CT and MR for bone mineral density and trabecular bone score assessment in osteoporosis evaluation.

Dual energy X-ray absorptiometry (DXA) is widely used modality for measuring bone mineral density (BMD). DXA is used to measure the quantitative areal BMD of bone, but has the disadvantage of not reflecting the bone architecture. To compensate for this disadvantage, trabecular bone score (TBS), a qualitative parameter of trabecular microarchitecture, is used. Meanwhile, there have been recent attempts to diagnose osteoporosis using the Hounsfield unit (HU) from CT and MR-based proton density fat fraction (PDFF) measurements. In our study, we aimed to find out the correlation between HU/PDFF and BMD/TBS, and whether osteoporosis can be diagnosed through HU/PDFF. Our study revealed that the HU value showed a moderate to good positive correlation with BMD and TBS. PDFF showed a fair negative correlation with BMD and TBS. In diagnosing osteopenia and osteoporosis, the HU value showed good performance, whereas the PDFF showed fair performance. In conclusion, both HU values and PDFF can play a role in predicting BMD and TBS. Both HU values and PDFF can be used to predict osteoporosis; further, CT is expected to show better results.

Population Pharmacokinetics and Monte Carlo Simulation of Cefepime in Critically Ill Patients with Hospital-Acquired/Ventilator-Associated Pneumonia.

BACKGROUND: This study aimed to investigate the population pharmacokinetics (PK) profile and determine the optimal dosage regimen of cefepime in critically ill adult patients with hospital-acquired pneumonia (HAP) or ventilator-associated pneumonia (VAP). MATERIALS AND METHODS: Population-PK models for cefepime were developed using a nonlinear mixed-effect modeling approach. The percentage of time within 24 h in which the free concentration exceeded the minimum inhibitory concentration (MIC) at a steady state (50%fT>MIC, 100%fT>MIC, and 100%fT>4×MIC) for various combinations of dosage regimens and renal function was explored using Monte Carlo simulation. RESULTS: Twenty-one patients were prospectively enrolled in this study. Cefepime PK was best described using a two-compartment model in which creatinine clearance (CLCR) through Cockcroft-Gault (CG) was a significant covariate for the total clearance of cefepime. The simulation results to determine the optimal cefepime dosing regimen for 50%fT>MIC as treatment target with Cmin <20 mg/L as safety target showed that a dosage regimen of 2 g through intravenous (IV) infusion every 12 h administered over 4 h was optimal at an MIC of 4 mg/L, rather than the currently recommended dosage regimen of 2 g administered through IV infusion every 8 h, in patients with normal renal function (CLCR = 90 - 130 mL/min). For a treatment target of 100%fT>MIC with Cmin <35 mg/L as a safety target, a dosage regimen of 0.75 g administered through continuous infusion over 24 h would be sufficient at an MIC equal to or less than 8 mg/L in patients with renal dysfunction (CLCR = 10 - 30 mL/min). CONCLUSION: Our results suggest that clinicians should consider renal function and potential neurotoxicity when deciding the dosing regimen of cefepime in critically ill patients with HAP or VAP. Therapeutic drug monitoring (TDM) to adjust cefepime trough levels may be useful to improve clinical outcomes and reduce cefepime neurotoxicity.

Prevalence and Factors of Osteoporosis and High Risk of Osteoporotic Fracture in Patients with Ankylosing Spondylitis: A Multicenter Comparative Study of Bone Mineral Density and the Fracture Risk Assessment Tool.

BACKGROUND: We investigated the prevalence of and the factors associated with a high risk of osteoporotic fractures in Korean patients with ankylosing spondylitis (AS). METHODS: This was a multicenter, retrospective study including 219 AS patients from five university hospitals; the control group was selected by matching age and sex with those of the AS patients. The fracture risk was evaluated based on bone mineral density (BMD) measured by dual-energy X-ray absorptiometry and the fracture risk assessment tool (FRAX) with/without BMD. RESULTS: The mean age of the patients was 47.6 years, and 144 (65.8%) patients were men. According to the WHO criteria and FRAX with/without BMD, the candidates for pharmacological treatment were 44 (20.1%), 20 (13.2%), and 23 (15.1%) patients, respectively, significantly more than those in the healthy control group. Among them, the proportion of patients receiving osteoporosis treatment was 39.1-75%. In logistic regression analysis, menopause was an independent factor for the high risk of fracture according to the WHO criteria and FRAX with/without BMD. C-reactive protein level (odds ratio (OR) 3.8 and OR 6) and glucocorticoid use (OR 1.5 and OR 1.7) were associated with a high risk of osteoporotic fracture based on FRAX without BMD and osteoporosis diagnosed according to the WHO criteria. CONCLUSIONS: Our study suggests that both FRAX and WHO criteria may be complementary for treatment decisions to reduce osteoporotic fractures in patients with AS.

