Evaluation of a new selective medium, BD BBL CHROMagar MRSA II, for detection of methicillin-resistant Staphylococcus aureus in different specimens.

The sensitivity of screening for methicillin-resistant Staphylococcus aureus (MRSA) can be improved by adding other specimen sites to nares. We describe an evaluation of a new selective medium, BBL CHROMagar MRSA II (CMRSAII), for its ability to detect MRSA from different specimen types. CMRSAII is a chromogenic medium which incorporates cefoxitin for the detection of MRSA. A study was performed at four clinical laboratories with the following specimens: 1,446 respiratory, 694 stool, 1,275 skin, and 948 wound specimens and 688 blood culture bottles containing Gram-positive cocci. The recovery of MRSA on traditional culture media was compared to results with CMRSAII. S. aureus was tested by cefoxitin disk diffusion. CMRSAII was interpreted as positive for MRSA at 24 h (range, 18 to 28 h) based solely on the visualization of mauve-colored colonies and at 48 h (range, 36 to 52 h) based on detection of mauve colonies with subsequent confirmation as S. aureus (by coagulase or latex agglutination testing). MRSA was recovered more frequently on CMRSAII (89.8% at 24 h and 95.6% at 48 h) than on traditional culture plates (83.1% at 24 h and 79.8% at 48 h) for all specimen types combined (P < 0.001). The percent sensitivities of CMRSAII at 24- and 48-h reads, respectively, were 85.5 and 92.4% for respiratory specimens, 87.9% and 98.3% for stool specimens, 88.4% and 96.1% for skin specimens, 92.1% and 94.6% for wound specimens, and 100% and 100% for positive blood cultures. The specificity was 99.8% for respiratory specimens and 100% for all others. In conclusion, CMRSAII is a reliable screening medium for multiple specimen types.

Comparison of community-associated methicillin-resistant Staphylococcus aureus from teaching hospitals in London and the USA, 2004-2006: where is USA300 in the UK?

Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) is increasingly common in the USA, but rare in the UK. We compared CA-MRSA from the UK and USA to examine differences in the molecular epidemiology. We investigated patients presenting with MRSA in the first 72 h of hospital admission or in out-patient settings in a UK and a US hospital from January 2004 to March 2006. Fluoroquinolone susceptibility was used as a screening marker to select presumptive CA-MRSA. One hundred and eighteen and 49 such strains were identified, representing a prevalence of 0.1 and 0.2 isolates per 1,000 patient days in the UK and US respectively. Panton-Valentine leukocidin (PVL)-positive ST8-IVa (USA300)-type strains predominated among 43 surviving US isolates, whereas PVL-negative ST1-IVa predominated among 71 surviving UK isolates. There are striking differences between the molecular epidemiology of CA-MRSA in UK and US hospitals, which may have implications for control.

Assessment of subjective scales for selection of patients for nasal septal surgery.

OBJECTIVE: To investigate the use of subjective measures to assist the surgeon in patient selection for septal surgery. STUDY DESIGN: Prospective, observational. Approved by local ethics committee. SETTING: ENT outpatient department, University Hospital of Wales. PARTICIPANTS: Forty-six participants on the waiting list for septal surgery for nasal obstruction. MAIN OUTCOME MEASURE: Measurement of nasal partitioning of airflow by rhinospirometer (GM Instruments, Scotland), subjective scales, and investigator's assessment of septal deviation. RESULTS: The subjective scores, and investigator's assessment of septal deviation, were compared with the rhinospirometer objective measurements for correlation, sensitivity and specificity. The rhinospirometry results showed that 20% of the patients on the waiting list had objective measures of partitioning of nasal airflow within a normal range for healthy subjects. The ordinal scale proved to be more useful than the visual analogue scale for patient selection. The subjective scores of airflow partitioning from the double ordinal scale correlated well with the rhinospirometry measurements (r = 0.8). The ordinal scale also had a sensitivity of 81% and a specificity of 60%. The investigator's subjective assessment of septal deviation had a high sensitivity at around 100% but had a lower specificity (30%). CONCLUSIONS: The use of a subjective ordinal scale to measure partitioning of airflow greatly increased the specificity of patient selection and it is proposed that this scale may be useful to the surgeon when assessing patients for septal surgery.

Effects of ageing on smell and taste.

