Disease burden of bacteraemia with extended-spectrum beta-lactamase-producing and carbapenem-resistant Enterobacterales in Korea

BACKGROUND

Despite the significant impact of multi-drug-resistant bacteraemia, especially extended-spectrum beta-lactamase-producing Enterobacterales (ESBL-E) and carbapenem-resistant Enterobacterales (CRE), the burden of disease has not been investigated thoroughly.

AIM

To evaluate the clinical outcomes and socio-economic burden of ESBL-E and CRE bacteraemia nationwide in the Republic of Korea.

METHODS

A search was undertaken for all cases of ESBL-E and CRE bacteraemia and matched controls in 10 hospitals in the Republic of Korea over 6 months. Patients with ESBL-E or CRE bacteraemia were classified as the R group, and matched controls with antibiotic-susceptible bacteraemia and without infection were classified as the S and N groups, respectively. Patients' clinical data were collected, and the economic burden was estimated based on medical expenses, loss of productivity and total costs.

FINDINGS

In total, 795 patients were identified, including 265 patients with ESBL-E or CRE bacteraemia and their matched controls. The mean total length of stay for patients with ESBL-E and CRE in the R group was 1.53 and 1.90 times that of patients in the S group, respectively. The 90-day mortality rates for ESBL-E in the R and S groups were 12.1% and 5.6%, respectively, and the corresponding figures for CRE were 28.6% and 12.0%. There were significant differences in the total costs between the R, S and N groups for both ESBL-E and CRE (ESBL-E: $11,151 vs $8712 vs $6063, P=0.004; CRE: $40,464 vs $8748 vs $7279, P=0.024).

CONCLUSION

The clinical and economic burden imposed by ESBL-E or CRE bacteraemia was extremely high. These findings suggest that efforts to control resistant bacteraemia are necessary to reduce this burden.

An extremely energetic cosmic ray observed by a surface detector array

Cosmic rays are energetic charged particles from extraterrestrial sources, with the highest-energy events thought to come from extragalactic sources. Their arrival is infrequent, so detection requires instruments with large collecting areas. In this work, we report the detection of an extremely energetic particle recorded by the surface detector array of the Telescope Array experiment. We calculate the particle's energy as [Formula: see text] (~40 joules). Its arrival direction points back to a void in the large-scale structure of the Universe. Possible explanations include a large deflection by the foreground magnetic field, an unidentified source in the local extragalactic neighborhood, or an incomplete knowledge of particle physics.

Appropriateness of antibiotic use for patients with asymptomatic bacteriuria or urinary tract infection with positive urine culture: a retrospective observational multi-centre study in Korea

BACKGROUND

Antibiotic resistance threatens public health worldwide, and inappropriate use of antibiotics is one of the main causes.

AIM

To evaluate qualitative use of antibiotics in asymptomatic bacteriuria (ABU) and urinary tract infection (UTI).

METHODS

Cases of positive urine culture (≥105 colony-forning units/mL) performed in inpatient, outpatient and emergency departments in April 2021 were screened in 26 hospitals in the Republic of Korea. The cases were classified as ABU, lower UTI and upper UTI. The appropriateness of antibiotic use was evaluated retrospectively by infectious disease specialists using quality indicators based on clinical guidelines for ABU and UTI.

RESULTS

This study included a total of 2697 patients with ABU or UTI. The appropriateness of antibiotic use was assessed in 1157 patients with ABU, and in 677 and 863 patients with lower and upper UTI, respectively. Among the 1157 patients with ABU, 251 (22%) were prescribed antibiotics without appropriate indications. In 66 patients with ABU in which antibiotics were prescribed with appropriate indications, the duration was adequate in only 23 (34.8%) patients. The appropriateness of empirical and definite antibiotics was noted in 527 (77.8%) and 353 (68.0%) patients with lower UTI, and 745 (86.3%) and 583 (78.2%) patients with upper UTI, respectively. The duration of antibiotics was adequate in 321 (61.8%) patients with lower UTI and 576 (78.7%) patients with upper UTI.

CONCLUSIONS

This nationwide qualitative assessment of antibiotic use in ABU and UTI revealed that antibiotics were often prescribed inappropriately, and the duration of antibiotics was unnecessarily prolonged.

Applicability and limitations of quality indicator-based assessment of appropriateness in antimicrobial use: a comparison with expert opinion

BACKGROUND

The effective implementation of antimicrobial stewardship requires an a-priori assessment of the appropriateness of antimicrobial prescriptions.

AIM

To evaluate the effectiveness of quality indicators (QIs) in determining the appropriateness of antimicrobial prescriptions compared to that of expert opinions.

METHODS

The study assessed antimicrobial use in 20 hospitals in Korea, with infectious disease specialists rating the appropriateness based on QIs and expert opinions. The selected QIs were (1) taking two blood cultures, (2) taking cultures from suspected sites of infection, (3) prescribing empirical antimicrobials according to guidelines, and (4) changing from empirical to pathogen-directed therapy for hospitalized patients and (2, 3, and 4) for ambulatory patients. Applicability, compliance with QIs, and agreement between QIs and expert opinions were investigated.

FINDINGS

Overall, 7999 therapeutic uses of antimicrobials were investigated at the study hospitals. The experts rated 20.5% (1636/7999) as inappropriate use. For hospitalized patients, antimicrobial use was assessed based on all four QIs in 28.8% (1798/6234) of the cases. For ambulatory care patients, only 7.5% (102/1351) of the antimicrobial use cases were assessed using all three QIs. The agreement between expert opinions and all four QIs for hospitalized patients was minimal (κ = 0.332), whereas that between expert opinions and all three QIs for ambulatory patients was weak (κ = 0.598).

CONCLUSION

QIs have limitations in determining the appropriateness of antimicrobial use, and the degree of agreement with expert opinions was low. Therefore, these QI limitations should be considered when determining the appropriateness of antimicrobial use.

Regional and annual patterns in respiratory virus co-infection etiologies and antibiotic prescriptions for pediatric mycoplasma pneumoniae pneumonia

OBJECTIVE

Mycoplasma pneumoniae (M. pneumoniae) pneumonia is the second-most common cause of community-acquired pneumonia (CAP). This study aimed at investigating into the prevalence of macrolide-resistant M. pneumoniae (MRMP) with respiratory virus co-infection and the antibiotic prescriptions in children with CAP in four provinces in Korea, and to assess the variations in the findings across regions and throughout the year.

PATIENTS AND METHODS

This prospective study was conducted in 29 hospitals in Korea between July 2018 and June 2020. Among the enrolled 1,063 children with CAP, all 451 patients with M. pneumoniae underwent PCR assays of M. pneumoniae and respiratory viruses, and the presence of point mutations of residues 2063 and 2064 was evaluated.

RESULTS

Gwangju-Honam (88.6%) showed the highest prevalence of MRMP pneumonia, while Daejeon-Chungcheong (71.3%) showed the lowest, although the differences in prevalence were not significant (p=0.074). Co-infection of M. pneumoniae pneumonia and respiratory virus was observed in 206 patients (45.4%), and rhinovirus co-infection (101 children; 22.2%) was the most frequent. The prevalence of MRMP pneumonia with respiratory virus co-infection and the antibiotic prescriptions differed significantly among the four provinces (p < 0.05). The monthly rate of MRMP pneumonia cases among all cases of M. pneumoniae pneumonia and tetracycline or quinolone prescriptions did not differ significantly among the four regions (trend p > 0.05) during the study period.

CONCLUSIONS

The prevalence of M. pneumoniae pneumonia with virus co-infection and antibiotic prescriptions could differ according to region, although the MRMP pneumonia rate showed no difference within Korea.