Incidence and prevalence of immune thrombocytopenia under the copayment waiver policy for pediatric patients in Korea: Data from the National Health Claims Database.

The purpose of this study was to investigate the epidemiology of immune thrombocytopenia (ITP) under the copayment waiver policy for pediatric patients in Korea. The data were collected from the National Health Insurance Claims Database of Korea. ITP was identified based on the diagnostic code D69.38 from the Korean Standard Classification of Diseases. Patients between one and 18 years old, who had at least one health insurance claim for ITP as a final diagnosis, from 1 January 2016, to 31 December 2017, were analyzed. Prevalent cases were defined as patients who used, at least one time, any medical services coded as D69.38. Incident cases were defined as patients who did not use D69.38 coded medical services during the prior year and were newly registered in 2017. The prevalence and incidence of ITP were 24.53 and 13.39 per 100,000 persons. The peak rates were observed in 1-year-old patients. The gender-specific prevalence of ITP was significantly higher in one-year-old males than females. According to the change-point analysis, we found that the prevalence and incidence diminished rapidly at the ages of four and three, respectively. This Korean population-based epidemiological study of ITP provided meaningful insights into the current epidemiology of ITP and demonstrated the implications of interpreting epidemiologic studies to reflect age categorizing and health care system characteristics.

Prevalence of osteoporosis in patients with systemic lupus erythematosus: A multicenter comparative study of the World Health Organization and fracture risk assessment tool criteria.

OBJECTIVES: Osteoporosis and fracture are known complications of systemic lupus erythematosus (SLE). We assessed the prevalence and risk factors for osteoporosis in patients with SLE. METHODS: A total of 155 female SLE patients were recruited retrospectively in 5 university hospitals. The bone mineral density (BMD) was measured by dual-energy X-ray absorptiometry, and the fracture risk assessment tool (FRAX) for high-risk osteoporotic fractures was calculated with and without BMD. RESULTS: The mean age was 53.7 ± 6.8 years, and osteoporotic fractures were detected in 19/127 (15.0%) patients. The proportion of patients having a high-risk for osteoporotic fractures in the FRAX with and without BMD, and osteoporosis by the World Health Organization (WHO) criteria were 25 (16.1%), 24 (15.5%), and 51 (32.9%), respectively, and 48.0-68.6% of them were receiving treatment. On multivariate logistic analysis, nephritis (odds ratio [OR] 11.35) and cumulative dose of glucocorticoid (OR 1.1) were associated with high-risk by the FRAX with BMD, and low complement levels (OR 4.38), erythrocyte sedimentation rate (ESR) (OR 1.04), and cumulative dose of glucocorticoid (OR 1.05) were associated with osteoporosis by the WHO criteria in patients with SLE. CONCLUSIONS: Among Korean female patients with SLE, the proportion of patients having a high-risk of osteoporotic fractures by the FRAX tool was 15.5%-16.1% and the proportion of patients having osteoporosis by the WHO criteria was 32.9%. In SLE, nephritis, low level of complement, ESR, and cumulative dose of glucocorticoids may contribute to fracture risk.

Home Mechanical Ventilation Use in South Korea Based on National Health Insurance Service Data.

BACKGROUND: In Asian countries, nationwide data on patients undergoing home mechanical ventilation are limited. METHODS: This study investigated the prevalence and primary indications for home mechanical ventilation use in South Korea by using nationwide registry data from the National Health Insurance Service. RESULTS: The study period included a total of 4,785 subjects on home mechanical ventilation (mean ± SD age, 56.0 ± 23.9 y; females, 40.1%). The estimated overall prevalence of home mechanical ventilation use in South Korea was 9.3 per 100,000, with a prevalence of 6.3 per 100,000 among children (ages < 15 y). The most common primary diagnoses were neuromuscular diseases (42.0%) and lung and/or airway diseases (27.7%). The prevalence of lung and/or airway and cerebrovascular diseases as the primary diagnosis increased with age (r = 0.310, P < .001; and r = 0.156, P < .001, respectively). Noninvasive ventilation was used by 37.2% of all the subjects, with the highest prevalence in those with neuromuscular diseases (54.4%) or chest wall diseases (53.4%). Noninvasive ventilation use was lowest among subjects with brain lesions. Home mechanical ventilation was most commonly prescribed by internists (41.3% of cases), followed by rehabilitation and neurology physicians. CONCLUSIONS: These data will aid in planning the optimal health-care system for users of home mechanical ventilation locally and will allow for comparison of home mechanical ventilation use rates among countries.

