available concerning Acanthamoeba associated amoebic keratitis (AK) from Italy. In order to understand the incidence of Acanthamoeba in patients with ocular infections and to characterize the isolates at the molecular level, ocular specimens and contact lenses or lens case solutions from 140 patients were analysed by culture and by an 18S rRNA (Rns) gene-based PCR method. Nineteen (13.6%) patients showed Acanthamoeba culture positive samples. Eleven out of the 14 genetically characterized isolates were assigned to the T4 genotype. Three isolates, two of them from patients with keratitis responding to specific anti-Acanthamoeba therapy, were identified as belonging to the T15 genotype. This finding represents the first association between the T15 genotype and human amoebic keratitis. PCR amplification of the 18S ribosomal DNA proved to be a sensitive method, potentially able to detect Acanthamoeba without the need of long culture incubation, and thus considerably useful for clinical applications.

Pharmacological treatments in asthma-affected horses: A pair-wise and network meta-analysis.

BACKGROUND: Equine asthma is a disease characterised by reversible airflow obstruction, bronchial hyper-responsiveness and airway inflammation following exposure of susceptible horses to specific airborne agents. Although clinical remission can be achieved in a low-airborne dust environment, repeated exacerbations may lead to irreversible airway remodelling. The available data on the pharmacotherapy of equine asthma result from several small studies, and no head-to-head clinical trials have been conducted among the available medications. OBJECTIVES: To assess the impact of the pharmacological interventions in equine asthma and compare the effect of different classes of drugs on lung function. STUDY DESIGN: Pair-wise and network meta-analysis. METHODS: Literature searches for clinical trials on the pharmacotherapy of equine asthma were performed. The risk of publication bias was assessed by funnel plots and Egger's test. Changes in maximum transpulmonary or pleural pressure, pulmonary resistance and dynamic lung compliance vs. control were analysed via random-effects models and Bayesian networks. RESULTS: The results obtained from 319 equine asthma-affected horses were extracted from 32 studies. Bronchodilators, corticosteroids and chromones improved maximum transpulmonary or pleural pressure (range: -8.0 to -21.4 cmH2 O; P<0.001). Bronchodilators, corticosteroids and furosemide reduced pulmonary resistance (range: -1.2 to -1.9 cmH2 O/L/s; P<0.001), and weakly increased dynamic lung compliance. Inhaled ß2 -adrenoreceptor (ß2 -AR) agonists and inhaled corticosteroids had the highest probability of being the best therapies. Long-term treatments were more effective than short-term treatments. MAIN LIMITATIONS: Weak publication bias was detected. CONCLUSIONS: This study demonstrates that long-term treatments with inhaled corticosteroids and long-acting ß2 -AR agonists may represent the first choice for treating equine asthma. Further high quality clinical trials are needed to clarify whether inhaled bronchodilators should be preferred to inhaled corticosteroids or vice versa, and to investigate the potential superiority of combination therapy in equine asthma.

Prevalence and genotyping of human isolates of Giardia duodenalis from Albania.

Microscopical and PCR-based techniques were performed in order to investigate the prevalence of infection and the genotypes of Giardia duodenalis from 125 stool samples collected from children living in the urban and the rural areas of Tirana (Albania) and hospitalized with acute gastroenteritis. 7 out of 125 samples resulted positive for Giardia at the microscopic examination (5.6%). In 50 selected samples including the 7 samples positive for Giardia by microscopy, 3 and 15 additional positive samples were detected by immunofluorescence and PCR, respectively. Seasonality appeared as an important parameter to be evaluated in order to better understand the prevalence of infection. Sequence analysis revealed both human Assemblage A and B. This result represents the first data on G. duodenalis genotypes in Albania.

Helicobacter pylori-related disease: guidelines for testing and treatment.

