Evaluation of platelets prepared by apheresis and stored for 5 days. In vitro and in vivo studies

To evaluate the effect of storage on apheresis platelets collected with a closed-system blood cell separator, an in vitro investigation was performed, with measurements of pH, lactate, ATP, the ratio of ATP to the total adenine nucleotide content, and adenylate kinase. Unmodified apheresis platelets and apheresis platelets with plasma added were compared with conventional platelets stored in PL-1240 or PL-732 plastic containers. During 6 days of storage, there were similar changes in all variables with one exception: the extracellular activity of adenylate kinase was lower in apheresis platelets with plasma than in the other three groups (p less than 0.01). In vivo studies were carried out with 111Indium-labeled autologous platelets in eight volunteers. Apheresis platelets with 100 mL of plasma added were stored in two 1000-mL containers (PL-732) at 22 degrees C during agitation. Platelets from one of the containers were labeled with 111Indium and transfused into the volunteer within 24 hours. Platelets from the other container were labeled after 5 days of storage and transfused into the same donor. There were no significant differences between apheresis platelets stored for 1 day and those stored for 5 days: the mean percentage of recovery was 58.4 and 57.6 percent, t1/2 was 69 and 67 hours, and the survival time was 5.5 and 5.6 days, respectively.     

Phenotypic and genotypic characterization of VanA Enterococcus isolated during the first nosocomial outbreak in Brazil

We report the phenotypic and genotypic characterization of 50 VanA Enterococcus clinical isolates from infected patients and 97 isolates from colonized patients obtained during a nosocomial outbreak in a single hospital in S?o Paulo, Brazil during 1998. The identification of strains to the species level by conventional biochemical and phenotypic tests and by multiplex PCR assay had 100% agreement. Both E. faecalis and E. faecium were isolated from patients during this outbreak. The vanA genotype was confirmed by PCR. Antibiotic susceptibility testing showed that E. faecium isolates are generally less susceptible to antibiotics than E. faecalis. By PCR, 24 of 26 VRE strains tested carried the Tn1546 element. Pulsed-field gel electrophoresis identified five distinct patterns for E. faecalis (A, B, C, D, E) and three for E. faecium (M, N, and O). A single PFGE pattern was identified in the majority of strains of each species and does not discriminate between case and carrier isolates.     

Characterization of Small ColE-Like Plasmids Mediating Widespread Dissemination of the qnrB19 Gene in Commensal Enterobacteria

In this work, we have characterized two small ColE-like plasmids (pECY6-7, 2.7 kb in size, and pECC14-9, of 3.0 kb), encoding the QnrB19 quinolone resistance determinant, that were carried by several clonally unrelated quinolone-resistant commensal Escherichia coli strains isolated from healthy children living in different urban areas of Peru and Bolivia. The two plasmids are closely related to each other and carry the qnrB19 gene as the sole resistance determinant, located in a conserved genetic context between the plasmid RNAII sequence (which controls plasmid replication) and the plasmid Xer site (involved in plasmid dimer resolution). ISEcp1-like or other putative insertion sequences are not present in the qnrB19-flanking regions or elsewhere on the plasmids. Since we previously observed a high prevalence (54%) of qnrB genes in the metagenomes of commensal enterobacteria from the same population of healthy children, the presence of pECY6-7- and pECC14-9-like plasmids in those qnrB-positive metagenomes was investigated by PCR mapping. Both plasmids were found to be highly prevalent (67% and 16%, respectively) in the qnrB-positive metagenomes, suggesting that dissemination of these small plasmids played a major role in the widespread dissemination of qnrB genes observed in commensal enterobacteria from healthy children living in those areas.Qnr proteins are small pentapeptide repeat proteins that bind and protect type II DNA topoisomerases from inhibition by fluoroquinolones (29-31). They represent the first discovered transferable mechanism of resistance to quinolones, and their dissemination has been associated with the increase of fluoroquinolone resistance rates in clinical isolates of the Enterobacteriaceae (17, 24). qnr-carrying isolates have been reported worldwide (17, 24), and five different lineages of Qnr proteins have been described so far: QnrA, QnrB, QnrS, and more recently QnrC and QnrD (6, 15, 17, 32).In previous studies, we have observed a remarkable rate of quinolone resistance in commensal Escherichia coli from healthy children living in urban areas of Peru and Bolivia (1) and a high prevalence of qnrB genes (mostly qnrB19) in commensal enterobacteria from the same population of healthy children (19).In this work, we have characterized two small ColE-like plasmids encoding QnrB19, carried by several clonally unrelated quinolone-resistant commensal E. coli strains isolated from children living in different areas, and we have demonstrated that the dissemination of those plasmids apparently played a major role in the widespread dissemination of qnrB genes observed in commensal enterobacteria from that population.(These results were presented in part at the joint 48th Interscience Conference on Antimicrobial Agents and Chemotherapy/46th Annual Meeting of the Infectious Diseases Society of America, Washington, DC, 2008, and at the 19th European Congress of Clinical Microbiology and Infectious Diseases, Helsinki, Finland, 2009.)     

