The impact of production of extended-spectrum ß-lactamases on the 28-day mortality rate of patients with Proteus mirabilis bacteremia in Korea.

BACKGROUND: The incidence of Proteus mirabilis antimicrobial resistance, especially that mediated by extended-spectrum ß-lactamases (ESBLs), has increased. We investigated the impact of ESBL production on the mortality of patients with P. mirabilis bacteremia in Korea. METHODS: Patients diagnosed with P. mirabilis bacteremia between November 2005 and December 2013 at a 2000-bed tertiary care center in South Korea were included in this study. Phenotypic and molecular analyses were performed to assess ESBL expression. Characteristics and treatment outcomes were investigated among ESBL-producing and non-ESBL-producing P. mirabilis bacteremia groups. A multivariate analysis of 28-day mortality rates was performed to evaluate the independent impact of ESBLs. RESULTS: Among 62 P. mirabilis isolates from 62 patients, 14 expressed ESBLs (CTX-M, 2; TEM, 5; both, 6; other, 1), and the 28-day mortality rate of the 62 patients was 17.74%. No clinical factor was significantly associated with ESBL production. The 28-day mortality rate in the ESBL-producing group was significantly higher than that in the non-ESBL-producing group (50% vs. 8.3%, p = 0.001). A multivariate analysis showed that ESBL production (odds ratio [OR], 11.53, 95% confidence interval [CI], 2.11-63.05, p = 0.005) was independently associated with the 28-day mortality rate in patients with P. mirabilis bacteremia. CONCLUSIONS: ESBL production is significantly associated with mortality in patients with bacteremia caused by P. mirabilis. Rapid detection of ESBL expression and prompt appropriate antimicrobial therapy are required to reduce mortality caused by P. mirabilis bacteremia.

Pooled nucleic acid testing to identify antiretroviral treatment failure during HIV infection in Seoul, South Korea.

BACKGROUND: There have been various efforts to identify less costly but still accurate methods for monitoring the response to HIV treatment. We evaluated a pooling method to determine if this could improve screening efficiency and reduce costs while maintaining accuracy in Seoul, South Korea. METHODS: We conducted the first prospective study of pooled nucleic acid testing (NAT) using a 5 minipool + algorithm strategy versus individual viral load testing for patients receiving antiretroviral therapy (ART) between November 2011 and August 2012 at an urban hospital in Seoul, South Korea. The viral load assay used has a lower level of detection of 20 HIV RNA copies/ml, and the cost per assay is US$ 136. The 5 minipool +algorithm strategy was applied and 43 pooled samples were evaluated. The relative efficiency and accuracy of the pooled NAT were compared with those of individual testing. RESULTS: Using the individual viral load assay, 15 of 215 (7%) plasma samples had more than 200 HIV RNA copies/ml. The pooled NAT using the 5 minipool + algorithm strategy was applied to 43 pooled samples; 111 tests were needed to test all samples when virologic failure was defined at HIV RNA ≥ 200 copies/ml. Therefore, 104 tests were saved over individual testing, with a relative efficiency of 0.48. When evaluating costs, a total of US$ 14,144 was saved for 215 individual samples during 10 months. The negative predictive value was 99.5% for all samples with HIV RNA ≥ 200 copies/ml. CONCLUSIONS: The pooled NAT with 5 minipool + algorithm strategy seems to be a very promising approach to effectively monitor patients receiving ART and to save resources.

DECIPHERING GUT MICROBIOTA IN PATIENTS WITH SEVERE SEPSIS AND SEPTIC SHOCK.

ABSTRACT: Introduction: Gut microbiota dysbiosis is associated with susceptibility to sepsis and poor outcomes. However, changes to the intestinal microbiota during sepsis and their value as biomarkers are unclear. In this study, we compared the intestinal microbiota of patients with sepsis and healthy controls. Methods: Stool was collected from patients with sepsis (subdivided according to mortality) and controls. Microbiome diversity and composition were analyzed by 16S rRNA gene pyrosequencing. The α-diversity of the intestinal microbiome was determined using operational taxonomic unit counts and the Chao1, Shannon, and ACE indices. Adjusted Cox regression analyses assessed 6-month mortality risk factors. Results: Fifty-nine patients (14 in-hospital deaths) and 29 healthy controls were enrolled. Operational taxonomic unit counts and Chao1 and ACE indices were lower in the nonsurvivor than in the other groups. The controls showed a higher Shannon and lower Simpson index than did the sepsis group. The genus Blautia was more abundant in controls than in the sepsis group, and Faecalibacterium less abundant in the nonsurvivor than in the other groups. Regression analysis associated low Shannon index with 6-month mortality. Conclusions: Survivors of sepsis, nonsurvivors, and healthy controls have different gut microbiomes, and a low Shannon index is a risk factor for 6-month mortality.

