Socioeconomic burden of pneumonia due to multidrug-resistant Acinetobacter baumannii and Pseudomonas aeruginosa in Korea.

We aimed to estimate the socioeconomic burden of pneumonia due to multidrug-resistant Acinetobacter baumannii (MRAB) and Pseudomonas aeruginosa (MRPA). We prospectively searched for MRAB and MRPA pneumonia cases and matched them with susceptible-organism pneumonia and non-infected patients from 10 hospitals. The matching criteria were: same principal diagnosis, same surgery or intervention during hospitalisation, age, sex, and admission date within 60 days. We calculated the economic burden by using the difference in hospital costs, the difference in caregiver costs, and the sum of productivity loss from an unexpected death. We identified 108 MRAB pneumonia [MRAB-P] and 28 MRPA pneumonia [MRPA-P] cases. The estimated number of annual MRAB-P and MRPA-P cases in South Korea were 1309-2483 and 339-644, with 485-920 and 133-253 deaths, respectively. The annual socioeconomic burden of MRAB-P and MRPA-P in South Korea was $64,549,723-122,533,585 and $15,241,883-28,994,008, respectively. The results revealed that MRAB-P and MRPA-P occurred in 1648-3127 patients, resulted in 618-1173 deaths, and caused a nationwide socioeconomic burden of $79,791,606-151,527,593. Multidrug-resistant organisms (MDRO) impose a great clinical and economic burden at a national level. Therefore, controlling the spread of MDRO will be an effective measure to reduce this burden.

Three-year outcome of rapid HIV testing at public health centers in Seoul, Republic of Korea: a short report.

Before 2014, the only test used for anonymous voluntary human immunodeficiency virus (HIV) screening at public health centers (PHCs) in the Republic of Korea was an enzyme-linked immunosorbent assay (ELISA), which takes around 3 days to obtain results. In 2014, to encourage voluntary anonymous HIV screening tests, the Seoul Metropolitan Government adopted a rapid HIV screening test at PHCs. The rapid HIV screening test was introduced at four PHCs in 2014 and all 25 PHCs after 2015. We compared the numbers of HIV screening tests and confirmed positive individuals before and after introduction of the rapid HIV screening test. In 2012-2013, before the introduction of rapid HIV screening test, an average of 330 HIV screening tests were performed monthly (355 in 2012 and 305 in 2013) and 69 individuals were confirmed to have HIV in 2012 and 93 in 2013. After the introduction of the rapid HIV screening test, anonymous voluntary HIV screening increased to a monthly average of 447 tests in 2014, 2099 in 2015, and 2409 in 2016. These identified 38 new cases in 2014, 116 in 2015, and 143 in 2016. Adoption of the rapid HIV screening test has increased the number of HIV screening tests and confirmed cases.

Cost-Effectiveness of Voluntary HIV Testing Strategies in a Very Low-Prevalence Country, the Republic of Korea.

BACKGROUND: The Republic of Korea has a very low prevalence of human immunodeficiency virus (HIV) infection, but the number of new HIV diagnoses has steadily risen, strongly indicating a large number of undetected HIV infections. Thus, it is important for Korean public health authorities to adopt and encourage cost-effective HIV detection tools, such as rapid HIV screening tests. In this study, we aimed to evaluate the cost-effectiveness of enzyme-linked immunosorbent assays (ELISA) and rapid tests in a public health center (PHC) setting. METHODS: We developed a decision analytic model to assess the per-examinee cost and the cost-effectiveness of identifying HIV patients in a PHC setting using two HIV testing strategies: conventional HIV screening by ELISA versus rapid HIV testing. Analysis was performed in two scenarios: HIV testing in an average-risk population and in a high-risk population. RESULTS: Compared to the ELISA, the rapid test was cost-saving and cost-effective. The per-examinee cost was USD 1.61 with rapid testing versus USD 3.38 with ELISA in an average-risk population, and USD 4.77 with rapid testing versus USD 7.62 with ELISA in a high-risk population. The cost of identifying a previously undiagnosed HIV case was USD 26,974 with rapid testing versus USD 42,237 with ELISA in an average-risk population, and USD 153 with rapid testing versus USD 183 with ELISA in a high-risk population. CONCLUSION: Rapid testing would be more cost-effective than using conventional ELISA testing for identifying previously undiagnosed HIV-infected cases in Korea, a country with extremely low HIV prevalence.

Risk factors for poor outcome in community-onset Clostridium difficile infection.