Role of Mycobacterium xenopi disease in patients with HIV infection at the time of highly active antiretroviral therapy (HAART). Comparison with the pre-Haart period

BACKGROUND AND SETTING: A reliable and timely clinical, radiological, and bacteriological diagnosis, and an optimal treatment of non-tubercular mycobacteriosis (including Mycobacterium xenopi disease), remain an unanswered challenge for clinicians facing immunocompromised patients, including those with HIV infection. OBJECTIVE: The aim of our survey is to report the frequency, and the epidemiological, immunological, microbiological, clinical, and therapeutic features of all confirmed HIV-associated M. xenopi disease observed from 1993-2002, with special attention paid to eventual differences that emerged after the introduction of potent antiretroviral therapy (highly active antiretroviral therapy, HAART), on the basis of an international literature update. DESIGN AND RESULTS: Our series of 17 consecutive confirmed M. xenopi infections retrieved in 14 out of 3000 patients followed for HIV disease complications raises a broad series of clinical, diagnostic, therapeutic, and prophylactic concerns. The great majority of M. xenopi disease involved the lower respiratory tract, but atypical features including cavitation and prominent exudative features became apparent in patients successfully treated with HAART, pointing out the possible role of the so-called immune reconstitution syndrome in these episodes. CONCLUSIONS: Diagnostic problems represented by late or missed identification due to slow culture and frequently concomitant opportunistic disorders, join therapeutic difficulties due to the unpredictable in vitro antimicrobial susceptibility profile of these organisms, selection of treatment and chemoprophylaxis according with clinical-radiological and microbiological suspicion, and concomitantly administered medications.     

Ascites in acute pancreatitis: not a silent bystander

Background & aimAscites in patients with acute pancreatitis (AP) is understudied although recent literature hints at its evident role in the final outcome. This study was planned to study the characteristics of ascites in patients of AP and its effect on the disease course and outcome.MethodsConsecutive patients of AP were studied and patients with or without ascites were evaluated for the baseline parameters and severity assessment. Ascites was quantified and fluid analyzed for its characteristics. Intraabdominal pressure (IAP) was monitored. The various outcome parameters were compared between the two groups of patients with and without ascites.ResultsOf the cohort of 213 patients, 82 (38.5%) developed ascites. Ascites group had significantly higher rates of organ failure (p = 0.001), necrosis (p=<0.001) and higher severity assessment scores. The ascites group had significantly longer hospital and ICU stay and higher ventilator days compared to the non-ascites group. Mortality was also higher in the ascites group (34.1% vs 8.45; p = 0.001). Majority of patients with ascites had moderate to gross ascites (75.6%), low serum ascites albumin gradient (87.8%) with low amylase levels (71.9%). Sub-group analysis in ascites group showed that patients with fatal outcome had higher rates of moderate to gross ascites, higher baseline IAP and lower reduction in IAP after 48 h. Moderate to gross ascites and grades of intra-abdominal hypertension (IAH) were significant predictors of mortality (AUC – 0.76).ConclusionAP patients with ascites have a more severe disease with poorer outcome. Higher degrees of ascites and IAH grades are significant predictors of mortality.     