Effect of iron deficiency without anaemia on days alive and out of hospital in patients undergoing valvular heart surgery

Comprehensive evidence regarding the treatment of non-anaemic iron deficiency in patients undergoing valvular heart surgery is lacking. This study aimed to investigate the association between non-anaemic iron deficiency and postoperative outcomes in these patients. We retrospectively analysed 321 patients of which 180 (56%) had iron deficiency (defined as serum ferritin < 100 ng.ml^-1 or < 300 ng.ml^-1 with transferrin saturation < 20%). While the iron-deficient group had lower pre-operative haemoglobin levels than the non-iron deficient group (median (IQR [range]) 134 (127-141 [120-172]) g.l^-1 , 143 (133-150 [120-179]) g.l^-1 , p = 0.001), there was no between-group difference in allogeneic red blood cell transfusion. Median (IQR [range]) days alive and out of hospital at postoperative day 90 was 1 day shorter in the iron-deficient group (80 (77-82 [9-85]) days vs. 81 (79-83 [0-85]) days, p = 0.026). In multivariable analysis, only cardiopulmonary bypass duration (p = 0.032) and intra-operative allogeneic red blood cell transfusion (p = 0.011) were significantly associated with reduced days alive and out of hospital at postoperative day 90. Iron deficiency did not exert any adverse influence on secondary outcomes except length of hospital stay. Our findings indicate that non-anaemic iron deficiency alone is not associated with adverse effects in patients undergoing valvular heart surgery when it does not translate into an increased risk of allogeneic transfusion.

Aβ Accumulation in Vmo Contributes to Masticatory Dysfunction in 5XFAD Mice

Alzheimer's disease (AD) shows various symptoms that reflect cognitive impairment and loss of neural circuit integrity. Sensory dysfunctions such as olfactory and ocular pathology are also observed and used as indicators for early detection of AD. Although mastication is suggested to correlate with AD progression, changes in the masticatory system have yet to be established in transgenic animal models of AD. In the present study, we have assessed pathologic hallmarks of AD with the masticatory behavior of 5XFAD mice. We found that masticatory efficiency and maximum biting force were decreased in 5XFAD mice, with no significant change in general motor function. Immunohistochemical analysis revealed significant accumulation of Aβ (amyloid β), increased microglia number, and cell death in Vmo (trigeminal motor nucleus) as compared with other cranial motor nuclei that innervate the orofacial region. Masseter muscle weight and muscle fiber size were also decreased in 5XFAD mice. Taken together, our results demonstrate that Aβ accumulation in Vmo contributes to masticatory dysfunction in 5XFAD mice, suggesting a close association between masticatory dysfunction and dementia.

Associations of serum monocyte-to-high-density lipoprotein cholesterol ratio with digital ulcers and skin fibrosis in patients with systemic sclerosis

Objective: To investigate the relationship between the monocyte-to-high-density lipoprotein cholesterol ratio (MHR) and clinical manifestations in patients with systemic sclerosis (SSc).Method: This was a cross-sectional analysis of a cohort study comprising 111 female SSc patients recruited from a tertiary care rheumatology centre. We also assessed 222 age-matched female healthy controls. Serum MHR was measured in all study participants. Digital ulcer (DU) was defined as an active or healed ulceration, and the magnitude of skin fibrosis was determined according to the modified Rodnan skin score (mRSS).Results: The mean age and median disease duration in patients with SSc were 56.3 years and 98 months, respectively. The MHR in SSc patients was significantly higher than that in controls. DU was found in 35 patients (31.5%) with SSc (active in 12 and healed in 23), and the median mRSS was 8. SSc patients with DU had a significantly higher median MHR than those without (11.43 vs 7.62, p < 0.001), and MHR significantly positively correlated with mRSS (ρ = 0.289, p = 0.002). Multivariable logistic regression revealed that an elevated MHR was independently associated with increased risk of DU (odds ratio = 1.21; 95% confidence interval = 1.07-1.35; p = 0.002). In the multivariable linear regression analysis, higher MHR showed a significant association with increased log-transformed mRSS (unstandardized β = 0.052, p = 0.003).Conclusion: Our findings suggest that the MHR could be serve as a potential biomarker of the risk of DU and advanced skin fibrosis in patients with SSc.

Long-term exposure to air pollution and the risk of non-lung cancer: a meta-analysis of observational studies

AIMS

Several meta-analyses of observational studies report a long-term correlation between air pollution and the risk of cancer, particularly lung carcinoma. The aim of this study was to review and quantify evidence for an association between air pollution and the risk of developing non-lung cancers.

METHODS

We searched PubMed, EMBASE, Cochrane Library, and the reference lists of the included studies as well as those recorded in previous meta-analyses conducted before January 2019. A random-effects model was used to derive overall risk estimates per pollutant.

RESULTS

A total of 20 studies, including 5 case-control and 15 prospective cohort studies, were used in the final analysis. The risk of developing non-lung cancer was 1.09 (95% confidence interval (CI): 1.01-1.18, I² = 72.9%) per NO₂ increases of 10 µg/m³. There was also a significant association between exposure to PM_2.5 and PM₁₀ and the risk of non-lung cancer when the male and female populations were combined (pooled odds ratio/relative risk (OR/RR) = 1.22, 95% CI: 1.11-1.34; I² = 0.0% and pooled OR/RR = 1.26, 95% CI: 1.05-1.52; I² = 43.9%, respectively). Regarding the type of cancer, significant harmful effects of PM_2.5 were observed for liver cancer populations (pooled OR/RR = 1.21, 95% CI: 1.10-1.32; I² = 0.0%). Different types of cancer were positively associated with the incidence of non-lung cancer and PM₁₀ in the random-effect meta-regression analysis.

CONCLUSIONS

Long-term exposure to air pollutants appears to be associated with an increased risk of non-lung cancer. Care should be taken in interpretation, because the results for specific cancers were restricted.

TRPM8 Mediates Hyperosmotic Stimuli-Induced Nociception in Dental Afferents

Hyperosmolar sweet foods onto exposed tooth dentin evoke sudden and intense dental pain, called dentin hypersensitivity. However, it remains unclear how hyperosmolar stimuli excite dental primary afferent (DPA) neurons and thereby lead to dentin hypersensitivity. This study elucidated whether TRPM8, which is well known as a cold temperature- or menthol-activated receptor, additionally mediates nociception in response to hyperosmolar stimuli in adult mouse DPA neurons, which are identified by a fluorescent retrograde tracer: DiI. Single-cell reverse transcription polymerase chain reaction revealed that TRPM8 was expressed in subsets of DPA neurons and that TRPM8 was highly colocalized with TRPV1 and Piezo2. Immunohistochemical analysis also confirmed TRPM8 expression in DPA neurons. By using Fura-2-based calcium imaging, application of hyperosmolar sucrose solutions elicited calcium transients in subsets of the trigeminal ganglion neurons, which was significantly abolished by a selective TRPM8 antagonist: N-(3-Aminopropyl)-2-[(3-methylphenyl)methoxy]-N-(2-thienylmethyl)benzamide (AMTB) hydrochloride. When we further examined changes of c-fos expression (a neuronal activation marker) in the spinal trigeminal nucleus after hyperosmolar stimulation onto exposed tooth dentin, c-fos mRNA and protein expression were increased and were also significantly reduced by AMTB, especially in the spinal trigeminal interpolaris-caudalis transition zone (Vi/Vc). Taken together, our results provide strong evidence that TRPM8 expressed in DPA neurons might mediate dental pain as a hyperosmosensor in adult mice.

Effect of carvacrol essential oils on immune response and inflammation-related genes expression in broilers challenged by lipopolysaccharide

This experiment was conducted to study the effects of orally administered carvacrol essential oils on immune response and inflammation-related genes expression in broilers challenged by lipopolysaccharide (LPS). Eighty 28-day-old (1.28 ± 0.15 kg) ROSS 308 broilers were assigned to a 2 × 2 factorial arrangement of treatments (20 pens of 1 chick/trt). Factors were carvacrol essential oil (orally administered or non-orally administered) and LPS (challenged or non-challenged). Individually housed broilers were randomly assigned (n = 20 broilers per treatment: 10 males and 10 females) to four treatments: (1) basic diet (CTR), (2) basic diet + carvacrol (CAR), (3) basic diet + LPS-challenge (LPS), (4) basic diet + carvacrol + LPS-challenge (CAR+LPS). All were fed with the same diet. The experimental period was for 15 d, after which injecting LPS significantly up-regulated the gene expression levels of TNF-α (P < 0.05), IL-1β (P < 0.05), IL-6 (P < 0.05), IL-8 (P < 0.05), TLR2 (P < 0.05), TLR4 (P < 0.05), NF-κB p65 (P < 0.05), AVBD-9 (P < 0.05), and SIgA(P < 0.05) compared with the CTR group; the broilers were challenged by LPS after oral administration of carvacrol, they had significant lower on the gene expression levels of TNF-α (P < 0.05), IL-1β (P < 0.05), IL-6 (P < 0.05), TLR4 (P < 0.05), NF-κB p65 (P < 0.05), and AVBD-9 (P < 0.05) than the LPS group. In conclusion, the broilers orally administrated carvacrol essential oils inhibited the secretion of inflammatory cytokines caused by LPS, affected the pathway of TLRs/NF-κB, and showed an anti-inflammatory function.