Combination of whole-spine lateral radiograph and lateral scanogram in the assessment of global sagittal balance.

BACKGROUND CONTEXT: Global balance of human standing is analyzed as the geometric sum of the individual alignments extending from the spinal column to the pelvis, and to the lower limbs. The innovative EOS system has opened new perspectives for the global analysis of whole-body alignment, but its use is very limited because of its high cost. An alternative may be to combine the whole-spine lateral radiograph and the lateral scanogram in the global sagittal analysis of whole-body alignment. PURPOSE: We examined to determine the validity and reliability of a lateral scanogram in the measurement of sacropelvic parameters. STUDY DESIGN/SETTING: A retrospective radiological study was carried out. PATIENT SAMPLE: We randomly selected 100 sets of digital radiographs, both whole-spine radiographs and lower-limb scanograms, from our database. OUTCOME MEASURES: Sacropelvic parameters, including pelvic incidence, sacral slope, and pelvic tilt, were measured on both whole-spine radiographs and lower-limb scanograms by three independent examiners on three separate occasions. METHODS: Agreement regarding the measurements on both image types was calculated to assess the validity of the lateral scanogram for use in whole-body alignment determinations. Intraobserver and interobserver reliabilities among the types of measurements were calculated. RESULTS: The sacropelvic area on the lateral scanogram was not visible in 19 patients (19%). In the remaining 81 patients, the sacropelvic parameters on the lateral scanogram were similar to those on the whole-spine lateral radiograph (Pearson correlation coefficient, 0.764-0.805). Intraobserver and interobserver reproducibilities for both modalities were good to excellent (intraclass correlation coefficient, 0.657-0.984). CONCLUSIONS: Sacropelvic parameter measurements on lateral scanogram were reliable and were similar to those measured on whole-spine lateral radiograph. Thus, global alignment can be evaluated using the lateral scanogram in combination with the whole-spine lateral radiograph.

What factors affect discordance between physicians and patients in the global assessment of disease activity in rheumatoid arthritis?

OBJECTIVE: To identify the level of agreement between patients with rheumatoid arthritis (RA) and physicians in the global assessment of disease activity and to explore factors influencing their discordance. METHODS: A total of 4368 patients with RA were analyzed from the KORean Observational study Network for Arthritis (KORONA) database. Patients were divided into four subgroups according to difference from their physicians in the assessment of disease activity by substracting physician's visual analog scale (VAS) from patient's VAS as follows: positive discordance group I (10 mm ≤ discordance <25 mm), positive discordance group II (≥25 mm), concordance (<|10| mm), and negative discordance (≤ -10mm). Multinomial logistic regression analysis was performed to identify factors associated with discordance. RESULTS: Only 1350 (29.2%) patients were classified in the concordance group. Positive discordance was found in 52.3% of the patients (n = 2425), with 33.7% (n = 1563) showing marked discordance (≥25 mm). The high disease activity (OR =1.41), gastrointestinal (GI) disease (OR =1.28), pain (OR =1.12), fatigue (OR =1.07) were consistently associated with positive discordance. CONCLUSION: More than half of patients with RA thought their disease more severe than their physicians. In addition to high disease activity, pain, fatigue, and sleep disturbance or GI disease were associated with the discordance between physicians and patients with RA.

Mapping health assessment questionnaire disability index (HAQ-DI) score, pain visual analog scale (VAS), and disease activity score in 28 joints (DAS28) onto the EuroQol-5D (EQ-5D) utility score with the KORean Observational study Network for Arthritis (KORONA) registry data.

