Iodine-impregnated incision drape and bacterial recolonization in simulated total knee arthroplasty

Background and purpose - Iodine-impregnated incision drapes (IIIDs) are used to prevent surgical site infection (SSI). However, there is some evidence to suggest a potential increase in SSI risk as a result of IIID use, possibly from promotion of skin recolonization. A greater number of viable bacteria in the surgical field of an arthroplasty, and surgery in general, may increase the infection risk. We investigated whether IIID use increases bacterial recolonization compared to no drape use under conditions of simulated total knee arthroplasty (TKA). Methods - 20 patients scheduled for TKA were recruited. Each patient had 1 knee randomized for draping with IIID, while the contralateral knee was left bare. The patients thus served as their own control. The operating room conditions and perioperative procedures of a TKA were simulated. Cylinder samples were collected from the skin of each knee prior to disinfection, and again on 2 occasions after skin preparation-75 min apart. Quantities of bacteria were estimated using a spread plate technique under aerobic conditions. Results - We found similar quantities of bacteria on the intervention and control knees immediately after skin disinfection and after 75 min of simulated surgery. These quantities had not increased at the end of surgery when compared to baseline, so no recolonization was detected on the draped knees or on the bare knees. Interpretation - The use of IIIDs did not increase bacterial recolonization in simulated TKA. This study does not support the hypothesis that IIIDs promote bacterial recolonization and postoperative infection risk.

Uropathogenic Escherichia coli Express Type 1 Fimbriae Only in Surface Adherent Populations Under Physiological Growth Conditions

BACKGROUND

Most uropathogenic Escherichia coli (UPEC) strains harbor genes encoding adhesive type 1 fimbria (T1F). T1F is a key factor for successful establishment of urinary tract infection. However, UPEC strains typically do not express T1F in the bladder urine, and little is understood about its induction in vivo.

METHODS

A flow chamber infection model was used to grow UPEC under conditions simulating distinct infection niches in the bladder. Type 1 fimbriation on isolated UPEC was subsequently determined by yeast cell agglutination and immunofluorescence microscopy, and the results were correlated with the ability to adhere to and invade cultured human bladder cells.

RESULTS

Although inactive during planktonic growth in urine, T1F expression occurs when UPEC settles on and infects bladder epithelial cells or colonizes catheters. As a result, UPEC in these sessile populations enhances bladder cell adhesion and invasion potential. Only T1F-negative UPEC are subsequently released to the urine, thus limiting T1F expression to surface-associated UPEC alone.

CONCLUSIONS

Our results demonstrate that T1F expression is strictly regulated under physiological growth conditions with increased expression during surface growth adaptation and infection of uroepithelial cells. This leads to separation of UPEC into low-expression planktonic populations and high-expression sessile populations.

Low Completeness of Bacteraemia Registration in the Danish National Patient Registry

Bacteraemia is associated with significant morbidity and mortality and timely access to relia-ble information is essential for health care administrators. Therefore, we investigated the complete-ness of bacteraemia registration in the Danish National Patient Registry (DNPR) containing hospital discharge diagnoses and surgical procedures for all non-psychiatric patients. As gold standard we identified bacteraemia patients in three defined areas of Denmark (~2.3 million inhabitants) from 2000 through 2011 by use of blood culture data retrieved from electronic microbiology databases. Diagnoses coded according to the International Classification of Diseases, version 10, and surgical procedure codes were retrieved from the DNPR. The codes were categorized into seven groups, ranked a priori according to the likelihood of bacteraemia. Completeness was analysed by contin-gency tables, for all patients and subgroups. We identified 58,139 bacteraemic episodes in 48,450 patients; 37,740 episodes (64.9%) were covered by one or more discharge diagnoses within the sev-en diagnosis/surgery groups and 18,786 episodes (32.3%) had a code within the highest priority group. Completeness varied substantially according to speciality (from 17.9% for surgical to 36.4% for medical), place of acquisition (from 26.0% for nosocomial to 36.2% for community), and mi-croorganism (from 19.5% for anaerobic Gram-negative bacteria to 36.8% for haemolytic strepto-cocci). The completeness increased from 25.1% in 2000 to 35.1% in 2011. In conclusion, one third of the bacteraemic episodes did not have a relevant diagnosis in the Danish administrative registry recording all non-psychiatric contacts. This source of information should be used cautiously to iden-tify patients with bacteraemia.