Efficacy and safety of transarterial chemoembolisation with cone-beam CT in patients with hepatocellular carcinoma within the Milan criteria: a retrospective cohort study

AIM

To compare the therapeutic efficacy and safety of transarterial chemoembolisation (TACE) for hepatocellular carcinoma (HCC) within the Milan criteria with or without the use of cone-beam computed tomography (CBCT).

MATERIALS AND METHODS

Patients with HCC within the Milan criteria who underwent conventional angiography-guided TACE (Angio-TACE group: 58 patients from January 2010 to December 2011) were compared with those who underwent CBCT-guided TACE (CBCT-TACE group: 55 patients from January 2013 to December 2014). Local progression-free survival (LPFS), progression-free survival (PFS), and overall survival (OS) were compared. Adverse events after TACE were also investigated.

RESULTS

Baseline characteristics were balanced between the two groups. LPFS was significantly longer in the CBCT-TACE group than in the Angio-TACE group (median: not reached for 36 versus 19.2 months, respectively; Log-rank p=0.029). In multivariable Cox regression analysis, CBCT guidance had a significantly lower risk of local progression or death (adjusted hazard ratio: 0.585; 95% confidence interval, 0.344-0.995; p=0.048); however, there was no significant difference in PFS (3-year PFS: 15.9% versus 26.8%, respectively; p=0.122) or OS (3-year OS: 85% versus 88.2%, respectively; p=0.761) between the Angio-TACE and CBCT-TACE groups. Post-embolisation syndrome occurred significantly less frequently in the CBCT-TACE group (p=0.002).

CONCLUSION

CBCT-guided TACE could improve local tumour control for HCC within Milan criteria and showed fewer cases of post-embolisation syndrome.

Impact of antimicrobial treatment duration on outcome of Staphylococcus aureus bacteraemia: a cohort study

OBJECTIVES

To assess the outcome of Staphylococcus aureus bacteraemia (SAB) according to factors associated with necessity for longer treatment in conjunction with the duration of treatment.

METHODS

We prospectively collected the data of patients with SAB consecutively during 12 to 39 months from 11 hospitals. If multiple episodes of SAB occurred in one patient, only the first episode was enrolled. Factors associated with necessity for longer treatment were defined as follows: persistent bacteraemia, metastatic infection, prosthesis and endocarditis. If any of the factors were present, then the case was defined as longer antibiotic treatment warranted (LW) group; those without any factors were defined as shorter antibiotic treatment sufficient (SS) group. Poor outcome was defined as a composite of 90-day mortality or 30-day recurrence. Duration of antibiotic administration was classified as <14 or ≥14 days in the SS group and <28 or ≥28 days in the LW group.

RESULTS

Among 2098 cases, the outcome was analysed in 1866 cases, of which 591 showed poor outcome. The SS group accounted for 964 cases and the LW group for 852. On multivariate analysis, age over 65 years, pneumonia, higher Sequential Organ Failure Assessment (SOFA) score and chronic liver diseases were risk factors for poor outcome. Administration of antibiotics less than the recommendation was associated with poor outcome, but this significance was observed only in the LW group (adjusted odds ratio = 1.68; 95% confidence interval, 1.00-2.83; p 0.05).

CONCLUSIONS

Inappropriately short antibiotic treatment was associated with poor outcome in the LW group. Vigilant evaluation for risk factors to determine the duration of treatment may improve the outcome among patients with SAB.

Active surveillance for carbapenem-resistant Enterobacteriaceae, vancomycin-resistant enterococci and toxigenic Clostridium difficile among patients transferred from long-term care facilities in Korea

A 10-month active surveillance study was conducted to assess carriage of carbapenemase-producing Enterobacteriaceae (CPE), vancomycin-resistant enterococci (VRE) and toxigenic Clostridium difficile colonization among patients transferred to hospital from long-term care facilities (LTCFs). Four (1.4%) patients with carbapenem-resistant Enterobacteriaceae (none of which were CPE), 59 (21%) patients with VRE and 20 (7.1%) patients colonized with toxigenic C. difficile were identified from 282 rectal specimens. There was no outbreak of VRE infection during the study period. The low prevalence of CPE carriage suggests that screening all admissions from LTCFs for CPE would not be cost-effective, and that screening and use of contact precautions for VRE should be reconsidered.

Efficacy of vitamin D supplementation in combination with conventional antiviral therapy in patients with chronic hepatitis C infection: a meta-analysis of randomised controlled trials

BACKGROUND

Although a contributory role of vitamin D levels for the development of chronic hepatitis C has been suggested, the efficacy of vitamin D supplementation in combination with conventional antiviral therapy consisting of pegylated interferon-α (Peg-IFN-α) injection and oral ribavirin (RBV) remains unclear. We investigated its efficacy in the treatment of chronic hepatitis C via a meta-analysis of randomised controlled trials.

METHODS

We searched PubMed, EMBASE, the Cochrane Library, ClinicalTrials.gov and the bibliographies of relevant articles to locate additional publications in September 2016. Three evaluators independently reviewed and selected eligible studies based on predetermined selection criteria.

RESULTS

Of 522 articles meeting our initial criteria, a total of seven open-label, randomised controlled trials involving 548 participants, were included in the final analysis. Vitamin D supplementation in combination with Peg-IFN-α injection and oral RBV significantly increased the rate of viral response for hepatitis C at 24 weeks after treatment in a random-effects meta-analysis (relative risk = 1.30; 95% confidence interval = 1.04-1.62; I² = 75.9%). Also, its significant efficacy was observed in patients with hepatitis C virus genotype 1, which is known to be refractory to antiviral therapy.

CONCLUSIONS

In summary, we observed that additional use of vitamin D has a positive effect on sustained viral response rates of patients with chronic hepatitis C infection. However, we cannot establish the efficacy because of substantial heterogeneity, a small sample size and a low methodological quality.

agr functionality affects clinical outcomes in patients with persistent methicillin-resistant Staphylococcus aureus bacteraemia

Methicillin-resistant Staphylococcus aureus bacteremia (MRSAB) often persists despite appropriate antibiotic therapy. It is unclear what microbiological factors contribute to poor clinical outcomes in persistent MRSAB (pMRSAB). We aimed to identify clinical and microbiological risk factors for in-hospital mortality in pMRSAB. We analysed MRSAB cases prospectively collected between 2009 and 2016 at 11 hospitals in Korea, defining cases of pMRSAB as MRSAB lasting ≥5 days despite administration of effective antibiotics. The first blood isolates from the pMRSAB cases were tested for staphylococcal cassette chromosome mec type, staphylococcal protein A type, accessary gene regulator (agr) type, genes for Panton-Valentine leukocidin and phenol-soluble modulin-mec, vancomycin minimum inhibitory concentration, vancomycin heteroresistance, and agr functionality. We also collected clinical information for each case. Of 960 MRSAB cases, 152 pMRSAB were finally eligible. Univariable analysis revealed that in-hospital mortality was significantly associated with Charlson's comorbidity-weighted index (CCWI) score, Pitt bacteremia score, sequential organ failure assessment score, presentation with septic shock, pneumonia, agr dysfunction, and vancomycin heteroresistance. Bone and joint infections were negatively associated with in-hospital mortality. Multivariable analysis revealed the following independent risk factors for in-hospital mortality: CCWI score [adjusted odds ratio (aOR), per one point, 1.25; 95% confidence interval (CI), 1.08-1.44; P = 0.003), Pitt bacteremia score (aOR, per one point, 1.33; 95% CI, 1.09-1.62; P = 0.005), non-eradicated foci of infection (aOR, 3.12; 95% CI, 1.18-8.27; P = 0.022), and agr dysfunction (aOR, 2.48; 95% CI, 1.12-5.47; P = 0.025). agr dysfunction is an independent risk factor for in-hospital mortality in pMRSAB.

