An interesting increase in immediate and residual efficacy of a trade mark of alcoholic 2% chlorhexidine gluconate, with and without dye, has been demonstrated by an in vitro study with ATCC micro-organisms and strains isolated from ICU patients.

AIM: ChloraPrep™ (CHP) is a clear solution of 2% (w/v) chlorhexidine (CHG) in 70% (v/v) isopropyl alcohol (IPA) administered with a specially designed sterile single-use applicator in which a tinting agent can be added to the CHP solution upon activation of applicator immediately prior to patient skin preparation (CHP+T). This study investigated whether the immediate and residual efficacy of CHP vs CHP+T and a stock solution of 2% CHG in 70% IPA varied, and whether CHP was compromised by the addition of the dye. METHODS AND RESULTS: We compared the immediate and residual activity (in 1 min) of 70% IPA with that of 2% CHG in 70% IPA stock solution prepared in the laboratory against CHP+T and CHP, against 22 micro-organisms (5 ATCC and 18 clinical isolates) on germ-carriers. CHP and CHP+T demonstrated superior immediate and residual efficacy compared to the 70% IPA plus 2% CHG in 70% IPA stock solutions. Each antiseptic tested showed greater efficacy against the Gram-positive bacteria than against the Gram-negative bacteria. However, their antimicrobial effect on yeasts was even lower. CONCLUSIONS: CHP and CHP+T have superior immediate and residual efficacy compared to stock 70% IPA and 2% CHG in 70% IPA solutions, and CHP+T is not affected by the tinting agent. SIGNIFICANCE AND IMPACT OF THE STUDY: ChloraPrep is a product which can be stained just before use. We have demonstrated that the immediate and residual efficacy of the antimicrobial solution is not compromised by the dye. The efficacy of CHP is greater against bacteria than against yeasts obtained from ICU patients. Interestingly, CHP is more effective against bacteria than a formula made in the laboratory with the same basic components (2% chlorhexidine and 70% IPA). The intermittent heat sterilization process of the commercial preparation might hypothetically have improved the residual activity of the CHP solutions.

Surgical hand preparation with chlorhexidine soap or povidone iodine: new methods to increase immediate and residual effectiveness, and provide a safe alternative to alcohol solutions.

BACKGROUND: Surgical use of 4% chlorhexidine soap (CHX-4) and 10% povidone iodine (PVP-I-10) does not meet the standards defined by EN 12791. AIM: To investigate the possibility of increasing the immediate and residual effects of these antiseptics. METHODS: Over three consecutive weeks, n-propanol, standard CHX-4 and PVP-I-10 were tested in two experimental groups of volunteers. The new method for applying the antiseptic substances involved standard hand rub and rinse of CHX-4 or PVP-I-10, followed by application of an aqueous solution based on 5% chlorhexidine or PVP-I-10 with no further rinsing of the hands prior to donning gloves. Samples were taken to assess immediate and residual effects, analysing the logarithmic reduction of colony-forming units. FINDINGS: At t=0 h, n-propanol was superior in bactericidal effect to standard CHX-4 (P<0.05), but the new chlorhexidine protocol was superior to both standard CHX-4 (P<0.01) and n-propanol (P<0.05); the same effect was observed at t=3 h (residual effect). At t=0 h, n-propanol was significantly superior to standard PVP-I-10, but the new PVP-I-10 protocol was superior, although not significantly, to n-propanol. There was no significant residual effect at t=3 h. CONCLUSION: The new protocol for chlorhexidine application permits surgical hand preparation with chlorhexidine, as a safe alternative to alcohol solutions, because it meets the standards defined by EN 12791.

Microbial competition in environmental nosocomial reservoirs and diffusion capacity of OXA48-Klebsiella pneumoniae: potential impact on patients and possible control methods.

BACKGROUND: We have found clusters of Klebsiella pneumoniae with OXA48-carbepenemase cases in some hospital rooms, and decided to investigate whether bathroom siphons could be a reservoir for OXA48 bacteria, as occurs with K. oxytoca with other types of carbepenemases. METHODS: We evaluated the microbial competition between strains with OXA48 and VIM carbepenemases, in diluted nutrient-broth, on a slime germ-carrier. We compared the number of colonies at 5 and 10 days on the contaminated carriers with one or two strains. We evaluated the dissemination of K. pneumoniae with carbepenemase OXA48 or VIM from thumbs and index fingers of volunteers, to standard surfaces (20 glass germ-carrier by each volunteer). After, we counted the number of microorganisms on each carrier. Microbiological weekly studies of faecal microbiota of all patients were obtained in Traumatology and Oncology. Moreover, we studied samples of the sink in their rooms. PCR and MLST sequence-type was determined in all K. pneumoniae diagnosed from patients and sinks. RESULTS: A large possibility of diffusion from contaminated hands, which continue to transmit high numbers of microorganisms after more than 10 successive surface contacts, was highlighted; OXA bacteria were more persistent than VIM bacteria. Microbial competition studies showed that VIM bacteria are inhibited by OXA ones. These observations can explain the concentration of cases of K. pneumoniae OXA48 in some rooms in Traumatology and Oncology, producing a significant OR between rooms with OXA48-bacteria-contaminated siphons and other rooms (3.1 and 3.3 respectively). Risk was lowered after changing or disinfecting (heat plus chlorinated disinfectant) the contaminated siphons. Siphon colonization by VIM bacteria was not related with human infections by similar microorganisms. CONCLUSIONS: Bathroom siphons can be a reservoir for K. pneumoniae OXA48 and lead to outbreaks. Outbreaks can be controlled by replacement or heat plus chemical treatment of the sink-siphons.