Outbreak of Pseudomonas aeruginosa bacteraemia in a haematology department

INTRODUCTION

Infection by Pseudomonas aeruginosa represents a major cause of morbidity and mortality among immunocompromised patients. In Denmark, an increase in P. aeruginosa isolates from blood cultures from a haematology department prompted a hygienic audit in 2007.

METHODS

Blood cultures that tested positive for P. aeruginosa were collected from the laboratory information system (MADS, Skejby Hospital, Aarhus, Denmark). Environmental samples were obtained from shower heads in the department. The genotype was established by pulse field gel electrophoresis (PFGE). An audit was conducted during the outbreak and 12 months later. The audits were conducted by the method of direct observation.

RESULTS

Several PFGE types were involved with no clear association to isolates from environmental samples. The audit revealed poor hygiene related to the handling of central venous catheters. After optimising catheter hygiene, the number of P. aeruginosa bacteraemia cases fell significantly.

CONCLUSION

Since no clear association between patient and environmental genotype was established, it was suspected that central venous catheters were the main portal of entry. This was further supported by a simultaneous decline in bacteraemia cases with coagulase-negative staphylococci. Though several hygienic precautions were taken, the increased focus on disinfection of hubs and injection ports was presumably the more important element.

FUNDING

not relevant.

TRIAL REGISTRATION

not relevant.

Clarithromycin for stable coronary heart disease increases all-cause and cardiovascular mortality and cerebrovascular morbidity over 10years in the CLARICOR randomised, blinded clinical trial

BACKGROUND

The CLARICOR trial reported that clarithromycin compared with placebo increased all-cause mortality in patients with stable coronary heart disease. This study investigates the effects of clarithromycin versus placebo during 10years follow up.

METHODS

The CLARICOR trial is a randomised, placebo-controlled trial including 4373 patients with stable coronary heart disease. The interventions were 2weeks of clarithromycin 500mg a day versus placebo. 10year follow up was performed through Danish public registers and analysed with Cox regression.

RESULTS

Clarithromycin increased all-cause mortality (hazard ratio (HR): 1.10, 95% confidence interval (CI): 1.00-1.21) and cerebrovascular disease during 10years (HR: 1.19, 95% CI: 1.02-1.38). The increased mortality and morbidity were restricted to patients not on statin at entry (HR: 1.16, 95% CI: 1.04-1.31, and HR: 1.25, 95% CI: 1.03-1.50). The assumption of constant HR during the 10years was violated for cardiovascular death (P=0.01) and cardiovascular death outside hospital (P<0.0005). Analyses of the effects over time showed that clarithromycin increased cardiovascular mortality during the first three years (HR: 1.42, 95% CI: 1.09-1.84) due to increased cardiovascular mortality outside hospital in patients not on statin (HR: 2.36, 95% CI: 1.60-3.50). During the last 4years, cardiovascular death outside hospital was lower in the clarithromycin group (HR: 0.64, 95% CI: 0.46-0.88).

CONCLUSION

Clarithromycin increased mortality due to cardiovascular death outside hospital and cerebrovascular morbidity in patients with stable coronary heart disease who were not on statin. The increased cardiovascular mortality was years later compensated, likely through frailty attrition.