Validation of the Korean National Healthcare-associated Infections Surveillance System (KONIS): an intensive care unit module report

BACKGROUND

National surveillance data should be validated to identify methodological problems within the surveillance programme and data quality issues.

AIM

To test the validity of healthcare-associated infection (HAI) rate data from the Korean National Healthcare-associated Infections Surveillance System (KONIS).

METHODS

Records from intensive care units of 12 (14.8%) of 81 participating hospitals for January-March 2014 were examined. The validation team reviewed 406 medical records of 110 patients with 114 reported HAIs - including 34 urinary tract infections (UTIs), 57 bloodstream infections (BSIs) and 23 cases of pneumonia (PNEU) - and 296 patients with no reported HAIs during one-day visits conducted in August and September 2014. The reviewers' diagnosis of HAI was regarded as the reference standard; in ambiguous cases, the KONIS Steering Committee confirmed the diagnosis of HAI.

FINDINGS

Sensitivity values for UTIs, BSIs and PNEU were 85.3%, 74.0% and 66.7%, and specificity values were 98.7%, 99.1% and 98.7%, respectively. Positive predictive values were 85.3%, 94.7% and 78.3%, and negative predictive values were 98.7%, 94.6% and 97.7%, respectively. Sensitivity for PNEU was lower than that for UTIs and BSIs. The hospitals participating in KONIS infrequently reported conditions that were not HAIs. Sensitivity for BSIs was lower in this study than in KONIS validation studies conducted in 2008 and 2010.

CONCLUSIONS

KONIS data are generally reliable; however, sensitivity for BSIs exhibited a decrease. This study shows the need for ongoing validation and continuous training of surveillance personnel to maintain the accuracy of surveillance data.

Characteristics of cefazolin inoculum effect-positive methicillin-susceptible staphylococcus aureus infection in a multicentre bacteraemia cohort

Cefazolin treatment failure has been observed in high-inoculum infections caused by methicillin-susceptible Staphylococcus aureus (MSSA) with a cefazolin inoculum effect (CIE). However, data on the characteristics and risk factors for the acquisition of CIE-positive MSSA infection are scarce. CIE positivity was measured as an MIC ≥ 16 μg/ml with a high inoculum (∼5 × 10⁷ CFU/ml). The blaZ gene type was assessed through sequence analysis. The clinical characteristics and risk factors for the acquisition of CIE-positive MSSA infection were assessed. The association between the antimicrobial susceptibility profile and CIE positivity was evaluated. A total of 303 MSSA bacteraemia cases and their corresponding isolates were collected from ten hospitals: 61 (20.1 %) isolates showed a positive CIE; 254 (83.8 %) were positive for the blaZ gene. No significant association was found between CIE positivity and the site of infection. Metastatic cancer (aOR 2.86, 95 % CI, 1.10-7.48) and recent (≤1 month) close contact with a chronically ill patient (aOR 4.69, 95 % CI, 1.76-12.50) were identified as significant risk factors for CIE-positive MSSA infection through multivariate analyses. Resistances to clindamycin (OR 3.55, 95 % CI, 1.62-7.80) and erythromycin (OR 5.00, 95 % CI, 2.50-9.99) were associated with CIE positivity, presenting high specificity (92.9 %) and a negative predictive value (82.3 %). CIE-positive MSSA constituted approximately one-fifth of MSSA bacteraemia cases. Although CIE positivity was not clinically discernible, CIE positivity was associated with clindamycin or erythromycin susceptibility. Therefore, our findings suggest that cefazolin can be used in the treatment of high-inoculum MSSA infection if the isolates are susceptible to clindamycin or erythromycin.

What Is the Role of Developmental Disability in Patient Selection for Pediatric Solid Organ Transplantation?

The National Organ Transplant Act stipulates that deceased donor organs should be justly and wisely allocated based on sound medical criteria. Allocation schemes are consistent across the country, and specific policies are publicly vetted. Patient selection criteria are largely in the hands of individual organ transplant programs, and consistent standards are less evident. This has been particularly apparent for patients with developmental disabilities (DDs). In response to concerns regarding the fairness of transplant evaluations for patients with DDs, we developed a transplant centerwide policy using a multidisciplinary, community-based approach. This publication details the particular policy of our center. All patients should receive individualized assessments using consistent standards; disability should be neither a relative nor an absolute contraindication to transplantation. External review can increase trust in the selection process. Patients in persistent vegetative states should not be listed for transplantation.

Five-year decreased incidence of surgical site infections following gastrectomy and prosthetic joint replacement surgery through active surveillance by the Korean Nosocomial Infection Surveillance System

BACKGROUND

Surveillance of healthcare-associated infection has been associated with a reduction in surgical site infection (SSI).

AIM

To evaluate the Korean Nosocomial Infection Surveillance System (KONIS) in order to assess its effects on SSI since it was introduced.

METHODS

SSI data after gastrectomy, total hip arthroplasty (THA), and total knee arthroplasty (TKA) between 2008 and 2012 were analysed. The pooled incidence of SSI was calculated for each year; the same analyses were also conducted from hospitals that had participated in KONIS for at least three consecutive years. Standardized SSI rates for each year were calculated by adjusting for SSI risk factors. SSI trends were analysed using the Cochran-Armitage test.

FINDINGS

The SSI rate following gastrectomy was 3.12% (522/16,918). There was a significant trend of decreased crude SSI rates over five years. This trend was also evident in analysis of hospitals that had participated for more than three years. The SSI rate for THA was 2.05% (157/7656), which decreased significantly from 2008 to 2012. The risk factors for SSI after THA included the National Nosocomial Infections Surveillance risk index, trauma, reoperation, and age (60-69 years). The SSI rate for TKA was 1.90% (152/7648), which also decreased significantly during a period of five years. However, the risk-adjusted analysis of SSI did not show a significant decrease for all surgical procedures.

CONCLUSION

The SSI incidence of gastrectomy and prosthetic joint replacement declined over five years as a result of active surveillance by KONIS.

Trends in the distribution and antimicrobial susceptibility of causative pathogens of device-associated infection in Korean intensive care units from 2006 to 2013: results from the Korean Nosocomial Infections Surveillance System (KONIS)

BACKGROUND

For all countries, information on pathogens causing healthcare-associated infections is important in order to develop proper strategies for preventing and treating nosocomial infections.

AIM

To assess the change in frequencies and antimicrobial resistance of pathogens causing device-associated infections (DAIs) in intensive care units (ICUs) in South Korea between July 2006 and June 2014.

METHODS

Data from the Korean Nosocomial Infections Surveillance System (KONIS) were analysed, including three major DAI types in ICUs.

FINDINGS

The frequency of Gram-negative bacteria gradually increased for central line-associated bloodstream infection (CLABSI) and ventilator-associated pneumonia (VAP) (from 24.6% to 32.6% and from 52.8% to 73.5%, respectively). By contrast, the frequency of Gram-positive bacteria decreased from 58.6% to 49.2% for CLABSI, and from 44.3% to 23.8% for VAP (P < 0.001). Staphylococcus aureus was the most frequent causative pathogen in CLABSI throughout the surveillance period, but for VAP was replaced as the most frequent pathogen by Acinetobacter baumannii as of 2010. Candida albicans was the most frequent pathogen for catheter-associated urinary tract infection. The meticillin resistance rate in S. aureus decreased from 95% to 90.2% (P < 0.001); amikacin resistance in Klebsiella pneumoniae and Escherichia coli decreased from 43.8% to 14.7% and from 15.0% to 1.8%, respectively (P < 0.001); imipenem resistance in A. baumannii increased from 52.9% to 89.8% (P < 0.001).

CONCLUSION

The proportion of Gram-negative bacteria as nosocomial pathogens for CLABSI and VAP has increased. The prevalence of A. baumannii causing DAIs in Korean ICUs has increased rapidly, as has the rate of carbapenem resistance in these bacteria.

Which tissues are best for microbiological diagnosis in patients with pyogenic vertebral osteomyelitis undergoing needle biopsy?