Disorders of taste and smell commonly present diagnostic dilemmas to the medical profession. This may be secondary to the lack of knowledge and understanding of these conditions. There seems to be a low level of interest in the disorders, when compared with disruption of the other senses such as sight and hearing. Nevertheless, impairment of these senses are common and may be life threatening, especially when they involve the elderly patient. The aetiology of the conditions is widespread, and extend beyond the content of this article. This article will relate only to how the ageing process may contribute to sensory dysfunction. It will focus on how the ageing process changes the normal anatomy and physiology of the senses, how this effects the person's quality of life, and the current management of these conditions.

Long-term, but not short-term, treatment with somatotropin during pregnancy in underfed pigs increases the body size of progeny at birth.

Treatment of pigs with porcine ST (pST) in early to mid-pregnancy increases body weight and length of their fetuses by mid-pregnancy, but this increased weight may not persist to birth. We investigated the effects of short- (25 d) and long-term (75 d) treatment with pST, and interactions between long-term pST treatment and crude protein content of diet, in restricted-fed gilts. In both experiments, Large White x Landrace gilts were bred at first estrus to Large White x Duroc boars and allowed to farrow naturally. In the first experiment, gilts were fed 1.8 kg/d of a diet containing 13.5 MJ DE/kg of DM and 15.05% CP (as-fed basis) throughout pregnancy, and were injected daily with 0, 2, or 4 mg pST from d 25 to 50 of pregnancy. Maternal treatment with pST from d 25 to 50 of pregnancy did not affect the number of piglets born per litter or progeny size at birth. In the second experiment, gilts were injected daily with 0 or 2 mg of pST and fed 2.2 kg/d of a diet containing 14.5 MJ DE/kg and either (as-fed basis) 16.6% (0.81% lysine) or 22.2% CP (1.16% lysine) from d 25 to 100 of pregnancy. All gilts were then fed 3.0 kg/d of the lower protein diet from d 100 of pregnancy to farrowing. Treatment with 2 mg pST/d from d 25 to 100 of pregnancy increased live weight of all gilts during the treatment period (P = 0.016), but the change in maternal live weight from d 25 to 100 of pregnancy was only increased (P = 0.001) by pST in gilts fed the higher protein diet. Live weight of gilts 1 d after farrowing was increased by pST treatment (P = 0.007), but was not altered by protein content of diet during pregnancy. In gilts fed the lower protein diet, but not in those fed the higher protein diet, pST treatment decreased maternal backfat depth during treatment (P < 0.020) and 1 d after farrowing (P = 0.002). Treatment with pST during pregnancy did not affect the number of piglets born per litter but independently increased body weight by 11.6% (P < 0.001) and length by 3.4% (P = 0.005) of progeny at birth and decreased (P < 0.01) the negative effect of litter size on body weight at birth. We conclude that in feed-restricted gilts, fetal weight gains in response to 25 d of pST treatment before mid-pregnancy are not maintained to term but that treatment with pST during most of pregnancy increases progeny size at birth and reduces maternal constraint of fetal growth.

Consequences of inaction: importance of infection control practices.

The increasing prevalence of antimicrobial-resistant pathogens in health care facilities is due in large part to overuse of antibiotics and poor compliance with recommended infection control practices. To control the spread of such pathogens, health care facilities must reduce overuse and abuse of antibiotics, and they must implement new multidisciplinary programs to improve hand hygiene practices among health care workers and improve compliance with recommended barrier precautions.

Antiseptic technology: access, affordability, and acceptance.

Factors other than antimicrobial activity of soaps and antiseptic agents used for hand hygiene by health personnel play a role in compliance with recommendations. Hand hygiene products differ considerably in acceptance by hospital personnel. If switching from a nonmedicated soap to an antiseptic agent or increased use of an existing antiseptic agent for hand hygiene prevented a few more infections per year, additional expenditures for antiseptic agents would be offset by cost savings.

MRSA patients: proven methods to treat colonization and infection.