Quantification of filamentation by uropathogenic Escherichia coli during experimental bladder cell infection by using semi-automated image analysis

Several rod-shaped pathogens including Escherichia coli, Salmonella spp. and Klebsiella pneumonia are capable of adopting highly filamentous cell shapes under certain circumstances. This phenomenon occurs as a result of continued cell elongation during growth without the usual septation into single rod-shaped cells. Evidence has emerged over the past decade suggesting that this morphological transformation is controlled and reversible and provides selective advantages under certain growth conditions, such as during infection in humans. In order to identify the factors which induce filamentation of bacterial pathogens and study the advantages of bacterial morphological plasticity, methods are needed to accurately quantify changes in bacterial cell shape. In this study, we present a method for quantification of bacterial filamentation based on automatic detection and measurement of bacterial units in focus-stacked microscopy images. Used in combination with a flow-chamber based in vitro cystitis model, we study the factors involved in filament formation by uropathogenic E. coli (UPEC) during infection. The influence of substratum surface, intracellular proliferation and flow media on UPEC filamentation is evaluated. We show that reversible UPEC filamentation during cystitis is not dependent on intracellular infection, which previous studies have suggested. Instead, we find that filamentation can be induced by contact with surfaces, both biological and artificial. Lastly our data indicate that UPEC filamentation is induced by trace-amounts of specific components in urine, rather than being a generic stress-response to high urine salt concentrations. The study shows that the combined methodology is generally useful for investigation of bacterial morphological transitions during cell infection.

No specific time window distinguishes between community-, healthcare-, and hospital-acquired bacteremia, but they are prognostically robust

OBJECTIVE

We examined whether specific time windows after hospital admission reflected a sharp transition between community and hospital acquisition of bacteremia. We further examined whether different time windows to distinguish between community acquisition, healthcare association (HCA), and hospital acquisition influenced the results of prognostic models.

DESIGN

Population-based cohort study.

SETTING

Hospitals in 3 areas of Denmark (2.3 million inhabitants) during 2000-2011.

METHODS

We computed graphs depicting proportions of males, absence of comorbidity, microorganisms, and 30-day mortality pertaining to bacteremia 0, 1, 2, …, 30, and 31 days and later after admission. Next, we assessed whether different admission (0-1, 0-2, 0-3, 0-7 days) and HCA (30, 90 days) time windows were associated with changes in odds ratio (OR) and area under the receiver operating characteristic (ROC) curve for 30-day mortality, adjusting for sex, age, comorbidity, and microorganisms.

RESULTS

For 56,606 bacteremic episodes, no sharp transitions were detected on a specific day after admission. Among the 8 combined time windows, ORs for 30-day mortality varied from 1.30 (95% confidence interval [CI], 1.23-1.37) to 1.99 (95% CI, 1.48-2.67) for HCA and from 1.36 (95% CI, 1.24-1.50) to 2.53 (95% CI, 2.01-3.20) for hospital acquisition compared with community acquisition. Area under the ROC curve changed marginally from 0.684 (95% CI, 0.679-0.689) to 0.700 (95% CI, 0.695-0.705).

CONCLUSIONS

No time transitions unanimously distinguished between community and hospital acquisition with regard to sex, comorbidity, or microorganisms, and no difference in 30-day mortality was seen for HCA patients in relation to a 30- or 90-day time window. ORs decreased consistently in the order of hospital acquisition, HCA, and community acquisition, regardless of time window combination, and differences in area under the ROC curve were immaterial.

Bacteremia is associated with excess long-term mortality: a 12-year population-based cohort study

OBJECTIVES

Little is known about long-term outcomes following bacteremia. We investigated long-term mortality and causes of death among bacteremia patients compared with population controls.

METHODS

Population-based cohort study of bacteremia patients and population controls matched on sex, year of birth, residency and calendar time, in Denmark during 2000-2008. We calculated absolute mortality and adjusted mortality rate ratios (MRRs) in predefined follow-up periods.

RESULTS

The absolute mortality for bacteremia patients (n = 7783) and population controls (n = 38,906) was 22.0% vs. 0.2% (30 days), 41.4% vs. 2.6% (1 year) and 75.8% vs. 36.6% (10 years). For bacteremia patients, the MRR was 115.3 (95% CI, 88.2-150.9) 0-30 days after bacteremia and 2.1 (95% CI, 1.8-2.3) from 5 years to end of follow-up. The most common causes of death were cancer and cardiovascular diseases. Within one year of bacteremia, the relative risk of death was highest for genitourinary diseases and infectious diseases. Among one-year survivors of bacteremia, the relative risk of death was increased for all major causes of death.