Background: A substantial portion of Clostridium difficile infection (CDI) cases occur in communities, and community-onset CDI (CO-CDI) can lead to serious complications including mortality. This study aimed to identify the risk factors for a poor outcome in CO-CDI. Methods: We performed a retrospective review of all inpatients with CDI, in a 1300-bed tertiary-care hospital in Korea, from 2008 through 2015. CO-CDI was defined as CDI occurring within 48 h of admission. Poor outcome was defined as follows: 1) all-cause 30-day mortality, 2) in-hospital mortality, or 3) surgery due to CDI. Results: Of a total 1256 CDIs occurring over 8 years, 152 (12.1%) cases were classified as CO-CDI and 23 (15.1%) had a poor outcome, including 22 (14.5%) cases of mortality and 2 (1.3%) cases of surgery. Patients with a poor outcome had a higher mean age than those without a poor outcome (75.8 vs. 69.6 years, p = 0.03). The proportion of men and prior proton pump inhibitor (PPI) use were significantly higher in the poor outcome group (65.2% vs. 41.9%, p = 0.04; 39.1% vs. 17.6%, p = 0.02, respectively). Multivariate binary logistic model showed that PPI use and anemia (hemoglobin < 10 g/dL) at presentation were significantly associated with a poor outcome (adjusted odds ratio [aOR], 3.76; 95% confidence interval [95CI], 1.26-11.21, aOR, 4.67; 95CI, 1.52-14.34, respectively). Conclusions: Clinicians should not only be aware of the possibility of CDI in the community setting but also pay more attention to PPI-using elderly patients with anemia in consideration of a poor outcome.

Adherence to antiretroviral therapy and factors affecting low medication adherence among incident HIV-infected individuals during 2009-2016: A nationwide study.

For ideal clinical benefit, human immunodeficiency virus (HIV)-infected individuals should receive continuous medication. This is the first nationwide antiretroviral therapy (ART) adherence study in Asia, where medication monitoring at national level is systemically available. We estimated the ART adherence of incident HIV-infected individuals and investigated factors affecting low medication adherence using the national health insurance (NHI) claims data from 2007 to 2016. Medication possession ratio (MPR) was used to measure medication adherence and risk factors were identified by multivariable logistic regression analysis. Of the 8,501 newly diagnosed HIV-infected individuals during 2009-2016 with at least one ART prescription, 70.4% of HIV patients had adequate adherence to ART defined as MPR ≥95%. Requiring prophylactic antibiotics, female gender, age of 0-19 and same or over 50 s compared to 30-39, and having a history of malignancy, lower socioeconomic status, not visiting tertiary hospital, and being diagnosed in the earlier years were risk factors for lower adherence (Odds ratio 1.7, 1.6, 1.6, 1.4, 1.6, 2.1, 1.2, and 1.6 to 3.8 respectively). Health authority should take into consideration of these modifiable and unmodifiable barriers to establish sustainable monitoring system at national level and to improve adherence.

Factors associated with intention to be tested for HIV among men who have sex with men in a country with a very low HIV prevalence.

This study examined factors associated with the intention to take an HIV test among men who have sex with men (MSM) in South Korea. An internet website-based survey was conducted among users of the only and largest online MSM website between 20 July 2016, and 20 August 2016. A total of 2915 participants completed the survey and answered questions related to sociodemographic information, health behaviors, sexual behaviors, and HIV testing history. Of these, 2587 (88.7%) participants responded as having an intention to take an HIV test. A multivariable logistic regression analysis revealed the following as having reduced the intention to undergo HIV testing: very good subjective health status and no sexual interactions during the last 6 months (Adjusted odds ratios [AOR] 0.45 and 0.54, respectively). In contrast, increased intention to take an HIV test was associated with being 20-29 years old, 30-39 years old, not paying or receiving money for sex, having a history of HIV testing, and taking an HIV test once per 12 months (AOR 2.64, 2.13, 1.54, 1.81, and 2.17, respectively). In conclusion, HIV testing among MSM in this study was associated with age, subjective health status, sex(es) of one's sexual partner(s) during the last 6 months, sexual risk behaviors, HIV testing history, and undergoing regular HIV testing.

Factors associated with medication adherence in patients with human immunodeficiency virus in South Korea.

This study aimed to identify the factors associated with medication adherence in human immunodeficiency virus (HIV) patients in South Korea. A cross-sectional study was conducted from six hospitals participating in the Nationwide Specialized Counseling Program for HIV infected patients from 22 February to 10 May 2010. A total of 300 HIV patients have completed a self-administered questionnaire. Among 300 patients, 230 patients had above 95% medication adherence. Binary logistic regression analysis revealed that having medical insurance (p = .003) and a good relationship with the medical team (p = .046) were the main factors affecting medication adherence in HIV patients. In conclusion, medical insurance through the National Health Insurance Service and a good relationship between HIV infected patients and physicians are the main influencing factors that impact medication adherence in countries with low economic barriers to treatment.

