Increasing Bacteremia Due to Coagulase-Negative Staphylococci: Fiction or Reality?

Abstract BACKGROUND: The role of coagulase-negative staphylococci (CNS) in bacteremias continues to be controversial. Until the 1970s, CNS were mostly recognized as contaminants, being part of the cutaneous flora. Since then, several studies have reported increasing incidence and severity of infections due to CNS. PURPOSE: To review the literature concerning the epidemiology of CNS bacteremia in the United States and Europe with reference to the multiple definitions of infection versus contamination, considering the effect of potential biases influencing the validity of the reported results. METHODS: Literature search of the MEDLINE database from January 1980 to February 1998. Studies with fewer than 500 episodes of bloodstream infections or fewer than 100 episodes of CNS bacteremia were not included in the pooled analysis. RESULTS: (1) CNS remain the most frequent contaminants (58%-83% of positive blood cultures); (2) the proportion of all bloodstream infections caused by CNS is increasing (R=.51); (3) the overall incidence of true CNS bacteremia is increasing (R=.54, P=.0014); (4) comparing the United States to Europe, there is an increasing trend in the incidence of nosocomial bacteremia due to CNS in the United States (R=.82, P=.0006), but no trend is seen in European studies; (5) the mortality associated with true CNS bacteremia varies between 4.9% and 28%. DISCUSSION: This review confirms the increasing importance of CNS bacteremias, measured both as a proportion and as an incidence of bloodstream infections. The contributions of several possible explanations for the incidence increase and the difference between the United States and Europe need further evaluation: (1) increased recognition and awareness of CNS infections among clinicians; (2) a gradual change in the definition of true bacteremia from an obligatory two positive blood cultures to one positive blood culture associated with a clinical picture compatible with infection; (3) a change in blood culture practices and techniques; (4) an increase in the numbers of blood cultures performed, which is reported both in the United States and in Europe; (5) a shift toward more elderly patients with increasingly severe underlying illnesses; and (6) increasing use of intravascular devices. CONCLUSIONS: The apparent trend of increasing CNS bacteremia seems to be valid. Whether there is a real difference between the United States and Europe concerning the increase of CNS bacteremia is difficult to establish due to the large number of confounding factors. Few studies take into account the number of blood cultures performed or the use of intravascular devices to adjust for the observed trends. Further on-site surveillance studies are needed to investigate the phenomenon more extensivel

Endogenous bioelectric currents promote differentiation of the mammalian lens

Acknowledgements We are grateful to Kevin S. Mackenzie in our imaging core facility. This work was supported by the University of Aberdeen (at which the majority of the experimental work was conducted). The work was supported by Action Medical Research (GN2299) and Fight for Sight (RG13315-10).Peer reviewedPublisher PD

Official Vodou and Vodou Churches in Haiti: The Vodou conquest of the public sphere

The last decades have seen some new trends within Haitian Vodou such as the first formal Vodou organizations of the eighties, the 2003 presidential decree officially recognizing Vodou as a religion, as well as attempts to ‘structure’, and ‘homogenize’ Vodou on a nationwide scale. This paper explores another, yet related, item among such transformations: namely, public discourse on, and aspirations to create, Vodou churches, marriages, baptisms, and funerals. In this article, such phenomena are foremost interpreted as attributes of the social status and legitimacy of ‘serious religion’ and as having less to do with purely spiritual, or religious, matters. The actual need for such additions—at least, in realized form—however, is less tangible among Vodou practitioners. Here it is suggested that this situation explains why so few Vodou churches are actually established, or marriages celebrated. It is also proposed that through the  mere act of entering the public sphere and making their claims heard, Vodou practitioners to a large extent have already rendered the Vodou religion legitimate.   Keywords: Haiti, Vodou, the official recognition of Haitian Vodou, marriages, baptisms and funerals

Surgical interventions for age-related cataract.