Fungal infections in lung transplantation

Lung transplant is a potential life-saving procedure for chronic lung diseases. Lung transplant recipients (LTRs) are at the greatest risk for invasive fungal infections (IFIs) among solid organ transplant (SOT) recipients because the allograft is directly exposed to fungi in the environment, airway and lung host defenses are impaired, and immunosuppressive regimens are particularly intense. IFIs occur within a year of transplant in 3–19% of LTRs, and they are associated with high mortality, prolonged hospital stays, and excess healthcare costs. The most common causes of post-LT IFIs are Aspergillus and Candida spp.; less common pathogens are Mucorales, other non-Aspergillus moulds, Cryptococcus neoformans, Pneumocystis jirovecii, and endemic mycoses. The majority of IFIs occur in the first year following transplant, although later onset is observed with prolonged antifungal prophylaxis. The most common manifestations of invasive mould infections (IMIs) include tracheobronchial (particularly at anastomotic sites), pulmonary and disseminated infections. The mortality rate of tracheobronchitis is typically low, but local complications such as bronchomalacia, stenosis and dehiscence may occur. Mortality rates associated with lung and disseminated infections can exceed 40% and 80%, respectively. IMI risk factors include mould colonization, single lung transplant and augmented immunosuppression. Candidiasis is less common than mould infections, and manifests as bloodstream or other non-pulmonary invasive candidiasis; tracheobronchial infections are encountered uncommonly. Risk factors for and outcomes of candidiasis are similar to those of non lung transplant recipients. There is evidence that IFIs and fungal colonization are risk factors for allograft failure due to chronic rejection. Mould-active azoles are frontline agents for treatment of IMIs, with local debridement as needed for tracheobronchial disease. Echinocandins and azoles are treatments for invasive candidiasis, in keeping with guidelines in other patient populations. Antifungal prophylaxis is commonly administered, but benefits and optimal regimens are not defined. Universal mould-active azole prophylaxis is used most often. Other approaches include targeted prophylaxis of high-risk LTRs or pre-emptive therapy based on culture or galactomannan (GM) (or other biomarker) results. Prophylaxis trials are needed, but difficult to perform due to heterogeneity in local epidemiology of IFIs and standard LT practices. The key to devising rational strategies for preventing IFIs is to understand local epidemiology in context of institutional clinical practices.     

Environmental perspectives of COVID-19 outbreaks: A review

The coronavirus disease 2019 (COVID-19) pandemic, caused by the novel virus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), began in December 2019 in China and has led to a global public health emergency. Previously, it was known as 2019-nCoV and caused disease mainly through respiratory pathways. The COVID-19 outbreak is ranked third globally as the most highly pathogenic disease of the twenty-first century, after the outbreak of SARS-CoV and Middle East respiratory syndrome in 2002 and 2012, respectively. Clinical, laboratory, and diagnostic methodology have been demonstrated in some observational studies. No systematic reviews on COVID-19 have been published regarding the integration of COVID-19 outbreaks (monitoring, fate and treatment) with environmental and human health perspectives. Accordingly, this review systematically addresses environmental aspects of COVID-19 outbreak such as the origin of SARS-CoV-2, epidemiological characteristics, diagnostic methodology, treatment options and technological advancement for the prevention of COVID-19 outbreaks. Finally, we integrate COVID-19 outbreaks (monitoring, fate and treatment) with environmental and human health perspectives. We believe that this review will help to understand the SARS-CoV-2 outbreak as a multipurpose document, not only for the scientific community but also for global citizens. Countries should adopt emergency preparedness such as prepare human resources, infrastructure and facilities to treat severe COVID-19 as the virus spreads rapidly globally.     

Role of colonic fermentation in the perception of colonic distention in irritable bowel syndrome and functional bloating.

BACKGROUND & AIMS: Bloating represents a frequent gastrointestinal symptom, but the pathophysiologic mechanism responsible for its onset is still largely unknown. Patients very frequently attribute the sensation of bloating to the presence of excessive bowel gas, but not all patients with gas-related symptoms exhibit increased intestinal production of gas. It is therefore possible that other still unrecognized mechanisms might contribute to its pathophysiology. Our aim was to evaluate whether a subgroup of patients affected by functional abdominal bloating presents hypersensitivity to colonic fermentation. METHODS: Sixty patients affected by functional gastrointestinal disorders (11 functional bloating, 36 constipation-predominant, and 13 diarrhea-predominant irritable bowel syndrome) and moderate to severe bloating took part in the study. Twenty sex- and age-matched healthy volunteers were enrolled as a control group. All the subjects underwent a preliminary evaluation of breath hydrogen excretion after oral lactulose. Then, on a separate day, an evaluation of sensitivity thresholds at rectal level was performed with a barostat before and after the induction of colonic fermentation with oral lactulose. A control test with electrolyte solution was also performed. RESULTS: Both breath hydrogen excretion and mouth-to-cecum transit time did not differ between the 4 groups studied. Neither electrolyte solution nor lactulose modified sensitivity thresholds in healthy volunteers. In low hydrogen producers, basal perception and discomfort thresholds were similar to high hydrogen producers, but after lactulose both perception and discomfort thresholds were significantly reduced only in low hydrogen producers. CONCLUSIONS: A subgroup of patients with functional gastrointestinal disorders and moderate to severe bloating might have hypersensitivity to products of colonic fermentation.