What’s old is new again:Insights into diabetic foot microbiome

Diabetes is a chronic disease that is considered one of the most stubborn global health problems that continues to defy the efforts of scientists and physicians.The prevalence of diabetes in the global population continues to grow to alarming levels year after year,causing an increase in the incidence of diabetes complications and health care costs all over the world.One major complication of diabetes is the high susceptibility to infections especially in the lower limbs due to the immunocompromised state of diabetic patients,which is considered a definitive factor in all cases.Diabetic foot infections continue to be one of the most common infections in diabetic patients that are associated with a high risk of serious complications such as bone infection,limb amputations,and life-threatening systemic infections.In this review,we discussed the circumstances associated with the high risk of infection in diabetic patients as well as some of the most commonly isolated pathogens from diabetic foot infections and the related virulence behavior.In addition,we shed light on the different treatment strategies that aim at eradicating the infection.

Nosocomial spread of hospital-adapted CC17 vancomycin-resistant Enterococcus faecium in a tertiary-care hospital of Beijing, China

Background The incidence of vancomycin-resistant enterococci （VRE） appeared to be increasing in China, but very few nosocomial outbreaks have been reported. Our hospital had experienced an outbreak of VRE since March 2008 to March 2009. The objective of this study was to analyze the molecular features of the isolates and the control measures used to eradicate a VRE outbreak in a tertiary institution in China.Methods We characterized VRE isolates from 21 infected and 11 colonized inpatients from a single hospital by pulsed field gel electrophoresis （PFGE）, multilocus sequence typing （MLST）, the analysis of Tn 1546-like elements and virulence genes detection. Infection control measures, including more environmental disinfection, screening for VRE colonization,contact precautions, education and strict antibiotic restriction, were implemented to control the outbreak.Results During the outbreak, a total of 32 VRE strains were obtained. There were 21 strains found in Emergency Intensive Care Unit （EICU）, 9 isolates from Geriatric Ward, and two from other units. All the isolates harbored the vanA gene, however,four of them exhibited the VanB phenotype. Meanwhile, MLST analysis revealed that all isolates belonged to clonal complex （CC） 17. With the infection-control measures, the epidemic was constrained in two units （EICU and Geriatric Ward）. After March 2009, no further case infected with VRE was detected in the following one-year period.Conclusion The outbreak was controlled by continuous implementation of the infection control programme, and more rigorous infection control policy is needed.

Antibacterial activity of selected marine macro algae against vancomycin resistant Enterococcus faecalis

Objective:To evaluate the antibacterial activity of different extracts of Caulerpa chemnitzia(Epser)J.V.Lamououx,Caulerpa racemosa(Frosk.)Weber-van-Bosse(C.racemosa),Caulerpa scalpelliformis(R.Br.)Weber-van-Bosse,Ulva lactuca Lin,Ulva fasciata Dellie,Ulva reticulata Forsk,Stoechospermum marginatum(Ag.)Kutz(S.marginatum),Sargassum wightii Grev,Gracilaria verrucosa(Huds.)Papenfuss and Gracilaria edulis(S.G.Gemelin)P.C.Silva against Enterococcus faecalis(MTCC 439)(E.faecalis)and one clinical isolate of vancomycin resistant E.faecalis.Methods:The selected marine macro algae were extracted with different solvents viz.,hexane,chloroform,ethyl acetate,acetone and methanol.Antibacterial assay was carried out by using disc diffusion method,determination of minimum inhibitory concentration and minimum bactericidal concentration.Results:The maximum antibacterial activity was recorded in the ethyl acetate extracts of S.marginatum and C.racemosa than the other extracts.The mean zone of inhibition produced by the extracts in agar diffusion assays against the tested bacterial strains ranged from 7.1 to 14.5 mm.The minimum inhibitory concentration was between 250 and 500μg/mL,while the minimum bactericidal concentration was from 500 to 1000μg/mL.The ethyl acetate extracts of the seaweeds showed the presence of strong terpenoids,tannins and phenolic compounds compared with the other solvent extracts.Conclusions:These findings suggest that ethyl acetate extracts of S.marginatum and C.racemosa can be used as an antibacterial substance for the treatment of infection caused by E.faecalis.

Isolation and species identification of enterococci from clinical specimen with their antimicrobial susceptibility pattern in a tertiary care hospital,Bangladesh

Objective:To investigate the species prevalence of Enterococcus with their antimicrobial resistance pattern from patients of Dhaka Medical College Hospital.Methods:Samples were cultured and Enterococcus species were identified by conventional biochemical tests as well as PCR by using species specific primers for Enterococcus faecalis(E.faecalis)and Enterococcus faecium(E.faecium).For isolation of vancomycin resistant enterococci,minimum inhibitory concentration of vancomycin and PCR was done to detect vanA and vanB genes.Results:A total of 16 enterococci were isolated from 300 urine and 200 wound swab samples(15 from urine and 1 from wound swab)from July 2011 to June 2012.Enterococci were the third most common organism(8.47%)from urine after Escherichia coli(63.28%)and Enterobacter(11.87%).Out of 16 enterococci,10(62.5%)were E.faecalis,4(25%)were E.faecium and 2(12.5%)were other species.All the enterococci(100%)were sensitive to vancomycin and linezolid.Most of the strains were resistant to ciprofloxacin and azithromycin(87.5%),gentamycin(81.25%),ceftriaxone(75%),amoxiclav(31.25%)and imipenem(25%).E.faecium was more resistant than E.faecalis to azithromycin(100%),ciprofloxacin(100%),amoxiclav(75%)and imipenem(50%).No vancomycin resistant enterococci were identified and the range of minimum inhibitory concentration for vancomycin was 1-4μg/mL.None of the enterococci were positive for vanA and vanB genes.Conclusions:The presence of multidrug resistant enterococci should be considered as danger alarm for serious enterococcal infections and further study in large scale is needed.