Phenotypic Characterization of AmpC beta-lactamase among Cefoxitin Resistant Escherichia coli and Klebsiella pneumoniae Isolates in Accra, Ghana

AmpC ?-lactamases hydrolyze penicillins, cephalosporins and cephamycins and resist inhibition by clavulanate, sulbactam, and tazobactam. Strains with AmpC genes are inherently resistant to multiple agents, making the selection of an effective antibiotic difficult. This present work sought to investigate the occurrence of AmpC beta-lactamases-producing phenotypes in E. coli and K. pneumoniae and their antimicrobial sensitivity profile. Four hundred K. pneumoniae and E. coli non-duplicate isolates were collected and their antibiotic sensitivity testing for cefoxitin and other 16 antibiotics were determined using Vitek 2 Compact System (bioMérieux, Marcy I’Etoile, France).  The isolates resistant to cefoxitin were confirmed as AmpC beta-lactamases-producing phenotypes with disk synergy testing (DST) using cefotaxime or ceftazidime with or without boronic acid. An increase in zone diameter of ?5mm in the presence of boronic acid indicates the presence of AmpC beta-lactamases in the test organism. The results showed that of the 50 cefoxitin resistant isolates screened from 400 bacterial isolates, 5(10%) were AmpC beta-lactamase-producers with 60%, 60%, 60%, 80% and 100% multiply antibiotic resistance in gentamicin, ciprofloxacin, norfloxacin, trimethoprim/sulfamethoxazole and tetracycline respectively. Nitrofurantoin which indicated 100% susceptibility with MIC90 of 32µg/ml may be a therapeutic option especially for non-life-threatening urinary tract infection. Imipenem was the antibiotic of choice with 100% susceptibility rates (MIC90 of ?1µg/ml). Though the insignificant (p>0.05) levels of AmpC beta-lactamase phenotypes may not require routine detection in health facilities, there is the need to implement evolutionary antibiotic administration policies and pragmatic infection control measures in the hospitals.      Keywords: AmpC beta-lactamase, Cefoxitin, ?-lactams, E. coli, K. pneumonia

The Reliability of Using Vitek 2 Compact System to Detect Extended-Spectrum Beta-lactamase-producing Isolates in Escherichia coli and Klebsiella pneumoniae in Accra, Ghana

Extended-spectrum beta-lactamases (ESBLs) are plasmid-mediated beta-lactamases that are capable of hydrolysing ?-lactams except carbapenems and cephamycins. The global increased prevalence of ESBL-producing bacteria creates an urgent need for laboratory diagnostic methods that will accurately and rapidly identify the presence of ESBL phenotypes in clinical isolates. The Vitek 2 System (bioMérieux, France) is a rapid automated microbiological system used for bacteria and yeast identification, antimicrobial susceptibility testing (AST), resistance mechanism detection and epidemiologic trending and reporting using its advanced expert system. This present work sought to determine the reliability of routinely using Vitek 2 System to accurately and rapidly detect ESBL-producing E. coli and K. pneumoniae in Accra. The ESBL phenotypes for 400 E. coli and K. pneumoniae isolates were determined using the Vitek 2 system and combined disc synergy method. The results were used to determine the sensitivity, specificity, negative predictive value and positive predictive value of the Vitek 2 ESBL test through comparative analysis with the combined disk synergy method which is the reference method recommended by CLSI. The findings of this work indicated that the sensitivity, specificity, positive predictive value and negative predictive value of Vitek 2 system was 98.5%, 98.9%, 99% and 98.5% respectively. Consequently, Vitek 2 system is a reliable semi-automated microbiology system which may be used for routine, accurate and rapid detection of ESBL strains in health facilities in Accra, Ghana. Keywords: Vitek 2 Compact System, Extended spectrum beta-lactamase, bioMérieux, E. coli and K.  pneumoni

Plasmodium yoelii 17XL infection up-regulates RANTES, CCR1, CCR3 and CCR5 expression, and induces ultrastructural changes in the cerebellum