BACKGROUND: Cataract is the major cause of global blindness, accounting for 40 to 80% of all blindness in developing countries. The number of people blind from cataract is expected to rise due to the changing age distribution and increasing life expectancy. There is currently no proven intervention to prevent cataract and surgery is the only form of treatment. OBJECTIVES: The objective of this review is to compare the effects of different surgical interventions for age-related cataract. SEARCH STRATEGY: We searched the Cochrane Controlled Trials Register - CENTRAL/CCTR, which contains the Cochrane Eyes and Vision Group specialised register (Cochrane Library Issue 3 2001), MEDLINE (1966 to August 2001), EMBASE (1980 to September 2001), the reference lists of identified trials, and we contacted investigators and experts in the field for details of published and unpublished trials. SELECTION CRITERIA: We included randomised controlled trials evaluating surgical treatment for people with age-related cataract. DATA COLLECTION AND ANALYSIS: Two reviewers independently extracted data and discrepancies were resolved by discussion. Where appropriate, relative risks, odds ratios and weighted mean differences were summarised after assessing heterogeneity between the studies. We used a fixed effect model due to the low number of trials in each comparison. MAIN RESULTS: We identified six trials that randomised a total of 7828 people. Phacoemulsification gave a better visual outcome than extracapsular surgery and gave a similar average cost per procedure in one trial conducted in the UK. Extracapsular surgery with posterior chamber lens implant and intracapsular surgery with or without an anterior chamber intraocular lens implant gave acceptable visual outcomes at 12 to 24 months after surgery. In three large trials in south Asia, best-corrected visual acuity of less than 6/60 ranged from 0.5 to 4%. Higher rates of poor outcome were observed in a multicentre study with 19 surgeons compared to a single-centre study with two surgeons. REVIEWER'S CONCLUSIONS: This review provides evidence from one randomised controlled trial that phacoemulsification gives a better visual outcome than extracapsular extraction with sutures. However, this trial was conducted in a developed country specialised hospital setting and extrapolation to other settings must be made with caution. This review also found evidence that extracapsular cataract extraction with a posterior chamber lens implant provides better visual outcome than intracapsular extraction with aphakic glasses. This finding is also based on the results of a single trial. The long term effects of posterior capsular opacification need to be assessed in larger populations. The data in the review suggest that intracapsular extraction with an anterior chamber lens implant is an effective alternative to intracapsular extraction with aphakic glasses, with similar safety. Further data from developing regions are needed to compare all aspects of intraocular lens surgery with the three main surgical procedures - intracapsular extraction with an anterior chamber lens, extracapsular surgery with a posterior chamber lens with or without sutures

Growth factor restriction impedes progression of wound healing following cataract surgery: identification of VEGF as a putative therapeutic target

Secondary visual loss occurs in millions of patients due to a wound-healing response, known as posterior capsule opacification (PCO), following cataract surgery. An intraocular lens (IOL) is implanted into residual lens tissue, known as the capsular bag, following cataract removal. Standard IOLs allow the anterior and posterior capsules to become physically connected. This places pressure on the IOL and improves contact with the underlying posterior capsule. New open bag IOL designs separate the anterior capsule and posterior capsules and further reduce PCO incidence. It is hypothesised that this results from reduced cytokine availability due to greater irrigation of the bag. We therefore explored the role of growth factor restriction on PCO using human lens cell and tissue culture models. We demonstrate that cytokine dilution, by increasing medium volume, significantly reduced cell coverage in both closed and open capsular bag models. This coincided with reduced cell density and myofibroblast formation. A screen of 27 cytokines identified nine candidates whose expression profile correlated with growth. In particular, VEGF was found to regulate cell survival, growth and myofibroblast formation. VEGF provides a therapeutic target to further manage PCO development and will yield best results when used in conjunction with open bag IOL designs

Interventions for trachoma trichiasis.

BACKGROUND: Trachoma is a leading cause of avoidable blindness. The World Health Organization recommends eliminating trachoma blindness by the SAFE strategy incorporating Surgery, Antibiotic treatment, Facial cleanliness and Environmental hygiene. OBJECTIVES: This review examined the evidence for the effectiveness of different interventions for trachoma trichiasis. SEARCH STRATEGY: We identified trials from the Cochrane Central Register of Controlled Trials (CENTRAL) on The Cochrane Library (2005, Issue 3), MEDLINE (1966 to September 2005) PubMed (searched on 21-09-06; last 90 days), EMBASE (1980 to September 2005), LILACS (March 2004) and the reference lists of included studies. We also contacted authors for details of other relevant studies. SELECTION CRITERIA: We included randomised trials of any intervention intended to treat trachoma trichiasis and trials comparing different methods of delivering the same intervention. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed trials. We contacted trial authors for missing data when necessary. MAIN RESULTS: Seven studies met the inclusion criteria. Three studies compared different surgical interventions. These trials suggest the most effective surgery is full-thickness incision of the tarsal plate and rotation of the terminal tarsal strip 180 degrees. One study showed that bilamellar rotation was more effective than unilamellar rotation but the other two studies did not. One trial found double-sided sticking plaster more effective than epilation for the immediate management of trichiasis but required frequent replacement (odds ratio (OR) 0.01, 95% confidence interval (CI) 0.00 to 0.22). Another trial found community-based surgery increased convenience for patients without increasing the risk of complications or recurrence when compared to health centres. One trial found no difference between trichiasis surgery performed by ophthalmologists and integrated eye workers (OR 1.32, 95% CI 0.83 to 2.11). A trial comparing trichiasis surgery with and without concurrent administration of azithromycin found no difference in success rates at one year (OR 0.99, 95% CI 0.67 to 1.46). AUTHORS' CONCLUSIONS: No trials show interventions for trichiasis prevent blindness. Certain interventions have been shown to be more effective at eliminating trichiasis. Full thickness incision of the tarsal plate and rotation of the lash-bearing lid margin through 180 degrees is probably the best technique and is preferably delivered in the community. The use of double-sided sticking plaster is more effective than epilation as a temporary measure. Surgery may be carried out by an ophthalmologist or a trained ophthalmic assistant. The addition of azithromycin treatment at the time of surgery does not appear to improve outcomes

