Comparison of the microbicidal efficacy on germ carriers of several tertiary amine compounds with ortho-phthalaldehyde and Perasafe.

Several tertiary amine formulations have been marketed as high-level disinfectants (HLDs). This study compared some of these formulations with two accepted HLDs [ortho-phthalaldehyde (OPA) and Perasafe] by determining the bactericidal effect on 52 micro-organisms using a metallic germ carrier, determining the sporicidal effect using a commercial germ carrier (3M spores), and performing a corrosion test on surgical blades with human blood. OPA and Perasafe were significantly more effective than all the tertiary amines tested, and acted within a contact time of 10 min compared with 20 min for the other products. For Gram-negative micro-organisms, Instrunet FA showed no significant differences at 20 min compared with OPA and Perasafe at 10 min. The amines tested did not differ significantly in global bactericidal efficacy. Unlike the tertiary amines, OPA and Perasafe were effective against mycobacteria (15-min contact period), but were not sporicidal. All agents (except one tertiary amine) passed the corrosion test. In conclusion, OPA and Perasafe can be considered as HLDs. However, 15-20 min of contact is required and both products have disadvantages.

The influence of laboratory adaptation on test strains, such as Pseudomonas aeruginosa, in the evaluation of the antimicrobial efficacy of ortho-phthalaldehyde.

The microbiocidal efficacy of 0.55% ortho-pthalaldehyde (OPA) was evaluated in a rough carrier test, using more than 200 strains of bacteria and yeasts from patients and reference ATCC strains. This test was then compared with the European carrier test (prEN14561) using Pseudomonas aeruginosa. We also sought to determine whether recently isolated P. aeruginosa had the same susceptibility to OPA, after laboratory adaptation. It was shown that P. aeruginosa was less susceptible to OPA (being reduced by a factor of 10(3.8)) than the other strains (reduced by a factor of 10(4)). The surface test used, produced a lesser reduction of P. aeruginosa than the European test. For recently isolated strains (N = 66), the rough model demonstrated that the number of survivors increased both quantitatively and qualitatively from day one to day seven. It was concluded that disinfectant efficacy should be confirmed with recently isolated organisms.

Comparison of the disinfectant efficacy of Perasafe and 2% glutaraldehyde in in vitro tests.

Two percent glutaraldehyde has been the reference disinfectant for high-level disinfection, but its frequent association with adverse effects has stimulated a search for newer disinfectants. We compared the efficacy of 2% glutaraldehyde with that of a new disinfectant formulation, Perasafe (0.2% peracetic acid) in six in vitro tests: germicidal effect in a suspension of micro-organisms; using a microbe-contaminated metallic endodoncy file; an endoscope model; a modified capacity test; a sporicidal test, and corrosiveness on metallic instruments. Both products were effective germicides in 10-20 min, completely destroying microbial inocula except for Mycobacterium and spores. Internal irrigation of endoscopes with 100 mL of either was totally effective. Both substances resisted inactivation after repeated inoculation and did not corrode clean instruments; however, when organic matter was added the 0.2% peracetic acid formulation cleaned without corrosion, while 2% glutaraldehyde fixed the matter to the scalpel, causing corrosion within 2 h. In summary, Perasafe is a good substitute for 2% glutaraldehyde for high-level disinfection.

Usefulness of an alcohol solution of N-duopropenide for the surgical antisepsis of the hands compared with handwashing with iodine-povidone and chlorhexidine: clinical essay.