The aim of this study was to estimate the mapping model for EuroQol-5D (EQ-5D) utility values using the health assessment questionnaire disability index (HAQ-DI), pain visual analog scale (VAS), and disease activity score in 28 joints (DAS28) in a large, nationwide cohort of rheumatoid arthritis (RA) patients in Korea. The KORean Observational study Network for Arthritis (KORONA) registry data on 3557 patients with RA were used. Data were randomly divided into a modeling set (80 % of the data) and a validation set (20 % of the data). The ordinary least squares (OLS), Tobit, and two-part model methods were employed to construct a model to map to the EQ-5D index. Using a combination of HAQ-DI, pain VAS, and DAS28, four model versions were examined. To evaluate the predictive accuracy of the models, the root-mean-square error (RMSE) and mean absolute error (MAE) were calculated using the validation dataset. A model that included HAQ-DI, pain VAS, and DAS28 produced the highest adjusted R (2) as well as the lowest Akaike information criterion, RMSE, and MAE, regardless of the statistical methods used in modeling set. The mapping equation of the OLS method is given as EQ-5D = 0.95-0.21 × HAQ-DI-0.24 × pain VAS/100-0.01 × DAS28 (adjusted R (2) = 57.6 %, RMSE = 0.1654 and MAE = 0.1222). Also in the validation set, the RMSE and MAE were shown to be the smallest. The model with HAQ-DI, pain VAS, and DAS28 showed the best performance, and this mapping model enabled the estimation of an EQ-5D value for RA patients in whom utility values have not been measured.

Routine Assessment of Patient Index Data (RAPID3) and Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) Scores Yield Similar Information in 85 Korean Patients With Ankylosing Spondylitis Seen in Usual Clinical Care.

BACKGROUND: Disease-specific ankylosing spondylitis (AS) indices, including BASDAI (Bath AS Disease Activity Index), BASFI (Bath AS Functional Index), ASDAS (AS Disease Activity Score), and BASMI (Bath AS Metrology Index), are widely used in clinical trials and in some clinical settings, but not in most routine care. Laboratory tests usually are the only quantitative measures included in routine care of AS patients, but often are poorly informative. Routine Assessment of Patient Index Data 3 (RAPID3) on a Multidimensional Health Assessment Questionnaire (MDHAQ) is feasible and informative in many rheumatic diseases. OBJECTIVE: The aim of this study was to compare RAPID3 to BASDAI, BASFI, ASDAS, and BASMI in a cross-sectional analysis of 85 Korean AS patients collected in routine care. METHODS: MDHAQ/RAPID3, BASDAI, and BASFI were completed by patients, and ASDAS and BASMI assessed by health professionals. Indices and individual measures were compared using correlations, cross tabulations, scatter plots, and κ statistics. RESULTS: RAPID3 scores were correlated significantly with BASDAI (ρ = 0.82) and ASDAS-ESR (erythrocyte sedimentation rate) (ρ = 0.76), at levels similar to the correlation of BASDAI with ASDAS-ESR (ρ = 0.81). All 21 patients with BASDAI scores of 4 or greater, indicating active AS, were among 39 patients who had RAPID3 scores of greater than 12, indicating high severity, whereas 79% of 33 patients with ASDAS of greater than 1.3, indicating high activity, had RAPID3 high severity. CONCLUSIONS: RAPID3 gives similar information to BASDAI and ASDAS in AS patients, in this limited cross-sectional study from 1 setting. Ankylosing spondylitis-specific measures are needed for clinical trials, but poorly feasible in most busy clinical settings. The MDHAQ/RAPID3 offers pragmatic quantitative clinical assessment of AS patients in routine care.

Awareness of chronic obstructive pulmonary disease in current smokers: a nationwide survey.

BACKGROUND/AIMS: Cigarette smoking is the most common risk factor for chronic obstructive pulmonary disease (COPD). However, few studies of the attitudes toward COPD of smokers, the group at risk of developing this condition, have been conducted. The purpose of this study was to explore the awareness of and attitudes toward COPD of current smokers. METHODS: The sample consisted of 502 individuals aged 45 and older from throughout Korea who smoked at least 10 packs of cigarettes per year. Telephone interviews using a structured questionnaire were conducted with respondents. RESULTS: First, we evaluated the health status of subjects, finding that 45.4% considered themselves to be in good health. We also asked about COPD-related symptoms, and 60.6% of subjects reported such symptoms. However, only 1.2% of subjects had been diagnosed with or treated for COPD, only 0.4% spontaneously mentioned COPD as a respiratory disease, and only 26.5% recognized COPD as a respiratory disease after seeing a list of such diseases. Television ranked as the top source of information about COPD. The willingness of 45.0% of subjects to stop smoking increased after being informed about COPD. CONCLUSIONS: Despite having COPD-related symptoms, most smokers did not know that COPD is a respiratory disease. The attitudes of smokers toward COPD and smoking cessation varied according to socioeconomic status. In summary, a continuous effort to increase the awareness of COPD among smokers is needed. Additionally, strategies tailored according to different socioeconomic groups will also be necessary.