Characteristics of Faecal Microbiota in Korean Patients with Clostridioides difficile-associated Diarrhea.

BACKGROUND: The intestinal microbiota plays an important role in the pathogenesis of Clostridioides difficile-associated diarrhea, and regional and racial characteristics influence the microbiome composition and diversity. We investigated the intestinal microbiome characteristics of patients with C. difficile colitis (CD+) compared to those of patients with colitis not due to C. difficile (CD-), patients with vancomycin-resistant enterococci (VRE) colonization, and healthy controls, in Korea. MATERIALS AND METHODS: We collected stool samples from 24, 18, 11 and 13 subjects within CD+, CD-, VRE and healthy control groups, respectively. The microbial communities were evaluated by 454-pyrosequencing of bacterial 16s rRNA. RESULTS: The species richness and microbial diversity were significantly lower in the CD+ group compared to those in healthy controls, but not compared to those in CD- and VRE groups. Phylum-level analysis showed that the proportion of Actinobacteria in the CD+ group was significantly lower than in the healthy control, but was unchanged compared to that in CD- and VRE groups. At the genus level, compared to the healthy group, the CD+ group showed significantly lower proportions of Blautia, Bifidobacterium, Faecalibacterium et al. Compared to the VRE group, the CD+ group showed a significantly higher proportion of Anaerostipes. CONCLUSIONS: We could identify the intestinal microbiome characteristics of Koreans with C. difficile colitis. It might help to develop microbiome based diagnostic and treatment modalities.

Correction: The C-reactive protein/albumin ratio as an independent predictor of mortality in patients with severe sepsis or septic shock treated with early goal-directed therapy.

[This corrects the article DOI: 10.1371/journal.pone.0132109.].

Effects of Early Exercise Rehabilitation on Functional Recovery in Patients with Severe Sepsis.

PURPOSE: Severe sepsis is associated with functional disability among patients surviving an acute phase of infection. Efforts to improve functional impairment are important. We assessed the effects of early exercise rehabilitation on functional outcomes in patients with severe sepsis. MATERIALS AND METHODS: A prospective, single-center, case-control study was conducted between January 2013 and May 2014 at a tertiary care center in Korea. Patients with severe sepsis and septic shock were enrolled and randomized to receive standard sepsis treatment or intervention. Intervention involved early targeted physical rehabilitation with sepsis treatment during hospitalization. Participants were assessed at enrollment, hospital discharge, and 6 months after enrollment. Functional recovery was measured using the Modified Barthel Index (MBI), Functional Independence Measure (FIM), and Instrumental Activities of Daily Living (IADL). RESULTS: Forty participants (21 intervention patients) were included in an intention-to-treat analysis. There were no significant differences in baseline MBI, FIM, and IADL between groups. Intervention yielded greater improvement of MBI, FIM, and IADL in the intervention group at hospital discharge, but not significantly. Subgroup analysis of patients with APACHE II scores ≥10 showed significantly greater improvement of physical function at hospital discharge (MBI and FIM) in the intervention group, compared to the control group (55.13 vs. 31.75, p=0.048; 52.40 vs. 31.25, p=0.045). Intervention was significantly associated with improvement of MBI in multiple linear regression analysis (standardized coefficient 0.358, p=0.048). CONCLUSION: Early physical rehabilitation may improve functional recovery at hospital discharge, especially in patients with high initial severity scores.

An Imported Case of Brucella melitensis Infection in South Korea.

Brucellosis is a zoonotic infection that is usually transmitted from cattle to humans through ingestion of animal milk, direct contact with animal parts, or inhalation of aerosolized particles. In Korea, brucellosis seem to be transmitted through close contact with blood, fetus, urine, and placenta of domestic cow that has been infected by Brucella abortus, or inhalation of B. arbortus while examining or slaughtering cow. Brucella melitensis infection is rare in Korea and there have been no reported cases of B. melitensis originating from other countries until now. This report details a case of complicated brucellosis with infective spondylitis in a 48-year-old male construction worker recently returned from Iraq. Infection with B. melitensis was confirmed using 16s rRNA sequencing and omp31 gene analysis. The patient was successfully treated using a combination of rifampin, doxycycline, and streptomycin, in accordance with WHO guidelines. This is the first reported case of complicated brucellosis with infective spondylitis in Korea caused by B. melitensis originating from Iraq.