Elimination of onchocerciasis in Ecuador: findings of post-treatment surveillance.

BACKGROUND: The Esmeraldas focus of onchocerciasis in Ecuador expanded geographically during the 1980s and was associated with severe ocular and skin disease. Mass drug administration (MDA) with ivermectin started in 1991, initially once but later twice a year, in the principle endemic focus followed by all satellite foci. Treatment was stopped in 2009 when entomological assessments determined that transmission of Onchocerca volvulus had been interrupted. METHODS: Three years after the cessation of ivermectin treatment in 2012, as defined by the WHO guidelines for onchocerciasis elimination, blackfly collections were done in four sentinel sites in former hyperendemic areas. The presence of infective larvae in local vectors, Simulium exiguum and Simulum quadrivittatum, was assessed by detection of O. volvulus DNA by PCR. Additional flies captured in four extra-sentinel sites located in former hyper- and mesoendemic dispersed isolated areas were also assessed. RESULTS: The results from 68,310 captured blackflies, 40,114 from four sentinel villages in the previously hyperendemic areas (Corriente Grande, El Tigre, San Miguel on Río Cayapas and Naranjal on Río Canandé) and 28,197 from extra-sentinel locations, were all negative for the presence of O. volvulus. These extra-sentinel sites (Hualpí on Río Hoja Blanca, Capulí on Río Onzole, La Ceiba on Río Tululví and Medianía on Río Verde) were included to provide additional evidence of the impact of MDA on the transmission of O. volvulus in isolated endemic areas. CONCLUSIONS: Our data indicate that transmission of O. volvulus has been stopped in all endemic areas in Ecuador, including all satellite foci outside the main focus. These findings indicate that a strategy of ivermectin distribution twice a year to over 85% of the treatment-eligible population was effective in eliminating the infection from Ecuador in a focus with a highly competent primary vector, S. exiguum, and where the infection rates were equal to or greater than observed in many onchocerciasis foci in Africa

CT694 and pgp3 as Serological Tools for Monitoring Trachoma Programs.

Defining endpoints for trachoma programs can be a challenge as clinical signs of infection may persist in the absence of detectable bacteria. Antibody-based tests may provide an alternative testing strategy for surveillance during terminal phases of the program. Antibody-based assays, in particular ELISAs, have been shown to be useful to document C. trachomatis genital infections, but have not been explored extensively for ocular C. trachomatis infections. An antibody-based multiplex assay was used to test two C. trachomatis antigens, pgp3 and CT694, for detection of trachoma antibodies in bloodspots from Tanzanian children (n = 160) collected after multiple rounds of mass azithromycin treatment. Using samples from C. trachomatis-positive (by PCR) children from Tanzania (n = 11) and control sera from a non-endemic group of U.S. children (n = 122), IgG responses to both pgp3 and CT694 were determined to be 91% sensitive and 98% specific. Antibody responses of Tanzanian children were analyzed with regard to clinical trachoma, PCR positivity, and age. In general, children with more intense ocular pathology (TF/TI = 2 or most severe) had a higher median antibody response to pgp3 (p = 0.0041) and CT694 (p = 0.0282) than those with normal exams (TF/TI = 0). However, 44% of children with no ocular pathology tested positive for antibody, suggesting prior infection. The median titer of antibody responses for children less than three years of age was significantly lower than those of older children. (p<0.0001 for both antigens). The antibody-based multiplex assay is a sensitive and specific additional tool for evaluating trachoma transmission. The assay can also be expanded to include antigens representing different diseases, allowing for a robust assay for monitoring across NTD programs