Comparison of characteristics of culture-negative pyogenic spondylitis and tuberculous spondylitis: a retrospective study.

BACKGROUND: Differences between the characteristics of culture positive pyogenic spondylitis (CPPS) and tuberculous spondylitis (TS) are well known. However, differences between the characteristics of culture negative pyogenic spondylitis (CNPS) and TS have not been reported; these would be more helpful in clinical practice especially when initial microbiologic examination of blood and/or biopsy tissue did not reveal the causative bacteria in patients with infectious spondylitis. METHODS: We performed a retrospective review of the medical records of patients with CNPS and TS. We compared the characteristics of 71 patients with CNPS with those of 94 patients with TS. RESULTS: Patients with TS had more previous histories of tuberculosis (9.9 vs 22.3 %, p = 0.034), simultaneous tuberculosis other than of the spine (0 vs 47.9 %, p < 0.001), and positive results in the interferon-gamma release assay (27.6 vs 79.2 %, p < 0.001). Fever (15.5 vs. 31.8 %, p = 0.018), psoas abscesses (15.5 vs 33.0 %, p = 0.011), and paravertebral abscesses (49.3 vs. 74.5 %, p = 0.011) were also more prevalent in TS than CNPS. CONCLUSIONS: Different from or contrary to the previous comparisons between CPPS and TS, fever, psoas abscesses, and paravertebral abscesses are more common in patients with TS than in those with CNPS.

Clinical Progression and Cytokine Profiles of Middle East Respiratory Syndrome Coronavirus Infection.

Clinical progression over time and cytokine profiles have not been well defined in patients with Middle East respiratory syndrome coronavirus (MERS-CoV) infection. We included 17 patients with laboratory-confirmed MERS-CoV during the 2015 outbreak in Korea. Clinical and laboratory parameters were collected prospectively. Serum cytokine and chemokine levels in serial serum samples were measured using enzyme-linked immunosorbent assay. All patients presented with fever. The median time to defervescence was 18 days. Nine patients required oxygen supplementation and classified into severe group. In the severe group, chest infiltrates suddenly began to worsen around day 7 of illness, and dyspnea developed at the end of the first week and became apparent in the second week. Median time from symptom onset to oxygen supplementation was 8 days. The severe group had higher neutrophil counts during week 1 than the mild group (4,500 vs. 2,200/µL, P = 0.026). In the second week of illness, the severe group had higher serum levels of IL-6 (54 vs. 4 pg/mL, P = 0.006) and CXCL-10 (2,642 vs. 382 pg/mL, P < 0.001). IFN-α response was not observed in mild cases. Our data shows that clinical condition may suddenly deteriorate around 7 days of illness and the serum levels of IL-6 and CXCL-10 was significantly elevated in MERS-CoV patients who developed severe diseases.

Implementing the Use of Rapid HIV Tests in Public Health Centers in Seoul: Results of a Pilot Project, 2014.

To determine whether rapid HIV tests in public health centers might encourage voluntary HIV testing, a pilot project was conducted in four selected public health centers in Seoul, 2014. During the period April 10 to November 28 of pilot project, 3,356 rapid tests were performed, and 38 were confirmed as positive. The monthly average numbers of voluntary HIV tests and HIV-positive cases were up to nine-fold and six-fold larger, respectively, than those of the period before application of the rapid HIV test. Among 2,051 examinees that completed questionnaires, 90.3% were satisfied. In conclusion, the use of rapid HIV tests in public health centers promoted voluntary HIV testing and was satisfactory for examinees.

Differences in characteristics between first and breakthrough neutropenic fever after chemotherapy in patients with hematologic disease.