A Case of Community-Acquired Pneumonia Caused by Multidrug-Resistant Acinetobacter baumannii in Korea.

Acinetobacter baumannii is an aerobic Gram-negative coccobacillus that causes nosocomial pneumonia in patients on mechanical ventilation or previously treated with broad-spectrum antibiotics. Nevertheless, community-acquired pneumonia (CAP) caused by A. baumannii, especially multi-drug resistant (MDR) strains, is rare. We experienced the first case of CAP caused by MDR A. baumannii in Korea in a 78-year-old man. This case shows that MDR A. baumannii can cause CAP in Korea.

Long Pentraxin 3 as a Predictive Marker of Mortality in Severe Septic Patients Who Received Successful Early Goal-Directed Therapy.

PURPOSE: Pentraxin 3 (PTX3) has been suggested to be a prognostic marker of mortality in severe sepsis. Currently, there are limited data on biomarkers including PTX3 that can be used to predict mortality in severe sepsis patients who have undergone successful initial resuscitation through early goal-directed therapy (EGDT). MATERIALS AND METHODS: A prospective cohort study was conducted among 83 severe sepsis patients with fulfillment of all EGDT components and the achievement of final goal. Plasma PTX3 levels were measured by sandwich ELISA on hospital day (HD) 0, 3, and 7. The data for procalcitonin, C-reactive protein and delta neutrophil index were collected by electric medical record. The primary outcome was 28-day all-cause mortality. RESULTS: 28-day all-cause mortality was 19.3% and the median (interquartile range) APHCH II score of total patients was 16 (13-19). The non-survivors (n=16) had significantly higher PTX3 level at HD 0 [201.4 (56.9-268.6) ng/mL vs. 36.5 (13.7-145.3) ng/mL, p=0.008]. PTX3 had largest AUC(ROC) value for the prediction of mortality among PTX3, procalcitonin, delta neutrophil index, CRP and APACHE II/SOFA sore at HD 0 [0.819, 95% confidence interval (CI) 0.677-0.961, p=0.008]. The most valid cut-off level of PTX3 at HD 0 was 140.28 ng/mL (sensitivity 66.7%, specificity 73.8%). The PTX3 and procalcitonin at HD 0 showed strong correlation (r=0.675, p<0.001). However, PTX3 at HD 0 was the only independent predictive marker in Cox's proportional hazards model (≥140 ng/mL; hazard rate 7.16, 95% CI 2.46-15.85, p=0.001). CONCLUSION: PTX3 at HD 0 could be a powerful predictive biomarker of 28-day all-cause mortality in severe septic patients who have undergone successful EGDT.

The incidence and clinical characteristics by gender differences in patients with Kikuchi-Fujimoto disease.

Kikuchi-Fujimoto disease (KFD) is a rare, self-limiting disorder that typically affects the cervical lymph nodes (LNs). Although initially described in young women, KFD also occurs in men. There are no reports on the clinical manifestations and characteristics of male KFD patients. Therefore, this study was conducted to assess the incidence of KFD among males, as well as the most frequent clinical characteristics of these patients. A retrospective, cross-sectional study was performed at a tertiary hospital of patients pathologically confirmed as having KFD from LN biopsy specimens. Clinical and laboratory data, and treatment outcomes of the enrolled patients, were analyzed by gender. A total of 254 patients diagnosed with KFD were enrolled. There were 189 females and 65 males (2.9:1). The mean age was 32.6 ±â€Š11.3 years. Compared to the female patients, the males had more frequent manifestations of fever (48% vs 67%, P = 0.008), headache (9% vs 20%, P = 0.013), bilateral lymphadenopathy (31% vs 46%, P = 0.029), thrombocytopenia (14% vs 29%, P = 0.014), elevated C-reactive protein (CRP) (35% vs 78.4%, P < 0.001), elevated liver enzymes (15% vs 41%, P < 0.001), and elevated lactate dehydrogenase (LDH) (61% vs 80%, P = 0.021). Male patients had fewer autoimmune features (9% vs 2%, P = 0.043) and fewer positive antinuclear antibodies (32% vs 10%, P = 0.006). In this study, 25.6% of the enrolled patients were male, with a 2.9:1 female-to-male sex ratio. Male patients showed a distinctive profile characterized by a higher frequency of fever, headache, bilateral lymphadenopathy, and thrombocytopenia, as well as elevated liver enzymes, CRP, and LDH.