BACKGROUND: The usual surgical antisepsis involves scrubbing the skin with antiseptic solutions. This procedure can damage the skin, with the subsequent risk of infection for the patient. There are several efficient and quick-acting antiseptic alcohol solutions that require no scrubbing. MATERIAL AND METHODS: We compare four alcohol solutions with the classic surgical handwashing products (chlorhexidine and iodine-povidone), in both in vitro (pigskin germ carriers) and in vivo studies. The latter (clinical essays) were done with healthy volunteers (crossed design) as well as with 154 surgical team members (Plastic Surgery or Traumatology), whose hand microbial flora were measured before and after scrubbing up and after surgery. RESULTS AND DISCUSSION: Because of its efficiency in the germ carrier, we chose a solution of N-duopropenide in 60 degrees alcohol with emollients for further comparison with the standard surgical scrub: 4% chlorhexidine and 7.5% iodine-povidone. The quantitative, semiquantitative, and qualitative results obtained with N-duopropenide without scrubbing were better in the healthy volunteers and surgical teams. This product reduced hand microorganisms by more than 2 log, and maintained the reduction for the entire study period. Four percent chlorhexidine initially reduced colonization more than 2 log but lost part of its effect over time during the surgical intervention. Last, 7.5% iodine-povidone reduced the germs by 1 log but at the end of surgery there were even more germs than before washing. CONCLUSION: Because of its efficacy, persistent effect, and skin protection, we advise that scrubbing with classic antiseptic solutions be replaced with gentle washing with an alcohol solution such as N-duopropenide in alcohol.

Analytic epidemiology of clinical urinary tract infection in spinal cord injury.

The authors studied all patients (121) who were admitted to the National Paraplegic Center of Toledo, during a 6-month period, with spinal cord injuries (SCI). We obtained a clinical urinary tract infection predictive equation dependent on different risk factors (age, hospitalization time, level of SCI, sex, etc.). It is important to note that the main clinical-UTI risk factors were: (1) age, (2) hospitalization period, and (3) SCI category. We also achieved a mathematical model that we can use when the patient is admitted to this Center (in this case we do not include hospitalization time). This model enables us to predict clinical UTI depending on patient characteristics.

Efficacy of a broad-spectrum antibiotic (mupirocin) in an in vitro model of infected skin.

The microbicidal effect of mupirocin (Bactroban) was studied using an in vitro model of burn eschar in contact with this antimicrobial cream, to indicate its inhibiting action after 1, 2, 4, and 24 h. The microorganisms used were 20 isolates of Ps. aeruginosa, 20 isolates of MRSA, 10 isolates of Staph. epidermidis, 12 isolates of Enterobacteriaceae and eight isolates of Candida albicans. There was a marked effect on Gram-negative bacilli (< 0.1 per cent surviving) by 4 h, whereas on Gram-positive organisms its effect was slower, principally on MRSA with 2.2 per cent survivors by 24 h. The action on Candida was very slow initially, but after 24 h, the mupirocin's effect was marked (< 0.1 per cent survivors). The studies showed that mupirocin (a topical broad-spectrum antimicrobial agent) can be used in vitro against Gram-positive and Gram-negative bacteria and yeasts, which contaminate skin and mucosa. Further clinical experience is required before mupirocin can be used to treat colonized or infected wounds in burned patients.

Predictive equation for acquisition of hepatitis B in hospital workers in a general hospital.

A cross-sectional study was performed to obtain risk factors for hepatitis B disease, HBsAg carriers and immunised personnel, among 2470 workers in a general hospital in Madrid, Spain. The data obtained were analyzed with multiple logistic regression to obtain beta coefficients for variables. The results of the analysis show that being a nurse or being regularly exposed to blood are the most important risk factors for hepatitis B acquisition. The length of time working at the same job activity was also a risk factor. The resulting beta coefficients allow the construction for a hepatitis non-immunised, HBsAg carrier and immunised HBV status, which can select subjects for a hepatitis B vaccination program.

[Hepatitis B vaccination in children and adolescents]. / Vacunación contra la hepatitis B en niños y adolescentes.