Identification of the causative microorganism is important in the management of pyogenic vertebral osteomyelitis (PVO). The aim of this study was to investigate whether culture positive rates differ between needle biopsy sites in patients with PVO, and which tissues are best for microbiological diagnosis. Between January 2005 and December 2013, we conducted a retrospective cohort study of PVO patients who had soft-tissue abscesses (paraspinal or psoas abscesses) and who received needle biopsy for microbiological diagnosis. Needle biopsy sites were classified into two anatomical categories: vertebral bodies, or soft tissues (intervertebral discs, paraspinal abscesses, or psoas abscesses). A generalized estimating equation model was developed to identify factors associated with tissue-culture positivity. During the study period a total of 136 tissues were obtained by needle biopsy from 128 PVO patients with soft-tissue abscesses. The culture positive rates of vertebral bodies and soft tissues were 39.7% (29/73), and 63.5% (40/63), respectively (p < 0.05). In a multivariate analysis, male gender (adjusted odds ratio (aOR) 2.24, 95% CI 1.00-5.02), higher C-reactive protein (aOR 1.07, 95% CI 1.01-1.15), positive blood culture (aOR 2.57, 95% CI 1.01-6.59), and soft tissues as biopsy site compared with vertebral bodies (aOR 2.28, 95% CI 1.08-4.78) were independent factors associated with tissue culture positivity. Soft tissues were the best sites for microbiological diagnosis in PVO patients undergoing needle biopsy.

Effects of Palm Kernel Expellers on Productive Performance, Nutrient Digestibility, and White Blood Cells of Lactating Sows

This experiment was conducted to investigate the effects of palm kernel expellers on productive performance, nutrient digestibility, and changes in white blood cells (WBC) of lactating sows. A total of 14 sows (200±12 kg of average body weight [BW]; 2.5 of average parity) were used and moved from gestation room to farrowing room on d 109 of gestation. Sows were randomly assigned to 2 dietary treatments in a completely randomized design. The treatments were a diet based on corn and soybean meal (CON) and CON added with 20% of palm kernel expellers (PKE). Sows were fed the treatments for 28 days (weaning) after farrowing. Blood was collected from each sow and 4 randomly selected piglets from each sow before farrowing or on d 3, 7, or 14 of lactation. Sows were fed respective treatments containing 0.2% chromic oxide from d 15 to 21 of lactation. Fecal samples were collected daily for the last 3 days after the 4-d adjustment period. Measurements were performances and WBC changes of sows and litter, nutrient digestibility of sows, and daily diarrhea of litter. Sows fed PKE had greater average daily feed intake (7.38 vs 7.10 kg/d; p<0.05) and lost less BW (−6.85 vs −8.54 kg; p<0.05) and backfat depth (−0.42 vs −0.71 mm; p<0.05) than those fed CON. However, there were no differences on digestibility of dry matter, nitrogen, and energy and weaning to estrus interval of sows fed either CON or PKE. Piglets from sows fed PKE gained more BW (203 vs 181 g/d; p = 0.08) and had less frequency of diarrhea (6.80 vs 8.56%; p = 0.07) than those from sows fed CON. On the other hand, no difference was found on preweaning mortality of piglets from sows fed either CON or PKE. Sows fed PKE had lower number of WBC (9.57 vs 11.82 ×10³/μL; p = 0.09) before farrowing than those fed CON, but no difference on d 3 and 7. Similarly, piglets from sows fed PKE had also lower number of WBC (7.86 vs 9.80 ×10³/μL; p<0.05) on d 14 of lactation than those from sows fed CON, but no difference on d 3 and 7. In conclusion, addition of 20% palm kernel expellers to lactation diet based on corn and soybean meal had no negative effects on productive performance, nutrient digestibility, and WBC changes of lactating sows.

Effects of Palm Kernel Expellers on Growth Performance, Nutrient Digestibility, and Blood Profiles of Weaned Pigs

This experiment was conducted to investigate the effects of palm kernel expellers on growth performance, nutrient digestibility, and blood profiles of weaned pigs. A total of 88 weaned pigs (6.94±0.76 kg body weight [BW]; 28 d old) were randomly allotted to 2 dietary treatments (4 pigs/pen; 11 replicates/treatment) in a randomized complete block design (sex as a block). The dietary treatments were a typical nursery diet based on corn and soybean meal (CON) and CON added with 20% of palm kernel expellers (PKE). Pigs were fed for 6 wk using a 3-phase feeding program with declining diet complexity and with phases of 1, 2, and 3 wk, respectively. Blood was collected from randomly selected 2 pigs in each pen before weaning and on d 7 after weaning. Pigs were fed respective dietary treatments containing 0.2% chromic oxide from d 29 to 35 after weaning. Fecal samples were collected from randomly selected 2 pigs in each pen daily for the last 3 days after the 4-d adjustment period. Measurements were growth performances, digestibility of dry matter, nitrogen and energy, white and red blood cell counts, packed cell volume, and incidence of diarrhea. The PKE increased average daily gain (ADG) (246 vs 215 g/d; p = 0.06) and average daily feed intake (ADFI) (470 vs 343 g/d; p<0.05) and decreased gain-to-feed ratio (G:F) (0.522 vs 0.628 g/g; p<0.05) during phase 2 compared with CON, but did not affect growth performance during phase 1 and 3. During overall experimental period, PKE increased ADG (383 vs 362 g/d; p = 0.05) and ADFI (549 vs 496 g/d; p<0.05) compared with CON, but did not affect G:F. However, no differences were found on digestibility of dry matter, nitrogen, and energy between CON and PKE. The PKE reduced frequency of diarrhea (15% vs 25%; p = 0.08) for the first 2 wk after weaning compared with CON. Similarly, PKE decreased white blood cells (8.19 vs 9.56×10(3)/μL; p = 0.07), red blood cells (2.92 vs 3.25×10(6)/μL; p = 0.09), and packed cell volume (11.1% vs 12.6%; p = 0.06) on d 7 after weaning compared with CON. In conclusion, addition of 20% palm kernel expellers to nursery diet based on corn and soybean meal had no negative effects on growth performance, nutrient digestibility, and blood profiles of weaned pigs.

Trends in the incidence rate of device-associated infections in intensive care units after the establishment of the Korean Nosocomial Infections Surveillance System

BACKGROUND

The effectiveness of continuous nationwide surveillance on healthcare-associated infections should be investigated in each country.

AIM

To assess the rate of device-associated infections (DAIs) in intensive care units (ICUs) since the establishment of the Korean Nosocomial Infections Surveillance System (KONIS).

METHODS

Nationwide data were obtained on the incidence rate of DAI in ICUs reported to KONIS by all participating hospitals. The three major DAIs were studied: ventilator-associated pneumonia (VAP), central line-associated bloodstream infection (CABSI), and catheter-associated urinary tract infection (CAUTI). The pooled and year-wise incidence rates (cases per 1000 device-days) of these DAIs were determined for the period 2006 and 2012. In addition, data from institutions that had participated in KONIS for at least three consecutive years were analysed separately.

FINDINGS

The number of ICUs participating in KONIS gradually increased from 76 in 2006 to 162 in 2012. Between 2006 and 2012, the incidence rate per 1000 device-days for VAP decreased significantly from 3.48 to 1.64 (F = 11, P < 0.01), for CAUTI the rate decreased non-significantly from 1.85 to 1.26 (F = 2.02, P = 0.07), and for CABSI the rate also decreased non-significantly from 3.4 to 2.57 (F = 1.73, P = 0.12). In the 132 ICUs that had participated in KONIS for at least three consecutive years, the VAP rate significantly decreased from the first year to third year (F = 20.57, P < 0.01), but the rates of CAUTI (F = 1.06, P = 0.35) and CABSI (F = 1.39, P = 0.25) did not change significantly.

CONCLUSION

The decreased incidence rate of VAP in ICUs in Korea might be associated with the continuous prospective surveillance provided by KONIS.

Association of obesity with serum leptin, adiponectin, and serotonin and gut microflora in beagle dogs

Background

Serotonin (5‐hydroxytryptamine, 5HT) is involved in hypothalamic regulation of energy consumption. Also, the gut microbiome can influence neuronal signaling to the brain through vagal afferent neurons. Therefore, serotonin concentrations in the central nervous system and the composition of the microbiota can be related to obesity.

Objective

To examine adipokine, and, serotonin concentrations, and the gut microbiota in lean dogs and dogs with experimentally induced obesity.

Animals

Fourteen healthy Beagle dogs were used in this study.