Short Communication: HIV-1 Transmission Networks Across South Korea.

Molecular epidemiology can help clarify the properties and dynamics of HIV-1 transmission networks in both global and regional scales. We studied 143 HIV-1-infected individuals recruited from four medical centers of three cities in South Korea between April 2013 and May 2014. HIV-1 env V3 sequence data were generated (337-793 bp) and analyzed using a pairwise distance-based clustering approach to infer putative transmission networks. Participants whose viruses were ≤2.0% divergent according to Tamura-Nei 93 genetic distance were defined as clustering. We collected demographic, risk, and clinical data and analyzed these data in relation to clustering. Among 143 participants, we identified nine putative transmission clusters of different sizes (range 2-4 participants). The reported risk factor of participants were concordant in only one network involving two participants, that is, both individuals reported homosexual sex as their risk factor. The participants in the other eight networks did not report concordant risk factors, although they were phylogenetically linked. About half of the participants refused to report their risk factor. Overall, molecular epidemiology provides more information to understand local transmission networks and the risks associated with these networks.

A Case of Infective Endocarditis caused by Abiotrophia defectiva in Korea.

Abiotrophia defectiva, a nutritionally variant streptococci can cause bacteremia, brain abscess, septic arthritis and in rare cases, infective endocarditis, which accounts for 5-6% of all cases. A. defectiva is characteristically difficult to diagnose and the mortality, morbidity and complication rates are high. Here, we discuss a case of infective endocarditis caused by A. defectiva. A 62-year-old female had previously undergone prosthetic valve replacement 6 years prior to admission. She developed infective endocarditis after tooth extraction. Her endocarditis was successfully treated with antimicrobial therapy and mitral valve replacement surgery. This is the first case of infective endocarditis caused by A. defectiva reported in Korea. This case shows that A. defectiva could be considered as a causative organism of infective endocarditis in Korea.

Risk factors for mortality in patients with Stenotrophomonas maltophilia bacteremia.

Stenotrophomonas maltophilia is a nosocomial pathogen associated with high morbidity and mortality, particularly in immunocompromised or critically ill patients. In this study, we investigated the risk factors for mortality in patients with S. maltophilia bacteremia.Retrospectively, medical records from all patients with S. maltophilia bacteremia between December 2005 and 2014 at Severance Hospital, a 2000-bed tertiary care hospital in Seoul, Korea, were reviewed. Analysis was performed to identify factors associated with 28-day mortality.In total, 142 bacteremia patients were enrolled in this study. The overall 28-day mortality rate was 36.6%. Based on the univariate analysis, hematologic malignancy (P = 0.015), Sepsis-related Organ Failure Assessment (SOFA) score (P < 0.001) and the removal of a central venous catheter (CVC) (P = 0.040) were significantly related to mortality. In the intensive care unit patients, the Acute Physiology and Chronic Health Evaluation II score (P = 0.001) also had significance. Based on the multivariate analysis, the SOFA score (odds ratio [OR] = 1.323; 95% confidence interval [CI]: 1.159, 1.509; P < 0.001) and removal of the CVC (OR = 0.330; 95% CI: 0.109, 0.996; P = 0.049) were independent factors associated with mortality.Our results suggest that removing a CVC may considerably reduce mortality in patients with S. maltophilia bacteremia.

Fecal Transplantation using a Nasoenteric Tube during an Initial Episode of Severe Clostridium difficile Infection.

The incidence of Clostridium difficile infection is increasing worldwide, and its severity and resulting mortality are also on the rise. Metronidazole and oral vancomycin remain the treatments of choice, but there are concerns about treatment failure and the appearance of resistant strains. Furthermore, antibiotic therapy results in recurrence rates of at least 20%. Fecal transplantation may be a feasible treatment option for recurrent C. difficile infection; moreover, it may be an early treatment option for severe C. difficile infection. We report a case of severe C. difficile infection treated with fecal transplantation using a nasoenteric tube during an initial episode. This is the first reported case of fecal transplantation using a nasoenteric tube during an initial episode of C. difficile infection in Korea.

Characteristics of Resting-State Functional Connectivity in HIV-Associated Neurocognitive Disorder.

