Weissella confusa: an unexpected cause of vancomycin-resistant gram-positive bacteremia in immunocompromised hosts.

We report the first case of Weissella confusa bacteremia in an allogeneic hematopoietic stem cell transplant patient. After engraftment and discharge, the patient returned with fever and graft failure and was started on an empiric regimen of aztreonam and vancomycin. A blood culture grew an alpha-hemolytic, gram-positive coccus forming pairs and chains, originally thought to be a viridans Streptococcus and a skin contaminant. The isolation of the organism from multiple blood cultures, and the presence of vancomycin resistance prompted identification and additional susceptibility testing. The RapID(™) Str panel, which has W. confusa in its database, provided multiple incorrect identifications. The MicroScan WalkAway 96 SI, using PC-20 or -29 panels, also did not identify this bacterium, because it is not in their database. The organism was identified as W. confusa by 16S rDNA sequencing. Antibiotic susceptibility determination by Etest revealed vancomycin resistance and daptomycin susceptibility. Therapy was changed to daptomycin, and the infection resolved. Additionally, W. confusa sepsis, with multiple positive blood cultures, developed in a patient in the burn unit at our medical center. The patient's blood cultures remained positive until vancomycin was discontinued and daptomycin therapy initiated. Infections with vancomycin-resistant, gram-positive cocci are emerging among immuno compromised hosts. Under appropriate circumstances, clinicians need to request that the laboratory perform susceptibility testing and accurate identification, by nucleic acid sequencing if necessary. Sequencing of 16S rDNA is an important tool in the accurate identification of unusual pathogens.

Sociodemographic factors associated with participation by HIV-1-positive pregnant women in an intervention to prevent mother-to-child transmission of HIV in Cote d'Ivoire.

Many HIV-1-seropositive women in Africa who are offered antiretroviral prophylaxis to prevent mother-to-child transmission (MTCT) of HIV do not begin interventions. Research on barriers to participation has not addressed the possible effects of women's sociocultural and economic circumstances. We examined these factors at an MTCT prevention programme in Abidjan, Cote d'Ivoire. We interviewed two groups of women after they had received HIV-positive test results and had been invited by the programme staff to return for monthly follow-up visits before beginning short-course zidovudine prophylaxis. Participants (n = 30) completed follow-up visits and prophylaxis. Non-participants (n = 27) refused or discontinued follow-up visits and did not begin zidovudine. Fewer non-participants had been born in Cote d'Ivoire (67% vs. 97%) or were Ivorian nationals (48% vs. 77%); they had lived in the country for less time (21 vs. 26 median years). They were less likely to be French-literate (37% vs. 77%), and more of them reported having had Koranic education only (18% vs. 0). They more often reported miscarriages, stillbirths, or infant deaths (69% vs. 33%), and had partners with low-ranked jobs (63% vs. 30%). Our findings suggest that the non-participants were more marginal socioculturally and economically in Ivorian society than participants. Greater attention to mitigating the effects of broader structural factors on women's participation in interventions may increase the effectiveness of MTCT prevention in Africa.

Voluntary counseling and testing for couples: a high-leverage intervention for HIV/AIDS prevention in sub-Saharan Africa.

Most HIV infections in sub-Saharan Africa occur during heterosexual intercourse between persons in couple relationships. Women who are infected by HIV seropositive partners risk infecting their infants in turn. Despite their salience as social contexts for sexual activity and HIV infection, couple relationships have not been given adequate attention by social/behavioral research in sub-Saharan Africa. Increasingly studies point to the value of voluntary HIV counseling and testing (VCT) as a HIV prevention tool. Studies in Africa frequently report that VCT is associated with reduced risk behaviors and lower rates of seroconversion among HIV serodiscordant couples. Many of these studies point out that VCT has considerable potential for HIV prevention among other heterosexual couples, and recommend that VCT for couples be practiced more widely in Africa. However, follow-up in the area of VCT for couples has been extremely limited. Thus, current understandings from social/behavioral research on how couples in sub-Saharan Africa manage HIV risks as well as HIV prevention interventions to support couples' HIV prevention efforts have remained underdeveloped. It appears that important opportunities are being missed for preventing HIV infection, be it by heterosexual transmission or mother-to-child HIV transmission by mothers who have been infected by their partners. Based on an overview of documentation on VCT in sub-Saharan Africa, this paper proposes that increased attention to couples-focused VCT provides a high-leverage HIV prevention intervention for African countries. The second half of the paper indicates areas where VCT needs to be strengthened, particularly with respect to couples. It also identifies areas where applied social/behavioral research is needed to improve knowledge about how couples in sub-Saharan Africa deal with the risks of HIV infection.

A 1.5 hour procedure for identification of Enterococcus Species directly from blood cultures.

Enterococci are a common cause of bacteremia with E. faecalis being the predominant species followed by E. faecium. Because resistance to ampicillin and vancomycin in E. faecalis is still uncommon compared to resistance in E. faecium, the development of rapid tests allowing differentiation between enterococcal species is important for appropriate therapy and resistance surveillance. The E. faecalis OE PNA FISH assay (AdvanDx, Woburn, MA) uses species-specific peptide nucleic acid (PNA) probes in a fluorescence in situ hybridization format and offers a time to results of 1.5 hours and the potential of providing important information for species-specific treatment. Multicenter studies were performed to assess the performance of the 1.5 hour E. faecalis/OE PNA FISH procedure compared to the original 2.5 hour assay procedure and to standard bacteriology methods for the identification of enterococci directly from a positive blood culture bottle.

Secretory immunoglobulin A blocks hypoxia-augmented bacterial passage across Madin-Darby canine kidney cell monolayers.

OBJECTIVE: To study the relative impact of previous hypoxic exposure and the addition of secretory immunoglobulin A (IgA) on bacterial translocation. DESIGN: In vitro randomized experimental study. MATERIALS AND METHODS: Transfected Madin-Darby canine kidney epithelial cells were grown as monolayers in a two-chamber tissue culture system. Stationary growth phase Escherichia coli M14 were inoculated in the apical chamber with medium or medium containing polymeric secretory IgA. Tissue culture dishes were then placed in a 21 or 5% O2 incubator environment for 90 minutes followed by a 21% O2 environment. Medium from the basal compartment was then obtained at timed intervals for bacterial culture. MEASUREMENT AND MAIN RESULTS: Bacterial translocation increased with time in co-culture. Previous hypoxic exposure augmented translocation across the monolayers. The addition of IgA blocked translocation under both normoxic and hypoxic conditions. CONCLUSION: Secretory IgA is important in mucosal defense under both normal and shock conditions.