Methods

Seven Beagle dogs in the obese group were fed commercial food ad libitum, over a period of 6 months to increase their weight and seven Beagle dogs in lean group were fed a restricted amount of the same diet to maintain optimal body condition over a period of 6 months. Peripheral leptin, adiponectin, 5HT, and cerebrospinal fluid (CSF‐5HT) levels were measured by ELISA. Fecal samples were collected in lean and obese groups 6 months after obesity was induced. Targeted pyrosequencing of the 16S rRNA gene was performed using a Genome Sequencer FLX plus system.

Results

Leptin concentrations were higher in the obese group (1.98 ± 1.00) compared to those of the lean group (1.12 ± 0.07, P = .025). Adiponectin and 5‐hydroytryptamine of cerebrospinal fluid (CSF‐5HT) concentrations were higher in the lean group (27.1 ± 7.28) than in the obese group (14.4 ± 5.40, P = .018). Analysis of the microbiome revealed that the diversity of the microbial community was lower in the obese group. Microbes from the phylum Firmicutes (85%) were predominant group in the gut microbiota of lean dogs. However, bacteria from the phylum Proteobacteria (76%) were the predominant group in the gut microbiota of dogs in the obese group.

Conclusions and Clinical Importance

Decreased 5HT levels in obese group might increase the risk of obesity because of increased appetite. Microflora enriched with gram‐negative might be related with chronic inflammation status in obese dogs.

Outbreak among healthy newborns due to a new variant of USA300-related meticillin-resistant Staphylococcus aureus

BACKGROUND

The prevalence of community-associated meticillin-resistant Staphylococcus aureus (CA-MRSA) is increasing throughout the world and is an important cause of skin and soft tissue infection (SSTI) in children and neonates.

AIM

To describe the successful control of an outbreak caused by a new strain of CA-MRSA in a newborn nursery.

METHODS

The investigation of the outbreak in July 2012 is reported with the control measures taken. Molecular typing of the MRSA isolates was performed.

FINDINGS

An outbreak of SSTI caused by CA-MRSA occurred in a newborn nursery. Six neonates were infected in a one-month period [infection rate: 8.5% (6/71)]. A new variant of CA-MRSA was responsible, which was characterized as USA300-related, Panton-Valentine Leucocidin (PVL) positive, arginine catabolic mobile element (ACME) negative, sequence type 8 (ST8), staphylococcal cassette chromosome mec (SCCmec) type IVa, agr type I and spa type t008. The outbreak among term neonates followed a rapid transmission pattern and was successfully controlled by implementing various outbreak control measures, including universal chlorhexidine bathing.

CONCLUSION

This is the first report of a hospital outbreak caused by a USA300-related CA-MRSA clone in Korea. Early recognition and reinforcement of infection control measures are important in decreasing transmission of CA-MRSA in a hospital setting.

Partial esophageal transplantation is possible as part of a multivisceral graft

We report a case of a 9-year-old female with inflammatory myofibroblastic tumor (IMT), which involved the upper retroperitoneum, visceral vessels, stomach and distal esophagus. Complete resection of the tumor required a multivisceral (MV) transplant. Due to tumor involvement, resection of the distal third of recipient esophagus was necessary. Gastrointestinal continuity was subsequently established via esophagoesophagostomy to donor esophagus en bloc with a standard MV graft. After 1.9 years of follow-up, the patient has no symptoms of dysphagia or reflux. This case illustrates the feasibility of including the distal donor esophagus as part of an MV graft.

A macrophage-specific synthetic promoter for therapeutic application of adiponectin

Foam cell formation from macrophage is a major cause of atherosclerosis. An efficient macrophage-specific promoter is required for the targeting to macrophages. In this study, we develop a macrophage-specific synthetic promoter for the therapeutic application of adiponectin (APN), an antiatherogenic gene. Synthetic promoter-146 (SP146), registered on the NCBI website (http://www.ncbi.nlm.nih.gov/nuccore/DQ107383), was tested for promoter activities in two non-macrophage cell lines (293 T, HeLa) and a macrophage cell line (RAW264.7, bone marrow-derived macrophages). To enforce macrophage specificity, partial elements of p47(phox) including the PU.1 site with various lengths (-C1, -C2 and -C3) were inserted next to the synthetic promoters. SP146-C1 showed the highest specificity and efficacy in RAW264.7 cells and was selected for development of an APN-carrying macrophage-specific promoter. Green fluorescent protein (GFP)- or APN-expressing lentivirus under SP146-C1 (Lenti-SP-GFP or Lenti-SP-APN, respectively) showed the highest expression efficacy in RAW264.7 cells compared with the non-macrophage cell lines. APN overexpression in RAW264.7 cells successfully inhibited intracellular lipid accumulation, and atherosclerotic lesions and lipid accumulation were significantly reduced by Lenti-SP-APN in ApoE-/- atherosclerosis mice. In conclusion, the synthetic promoter SP146-C1, combined with a p47(phox) promoter element, was successfully developed to target macrophage, and macrophage-specific introduction of APN under SP146-C1 was shown to ameliorate the atherosclerotic pathology.

Reno-portal anastomosis as an approach to pediatric kidney transplantation in the setting of inferior vena cava thrombosis

In pediatric renal transplantation in the setting of IVC thrombosis, the retrohepatic IVC or gonadal veins are often used for outflow. However, if use of systemic venous outflow is unsuccessful, options become limited. We report the use of the portal vein for venous outflow in kidney retransplantation in the setting of IVC thrombosis. The patient is a 19-month-old male who developed end-stage renal failure at seven months of age secondary to hypotension after spontaneous rupture of an accessory renal vein. The IVC was occluded during emergent laparotomy, and the patient developed extensive IVC thrombosis. The first two transplant attempts used the retrohepatic IVC for venous outflow. Despite good initial flow, in both instances the renal vein thrombosed on post-operative day 1. In an unsuccessful salvage attempt of the second transplant, a reno-portal anastomosis was performed. With few options for vascular access, a third transplant was attempted. The reno-portal stump from the second transplant was used for outflow. The patient recovered well from his third transplant (creatinine 0.6 mg/dL 35 months post-surgery), demonstrating that the portal vein can be used for outflow in cases of extensive IVC thrombosis.

Aorto-mesenteric and renal allograft transplant: a novel treatment for midaortic syndrome

Midaortic syndrome (MAS) is a rare condition characterized by stenosis of the aorta and often involving renal and visceral arteries. Current therapies include medical management of associated hypertension, and interventional procedures such as angioplasty or surgical bypass. We report a 2-year-old female with severe MAS who was initially treated with angioplasty and stents in both her aorta and superior mesenteric artery (SMA). Due to the presence of long segment stenoses, her renal arteries were not amenable to surgical reconstruction and she rapidly progressed to Stage V chronic kidney disease. The patient underwent bilateral nephrectomy and renal transplantation using a donor thoracoabdominal aorta allograft to provide inflow for the kidney as well as to bypass the nearly occluded aorta. The donor SMA was used to bypass the native SMA stenosis. Postoperatively, the patient had normalization of four limb blood pressures. She weaned from five anti-hypertensive agents to monotherapy with excellent renal function. This is the first reported case of thoracoabdominal aortic bypass using allograft aorta to address MAS. This approach allowed for successful kidney transplantation with revascularization of the mesenteric, and distal aortic circulation using allograft conduit that will grow with the child, obviating the need for repeated interventional or surgical procedures.

Multivisceral transplantation using a 2.9 kg neonatal donor

Prematurity and very low birthweight have often been considered relative contraindications to neonatal organ donation. Organ procurement from neonatal donors is further complicated by unclear guidelines regarding neonatal brain death. We report a successful case of multivisceral transplantation using a graft from a 10-day-old, 2.9 kg, neonatal donor born at 36 6/7 wk in a 3.2 kg, three month old with intestinal and liver failure secondary to midgut volvulus. There was immediate liver graft function with correction of recipient coagulopathy, but delayed normalization of laboratory values and delayed return of bowel function. At six-yr post-transplant follow-up, the patient has normal intestine and liver function. Her last histologically confirmed rejection episode was 30 months prior to last follow-up. This case suggests that multivisceral grafts from very young or small neonatal donors may be transplanted successfully in selected cases. We propose a re-examination of the brain death guidelines for premature and young infants to potentially increase the availability of organs for infant recipients.