CONCLUSIONS

Bacteremia is associated with a poor prognosis and considerable excess long-term mortality compared with the general population. The most common causes of death after bacteremia are cancer and cardiovascular diseases.

SUMMARY

This population-based cohort study reports an excess long-term mortality among 7783 bacteremia patients compared with matched population controls during 12 years of follow-up. We identified patients in particular risk of death and reported novel information on causes of death.

Combination therapy with thioridazine and dicloxacillin combats meticillin-resistant Staphylococcus aureus infection in Caenorhabditis elegans

The shortage of drugs active against meticillin-resistant Staphylococcus aureus (MRSA) is a growing clinical problem. In vitro studies indicate that the phenothiazine thioridazine (TZ) might enhance the activity of the β-lactam antibiotic dicloxacillin (DCX) to a level where MRSA is killed, but experiments in simple animal models have not been performed. In the present study, we introduced Caenorhabditis elegans infected by S. aureus as an in vivo model to test the effect of TZ as a helper drug in combination with DCX. Because TZ is an anthelmintic, initial experiments were carried out to define the thresholds of toxicity, determined by larval development, and induction of stress-response markers. No measurable effects were seen at concentrations of less than 64 mg TZ l−1. Seven different MRSA strains were tested for pathogenicity against C. elegans, and the most virulent strain (ATCC 33591) was selected for further analyses. In a final experiment, full-grown C. elegans were exposed to the test strain for 3 days and subsequently treated with 8 mg DCX l−1 and 8 mg TZ l−1 for 2 days. This resulted in a 14-fold reduction in the intestinal MRSA load as compared with untreated controls. Each drug alone resulted in a two- to threefold reduction in MRSA load. In conclusion, C. elegans can be used as a simple model to test synergy between DCX and TZ against MRSA. The previously demonstrated in vitro synergy can be reproduced in vivo.

Agreement between public register and adjudication committee outcome in a cardiovascular randomized clinical trial

The objective of this study is to describe the agreement between randomized trial outcome assessment by committee and outcomes entirely identified through public registers.

METHODS

In the CLARICOR trial, 4,372 patients with stable coronary heart disease received a short course of clarithromycin versus placebo and were followed up for 2.6 years. The pertinent hospital records and death certificates had originally been evaluated by the adjudication committee using common definitions of outcomes mapped into a 6-category list. We now mechanically converted the International Classification of Diseases-coded diagnoses of the public registries into the same categories. After cross-tabulation of the committee diagnoses with National Patient Register diagnoses and Register of Causes of Death, we calculate agreement and compare the estimated intervention effects of the 2 data sets.

RESULTS

With public register data, the protocol-specified categories were slightly more frequent. Overall agreement was 74% for hospital discharges and 60% for cause of death, but the intervention effect, expressed as a hazard ratio, stayed within 4% of the value originally obtained with the adjudication committee (P ≥ .35).

CONCLUSIONS

Our results show a modest agreement between formal adjudication and outcomes deducible from public registers. However, the estimated intervention effect did not differ noticeably between the 2 data sources. If studies on a wide range of public registers confirm these findings, register outcomes may be considered as a replacement for adjudication committees.

How do bacteraemic patients present to the emergency department and what is the diagnostic validity of the clinical parameters; temperature, C-reactive protein and systemic inflammatory response syndrome?

Objective

Although blood cultures are often ordered based on the presence of fever, it is a clinical challenge to identify patients eligible for blood cultures. Our aim was to evaluate the diagnostic value of temperature, C-reactive-protein (CRP), and Systemic Inflammatory Response Syndrome (SIRS) to identify bacteraemic patients in the Medical Emergency Department (MED).

Methods

A population-based cohort study including all adult patients at the MED at Odense University Hospital between August 1st 2009 - August 31st 2011.