OBJECTIVE: This study's main aim was to investigate the immunogenicity of genetic recombinant vaccine in children and adolescents in Madrid, with the intention of determining the length of protection according to the titer of antibodies. A second aim was that of finding the optimum vaccine dosage, in order to suggest possible courses of action leading to an adequate strategy of vaccination. DESIGN: Crossover study. SETTING: Three educational centres in Madrid. PATIENTS AND OTHERS PARTICIPANTS: 1,184 pupils between 5 and 17 years old. INTERVENTIONS: Each individual was given three doses of Engerix B recombinant vaccine in the deltoid area at 0, 1 and 6 months. The vaccine dosage was 10 micrograms for children under 12 and 20 micrograms for those aged 12 and over. MAIN MEASUREMENTS AND RESULTS: The pre-vaccination markers were determined. A month after completing the vaccination, the titer of antibodies was quantified using the Abbott laboratories' microenzyme-immunoanalysis technique. The overall seroprotection rate was 98.9%. The MGT of the titer of antibodies was 9,283.2 mUI/ml. The seroprotection rates were similar among children under 12. The rates were also similar among those who were 12 or over, with titers of antibodies showing significantly higher in the children aged 12 or over. CONCLUSIONS: Given the good results obtained, we consider that the children will be protected for about 10 years. We suggest that all children and/or adolescents should be vaccinated as a means of controlling Hepatitis B. The recommended dosage for children under 8 is 10 micrograms and for those aged 8 and over, 20 micrograms.

[The descriptive and analytical epidemiology of traumatic spinal cord lesions occurring in Spain during 1984 and 1985]. / Epidemiología descriptiva y analítica de la lesión medular espinal traumática ocurrida en España durante 1984 y 1985.

Descriptive and analytic epidemiology of traumatic spinal cord injury (Traumatic-SCI) in Spain, with a sample of 33% of all incidental cases between 1984 and 1985, underlining the traffic accidents as the origin of those lesions. OR was obtained next of different variables of T-SCI, after controlling possible confusing factors through logistic regression and taking as "control group" Non Traumatic-SCI. OR in Traumatic-SCI decreases with age and in females. These Traumatic-SCI produce especially "cervical" lesions (OR = 3) and "complete" (OR = 4) with higher dependence on second persons. In the rest of variables there are no significative differences.

Diagnosis of local infection of a burn by semiquantitative culture of the eschar surface.

The purpose of this study was to determine whether semiquantitative surface cultures of the burn eschar are as reliable or useful as the classic invasive biopsy culture method. We used eschars from patients with burns in an in vitro system. Lyophilized pigskin was used to validate our methodology. Because of its simplicity and high degree of sensitivity and specificity as compared with quantitative biopsy culture, semiquantitative surface culture has a place in burn wound surveillance.

A new in vitro model to test the effectiveness of topical antimicrobial agents. Use of an artificial eschar.

An in vitro method using a burn eschar 'equivalent' is described to compare the efficacy of several antimicrobial creams. Fragments of lyophilized pigskin were used as 'germ carriers' and after 24 h of treatment the effectiveness of the antimicrobial creams was tested through the evaluation of bacterial recovery both from the surface and from within the 'germ carriers'. The results showed a striking full skin thickness effectiveness of 0.5 per cent chlorhexidine, 10 per cent providone iodine and 2 per cent cerium nitrate in comparison with the weak activity demonstrated by 1 per cent silver sulphadiazine cream.

Evaluation of the penetration strength, bactericidal efficacy and spectrum of action of several antimicrobial creams against isolated microorganisms in a burn centre.

The antibacterial activity of eight antiseptic creams: 1 per cent silver sulphadiazine; 0.2 per cent nitrofurazone; 0.1, 0.5 and 1 per cent chlorhexidine; 2.2 per cent cerium nitrate; 10 per cent povidone iodine; and 1 per cent silver sulphadiazine with 2.2 per cent cerium nitrate were evaluated in vitro. The evaluation included the minimum inhibitory concentration (MIC) against 100 microorganisms isolated from burn patients, the chronology of the bacterial activity against Ps. aeruginosa and Staph. aureus and the penetration strength of the creams through a novel in vitro model contaminated with 17 microorganisms of different species isolated from burn patients. The results revealed that 0.5 per cent or 1 per cent chlorhexidine, 2.2 per cent cerium nitrate, and 1 per cent silver sulphadiazine with 2.2 per cent cerium nitrate were the creams which were effective at the highest dilutions. 0.5 per cent chlorhexidine and 10 per cent povidone iodine had the greater bactericidal activity. Finally, 0.2 per cent nitrofurazone showed greater penetration strength within the eschar model in comparison with the weaker penetration of 0.5 per cent and 1 per cent chlorhexidine and the absence of penetration by the rest of the antibacterial creams.