OBJECTIVE: To develop practical guidelines for the treatment of patients with suspected and documented Helicobacter pylori-related gastroduodenal diseases. METHODS: A panel of physicians with expertise in H. pylori reviewed, critically appraised, and synthesized the literature on assigned topics and presented their overviews to the panel. Consensus was obtained in controversial areas through discussion. RESULTS AND CONCLUSIONS: The panel recommended testing for H. pylori in patients with active ulcers, a history of ulcers, or gastric mucosa-associated lymphoid tissue lymphomas. Young, otherwise healthy patients with ulcerlike dyspepsia and those with a family history or fear of gastric cancer may also undergo H pylori testing. Non-endoscopic methods are preferred for H. pylori diagnosis. Dual medication regimens should not be used for therapy; twice-daily triple therapy with a proton pump inhibitor or ranitidine bismuth citrate, clarithromycin, and amoxicillin for 10 to 14 days is an appropriate therapy. Posttreatment assessment of H. pylori status using urea breath testing should be considered in patients with a documented history of ulcer disease or with persistent symptoms.

Transmission and epidemiology of Helicobacter pylori.

Helicobacter pylori is one of the most common bacterial infections worldwide. However, the majority of those infected do not develop clinical manifestations of disease. This review discusses the epidemiology of the organism in terms of incidence and prevalence, the presumed means of transmission from person to person, and how typing of the organism has helped the epidemiologist. The epidemiology of disorders that are associated with H. pylori is also discussed.

Use of esmolol to control autonomic instability of tetanus.

Tetanus is often accompained by autonomic instability, rendering hemodynamic management difficult. Death is frequently secondary to an inability to control this instability. A variety of modalities have been used to stabilize the cardiovascular system, but all are not ideal. Esmolol offers theoretical advantages over other modalities. We report a case of severe tetanus in which a continuous infusion of esmolol was effective in controlling the autonomic instability.

Factors affecting solubility and penetration of clarithromycin through gastric mucus.

BACKGROUND: Factors influencing the pharmacokinetics of clarithromycin in gastric mucus are poorly defined. AIM: To determine: (i) whether the clinical formulation of clarithromycin (Biaxin granules and powdered Biaxin tablets) affects the water solvency of the antibiotic or changes the barrier properties of pig gastric mucus (PGM), thereby influencing the penetration of clarithromycin through the gastric mucus layer; and (ii) whether topically active anti-ulcer agents affect clarithromycin penetration through gastric mucus. METHODS: Solubility of clarithromycin in aqueous solution was studied at pH 7. PGM viscosities were determined using a falling ball microviscometer. Permeability of clarithromycin through PGM with and without added anti-ulcer drugs at pH 7 was monitored using a microfiltration device and an agar diffusion bioassay. RESULTS: Clarithromycin showed the poorest solubility at pH 7, whereas both Biaxin formulations demonstrated identical solubility of their antibiotic ingredient. Clarithromycin and both Biaxin formulations markedly increased mucin viscosity over the pH range 2-7. PGM markedly retarded the penetration of clarithromycin: unformulated clarithromycin and Biaxin tablets penetrated more rapidly through mucus than Biaxin granules. Pre-treatment of PGM with aluminium-magnesium-containing antacids (Riopan and Talcid preparations) decreased the rate of clarithromycin penetration, whereas Carafate and Peptobismol had no significant effect on mucus penetration of clarithromycin. CONCLUSIONS: The availability of clarithromycin in gastric mucus is significantly influenced by its clinical formulation, which affects its solubility as well as the viscous properties of mucus. Pulverized Biaxin tablets provide better local distribution of clarithromycin in mucus than Biaxin granules. Pre-treatment of mucus with anti-ulcer medications does not increase the penetration of clarithromycin through mucus.

Efficacy of a 1-week regimen of ranitidine bismuth citrate in combination with metronidazole and clarithromycin for Helicobacter pylori eradication.

BACKGROUND: In order to improve the efficacy and simplicity of the FDA-approved regimen of ranitidine bismuth citrate (RBC) and clarithromycin dual therapy, we added an inexpensive antibiotic (metronidazole), changed the dosage scheme to twice daily dosing, and decreased the duration of therapy to 1 week. METHODS: This was an open label study in which subjects with previously untreated Helicobacter pylori infection documented by serology or endoscopy and confirmed by the 13C-urea breath test received a 1-week course of RBC 400 mg b.d., metronidazole 500 mg b.d. and clarithromycin 500 mg b.d. A repeat breath test was performed 4-6 weeks after completing therapy. RESULTS: Forty-seven out of 50 subjects completed the protocol. Intention-to-treat and per protocol cure rates were 86% and 91%, respectively. The regimen was well tolerated. Study drugs were stopped in two patients due to side-effects. The most common side-effect was self-limited diarrhoea. CONCLUSION: Twice daily RBC-based triple therapy with metronidazole and clarithromycin for 1 week is well tolerated and effective in eradicating H. pylori infection.