Results

11,988 patients were admitted to the MED within the study period. Blood cultures were performed on 5,499 (45.9%) patients within 2 days of arrival, of which 418 (7.6%) patients were diagnosed with bacteraemia. This corresponded to 3.5% of all patients. 34.1% of the bacteraemic patients had a normal rectal temperature (36.0°–38.0°C) recorded at arrival, 32.6% had a CRP < 100 mg/L and 28.0% did not fulfil the SIRS criteria.

For a temperature cut-point of >38.0°C sensitivity was 0.64 (95% CI 0.59–0.69) and specificity was 0.81 (0.80–0.82) to identify bacteraemic patients.

Conclusion

One third of the acute medical bacteraemic patients had a normal temperature at arrival to the MED. A normal temperature combined with a CRP < 100 mg/L and no SIRS criteria, ruled out bacteraemia.

Decreasing incidence rates of bacteremia: a 9-year population-based study

BACKGROUND

Numerous studies have shown that the incidence rate of bacteremia has been increasing over time. However, few studies have distinguished between community-acquired, healthcare-associated and nosocomial bacteremia.

METHODS

We conducted a population-based study among adults with first-time bacteremia in Funen County, Denmark, during 2000-2008 (N = 7786). We reported mean and annual incidence rates (per 100,000 person-years), overall and by place of acquisition. Trends were estimated using a Poisson regression model.

RESULTS

The overall incidence rate was 215.7, including 99.0 for community-acquired, 50.0 for healthcare-associated and 66.7 for nosocomial bacteremia. During 2000-2008, the overall incidence rate decreased by 23.3% from 254.1 to 198.8 (3.3% annually, p < .001), the incidence rate of community-acquired bacteremia decreased by 25.6% from 119.0 to 93.8 (3.7% annually, p < .001) and the incidence rate of nosocomial bacteremia decreased by 28.9% from 82.2 to 56.0 (4.2% annually, p < .001). The incidence rate of healthcare-associated bacteremia remained stable. The most common microorganisms were Escherichia coli (28.3%), Staphylococcus aureus (12.3%), coagulase-negative staphylococci (10.0%) and Streptococcus pneumoniae (9.1%). Regardless of place of acquisition, the proportion of bacteremias caused by enterococci increased (p < .05) and the proportion caused by coagulase-negative staphylococci decreased (p < .05).

CONCLUSIONS

The incidence rates of community-acquired and nosocomial bacteremia decreased substantially over time.

[Elderly patients are at high risk from hospital-acquired infection]

Hospital-acquired infections cause considerable morbidity and mortality in elderly patients and burden the individual patient as well as the economy of society. Although these infections are linked to biological factors in elderly patients, there is a potential for increased prevention efforts. Changes in antibiotic policy and organisational tasks can reduce the spread of drug resistant bacteria causing serious nosocomial infections. Transmission of pathogens from hospitals to nursing homes and vice versa poses a particular challenge when dealing with elderly colonized or infected patients.

Characteristics of patients with community-acquired bacteremia who have low levels of C-reactive protein (≤20 mg/L)

OBJECTIVES

To characterize patients presenting with community-acquired bacteremia and a low C-reactive protein (CRP) plasma level at date of bacteremia.

METHODS

Population-based cohort study. Patient characteristics were compared for three CRP groups (≤20 mg/L, 21-100 mg/L and >100 mg/L) using chi-square test and oneway anova. The 30-day mortality rates were compared using logistic regression analyses.

RESULTS

Of the 2017 patients included, 193 (9.6%) had a CRP ≤20 mg/L. These patients were younger, more likely to be male, overrepresented in the intensive care unit and had more comorbidities. In blood cultures from the low CRP group hemolytic streptococci and coagulase-negative staphylococci were found relatively more common, whereas Streptococcus pneumoniae or Staphylococcus aureus were found relatively less common compared to the other CRP groups. The majority of patients with an initial low CRP mounted a CRP response the following days. The 30-day mortality rate was lower in the low CRP group (13.5%) than in the group with CRP >100 mg/L (20.6%).