Resting energy expenditure is not associated with disease activity in women with rheumatoid arthritis: cross-sectional study.

BACKGROUND/AIMS: Increased resting energy expenditure (REE) in rheumatoid arthritis (RA) patients is thought to be caused by hypermetabolism associated with production of proinflammatory cytokines. Our aim in the present study was to explore the possible association between REE and disease activity in females with RA. METHODS: A total of 499 female RA patients were recruited to this cross-sectional study assessing REE scores on disease activity indices (the routine assessment of patient index data 3 [RAPID3], the disease activity score 28, and the clinical/simplified disease activity index [CDAI/SDAI]) and the levels of RA-associated autoantibodies (rheumatoid factor and anticyclic citrullinated peptide [anti-CCP] antibodies). Age-matched healthy female controls (n = 131) were also enrolled. RESULTS: REE did not differ between RA patients (all patients, and those in remission or not) and controls, or between RA patients in remission or not (p > 0.05 for all comparisons). Increased REE in total RA patients was associated with younger age and a higher body mass index (BMI) (p < 0.001 and p < 0.001, respectively), but not with disease activity index scores on any of RAPID3, CDAI, or SDAI. BMI was the only clinical parameter exhibiting a significant relationship with REE quartiles (Q1 to Q4; p < 0.001); none of disease duration, functional status, or anti-CCP antibody titer in RA patients was significantly related to REE, based on analysis of covariance. CONCLUSIONS: We found no association between REE and disease activity in RA patients, implying that energy metabolism in RA patients might be independent of RA-associated systemic inflammation.

Performance of Routine Assessment of Patient Index Data 3 (RAPID3) for assessment of rheumatoid arthritis in clinical practice: differential agreement of RAPID3 according to disease activity categories.

To evaluate the performance of Routine Assessment of Patient Index Data 3 (RAPID3) with the disease activity score 28 (DAS28) and the clinical/simplified disease activity index (CDAI/SDAI) in a Korean population with rheumatoid arthritis (RA). Four hundred patients with RA were consecutively enrolled. All patients completed disease activity indices such as RAPID3, DAS28, SDAI, and CDAI. The kappa and/or weighted coefficients were used to assess agreement between RAPID3 and other disease activity indices. ANOVA, Mantel-Haenszel chi-square test, and Spearman's partial correlation analysis were used for analyses. RAPID3 scores were significantly correlated with DAS28 (r = 0.62), SDAI (r = 0.74), and CDAI (r = 0.75; p < 0.0001 for all indices) and other activity measures including swollen/tender joint counts, erythrocyte sediment rate, and C-reactive protein. The weighted kappa coefficients of RAPID3 with DAS28, SDAI, and CDAI among the four disease activity categories were 0.33, 0.34, and 0.33, respectively. Kappa coefficients for RAPID3 in two disease activity categories increased more than four categories (κ = 0.40-0.42) indicating fair agreement. More than 86 % of patients with high-to-moderate disease activity in DAS28, CDAI, and SDAI had high-to-moderate disease activity using RAPID3 criteria. However, approximately 50 % of patients with remission-to-low disease activity in DAS28, CDAI, and SDAI showed remission-to-low disease activity in RAPID3. This study confirms RAPID3 as an informative disease activity index with equivalent values in DAS28, CDAI, and SDAI. RAPID3 reveals differential agreement in patients with lower disease activity.

Mortality after in-hospital cardiopulmonary resuscitation: multicenter analysis in Korea.

PURPOSE: The purpose of this study is to evaluate factors associated with the mortality of patients admitted to intensive care units (ICUs) after in-hospital cardiopulmonary resuscitation (CPR) and the impact of a hospital rapid response system (RRS) on patient mortality in Korea. MATERIALS AND METHODS: A prospective multicenter cohort study was done in 22 ICUs of 15 centers from July 1, 2010, to January 31, 2011. We only enrolled patients admitted to ICUs after in-hospital CPR and divided eligible patients into 2 groups-survivors and nonsurvivors. RESULTS: Among 4617 patients, 150 patients were admitted post-CPR, 76 died, and 74 survived. At 24 hours, the Sequential Organ Failure Assessment score, Simplified Acute Physiology Score II, and the best Glasgow Coma Scale were significantly lower in the nonsurvivors than in the survivors. In multivariate analysis, the Simplified Acute Physiology Score II and presence of lower respiratory infection were both independently associated with mortality. At the first hour after admission, lowest serum potassium and highest heart rate were associated with mortality. At 24 hours after admission, lowest mean arterial pressure, HCO3 level, and venous oxygen saturation level; highest heart rate; and use of vasoactive drugs were associated with mortality. The mortality of patients in hospitals with an RRS was not significantly different from that of hospitals without an RRS. CONCLUSION: Various physiologic and laboratory parameters were associated with the mortality of post-CPR ICU admitted patients, and the presence of an RRS did not reduce mortality of these patients in our study.