OBJECTIVE: This study was conducted to compare the clinical and microbiological characteristics of first and breakthrough neutropenic fever in hematologic malignancy patients after chemotherapy. METHODS: Breakthrough neutropenic fever was any episode of fever, not present initially, that developed either during antibiotic therapy or within 1 week of discontinuation of therapy. A total of 687 neutropenic fever episodes in 241 patients were observed from April 2003 to March 2014. RESULTS: Blood cultures revealed 210 causative microorganisms: 199 (94.8%) were bacteria and 11 (5.2%) were fungi. Gram-negative bacteria predominated in both types of neutropenic episode (first 75% (120/160) vs. breakthrough 56% (18/32)) and the most common pathogen was Escherichia coli. Antibiotic resistance rates were higher in breakthrough episodes than first episodes (piperacillin/tazobactam 6% vs. 31%, p=0.006; ceftazidime 9% vs. 31%, p=0.025). Inappropriate empirical antibiotic treatment was also more frequent (0% vs. 19%, p=0.001), as was the 30-day mortality rate (4.3% (19/442) vs. 7.9% (19/245), p=0.058), although the latter effect was not statistically significant. CONCLUSION: It is concluded that the epidemiological profile of breakthrough neutropenic fever is different from that of first episode fever. These data reinforce the view that pooled reporting of neutropenic fever may be misleading, and that clinicians should approach breakthrough fever as a distinct entity.

Immune reconstitution inflammatory syndrome versus non-immune reconstitution inflammatory syndrome lymphoma in HIV patients on antiretroviral therapy.

Little is known about differences between immune reconstitution inflammatory syndrome (IRIS) and non-IRIS lymphoma in HIV patients on antiretroviral therapy (ART). The aim of this study was to describe the characteristics of IRIS and non-IRIS lymphoma in Korean HIV-positive patients on ART compared with lymphoma in those off ART. Of 1490 patients, 41 (3%) had lymphoma. Of these, 27 cases (66%) were classified as lymphoma off ART, eight as IRIS lymphoma, and six as non-IRIS lymphoma on ART. Hodgkin lymphoma was significantly more common among patients with non-IRIS lymphoma on ART than among those with lymphoma off ART (P = 0.005), whereas there was no Hodgkin lymphoma among IRIS lymphoma. Stage IV lymphoma was significantly rarer in non-IRIS lymphoma on ART than in lymphoma off ART (P = 0.007). Non-IRIS lymphoma on ART tends to have a better survival rate than lymphoma off ART (Kaplan-Meier survival analysis, P = 0.167), while IRIS lymphoma exhibited a survival rate similar to lymphoma off ART (P = 0.618). In Korean HIV-positive patients, there were significantly more cases of Hodgkin lymphoma of a less advanced stage in non-IRIS lymphoma on ART than in lymphoma off ART, in contrast to IRIS lymphoma.

Clinical outcomes of spontaneous bacterial peritonitis due to extended-spectrum beta-lactamase-producing Escherichia coli or Klebsiella pneumoniae: a retrospective cohort study.

PURPOSE: The aim of this study was to (1) evaluate the clinical outcomes of spontaneous bacterial peritonitis (SBP) due to extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli or Klebsiella pneumoniae (EK) and (2) investigate the relationship between the adequacy of initial antibiotic treatments and patient outcomes. METHODS: We conducted a retrospective cohort study of cirrhotic patients with SBP caused by EK. We evaluated the 30-day mortality rate and used Cox proportional hazard models to identify risk factors for mortality. RESULTS: Between January 2006 and December 2012, a total of 231 episodes of SBP due to EK were recorded. Among them, 52 were caused by ESBL-producing EK (ESBL-EK). The 30-day mortality rate was significantly higher in patients with SBP due to ESBL-EK than in those with non-ESBL-producing EK (non-ESBL-EK) (34.6 vs. 18.4 %, respectively; p = 0.013). Multivariate analysis revealed that ESBL production [adjusted HR (aHR) 1.82, 95 % confidence interval (CI) 1.00-3.31], nosocomial infection (aHR 2.24, 95 % CI 1.26-3.95), septic shock (aHR 4.84, 95 % CI 2.70-8.65), higher Child-Pugh score (aHR 1.57, 95 % CI 1.28-1.92), and higher Charlson comorbidity index (aHR 1.37, 95 % CI 1.15-1.64) were independent risk factors for 30-day mortality in the total cohort. When we analyzed patients with SBP due to ESBL-EK separately, septic shock (aHR 3.64, 95 % CI 1.40-9.77), accompanying bacteremia (aHR 3.71, 95 % CI 1.37-10.08), and hepatocellular carcinoma (aHR 3.21, 95 % CI 1.20-8.56) were independent risk factors. CONCLUSIONS: Both 7- and 30-day mortalities for SBP due to ESBL-EK were significantly higher than for SBP due to non-ESBL-EK. Initial antibiotic choice was not associated with poor clinical outcomes in patients with SBP due to ESBL-EK.

The predictability of claim-data-based comorbidity-adjusted models could be improved by using medication data.