Interaction of an aluminum-magnesium containing antacid and gastric mucus: possible contribution to the cytoprotective function of antacids.

BACKGROUND: Antacids are generally thought to protect the gastric mucosa from damage primarily by their ability to neutralize hydrochloric acid, but recently other mechanisms of antacid cytoprotection have been suggested. The aim of our study was to determine if the antacid hydrotalcit (Mg6Al2(OH)16CO3 x 4H2O) and its clinical formulations Talcid (suspension and tablet) can influence the acid barrier properties of pig gastric mucus (PGM). METHODS: Viscosities, flow patterns of injected HCl, and permeability to HCl were assayed in solutions of PGM with and without added antacid. RESULTS: Talcid-suspension markedly increased mucin viscosity between pH 2 and 7. In contrast, powdered Talcid-tablet and hydrotalcit noticeably reduced mucin viscosity at pH 5 and below. HCl barely diffused through PGM-Talcid-suspension, whereas the acid was able to quickly penetrate a PGM-Talcid-tablet powder or PGM-hydrotalcit mixture. When injected into a mixture of PGM-Talcid-suspension, HCl travelled in a single distinct channel whereas in both PGM-Talcid-tablet powder or PGM-hydrotalcit mixtures, the acid mixed irregularly throughout. Experiments with antacids alone revealed that Talcid-suspension, but not Talcid-tablet nor hydrotalcit, had barrier properties similar to PGM. CONCLUSION: Talcid-suspension has viscoelastic features similar to gastric mucin and may afford mucosal protection by its ability to maintain or mimic the barrier properties of gastric mucus gel. In contrast, powdered Talcid-tablets and hydrotalcit reduce the barrier function of gastric mucus.

A multicentre evaluation of the laser assisted ratio analyser (LARA): a novel device for measurement of 13CO2 in the 13C-urea breath test for the detection of Helicobacter pylori infection.

BACKGROUND: The laser assisted ratio analyser (LARA) was developed as a novel device to measure 13CO2 in the urea breath test for the detection of H. pylori infection. The analyser was tested in a prospective multicentre study in 444 patients in North America (Phase 1) followed by second study involving 160 patients (Phase 2). METHODS: Patients undergoing endoscopy for clinical indications had antral and gastric biopsies taken for histological examination, culture and CLO test. One hour after endoscopy, a baseline breath sample was obtained, 100 mg of 13C-urea were ingested and breath samples were obtained at 30 and 60 min post ingestion. Data obtained with the LARA were compared with the results of culture, rapid urease testing and central pathology in two different combinations {reference standards}. The study was conducted in two phases: in Phase 2, a modification was made to the LARA that improved the removal of water vapour from the breath sample. RESULTS: In Phase I, data from 331 patients were analysed using a cut off of (delta) 7.8 +/- 0.8, the sensitivity of the method was 91.7% and the specificity was 86.5%, using the reference standard of 2 of 3 tests (CLO, culture or histology) being positive. Positive and negative predictive values were, respectively, 85.2% and 92.5%. In Phase 2 of the study, 160 patients were enrolled and 141 patients were analysed using the same standards. We used the same reference standards but with a cut off of (delta) 6.1 +/- 0.6. The sensitivity and specificity increased to 96.8% and 98.6%, respectively. Positive and negative predictive values were, respectively, 98.4% and 97.3%. The detection rates for H. pylori were similar in patients with peptic ulcer or H. pylori associated gastritis. CONCLUSIONS: The LARA provides an accurate non-invasive means of detecting 13CO2 in the 13C-urea breath test for H. pylori in a multicentre clinical environment that compares well with invasive 'gold standard' methods.

Seasonal variations in the clinical of presentation of Crohn's disease and ulcerative colitis.

Epidemiological evidence that Crohn's disease could be a transmissible condition is limited. The case histories of 211 patients with Crohn's disease and 201 patients with ulcerative colitis have been scrutinized to ascertain whether there is a seasonal variation in the onset of symptomatic disease. Crohn's disease has a peak onset in January and July whereas ulcerative colitis has a possible peak of onset in December. A hypothesis is proposed that these findings provide epidemiological evidence, suggesting that Crohn's disease could be a transmissible condition, and that Crohn's disease and ulcerative colitis may not be aetiologically related.