Chronic obstructive pulmonary disease assessment test can predict depression: a prospective multi-center study.

This study was conducted to investigate the association between the chronic obstructive pulmonary disease (COPD) assessment test (CAT) and depression in COPD patients. The Korean versions of the CAT and patient health questionnaire-9 (PHQ-9) were used to assess COPD symptoms and depressive disorder, respectively. In total, 803 patients with COPD were enrolled from 32 hospitals and the prevalence of depression was 23.8%. The CAT score correlated well with the PHQ-9 score (r=0.631; P<0.001) and was significantly associated with the presence of depression (ß±standard error, 0.452±0.020; P<0.001). There was a tendency toward increasing severity of depression in patients with higher CAT scores. By assessment groups based on the 2011 Global Initiative for Chronic Obstructive Lung Disease guidelines, the prevalence of depression was affected more by current symptoms than by airway limitation. The area under the receiver operating characteristic curve for the CAT was 0.849 for predicting depression, and CAT scores ≥21 had the highest accuracy rate (80.6%). Among the eight CAT items, energy score showed the best correlation and highest power of discrimination. CAT scores are significantly associated with the presence of depression and have good performance for predicting depression in COPD patients.

Assessment of liver fibrosis by transient elastography in rheumatoid arthritis patients treated with methotrexate.

OBJECTIVE: This study was designed to assess the degree of liver fibrosis with transient elastography and noninvasive biochemical methods in rheumatoid arthritis patients treated with methotrexate. METHODS: We reviewed the medical records of rheumatoid arthritis patients who were administered methotrexate for more than 3 years. Transient elastography was performed and serological markers of liver fibrosis were evaluated by prospectively and was compared with the result of healthy control group. A correlation of the cumulative dose of methotrexate with the elastography value (kPa) or the level of serological markers was assessed. Two subgroups of patients were compared; patients who received a cumulative dose of methotrexate of less than 4000 mg (group 1) and more than 4000 mg (group 2). A total of 177 consecutive rheumatoid arthritis patients were evaluated. RESULTS: The mean cumulative dose of methotrexate was 3988 ± 1566 mg with doses ranging from 652.5 to 10,415 mg. The mean elastography value of all patients was 4.01 ± 0.77 kPa. The kilopascal values and levels of biochemical markers did not correlate with the cumulative dose of methotrexate, but did correlate with the AST to ALT ratio, AST to platelet ratio index, haptoglobin level. Mean kilopascal values were not statistically different for group 1 and group 2 patients. For rheumatoid arthritis patients treated with a high cumulative dose of methotrexate, significant liver fibrosis is rare and is not accurately detected in patients with liver enzyme abnormalities. CONCLUSION: Taking into account the risk and benefit of a liver biopsy, transient elastography can be recommended as an additional diagnostic option.

Microbiological quality assessment of laboratory mice in Korea and recommendations for quality improvement.

Regular monitoring of commercial laboratory rodents and institutional research animal residents is essential for microbiological quality control programs. The objective of our study was to investigate the recent prevalence of infectious pathogens in laboratory mice from eight experimental animal vendors and 56 institutional animal facilities in Korea. Our investigation was conducted in 2006-2007. Specific Pathogen Free (SPF) mice from four commercial breeders were clean according to serological, bacteriological, parasitological, and histopathological examination results. However, mice from one intermediate vendor that distributed SPF animals from main commercial vendors to local districts had Syphacia obvelata and Mycoptes musculinus infections. Additionally, mice from conventional animal breeders were highly contaminated. Among the 56 institutional animal facilities, mouse hepatitis virus (MHV), Sendai virus and Mycoplasma pulmonis positive results were obtained in 23.2, 8.9, and 1.8% of animals tested, respectively. These results indicate that quarantine and eradication efforts of infectious pathogens in these facilities are sub-optimal and need to be improved. The use of commercial conventional mice for research should be eliminated and appropriate vendor selection as well as thorough quarantine before releasing animals into a facility are needed. Finally we suggest qualified veterinary experts are needed at each animal facility to ensure an adequate health surveillance program.