BACKGROUND: Malaria afflicts 300–500 million people causing over 1 million deaths globally per year. The immunopathogenesis of malaria is mediated partly by co mplex cellular and immunomodulator interactions involving co-regulators such as cytokines and adhesion molecules. However, the role of chemokines and their receptors in malaria immunopathology remains unclear. RANTES (Regulated on Activation Normal T-Cell Expressed and Secreted) is a chemokine involved in the generation of inflammatory infiltrates. Recent studies indicate that the degradation of cell-cell junctions, blood-brain barrier dysfunction, recruitment of leukocytes and Plasmodium-infected erythrocytes into and occlusion of microvessels relevant to malaria pathogenesis are associated with RANTES expression. Additionally, activated lymphocytes, platelets and endothelial cells release large quantities of RANTES, thus suggesting a unique role for RANTES in the generation and maintenance of the malaria-induced inflammatory response. The hypothesis of this study is that RANTES and its corresponding receptors (CCR1, CCR3 and CCR5) modulate malaria immunopathogenesis. A murine malaria model was utilized to evaluate the role of this chemokine and its receptors in malaria. METHODS: The alterations in immunomodulator gene expression in brains of Plasmodium yoelii 17XL-infected mice was analysed using cDNA microarray screening, followed by a temporal comparison of mRNA and protein expression of RANTES and its corresponding receptors by qRT-PCR and Western blot analysis, respectively. Plasma RANTES levels was determined by ELISA and ultrastructural studies of brain sections from infected and uninfected mice was conducted. RESULTS: RANTES (p < 0.002), CCR1 (p < 0.036), CCR3 (p < 0.033), and CCR5 (p < 0.026) mRNA were significantly upregulated at peak parasitaemia and remained high thereafter in the experimental mouse model. RANTES protein in the brain of infected mice was upregulated (p < 0.034) compared with controls. RANTES plasma levels were significantly upregulated; two to three fold in infected mice compared with controls (p < 0.026). Some d istal microvascular endothelium in infected cerebellum appeared degraded, but remained intact in controls. CONCLUSION: The upregulation of RANTES, CCR1, CCR3, and CCR5 mRNA, and RANTES protein mediate inflammation and cellular degradation in the cerebellum during P. yoelii 17XL malaria

Elevated Levels of IL-10 and G-CSF Associated with Asymptomatic Malaria in Pregnant Women

In sub-Saharan Africa, approximately 30 million pregnant women are at risk of contracting malaria annually. Nearly 36% of healthy pregnant women receiving routine antenatal care tested positive for Plasmodium falciparum HRP-II antigen in Ghana. We tested the hypothesis that asymptomatic HRP II positive pregnant women expressed a unique Th1 and Th2 phenotype that differs from healthy controls. Plasma from healthy (n = 15) and asymptomatic (n = 25) pregnant women were evaluated for 27 biomarkers (IL-1b, IL-1ra, IL-2, IL-4, IL-5, IL-6, IL-7, IL-8, IL-9, IL-10, IL-12, IL-13, IL-15, IL- 17, Eotaxin, bFGF-2, G-CSF, GM-CSF, IFN-γ, IP-10, MCP-1, MIP-1α, MIP-1β, PDGF-bb, RANTES, TNF, and VEGF) associated with Th1 and Th2 cytokine homeostasis. IL-10 and G-CSF levels were elevated in the asymptomatic group when compared with the healthy group (P = .031 and .041, resp.). The median ratios of IL-1β:5, IL-1β:10, IL-1β:G-CSF, IL-1β:Eotaxin, IL-12:G-CSF, IL-15:10, IL-17:G-CSF, IL-17:Eotaxin, TNF:IL-4, TNF:IL-5, and TNF:G-CSF were significantly different among the two groups. Thus, asymptomatic malaria carriage may be linked to circulating levels of IL-10 and G-CSF

Correlates of HIV, HBV, HCV and syphilis infections among prison inmates and officers in Ghana: A national multicenter study

<p>Abstract</p> <p>Background</p> <p>Prisons are known to be high-risk environments for the spread of bloodborne and sexually transmitted infections. Prison officers are considered to have an intermittent exposure potential to bloodborne infectious diseases on the job, however there has been no studies on the prevalence of these infections in prison officers in Ghana.</p> <p>Methods</p> <p>A national multicenter cross-sectional study was undertaken on correlates of human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV), and syphilis infections in sample of prison inmates and officers from eight of ten regional central prisons in Ghana. A total of 1366 inmates and 445 officers were enrolled between May 2004 and December 2005. Subjects completed personal risk-factor questionnaire and provided blood specimens for unlinked anonymous testing for presence of antibodies to HIV, HCV and <it>Treponema pallidum</it>; and surface antigen of HBV (HBsAg). These data were analyzed using both univariate and multivariate techniques.</p> <p>Results</p> <p>Almost 18% (1336) of 7652 eligible inmates and 21% (445) of 2139 eligible officers in eight study prisons took part. Median ages of inmates and officers were 36.5 years (range 16–84) and 38.1 years (range 25–59), respectively. Among inmates, HIV seroprevalence was 5.9%, syphilis seroprevalence was 16.5%, and 25.5% had HBsAg. Among officers tested, HIV seroprevalence was 4.9%, HCV seroprevalence was 18.7%, syphilis seroprevalence was 7.9%, and 11.7% had HBsAg. Independent determinants for HIV, HBV and syphilis infections among inmates were age between 17–46, being unmarried, being illiterate, female gender, being incarcerated for longer than median time served of 36 months, history of homosexuality, history of intravenous drug use, history of sharing syringes and drug paraphernalia, history of participation in paid sexual activity, and history of sexually transmitted diseases. Independent determinants for HIV, HBV, HCV and syphilis infections among officers were age between 25–46, fale gender, being unmarried, being employed in prison service for longer than median duration of employment of 10 years, and history of sexually transmitted diseases.</p> <p>Conclusion</p> <p>The comparably higher prevalence of HIV, HBV, HCV and syphilis in prison inmates and officers in Ghana suggests probable occupational related transmission. The implementation of infection control practices and risk reduction programs targeted at prison inmates and officers in Ghana is urgently required to address this substantial exposure risk.</p