An exception to the rule "no association between antibiotic resistance and decreased disinfectant microbicidal efficacy": Orthophthalaldehyde (OPA) and Pseudomonas aeruginosa isolated from ICU and paraplegic patients.

BACKGROUND: Antibiotic resistance and decreased susceptibility to disinfectants are not usually associated in microorganisms, but we have found an exception to this rule: P. aeruginosa versus orthophthalaldehyde (OPA). METHODS: Bactericidal effect of OPA was measured at 10 minutes on endodoncy files contaminated with an ATCC strain (control) or 206 strains of P. aeruginosa recently isolated from 206 ICU and paraplegic patients in a tertiary university hospital, in two consecutive years. RESULTS: Differences in bactericidal effect of OPA were found between the strains isolated each year (decreased susceptibility in the first period), but in both years the statistical differences (p < 0.05) were maintained according to whether the strains were "susceptible" to antibiotics, "resistant" (to one family of antibiotics) or "multi-resistant" (resistant to more than one family of antibiotics), exhibiting a reduction in their OPA susceptibility in parallel to an increase of their antibiotic resistance. In contrast, there were no differences depending on the type of sample (sputum, urine, faeces, pharynx) or of patient (paraplegic or ICU: adult, newborn, burn). Finally we selected 15 strains with an OPA effect below 3.5 log10 at 10 minutes and repeated the study with an OPA exposure of 15 minutes. In these conditions OPA showed a total bactericidal effect on these P. aeruginosa strains. CONCLUSIONS: There was an association between antibiotic resistance and decreased OPA susceptibility. This normally does not require an increase in disinfection time, but, for endoscope disinfection or instruments from colonized/infected patients with resistant/multiresistant P. aeruginosa, we consider it better to use 15 min of OPA. Regular tests (e.g., once every 12 months) with germ-carriers, should be performed to assess ecological changes in susceptibility to high level disinfectants and must include not only ATCC strains, but also recently isolated microorganisms with different antibiotic sensitivities (susceptible, resistant and multi-resistant).

Quantifying Glosair™ 400 efficacy for surface disinfection of American Type Culture Collection strains and micro-organisms recently isolated from intensive care unit patients.

Microbial contamination of hospital surfaces may be a source of infection for hospitalized patients. We evaluated the efficacy of Glosair™ 400 against two American Type Culture Collection strains and 18 clinical isolates, placed on glass germ-carriers. Carriers were left to air-dry for 60 min and then exposed to a cycle before detection of any surviving micro-organisms. Antibiotic-susceptible Gram-negative bacilli were less susceptible (although not significantly) to this technique than resistant Gram-negative bacilli or Gram-positive cocci and yeasts (3, 3.4 and 4.6 log10 reduction, respectively). In conclusion, in areas that had not been cleaned, aerosolized hydrogen peroxide obtained >3 log10 mean destruction of patients' micro-organisms.

Effectiveness of oxaliplatin desensitization protocols

INTRODUCTION: Hypersensitivity reaction (HSR) to antineoplastic drugs can force doctors to stop treatment and seek other alternatives. These alternatives may be less effective, not as well tolerated and/or more expensive. Another option is to use desensitization protocols that induce a temporary state of tolerance by gradually administering small quantities of the antineoplastic drug until the therapeutic dosage is reached. The aim of this study is to assess the effectiveness of oxaliplatin desensitization protocols. MATERIALS AND METHODS: A retrospective observational study was carried out between January 2006 and May 2011. The inclusion criteria were patients undergoing chemotherapy treatment with oxaliplatin who had developed an HSR to the drug and who were candidates for continuing the treatment using a desensitization protocol. The patients' clinical records were reviewed and variables were gathered relating to the patient, the treatment, the HSR, and the desensitization protocol administered. The data were analysed using version 18.0 of the statistics program SPSS. RESULTS: A total of 53 desensitization protocols were administered to 21 patients. In 89 % of these cases, no new reactions occurred while the drug was being administered. New reactions of mild severity only occurred in 11 % of cases, and none of these reactions were severe enough for treatment to be stopped. All patients were able to complete the desensitization protocol. CONCLUSION: This study confirms that oxaliplatin desensitization protocols are safe and effective and allow patients to continue with the treatment that initially caused an HSR (AU)

In vitro-in vivo sequence studies as a method of selecting the most efficacious alcohol-based solution for hygienic hand disinfection.

