Ex vivo and in vivo evaluation of residual chlorhexidine gluconate on skin following repetitive exposure to saline and wiping with 2% chlorhexidine gluconate/70% isopropyl alcohol pre-operative skin preparations.

BACKGROUND: Skin antisepsis is performed before surgery to minimize the risk of surgical site infections. Chlorhexidine gluconate (CHG) is routinely used in this application, but it may be removed during surgery when prepped areas are exposed to fluid and repeated blotting. AIM: This work evaluated the effect of adding a film-forming acrylate copolymer to a CHG-containing skin preparation on minimizing CHG loss during a simulated surgical irrigation and wiping procedure. The results were compared with those obtained with a commercially available water-soluble CHG preparation. METHODS: Two studies using excised porcine skin and one study on human volunteers were performed. In each study, the CHG preparations were applied and the treated sites were challenged with repetitive saline soaks and gauze dabbing to simulate surgical conditions. Challenged and unchallenged sites were analysed either for CHG content by high-performance liquid chromatography, or for bacterial log recovery after seeding an indicator organism (reflecting remaining CHG activity). FINDINGS: After irrigation and wiping, skin treated with the film-forming CHG preparation had more CHG remaining both on excised pig skin and in the human model. In the pig model, there was a lower recovery of inoculated bacteria with the CHG preparation containing the film-forming copolymer. No skin irritation or adverse events were reported in the human study. CONCLUSIONS: The addition of a film-forming copolymer has the potential to improve the retention of CHG on skin throughout a surgical procedure compared to a water-soluble preparation. This improved retention may lead to better antimicrobial activity.

Reduced frequency of blood group Lewis a-b- in female Type 1 diabetes patients.

AIMS: To examine a disputed association between the Lewis(a(-)b(-)) phenotype and Type 1 diabetes (T1D). METHODS: Lewis red blood cell phenotyping was performed for 97 T1D White patients and 100 control subjects using monoclonal antibodies. Two historical cohorts were also included as a control population. RESULTS: T1D patients had a lower frequency (4.1%) of Lewis(a(-)b(-)) blood group compared with simultaneously tested healthy control subjects (10.0%) and the historical control group (11.1%, P = 0.02). Male T1D patients showed a Lewis(a(-)b(-)) frequency of 8.0%, which was similar to both matched healthy male donors (9.8%) and historical (9.5%) male control subjects. Unexpectedly, none of the female T1D patients displayed Lewis(a(-)b(-)) phenotype, vs. 10.3% and 10.8% of female control subjects (P = 0.039 and 0.017). CONCLUSIONS: The Lewis(a(-)b(-)) phenotype occurs less frequently in T1D compared with healthy control subjects with a strong female gender bias.