Complete intraoperative small-bowel endoscopy in the evaluation of occult gastrointestinal bleeding using the sonde enteroscope.

OBJECTIVE: To review our experience with intraoperative small-bowel Sonde enteroscopy in evaluating occult bleeding in the small intestine. DESIGN: Retrospective study with 100% follow-up. SETTING: University-affiliated, tertiary-care teaching hospital. PATIENTS: Sixteen consecutive patients referred with occult gastrointestinal bleeding in whom esophagogastro-duodenoscopy , push enteroscopy, and colonoscopy had failed to identify the source of bleeding. Fourteen of the 16 patients had required one or more transfusions. MAIN OUTCOME MEASURE: Completeness of visualization, diagnostic accuracy, and complications of the procedure and follow-up for recurrent bleeding. RESULTS: In all 16 patients, intraoperative Sonde enteroscopy allowed visualization of the entire small bowel. In 14 of the 16, it revealed the cause of bleeding, which was ileal angiodysplasia in three patients, ileal ulcers in six patients, neoplasia in two patients, and ileal ulcers caused by Crohn's disease, small-intestinal enteropathy and varices caused by portal hypertension, and radiation stricture in one patient each. Two patients had normal small bowel mucosa. The patients with mucosal disease underwent small-bowel resection or oversewing of bleeding sites. Two surgical complications occurred: prolonged postoperative ileus (one patient) and small-bowel obstruction that resolved without surgery (one patient). Two of the patients with angiodysplasia had recurrent bleeding postoperatively. CONCLUSIONS: Intraoperative Sonde enteroscopy is safe and effective in localizing small-intestinal bleeding sites, providing complete visualization of the small-bowel mucosa without enterotomy while avoiding the trauma that can be caused by push endoscopy. It is the diagnostic assessment of choice in selected patients with occult gastrointestinal bleeding of presumed small-bowel origin.

Use of diagnostic cluster methodology for therapeutic costing and drug surveillance of HMG-CoA reductase-inhibitor therapy.

Diagnostic cluster methodology groups patients having similar medical conditions according to their International Classification of Diseases, 9th Revision codes. Episodes of care related to the diagnostic cluster can then be tracked from the claims data to determine the total charges associated with patient management. A retrospective claims analysis using an episode registry database was conducted to determine the 1-year (July 1, 1995, to June 30, 1996) covered charge for statin therapy, the overall cost of treating related cardiovascular (CV) disease, and the cost impact of coadministration of drugs that potentially compete for hepatic metabolism. The three statin treatment groups (lovastatin, pravastatin, and simvastatin) were similar with respect to age, gender, mean number of prescription refills, rate of refill compliance, and prevalence of the coadministration of potentially interacting agents. Before adjustment for severity of illness, there were no significant differences between groups in prescription drugs/services (statin Rx/Svc) or total CV charges. After adjustment for severity of illness, the pravastatin group had the lowest statin Rx/Svc and total CV charges. Within the group with the greatest severity of illness, statin Rx/Svc charges were significantly lower with pravastatin than with lovastatin and simvastatin. The statin Rx/Svc charges were not significantly different between lovastatin and simvastatin. Coadministration of a potentially interacting agent significantly increased both the statin Rx/Svc and total CV charges within the simvastatin-treated group but did not significantly influence costs in the lovastatin- or pravastatin-treated groups. The estimates of direct costs derived from this analysis are consistent with findings in the published literature and demonstrate that pravastatin has cost advantages compared with lovastatin and simvastatin. Diagnostic cluster methodology also generated valuable information regarding drug surveillance and the health care cost impact of potential drug-drug interactions with selected statins.

Intraoperative enteroscopy. Indications and techniques.

This article reviews the role on intraoperative enteroscopy (IOE) in the management and evaluation of patients with chronic transfusion-dependent gastrointestinal bleeding who have not responded to standard diagnostic and therapeutic techniques. Intraoperative enteroscopy may be performed with a standard or pediatric colonoscope, push enteroscope, or a sonde enteroscope at the time of laparotomy. IOE techniques as well as indications, diagnostic and therapeutic capabilities, and complications of this procedure are discussed.