Effects of 12 weeks of aerobic exercise on body composition and vascular compliance in obese boys

AIM

This study tested the hypothesis that 12 weeks of air board exercise would enhance cardiorespiratory fitness and vascular compliance and reduce % body fat in obese Korean boys.

METHODS

Twenty-two obese boys (>30% body fat) were studied. They were divided into 2 groups- an aerobic exercise group (N.=12), which trained 3 days/week, 50 min/day for 12 weeks, and a control group (N.=10). Control subjects only performed activities involved in their physical education classes. Body composition, cardiovascular fitness (20 m multistage endurance test performance) and vascular compliance were assessed before and after the completion of exercise training.

RESULTS

The % changes in body fat (-4.6±0.9 vs. -1.5±1.0%), fat mass (-5.4±1.5 vs. -0.1±1.6%) and performance on the cardiovascular fitness test (14.3±2.5 vs. 3.7±1.6%) were greater in the exercise group than in the controls Compared to controls, % increases in vascular compliance were greater in the arms and legs of the exercise group (left arm: 2.8±0.5 vs. 2.0±2.9%; left leg: 2.6±1.2 vs. -0.5±2.0%; right arm: 2.9±0.9 vs. 0.3±2.9%; right leg: 4.8±1.8 vs. 1.5±2.0%).

CONCLUSION

Results suggest that exercise training can reduce % body fat and enhance vascular compliance in obese male adolescents; changes that may reduce the risk for later development of cardiovascular disease.

The critical role of catalase in prooxidant and antioxidant function of p53

The tumor suppressor p53 is an important regulator of intracellular reactive oxygen species (ROS) levels, although downstream mediators of p53 remain to be elucidated. Here, we show that p53 and its downstream targets, p53-inducible ribonucleotide reductase (p53R2) and p53-inducible gene 3 (PIG3), physically and functionally interact with catalase for efficient regulation of intracellular ROS, depending on stress intensity. Under physiological conditions, the antioxidant functions of p53 are mediated by p53R2, which maintains increased catalase activity and thereby protects against endogenous ROS. After genotoxic stress, high levels of p53 and PIG3 cooperate to inhibit catalase activity, leading to a shift in the oxidant/antioxidant balance toward an oxidative status, which could augment apoptotic cell death. These results highlight the essential role of catalase in p53-mediated ROS regulation and suggest that the p53/p53R2-catalase and p53/PIG3-catalase pathways are critically involved in intracellular ROS regulation under physiological conditions and during the response to DNA damage, respectively.

Comparative faecal microbiota of dogs with and without calcium oxalate stones

AIMS

The absence of enteric oxalate-metabolizing bacterial species (OMBS) increases the likelihood of calcium oxalate (CaOx) urolithiasis in humans and dogs. The goal of this study was to compare the gut microbiota of healthy dogs and CaOx stone formed dogs (CaOx-dogs), especially with respect to OMBS.

METHODS AND RESULTS

Faecal samples from healthy and CaOx-dogs were obtained to analyse the hindgut microbiota by sequencing the V3 region of bacterial 16S rDNA. In total, 1223 operational taxonomic units (OTUs) were identified at 97% identity. Only 38% of these OTUs were shared by both groups. Significant differences in the relative abundance of 152 OTUs and 36 genera were observed between the two groups of dogs.

CONCLUSIONS

The faecal microbiota of healthy dogs is distinct from that of CaOx-dogs, indicating that the microbiota is altered in CaOx-dogs.

SIGNIFICANCE AND IMPACT OF THE STUDY

This is the first study that has compared the gut microbial diversity in healthy and CaOx-dogs. Results of this study indicate the future need for functional and comparative analyses of the total array of oxalate-metabolizing genes between healthy and CaOx stone formers, rather than focusing on specific bacterial species, to understand the critical role of OMBS in CaOx urolithiasis.

Reduced size liver transplantation from a donor supported by a Berlin Heart

Patients on cardiac assist devices are often considered to be high-risk solid organ donors. We report the first case of a reduced size liver transplant performed using the left lateral segment of a pediatric donor whose cardiac function was supported by a Berlin Heart. The recipient was a 22-day-old boy with neonatal hemochromatosis who developed fulminant liver failure shortly after birth. The transplant was complicated by mild delayed graft function, which required delayed biliary reconstruction and abdominal wall closure, as well as a bile leak. However, the graft function improved quickly over the first week and the patient was discharged home with normal liver function 8 weeks after transplant. The presence of a cardiac assist device should not be considered an absolute contraindication for abdominal organ donation. Normal organ procurement procedures may require alteration due to the unusual technical obstacles that are encountered when the donor has a cardiac assist device.

Effect of active smoking on asthma symptoms, pulmonary function, and BHR in adolescents

BACKGROUND

Active smoking is known to increase asthma symptoms and bronchial hyper-responsiveness (BHR) while decreasing pulmonary function in adults, but few studies have addressed these issues in adolescents.

METHODS

We conducted a cross-sectional survey involving questionnaires and assessment of urinary cotinine levels among 1,492 adolescents from three urban areas of South Korea. Current smoking was defined as having smoked more than 1 day in the prior 30 days or having urine cotinine levels >or=100 ng/ml. Spirometry, skin tests, and methacholine challenge tests were performed on adolescents in Seoul (n = 724).

RESULTS

The prevalence of current smoking was 8.2% in boys and 2.4% in girls. Reports of wheeze and exercise-induced wheeze in the previous 12 months were more frequent in smokers than nonsmokers (15.2% vs. 8.5%, P = 0.024, and 20.4% vs. 10.7%, P = 0.004, respectively). In multiple logistic regression analysis, current smoking was found to be a significant risk factor for having wheezed in previous 12 months (OR = 4.5, 95% CI 1.5-13.2) and having exercise-induced wheezing in previous 12 months (OR = 8.7, 95% CI, 3.7-20.9). The subgroup analysis revealed that the FEV(1)/FVC was lower in smokers than nonsmokers (mean +/- SD, 105.1 +/- 8.6% vs. 107.8 +/- 7.8%, P = 0.019). In contrast, there was no significant difference in BHR. The effect of smoking on asthma symptoms were more pronounced in non-atopic compared with atopic adolescents.

CONCLUSION

Current smoking was significantly associated with symptoms of asthma, such as having recent wheezing and recent exercise-induced wheezing, especially for non-atopics, in Korean adolescent population. Current smoking was further associated with lower pulmonary function, but not BHR.

Ribonucleotide reductase small subunit p53R2 suppresses MEK-ERK activity by binding to ERK kinase 2

The p53-dependent RR small subunit (p53R2) protein, a newly identified member of the ribonucleotide reductase family, plays a key role in the p53-dependent cellular response to DNA. Several recent studies have suggested that p53R2 also plays an important role in suppressing the invasive potential of human cancer cells. However, the cellular mechanism that regulates invasiveness remains largely unknown. In this study, we show that p53R2 interacts with MEK2 (extracellular signal-regulated kinase (ERK) kinase 2-mitogen-activated protein kinase (MAPK) kinase 2), the molecule immediately upstream of ERK in the Ras-Raf-MAPK signaling cascade. In co-immunoprecipitation and immunofluorescence analyses, we found that p53R2 and MEK2 interact physically in cultured mammalian cells, and that the p53R2 segment comprising amino acids 161-206 is critical for this interaction. Moreover, serum-induced phosphorylation of MEK1/2 and ERK1/2 was greatly augmented in human cancer cells expressing small-interfering RNA against p53R2. On the other hand, phosphorylation of MEK1/2 and ERK1/2 in human cancer cells was markedly attenuated by overexpression of p53R2. Furthermore, MEK2 was required for p53R2 knockdown-induced enhancement of the invasive ability and anchorage-independent growth of human lung cancer H1299 cells. Taken together, these findings show that p53R2 negatively modulates serum-induced MEK-ERK activity and inhibits the MEK-ERK-mediated malignancy potential of human cancer cells.

Retrobulbar optic neuritis and meningoencephalitis following progressive outer retinal necrosis due to CMV in a patient with AIDS

We report on a 34-year-old male patient with AIDS who developed retrobulbar optic neuritis and meningoencephalitis following bilateral progressive outer retinal necrosis (PORN) caused by cytomegalovirus (CMV). This case documents the presumed association of PORN with retrobulbar optic neuritis, and CMV meningoencephalitis in an AIDS patient.