Phenotypic Determination and Antimicrobial Resistance Profile of Extended Spectrum Beta-lactamases in Escherichia coli and Klebsiella pneumoniae in Accra, Ghana

Extended-spectrum beta-lactamases (ESBLs) are plasmid-mediated beta lactamases commonly found in the Enterobacteriaceae that are capable of hydrolysing ?-lactams except carbapenems and cephamycins. ESBLs confer resistance to several non-ß-lactam antibiotics. ESBL-producing organisms appear susceptible to cephalosporins in vitro using conventional breakpoints but ineffective in vivo. This work sought to determine the occurrence of ESBL in E. coli and K. pneumoniae and their antibiotic resistance profile. Four hundred K. pneumoniae and E. coli non-duplicate isolates were collected at the Central Laboratory of Korle Bu Teaching Hospital and Advent Clinical Laboratories. They were definitively identified and their minimum inhibition concentration and antibiotic sensitivity testing for 17 antibiotics were determined using Vitek 2 Compact System (bioMérieux, Marcy I’Etoile, France).  The isolates were confirmed as ESBL-producing strains using the Combination Disk Synergy Method. The results indicated that 202 (50.5%) of the bacterial isolates were ESBL-producing phenotypes with high resistant to gentamicin, ciprofloxacin, tetracycline and trimethoprim/sulfamethoxazole indicating 82.2%, 79.7%, 70.8% and 97% resistant rates respectively. imipenem and amikacin were the antibiotics of choice with 99% and 94.1% susceptibility rates (MIC90 of ?1µg/ml and 4µg/ml respectively). It is imperative to routinely detect ESBL-phenotypes in health facilities, implement appropriate antibiotic administration policy and infection control measures in the hospitals.   Keywords: Extended Spectrum Beta-lactamase, Antimicrobial Resistance, ?-lactams, K. pneumoniae, E. col

RAGE (Receptor for Advanced Glycation Endproducts), RAGE Ligands, and their role in Cancer and Inflammation

The Receptor for Advanced Glycation Endproducts [RAGE] is an evolutionarily recent member of the immunoglobulin super-family, encoded in the Class III region of the major histocompatability complex. RAGE is highly expressed only in the lung at readily measurable levels but increases quickly at sites of inflammation, largely on inflammatory and epithelial cells. It is found either as a membrane-bound or soluble protein that is markedly upregulated by stress in epithelial cells, thereby regulating their metabolism and enhancing their central barrier functionality. Activation and upregulation of RAGE by its ligands leads to enhanced survival. Perpetual signaling through RAGE-induced survival pathways in the setting of limited nutrients or oxygenation results in enhanced autophagy, diminished apoptosis, and (with ATP depletion) necrosis. This results in chronic inflammation and in many instances is the setting in which epithelial malignancies arise. RAGE and its isoforms sit in a pivotal role, regulating metabolism, inflammation, and epithelial survival in the setting of stress. Understanding the molecular structure and function of it and its ligands in the setting of inflammation is critically important in understanding the role of this receptor in tumor biology

Adjuvant chemotherapy with or without bevacizumab in patients with resected non-small-cell lung cancer (E1505): an open-label, multicentre, randomised, phase 3 trial.