Methicillin-resistant Staphylococcus aureus (MRSA) infections continue to cause serious nosocomial infections in many hospitals. Measures used to control the spread of these infections include ongoing laboratory-based surveillance, placing colonized and infected patients in isolation, use of barrier precautions and handwashing and hand antisepsis. Culturing hospitalized patients at high risk of acquiring MRSA can facilitate detection and isolation of colonized patients. Eradicating MRSA nasal colonization among affected patients and healthcare personnel has also been as a control measure, with variable success. Eradicating MRSA nasal carriage from epidemiologically-implicated healthcare workers has been used on a number of occasions to control outbreaks. Attempts to eradicate MRSA colonization among affected patients has proven difficult. Of more than 40 different decolonization regimens that have been tested during the last 60 years, topical intranasal application of mupirocin ointment has proven to be the most effective. However, intranasal application of mupirocin has limited effectiveness in eradicating colonization in patients who carry the organism at multiple body sites. Furthermore, because decolonization of patients has virtually always been used in combination with other control measures, its efficacy has been difficult to determine. Because MRSA is transmitted primarily on the hands of healthcare workers, greater emphasis should be given to improving hand hygiene practices among health personnel. For patients infected with MRSA, vancomycin remains a drug of choice.

Comparative In vitro activities of daptomycin and vancomycin against resistant gram-positive pathogens.

The in vitro activity of daptomycin against 224 current gram-positive clinical isolates including vancomycin-resistant Enterococcus faecium (VREF), methicillin-resistant Staphylococcus aureus (MRSA), methicillin-resistant Staphylococcus spp. (MRSS), and penicillin-resistant Streptococcus pneumoniae (PRSP) was evaluated. The MICs at which 90% of isolates are inhibited for daptomycin and vancomycin, respectively, were as follows: MRSA, 1 and 2 microg/ml; MRSS, 1 and 4 microg/ml; PRSP, 1 and 0.5 microg/ml; and VREF, 2 and >64 microg/ml. Daptomycin was bactericidal against 82% of 17 VREF isolates. The antibacterial activity of daptomycin was strongly dependent on the calcium concentration of the medium. Daptomycin was active against all gram-positive cocci tested.

Enhancement of ethanol reward by dopamine D3 receptor blockade.

This experiment examined the influence of U-99194A, a dopamine D3 receptor antagonist, on ethanol's rewarding effect in a place conditioning paradigm. Swiss-Webster mice received six pairings of a tactile stimulus with ethanol (2 g/kg, i.p.), U-99194A (20 mg/kg, i. p.) with ethanol, or U-99194A alone. A different stimulus was paired with saline. During conditioning, ethanol or ethanol/U-99194A produced similar increases in locomotor activity. U-99194A alone produced modest increases in activity on some trials. As expected, the 2 g/kg ethanol dose produced a nonsignificant trend towards conditioned place preference. However, U-99194A enhanced the acquisition of ethanol preference, whereas U-99194A alone did not produce either place preference or aversion. The results are consistent with the notion that dopamine D3 systems are important in the response to ethanol and further suggest that D3 receptor blockade increases ethanol reward.

Skin irritation and dryness associated with two hand-hygiene regimens: soap-and-water hand washing versus hand antisepsis with an alcoholic hand gel.

OBJECTIVE: To compare the frequency of skin irritation and dryness associated with using an alcoholic-hand-gel regimen for hand antisepsis versus using soap and water for hand washing. DESIGN: Prospective randomized trial with crossover design. Irritation and dryness of nurses' hands were evaluated by self-assessment and by visual assessment by a study nurse. Epidermal water content of the dorsal surface of nurses' hands was estimated by measuring electrical capacitance of the skin. SETTING: Miriam Hospital, a 200-bed university-affiliated teaching hospital. PARTICIPANTS: Thirty-two nurses working on three hospital wards participated in the trial, which lasted 6 weeks. RESULTS: Self-assessment scores of skin irritation and dryness decreased slightly during the 2 weeks when nurses used the alcoholic-hand-gel regimen (mean baseline score, 2.72; mean final score, 2.0; P=.08) but increased substantially during the 2 weeks when nurses used soap and water (mean baseline score, 2.0; mean final score, 4.8; P<.0001). Visual assessment scores by the study nurse of skin irritation and dryness did not change significantly when the alcoholic-hand-gel regimen was used (mean baseline and final scores were both 0.55), but scores increased substantially when nurses used soap and water (baseline score, 0.59; mean final score, 1.21; P=.05). Epidermal water content of the dorsal surface of nurses' hands changed little when the alcoholic-hand-gel regimen was used (mean+/-standard deviation baseline electrical capacitance reading, 24.8+/-6.8; mean final reading, 25.7+/-7.3), but decreased significantly (skin became dryer) with soap-and-water hand washing (mean baseline, 25.9+/-7.5; mean final reading, 20.5+/-5.4; P=.0003). CONCLUSIONS: Hand antisepsis with an alcoholic-hand-gel regimen was well tolerated and did not result in skin irritation and dryness of nurses' hands. In contrast, skin irritation and dryness increased significantly when nurses washed their hands with the unmedicated soap product available in the hospital. Newer alcoholic hand gels that are tolerated better than soap may be more acceptable to staff and may lead to improved hand-hygiene practices.