BACKGROUND: HIV-associated neurocognitive disorder (HAND) can occur in patients without prior AIDS defining illness and can be debilitating. This study aimed to evaluate the difference in the patterns of intrinsic brain activity between patients with or without HAND for deepening our understanding of HAND. METHODS: We evaluated 24 HIV-infected individuals, 12 with previously diagnosed HAND and 12 previously diagnosed without HAND, and 11 seronegative individuals. These individuals then underwent repeat NP testing and a functional brain MRI scan. For functional MRI analysis, seed-based analysis with bilateral precuneus cortex seed was applied. RESULTS: Among the 12 individuals with previously diagnosed HAND, 3 showed improvement of their neurocognitive function and 1 was excluded for worsening liver disease. Among the 12 patients who previously had normal neurocognitive function, 2 showed neurocognitive impairment. Overall, the HAND group, who had impaired cognitive function at the time of MRI scan, showed significant decrease of resting status functional connectivity between bilateral precuneus and prefrontal cortex (PFC) compared with nonHAND group, those who had normal neurocognitive function (Corrected P<0.05). The functional connectivity with the right inferior frontal operculum and right superior frontal gyrus was positively correlated with memory and learning ability. CONCLUSIONS: This cross-sectional study found a significant difference in fMRI patterns between patients with and without HAND. Decreased functional connectivity between precuneus and PFC could be possible functional substrate for cognitive dysfunction in HIV patients, which should be characterized in a longitudinal study.

Incidence of and risk factors for infectious complications in patients with cardiac device implantation.

OBJECTIVES: The use of cardiac implantable electronic device (CIED; pacemakers, implantable cardioverter-defibrillators [ICD], cardiac re-synchronized therapy [CRT]) implantation, one essential treatment for cardiac arrhythmias, is increasing. Infectious complications related to implants are the main reason for device removal and patient morbidity. We sought to identify the incidence of infectious complications among patients with cardiac device implantation and analyze the risk factors for infectious complications. METHODS: A retrospective analysis was conducted of 1307 patients (61.5±14.2 years-old, 49.6% male) with cardiac device implantation from January 1990 to April 2013. We analyzed the incidence of infectious complications during the follow-up period. To investigate risk factors associated with infectious complications, we conducted a 1:2 matched case-control study of patients with infectious complications and controls without infectious complications who had the same implantation period and physician. RESULTS: Among 1307 patients, 12 had a confirmed device-related infection: 7 with a pocket infection and 5 with infective endocarditis. Over a total of 9091.9 device-years, the incidence of infectious complications was 1.3/1000 device-years, based on the 12 patients with an infection. ICD (5.1/1000 device-year) had a higher incidence of infectious complications than other cardiac devices, and no infectious complications were observed among patients with CRT implantation. Mean duration from the time of implantation to infection was 2.02±1.65 years. In a multivariate analysis, the number of prior procedures including wound revision or scar revision was an independent risk factor for infectious complications (OR=10.88, 95% CI 1.11->999, p=0.040). CONCLUSIONS: Infection was a rare complication of cardiac device implantation, but repeated procedures were associated with infectious complications.

Risk factors for mortality in patients with Serratia marcescens bacteremia.

PURPOSE: Over the last 30 years, Serratia marcescens (S. marcescens) has emerged as an important pathogen, and a common cause of nosocomial infections. The aim of this study was to identify risk factors associated with mortality in patients with S. marcescens bacteremia. MATERIALS AND METHODS: We performed a retrospective cohort study of 98 patients who had one or more blood cultures positive for S. marcescens between January 2006 and December 2012 in a tertiary care hospital in Seoul, South Korea. Multiple risk factors were compared with association with 28-day all-cause mortality. RESULTS: The 28-day mortality was 22.4% (22/98 episodes). In a univariate analysis, the onset of bacteremia during the intensive care unit stay (p=0.020), serum albumin level (p=0.011), serum C-reactive protein level (p=0.041), presence of indwelling urinary catheter (p=0.023), and Sequential Oran Failure Assessment (SOFA) score at the onset of bacteremia (p<0.001) were significantly different between patients in the fatal and non-fatal groups. In a multivariate analysis, lower serum albumin level and an elevated SOFA score were independently associated with 28-day mortality [adjusted odds ratio (OR) 0.206, 95% confidential interval (CI) 0.044-0.960, p=0.040, and adjusted OR 1.474, 95% CI 1.200-1.810, p<0.001, respectively]. CONCLUSION: Lower serum albumin level and an elevated SOFA score were significantly associated with adverse outcomes in patients with S. marcescens bacteremia.

The C-Reactive Protein/Albumin Ratio as an Independent Predictor of Mortality in Patients with Severe Sepsis or Septic Shock Treated with Early Goal-Directed Therapy.