CONCLUSIONS

A considerable proportion of patients with community-acquired bacteremia has a normal or low initial CRP level. The plasma CRP level should not be used to rule out serious infection or withhold antibiotic therapy.

Risk stratification in stable coronary artery disease is possible at cardiac troponin levels below conventional detection and is improved by use of N-terminal pro-B-type natriuretic peptide

AIMS

Low prevalence of detectable cardiac troponin in healthy people and low-risk patients previously curtailed its use. With a new high-sensitive cardiac troponin assay (hs-cTnT), concentrations below conventional detection may have prognostic value, notably in combination with N-terminal pro-B-type natriuretic peptide (NT-pro-BNP).

METHODS AND RESULTS

Biomarker concentrations were determined from serum obtained at enrolment in the CLARICOR trial involving 4197 patients with stable coronary artery disease (CAD) followed for 2.6 years. Serum hs-cTnT was detectable (above 3 ng/l) in 78% and above the conventional 99th percentile (13.5 ng/l) in 23%. Across all levels of hs-cTnT there was a graded increase in the risk of cardiovascular death after adjustment for known prognostic indicators: hazard ratio (HR) per unit increase in the natural logarithm of the hs-cTnT level, 1.49; 95% confidence interval (CI), 1.23-1.81; similarly for all-cause mortality (HR 1.48, 95% CI 1.29-1.70) and myocardial infarction (HR 1.37, 95% CI 1.13-1.67). Increasing values of hs-cTnT were associated with increased mortality across all values of NT-pro-BNP, but this was particularly prominent when NT-pro-BNP >400 ng/l.

CONCLUSIONS

In patients with stable CAD, any detectable hs-cTnT level is significantly associated with all-cause mortality, cardiovascular death, and myocardial infarction after adjustment for traditional risk factors and NT-pro-BNP. Excess mortality is particularly pronounced in patients with NT-pro-BNP >400 ng/l.

Thioridazine potentiates the effect of a beta-lactam antibiotic against Staphylococcus aureus independently of mecA expression

The neuroleptic antipsychotic derivate thioridazine has been shown to increase the susceptibility of a methicillin-resistant Staphylococcus aureus (MRSA) isolate towards dicloxacillin. The aim of this study was to investigate the combinatorial effect of the two drugs on a broad selection of staphylococcal strains by analyzing a large collection of MRSA strains carrying different types of SCCmec, as well as MSSA strains. Transcription and translation of the resistance marker PBP2a encoded by mecA within the SCCmec cassette were analyzed by primer extension and western blotting. We observed increased susceptibility to dicloxacillin in the presence of thioridazine in all tested MRSA isolates. In contrast to previously published results, the synergistic effect was also applicable to methicillin-susceptible S. aureus (MSSA). We conclude that the combination of dicloxacillin and thioridazine potentiates the killing effect against S. aureus in a broad selection of clinical isolates. Additionally, the study indicates that the killing effect by the combinatorial treatment is independent of PBP2a-mediated resistance mechanisms.

Bacteremia with Streptococcus pneumoniae: sepsis and other risk factors for 30-day mortality--a hospital-based cohort study

We conducted a hospital-based cohort study among adult patients with first-time Streptococcus pneumoniae bacteremia (SPB) from 2000 through 2008. Patients were identified in a population-based bacteremia database and followed up for mortality through the Danish Civil Registration System (CRS). The aim of the study was to determine the focal diagnosis of SPB, the severity of sepsis at presentation, demographics and comorbidity characteristics of the patients, and to determine the 30-day mortality rate and factors related to mortality. We identified 481 patients, of which 238 were males. The mean age of the patients was 65 years. The focal diagnosis of the SPB was pneumonia in 381 (79 %) patients, followed in frequency by meningitis in 33 (7 %) patients. Of the 481 patients, 390 (81 %) had community-acquired SPB. Of these, 23 (6 %) did not have sepsis, 132 (34 %) had sepsis, 224 (57 %) had severe sepsis, and 11 (3 %) were in septic shock. Overall, the 30-day mortality was 16 %. Mortality increased with the severity of sepsis. There was no association between the focal diagnosis of SPB or the number of diagnoses and mortality. Nosocomial infection, male sex, increasing age, and increasing comorbidity were all associated with an increased 30-day mortality rate.