BackgroundAdjuvant chemotherapy for resected early-stage non-small-cell lung cancer (NSCLC) provides a modest survival benefit. Bevacizumab, a monoclonal antibody directed against VEGF, improves outcomes when added to platinum-based chemotherapy in advanced-stage non-squamous NSCLC. We aimed to evaluate the addition of bevacizumab to adjuvant chemotherapy in early-stage resected NSCLC.MethodsWe did an open-label, randomised, phase 3 trial of adult patients (aged ≥18 years) with an Eastern Cooperative Oncology Group performance status of 0 or 1 and who had completely resected stage IB (≥4 cm) to IIIA (defined by the American Joint Committee on Cancer 6th edition) NSCLC. We enrolled patients from across the US National Clinical Trials Network, including patients from the Eastern Cooperative Oncology Group-American College of Radiology Imaging Network (ECOG-ACRIN) affiliates in Europe and from the Canadian Cancer Trials Group, within 6-12 weeks of surgery. The chemotherapy regimen for each patient was selected before randomisation and administered intravenously; it consisted of four 21-day cycles of cisplatin (75 mg/m2 on day 1 in all regimens) in combination with investigator's choice of vinorelbine (30 mg/m2 on days 1 and 8), docetaxel (75 mg/m2 on day 1), gemcitabine (1200 mg/m2 on days 1 and 8), or pemetrexed (500 mg/m2 on day 1). Patients in the bevacizumab group received bevacizumab 15 mg/kg intravenously every 21 days starting with cycle 1 of chemotherapy and continuing for 1 year. We randomly allocated patients (1:1) to group A (chemotherapy alone) or group B (chemotherapy plus bevacizumab), centrally, using permuted blocks sizes and stratified by chemotherapy regimen, stage of disease, histology, and sex. No one was masked to treatment assignment, except the Data Safety and Monitoring Committee. The primary endpoint was overall survival, analysed by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00324805.FindingsBetween June 1, 2007, and Sept 20, 2013, 1501 patients were enrolled and randomly assigned to the two treatment groups: 749 to group A (chemotherapy alone) and 752 to group B (chemotherapy plus bevacizumab). 383 (26%) of 1458 patients (with complete staging information) had stage IB, 636 (44%) had stage II, and 439 (30%) had stage IIIA disease (stage of disease data were missing for 43 patients). Squamous cell histology was reported for 422 (28%) of 1501 patients. All four cisplatin-based chemotherapy regimens were used: 377 (25%) patients received vinorelbine, 343 (23%) received docetaxel, 283 (19%) received gemcitabine, and 497 (33%) received pemetrexed. At a median follow-up of 50·3 months (IQR 32·9-68·0), the estimated median overall survival in group A has not been reached, and in group B was 85·8 months (95% CI 74·9 to not reached); hazard ratio (group B vs group A) 0·99 (95% CI 0·82-1·19; p=0·90). Grade 3-5 toxicities of note (all attributions) that were reported more frequently in group B (the bevacizumab group) than in group A (chemotherapy alone) were overall worst grade (ie, all grade 3-5 toxicities; 496 [67%] of 738 in group A vs 610 [83%] of 735 in group B), hypertension (60 [8%] vs 219 [30%]), and neutropenia (241 [33%] vs 275 [37%]). The number of deaths on treatment did not differ between the groups (15 deaths in group A vs 19 in group B). Of these deaths, three in group A and ten in group B were considered at least possibly related to treatment.InterpretationAddition of bevacizumab to adjuvant chemotherapy did not improve overall survival for patients with surgically resected early-stage NSCLC. Bevacizumab does not have a role in this setting and should not be considered as an adjuvant therapy for patients with resected early-stage NSCLC.FundingNational Cancer Institute of the National Institutes of Health

Sex differences in perceived risk and testing experience of HIV in an urban fishing setting in Ghana

The concept of neighborhood remains important in criminology but there is an increasing academic interest in the potential impact of the Modifiable Areal Unit Problem (MAUP) on neighborhood based studies. In the present study data over arson from the Swedish rescue services 2007-2012 have been employed to analyze MAUP in the city of Malmö, Sweden. The city has been divided into 50*50 meter pixels as micro-places (n=64540) which have been assigned a value for arson from frequency of arson within the pixel. The analysis is based on a comparison of two types of administrative geographical units alongside 40 randomly generated sets of thiessen polygon geographical units. Empty two-level hierarchical regression models with the micro-places as level 1 unit have been used to calculate Intra-Class Correlations (ICC) separately with each of the 42 different geographical units of analysis as level 2 units. The analysis is repeated with two alternative methods, kernel density and euclidian distance, to calculate a value for each micro-place. Results show that administrative geographical units of analysis in some cases just are marginally better than geographical units with random boundaries if the basic urban structure is taken into account