The use of alcohol-based hand rubs serves to reduce hospital-acquired infections. Many products of this type are now on offer and it is essential to know how to rank their efficacy. A sequence of tests is proposed here to compare any given new alcohol-based solution against the reference solution (60% 2-isopropyl-alcohol) with 30 s of contact time: (i) in vitro (with pig skin as carrier) testing of >30 species of microorganism; (ii) in vitro assessment of residual efficacy (after 30 min of drying); (iii) in vivo study of transient microbiota (modification of the EN 1500 standard procedure) using four ATCC strains; (iv) in vivo study of resident hand microbiota. After performing the in vitro evaluation of seven alcohol-based hand rubs, the two most efficacious (chlorhexidine-quac-alcohol and mecetronium- alcohol) were chosen and studied, comparatively with the reference solution (60% isopropyl alcohol), in vitro (for chemical sustainability on the skin) and in vivo (against transient and resident microbiota). Chlorhexidine-quac-alcohol proved to be significantly superior to mecetronium-alcohol or the reference solution in all tests, except against resident microbiota for which the improvement was not statistically significant.

[Identification of yeast and sensitivity in vitro against different antifungal agents]. / Identificación de levaduras y sensibilidad in vitro a diversos antifúngicos.

INTRODUCTION: The increasing incidence of Candida yeasts infections and its hospital and community repercussion (vaginal thrush), as well as the will to acquire the knowledge of the new antifungal that were launched to the therapeutic store, have motivated us to identify that type of yeasts from different sources, as well as to study their behaviour against the antifungal, using commercial procedures with easy clinical application. MATERIALS AND METHODS: An amount of 317 Candida yeasts were identified through commercial procedures (CHROMagar Candida and Auxacolor): 108 vaginals, 138 from ICU newborn children and 71 from ICU adults, while the antifungal drug susceptibilities was done to 199 of the isolated ones using another commercial procedure (Fungitest). RESULTS AND CONCLUSIONS: Candida albicans is identified as the most frequent in both hospital and community samples (78.7 and 45.93%, respectively), followed by Candida glabrata (19.44 and 28.23%, respectively). The sensitivity to amphotericin B and to 5-flucytosine was very high in every studied group, while sensitivity to imidazole derivatives depends on the samples source (lower sensitivity in the ICU newborn isolated ones) and the species (C. glabrata is less sensitive than C. albicans).

[Immunogenicity of the vaccine against hepatitis B virus in schoolchildren of Madrid]. / Inmunogenicidad de la vacuna contra el virus de la hepatitis B en escolares de Madrid.

We carried out a vaccine program against Hepatitis B in scholar population aged 5 to 17 educated in 3 institutions of Madrid city/ region. Those children who followed the vaccination criteria (negative HBsAg and Anti HBc markers) were vaccinated. The vaccination regimen (Engerix B recombinant DNA vaccine) was 0-1-6 months and dose was 10 and 20 ug i.m. for those aged 6 to 13 and 13 to 17 respectively. The postvaccine serologic results (anti-HBs titer) was evaluated one month after tha last dose, at 7th month from the beginning. The variables of study were age and sex for each individual. Corresponding to these variables both seroconversion rate (percentage of patients with 10 Ul/l of-anti-HBs) and the geometric mean titer of antibodies (GMT anti-HBs titer) were determined. The overall seroconversion rate at 7th month was 99%. There is not significant association neither regarding the sex nor mean age between "responders" and "no responders". The titer of anti-HBs antibodies, expressed using the G.M.T., which was reached at 7th month was 9.283.2 UI/I. Finally, there is not correlation between age and anti-HBs antibody titer.

Antibodies to simian vacuolating virus 40 in bladder cancer patients.

The occurrence of antibodies to herpes simplex virus type 2 (HSV-2) and simian vacuolating virus 40 (SV40) (two presumptive oncogenic viruses) was investigated by the technique of enzyme-linked immunosorbent assay in 233 patients with bladder cancer (200 males and 33 females) and in 466 controls (400 males and 66 females). The age of both the bladder cancer patients and controls varied from 55 to 65 years. A statistically significant association between bladder cancer and antibodies to SV40 was found in both males and females. No association between HSV-2 and bladder cancer was observed.