BACKGROUND: Sepsis, including severe sepsis and septic shock, is a major cause of morbidity and mortality. Albumin and C-reactive protein (CRP) are considered as good diagnostic markers for sepsis. Thus, initial CRP and albumin levels were combined to ascertain their value as an independent predictor of 180-day mortality in patients with severe sepsis and septic shock. MATERIALS AND METHODS: We conducted a retrospective cohort study involving 670 patients (>18 years old) who were admitted to the emergency department and who had received a standardized resuscitation algorithm (early goal-directed therapy) for severe sepsis and septic shock, from November 2007 to February 2013, at a tertiary hospital in Seoul, Korea. The outcome measured was 180-day all-cause mortality. A multivariate Cox proportional hazard model was used to identify the independent risk factors for mortality. A receiver operating characteristic (ROC) curve analysis was conducted to compare the predictive accuracy of the CRP/albumin ratio at admission. RESULTS: The 180-day mortality was 28.35% (190/670). Based on the multivariate Cox proportional hazard analysis, age, the CRP/albumin ratio at admission (adjusted HR 1.06, 95% CI 1.03-1.10, p<0.001), lactate level at admission (adjusted HR 1.10, 95% CI 1.05-1.14, p<0.001), and the Sequential Organ Failure Assessment (SOFA) score at admission (adjusted HR 1.12, 95% CI 1.07-1.18, p<0.001) were independent predictors of 180-day mortality. The area under the curve of CRP alone and the CRP/albumin ratio at admission for 180-day mortality were 0.5620 (P<0.001) and 0.6211 (P<0.001), respectively. CONCLUSION: The CRP/albumin ratio was an independent predictor of mortality in patients with severe sepsis or septic shock.

A Case of Rectal Squamous Cell Carcinoma with Metachronous Diffuse Large B Cell Lymphoma in an HIV-Infected Patient.

Diffuse large B cell lymphoma (DLBCL) is one of the most common acquired immune deficiency syndrome (AIDS)-defining malignancies among human immunodeficiency virus-infected patients, and rectal cancer has recently emerged as a prevalent non-AIDS-defining malignancy. We report a case of rectal squamous cell carcinoma that was metachronous with DLBCL in an HIV-infected patient who was receiving highly active antiretroviral therapy. The patient was diagnosed with DLBCL and showed complete remission after chemotherapy. Follow-up imaging showed increased uptake at the rectum, previously treated as lymphoma. Repeated biopsy was performed and squamous cell carcinoma of the rectum was reported. After concurrent chemoradiation therapy, curative resection was performed.

A nationwide survey of inhalant allergens sensitization and levels of indoor major allergens in Korea.

PURPOSE: The higher prevalence of respiratory allergic disease may be due to increased exposure to inhalation allergens. We conducted a survey of allergic diseases in autumn and winter with detection of major indoor allergens in major cities in Korea. METHODS: We enrolled 110 subjects from the fourth Korea National Health and Nutrition Examination Survey with stratified, cluster, and systematic sampling procedures. All participants answered a health questionnaire as well as underwent a skin prick test (SPT) and ImmunoCAP for 11 indoor major allergens. We also measured the levels of 5 major allergens (Der f 1, Der p 1, Can f 1, Bla g 1, and Asp f 1) in fine indoor dust from the houses of 60 subjects with a 2-site ELISA. RESULTS: The prevalence of allergic rhinitis and asthma were 25.5% and 7.3%, respectively. The most common sensitized allergens identified by SPT and ImmunoCAP were Dermatophagoides farinae (40.9%, 36.8%), followed by cockroach (23.6%, 19.5%), mugwort (13.6%, 22.9%), oak (9.1%, 22.9%), Japanese hop (9.1%, 8.6%), and dog dander (8.2%, 6.9%). There was a modest discrepancy between SPT and ImmunoCAP. Der f 1 and Der p 1 were detected in 91.7% and 45.0% of the enrolled houses, respectively. Der f 1 indicated high concentrations in all specific provinces in Korea; however, Der p 1 measured high only in the south. Dog dander allergens were present in 71.7% of houses; however, Bla g 1 was present in only 11.7% of houses and Asp f 1 was not detected in any houses. CONCLUSIONS: The most important inhalant allergens in Korea are house dust mites followed by cockroach, mugwort, oak, Japanese hop, and dog dander in indoor environment, in which The dominant species of house dust mites were different according to region.