BACKGROUND: Recently, claim-data-based comorbidity-adjusted methods such as the Charlson index and the Elixhauser comorbidity measures have been widely used among researchers. At the same time, there have been an increasing number of attempts to improve the predictability of comorbidity-adjusted models. We tried to improve the predictability of models using the Charlson and Elixhauser indices by using medication data; specifically, we used medication data to estimate omitted comorbidities in the claim data. METHODS: We selected twelve major diseases (other than malignancies) that caused large numbers of in-hospital mortalities during 2008 in hospitals with 700 or more beds in South Korea. Then, we constructed prediction models for in-hospital mortality using the Charlson index and Elixhauser comorbidity measures, respectively. Inferring missed comorbidities using medication data, we built enhanced Charlson and Elixhauser comorbidity-measures-based prediction models, which included comorbidities inferred from medication data. We then compared the c-statistics of each model. RESULTS: 247,712 admission cases were enrolled. 55 generic drugs were used to infer 8 out of 17 Charlson comorbidities, and 106 generic drugs were used to infer 14 out of 31 Elixhauser comorbidities. Before the inclusion of comorbidities inferred from medication data, the c-statistics of models using the Charlson index were 0.633-0.882 and those of the Elixhauser index were 0.699-0.917. After the inclusion of comorbidities inferred from medication data, 9 of 12 models using the Charlson index and all of the models using the Elixhauser comorbidity measures were improved in predictability but, the differences were relatively small. CONCLUSION: Prediction models using Charlson index or Elixhauser comorbidity measures might be improved by including comorbidities inferred from medication data.

Disseminated penicilliosis in a Korean human immunodeficiency virus infected patient from Laos.

Penicillium marneffei may cause life-threatening systemic fungal infection in immune-compromised patients and it is endemic in Southeast Asia. A 39-yr-old HIV-infected male, living in Laos, presented with fever, cough, and facial vesiculopapular lesions, which had been apparent for two weeks. CT scans showed bilateral micronodules on both lungs; Pneumocystis jirovecii was identified by bronchoscopic biopsy. Despite trimethoprim-sulfamethoxazole and anti-tuberculosis medications, the lung lesions progressed and the facial lesions revealed central umbilications. Biopsy of the skin lesions confirmed disseminated penicilliosis, with the culture showing P. marneffei hyphae and spores. The P. marneffei was identified by rRNA PCR. A review of the bronchoscopic biopsy indicated penicilliosis. The patient completely recovered after being prescribed amphotericin-B and receiving antiretroviral therapy. This is the first case of penicilliosis in a Korean HIV-infected patient. It is necessary to consider P. marneffei when immunocompromised patients, with a history of visits to endemic areas, reveal respiratory disease.

Status of Plasmodium vivax malaria in the Republic of Korea, 2008-2009: decrease followed by resurgence.

The number of Plasmodium vivax malaria cases in the Republic of Korea (ROK) in 2008 was 1009, a 54.2% decrease on the previous year. It then resurged to 1317 cases in 2009 (30.5% increase on 2008). One possible cause for the sharp decrease in 2008 might be the large-scale presumptive anti-relapse therapy with primaquine that was undertaken in the Democratic People's Republic of Korea in 2007. Of the 2326 cases of P. vivax malaria diagnosed in the ROK during 2008-2009, 599 cases (25.8%) were military personnel, 535 cases (23.0%) were veterans, and 1192 cases (51.2%) were civilians. Local transmission within the ROK appeared to increase gradually, and the length of the transmission period of P. vivax malaria extended during this period. Parasite clearance time after chloroquine treatment has increased in the late 2000s, which requires the introduction of countermeasures against the decreasing chloroquine susceptibility, including reduction of mass chemoprophylaxis with chloroquine in the ROK Army.

Effect of salicylic acid on invasion of human vascular endothelial cells by Staphylococcus aureus.

Invasion of vascular endothelial cells by Staphylococcus aureus is associated with diverse complications and recurrent infection. Little is known about the effect of salicylic acid, the major metabolite of aspirin, on the interaction between S. aureus and vascular endothelial cells. We examined the adhesion of S. aureus strain 8325-4 cultured with or without salicylic acid to human umbilical vein endothelial cells (HUVECs), and the ability of the strain to invade these cells. Strain 8325-4 cells grown in salicylic acid were significantly less adherent to and invasive in HUVECs. Production of cytokine interleukin (IL)-6 was lower from the HUVECs infected with clinical isolates of S. aureus cultured in salicylic acid compared with those unexposed to salicylic acid. This study raises the possibility of using salicylic acid as an adjuvant therapeutic agent in the treatment of S. aureus bacteremia to prevent its complications or recurrence.