Treatment of underfed pigs with GH throughout the second quarter of pregnancy increases fetal growth.

Circulating growth hormone (GH) concentrations increase in pregnancy and administration of GH during early-mid pregnancy increases fetal growth in well-fed pigs. To determine whether increased maternal GH could promote fetal growth when feed availability is restricted, fifteen cross-bred primiparous sows (gilts) were fed at approximately 30% of ad libitum intake, from mating onwards and were injected daily i.m. with recombinant porcine GH (pGH) at doses of 0, 13.4+/-0.3 and 25.6+/-0.5 microg/kg live weight from day 25 to day 51 of pregnancy (term approximately 115 days). Treatment with pGH increased maternal backfat loss between day 25 and day 51 of pregnancy, and increased maternal plasma IGF-I concentrations measured at day 51 of pregnancy. Fetal body weight, length and skull width at day 51 of pregnancy were increased by maternal treatment with pGH. Fetal plasma glucose concentrations were increased and maternal/fetal plasma glucose concentration gradients were decreased by maternal pGH treatment at 13.4, but not 25.6 microg/kg.day. Fetal plasma concentrations of urea were decreased by both levels of pGH treatment. Overall, fetal weight was negatively correlated with fetal plasma concentrations of urea, positively correlated with maternal plasma alpha-amino nitrogen concentrations and unrelated to glucose concentrations in either maternal or fetal plasma. This suggests that the availability of amino acids, not glucose, limits fetal growth in the first half of pregnancy in underfed gilts, and that maternal GH treatment may improve amino acid delivery to the fetus.

Misclassification of susceptible strains of Staphylococcus aureus as methicillin-resistant S. aureus By a rapid automated susceptibility testing system.

Eight Staphylococcus aureus strains initially identified by Vitek GPS-BS or GPS-SA cards as resistant to oxacillin, but susceptible to most non-beta-lactam antibiotics, were found on further testing to be susceptible to oxacillin and ceftizoxime by disk diffusion tests. For all these strains, the MICs of oxacillin were

Environmental contamination due to methicillin-resistant Staphylococcus aureus: possible infection control implications.

OBJECTIVE: To study the possible role of contaminated environmental surfaces as a reservoir of methicillin-resistant Staphylococcus aureus (MRSA) in hospitals. DESIGN: A prospective culture survey of inanimate objects in the rooms of patients with MRSA. SETTING: A 200-bed university-affiliated teaching hospital. PATIENTS: Thirty-eight consecutive patients colonized or infected with MRSA. Patients represented endemic MRSA cases. RESULTS: Ninety-six (27%) of 350 surfaces sampled in the rooms of affected patients were contaminated with MRSA. When patients had MRSA in a wound or urine, 36% of surfaces were contaminated. In contrast, when MRSA was isolated from other body sites, only 6% of surfaces were contaminated (odds ratio, 8.8; 95% confidence interval, 3.7-25.5; P < .0001). Environmental contamination occurred in the rooms of 73% of infected patients and 69% of colonized patients. Frequently contaminated objects included the floor, bed linens, the patient's gown, overbed tables, and blood pressure cuffs. Sixty-five percent of nurses who had performed morning patient-care activities on patients with MRSA in a wound or urine contaminated their nursing uniforms or gowns with MRSA. Forty-two percent of personnel who had no direct contact with such patients, but had touched contaminated surfaces, contaminated their gloves with MRSA. CONCLUSIONS: We concluded that inanimate surfaces near affected patients commonly become contaminated with MRSA and that the frequency of contamination is affected by the body site at which patients are colonized or infected. That personnel may contaminate their gloves (or possibly their hands) by touching such surfaces suggests that contaminated environmental surfaces may serve as a reservoir of MRSA in hospitals.