A familial case of pleuropulmonary blastoma

PURPOSE

Pleuropulmonary blastoma (PPB) is a rare intrathoracic neoplasm of early childhood arising in the lung or visceral pleura. Approximately 150 cases have been reported in the literature, with only one previously documented case of PPB in siblings.

PATIENTS AND METHODS

We present the case of two brothers diagnosed with PPB.

RESULTS

A two month-old boy with an abnormal breathing pattern was referred for evaluation of a cystic mass discovered on chest radiograph. Computed tomography (CT) of the chest was performed at our institution which revealed findings compatible with congenital cystic adenomatoid malformation (CCAM) of the right middle and lower lobes. The patient underwent urgent thoracic exploration one week later after developing severe respiratory distress. Histological examination revealed PPB type I (cystic). The patient's 15-month-old brother was presumed to have a CCAM noted radiographically months earlier during an asthma exacerbation. He underwent elective cyst resection and was also found to have type I PPB. The index patient was treated with adjuvant chemotherapy due to the large size of the PPB and intraoperative spillage of cystic fluid during the emergent surgery. In contrast, the brother is being followed without adjuvant chemotherapy, given the much smaller size of the PPB, wide margins of resection, and lack of spillage. Family history included an uncle diagnosed at age 11 with an unusual form of T cell acute lymphoblastic leukemia.

CONCLUSION

Although PPB is known to have a familial association with other neoplasms, this case represents only the second report of PPB occurring in siblings. The importance of thoroughly investigating and resecting pulmonary cystic masses in the pediatric population is highlighted by these cases.

Combined effect of tumour necrosis factor-alpha and interleukin-13 polymorphisms on bronchial hyperresponsiveness in Korean children with asthma

BACKGROUND

TNF-alpha and IL-13, two pivotal pro-inflammatory cytokines, are increased in asthmatic airways and may be linked to asthma susceptibility and/or bronchial hyperresponsiveness (BHR).

OBJECTIVE

We investigated the association between the TNF-alpha-308G/A polymorphism and asthma susceptibility or asthma-related phenotypes in Korean children with asthma, and tested for a combined effect with IL-13 polymorphisms.

METHODS

Asthmatic children (n=719) and non-atopic healthy control children (n=243) were evaluated for asthma phenotypes including total serum IgE and BHR to methacholine. Genotypes were determined by PCR-restriction fragment length polymorphism analysis.

RESULTS

The allele frequency of TNF-alpha-308A in asthmatics (14.1%) was higher than that in control children [8.7%, odds ratio (OR) 1.72, 95% confidence interval (CI) 1.05-2.82]. Significantly lower PC(20) values were found in asthmatic children carrying one or two copies of the TNF-alpha risk allele (-308A) vs. those homozygous for the common allele (P=0.026). Combined analysis revealed that atopic asthmatic children co-inherited the risk alleles of TNF-alpha-308G/A and IL-13 +2044G/A more frequently than control children (aOR 1.91, 95% CI 1.00-3.65), and asthmatic children co-inheriting both risk alleles had significantly lower PC(20) values vs. asthmatic children homozygous for the common alleles (P=0.024).

CONCLUSION

The TNF-alpha promoter polymorphism (-308G/A) may be associated with asthma susceptibility and BHR in Korean children with asthma. In addition, there appears to be a synergistic effect between the TNF-alpha promoter polymorphism and an IL-13 coding region polymorphism in terms of asthma susceptibility and BHR in this population.

TBXA2R gene polymorphism and responsiveness to leukotriene receptor antagonist in children with asthma

BACKGROUND

Thromboxane A2 receptor (TBXA2R) gene polymorphism has been associated with atopy and asthma, but few studies have reported the effect of this gene polymorphism on asthma-related phenotype or responsiveness to leukotriene receptor antagonist (LTRA) in asthmatic children. This study investigated associations between asthma-related phenotypes and TBXA2R polymorphism, and also analysed whether the TBXA2R polymorphism has an effect on the efficacy of the LTRA, montelukast, in asthmatic children with exercise-induced bronchoconstriction (EIB).

METHODS

Asthmatic children (n=695) and control children (n=159) were evaluated for asthma-related phenotypes including total IgE, pulmonary function test, and bronchial hyperresponsiveness to methacholine or exercise. Genotypes were detected by PCR-RFLP. In the montelukast study, exercise challenge was performed before and after an 8-week montelukast treatment.

RESULTS

The TBXA2R polymorphism was not associated with asthma susceptibility and the clinical parameters of asthma. However, asthmatic children with combinations of the TBXA2R+795T>C and +924T>C risk alleles had significantly higher total IgE levels (P=0.01), total eosinophil counts (P<0.01) and lower forced expiratory volume in 1 s (FEV(1)) (P=0.02) and forced expiratory rates at 25-75% of vital capacity (P=0.02) than those carrying the common alleles. When compared with individuals with the common alleles, patients with the TBXA2R+924T>C TT homozygote and TBXA2R+795T>C hetero- or homozygote (CT or CC) had a 3.67-fold poor response to 8-week montelukast treatment with respect to maximum percent fall in FEV(1) after exercise (odds ratio, 3.67; 95% confidence interval, 1.15-11.15).

CONCLUSIONS

A combined effect of TBXA2R+795T>C and +924T>C risk alleles may be linked to IgE production, eosinophilic inflammation, and severity of asthma. In addition, the TBXA2R+795T>C genotype may be a predictive marker of a clinical response to the LTRA in Korean asthmatic children with EIB.

Responsiveness to montelukast is associated with bronchial hyperresponsiveness and total immunoglobulin E but not polymorphisms in the leukotriene C4 synthase and cysteinyl leukotriene receptor 1 genes in Korean children with exercise-induced asthma (EIA)

BACKGROUND

As previous studies have shown that cysteinyl leukotrienes are important mediators in exercise-induced bronchoconstriction (EIB), and leukotriene receptor antagonists (LTRAs) such as montelukast have been shown to improve post-exercise bronchoconstrictor responses, we herein investigated whether clinical responsiveness to montelukast was associated with polymorphisms in the genes encoding leukotriene C4 synthase (LTC4S) and cysteinyl leukotriene receptor 1 (CysLTR1) and/or clinical parameters in Korean asthmatic children with EIB.

METHODS

The study population consisted of 100 asthmatic children with EIB. The individuals studied were given exercise challenge tests before and after receiving montelukast (5 mg/day) for 8 weeks. Responders were defined as children showing>10% post-treatment improvement in forced expiratory volume in 1 s (FEV1). The LTC4S A(-444)C and CysLTR1 T(+927)C polymorphisms were genotyped by PCR-restriction fragment length polymorphism analysis.

RESULTS

Of 100 enrolled children, 68 were classified as responders and 32 were classified as non-responders. No significant association was observed between montelukast responsiveness and LTC4S or CysLTR1 genotype, either alone or in combination. In contrast, montelukast-induced improvement in FEV(1) after exercise was correlated with higher pre-treatment PC20 (methacholine) values (r=0.210, P=0.036) and lower total IgE levels (r=-0.216, P=0.031).

CONCLUSIONS

The LTC4S A(-444)C and CysLTR1 T(+927)C genotypes do not appear to be useful for predicting clinical responsiveness to montelukast, whereas bronchial hyperresponsiveness and total IgE appear to predict the degree of montelukast responsiveness in Korean asthmatic children with EIB.

The persistence of humoral and cellular immunities more than three decades after smallpox vaccination

This study assessed the persistence of humoral (neutralising antibody titre to vaccinia virus) and cellular (immediate vaccinia-specific interferon (IFN)-gamma-producing T-cell) immunities to smallpox in a Korean population. Individuals who were vaccinated 25-60 years previously had higher neutralising antibody titres (geometric mean titre (GMT) 13.7; 95% CI 11.0-17.2) than vaccinia-naive individuals (GMT 6.7; 95% CI 5.5-8.0; p <0.001). However, there was no significant difference in cellular immunity between individuals vaccinated previously and vaccinia-naive individuals, and only 15% of the individuals vaccinated previously displayed an immediate IFN-gamma-producing effector-memory response in ELISPOT assays.