[Selection and spreading of antibiotic resistance in bacteria]

Use of an antibiotic may not only select for resistance against the agent itself, but may at the same time co-select for resistance against other antibiotics if resistance genes are linked on e.g. a plasmid. Resistance plasmids may also carry genes mediating resistance against metals and disinfectants. Therefore, abundant use of metals, e.g. copper and zinc for growth promotion in animals used for food, may also co-select for antibiotic resistance. The same applies to disinfectants, e.g. silver and chlorhexidine. Prudent use of antibiotics and these other agents is essential to control antibiotic resistance.

[Rational antibiotic treatment can be achieved through audits and teaching]

A prerequisite for rational antibiotic treatment is the suspicion that the disease is caused by bacteria and that treatment will reduce symptoms and complications. In primary health care most infections are caused by bacteria. The European project HAPPY AUDIT found that an intervention targeting doctors and patients in primary care led to a considerable decrease in antibiotic prescribing. Teaching of hospital doctors, combined with a restriction in the choice of antibiotics, resulted in a decrease in multidrug-resistant strains. A concerted effort is needed to curb the growing resistance problem.

The effect of honey-coated bandages compared with silver-coated bandages on treatment of malignant wounds-a randomized study

Malignant wounds (MWs) occur in 5-10% of all cancer patients. Malodor and exudation are the most common side effects. The aim was to determine the influence of honey-coated compared with silver-coated bandages on treatment of MWs. Patients were randomly selected to enter either group A (honey-coated bandages) or group B (silver-coated bandages). Parameters were the following: wound size, cleanliness, malodor, exudation, and wound pain. Digital photographs, visual analog scales (VAS), and wound morphology registration were used for measurement at baseline and following the 4-week intervention. Sixty-nine patients with MWs and advanced cancer, aged 47-90 (median 65.6), were included. No statistically significant difference was noted between the groups with respect to wound size, degree of cleanliness, exudation, malodor, and wound pain. There was a median decrease in wound size of 15 cm² and 8 cm² in group A and B, respectively (p = 0.63). Based on post-intervention pooled data from the groups, improvement was seen in 62% of the participants with respect to wound size and in 58% (n = 69) with respect to cleanliness. The VAS score for malodor (p = 0.007) and exudation (p < 0.0001) improved significantly post-intervention. Patients with reduced wound size had a median survival time of 387 days compared with 134 days in patients with no wound reduction (p = 0.003). The use of honey-coated and silver-coated bandages improved the outcome of MWs. No differences were found between the two regimens. Both types of bandages are recommended for use by patients with MWs containing tumor debris and necrosis.

Thioridazine affects transcription of genes involved in cell wall biosynthesis in methicillin-resistant Staphylococcus aureus

The antipsychotic drug thioridazine is a candidate drug for an alternative treatment of infections caused by methicillin-resistant Staphylococcus aureus (MRSA) in combination with the β-lactam antibiotic oxacillin. The drug has been shown to have the capability to resensitize MRSA to oxacillin. We have previously shown that the expression of some resistance genes is abolished after treatment with thioridazine and oxacillin. To further understand the mechanism underlying the reversal of resistance, we tested the expression of genes involved in antibiotic resistance and cell wall biosynthesis in response to thioridazine in combination with oxacillin. We observed that the oxacillin-induced expression of genes belonging to the VraSR regulon is reduced by the addition of thioridazine. The exclusion of such key factors involved in cell wall biosynthesis will most likely lead to a weakened cell wall and affect the ability of the bacteria to sustain oxacillin treatment. Furthermore, we found that thioridazine itself reduces the expression level of selected virulence genes and that selected toxin genes are not induced by thioridazine. In the present study, we find indications that the mechanism underlying reversal of resistance by thioridazine relies on decreased expression of specific genes involved in cell wall biosynthesis.