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Introduction Middle East Respiratory Syndrome (MERS) caused by MERS‐coronavirus (CoV) is a lower respiratory tract disease characterized by a high mortality rate. MERS‐CoV spread from Saudi Arabia to other countries, including South Korea. Dysfunction of the human leukocyte antigen (HLA) system has many effects due to genetic complexity and its role in the adaptive immune response. We investigated the association of HLA class I and II alleles with MERS‐CoV in 32 patients with MERS. Methods HLA‐A, ‐B, ‐C, ‐DRB1, ‐DQB1, and ‐DPB1 were genotyped by polymerase chain reaction sequence‐based typing. Results HLA‐DQB1*03:02 are significantly associated with moderate/mild cases of MERS‐CoV. Other alleles are no statistical significance. Conclusions Treatment strategies based on current research on the HLA gene and MERS‐CoV will provide potential therapeutic targets.

Background Zoonotic coronaviruses have emerged as a global threat by causing fatal respiratory infections. Given the lack of specific antiviral therapies, application of human convalescent plasma retaining neutralizing activity could be a viable therapeutic option that can bridges this gap. Methods We traced antibody responses and memory B cells in peripheral blood collected from 70 recovered Middle East respiratory syndrome coronavirus (MERS-CoV) patients for 3 years after the 2015 outbreak in South Korea. We also used a mouse infection model to examine whether the neutralizing activity of collected sera could provide therapeutic benefit in vivo upon lethal MERS-CoV challenge. Results Anti-spike-specific IgG responses, including neutralizing activity and antibody-secreting memory B cells, persisted for up to 3 years, especially in MERS patients who suffered from severe pneumonia. Mean antibody titers gradually decreased annually by less than 2-fold. Levels of antibody responses were significantly correlated with fever duration, viral shedding periods, and maximum viral loads observed during infection periods. In a transgenic mice model challenged with lethal doses of MERS-CoV, a significant reduction in viral loads and enhanced survival was observed when therapeutically treated with human plasma retaining a high neutralizing titer (> 1/5000). However, this failed to reduce pulmonary pathogenesis, as revealed by pathological changes in lungs and initial weight loss. Conclusions High titers of neutralizing activity are required for suppressive effect on the viral replication but may not be sufficient to reduce inflammatory lesions upon fatal infection. Therefore, immune sera with high neutralizing activity must be carefully selected for plasma therapy of zoonotic coronavirus infection.

The rapid spread of severe acute respiratory coronavirus syndrome 2 (SARS-CoV-2) in the population and throughout the cells within our body has been developing. Another major cycle of coronavirus disease 2019 (COVID-19), which is expected in the coming fall, could be even more severe than the current one. Therefore, effective countermeasures should be developed based on the already obtained clinical and research information about SARS-CoV-2. The aim of this review was to summarize the data on the empirical treatment of COVID-19 acquired during this SARS-CoV-2 infection cycle; this would aid the establishment of an appropriate healthcare policy to meet the challenges in the future. The infectious disease caused by SARS-CoV-2 is characterized by common cold along with hypersensitivity reaction. Thus, in addition to treating common cold, it is essential to minimize the exposure of cells to the virus and to mitigate the uncontrolled immune response. A proper combination of antiviral agents, immune modulators such as prednisolone, and anticoagulants such as heparin and anti-C5a antagonists could be employed to minimize lung damage and prevent systemic involvements. Finally, strategies to achieve population immunity against SARS-CoV-2 should be developed through understanding of the interaction between the immune system and the virus.

Background The 2015 outbreak of Middle East Respiratory Syndrome (MERS) in the Republic of Korea is a recent and representative occurrence of nationwide outbreaks of Emerging Infectious Diseases (EIDs). In addition to physical symptoms, posttraumatic stress disorder (PTSD) and depression are common following outbreaks of EID. Methods The present study investigated the long-term mental health outcomes and related risk factors in survivors of MERS. A prospective nationwide cohort study was conducted 12 months after the MERS outbreak at multi-centers throughout Korea. PTSD and depression as the main mental health outcomes were assessed with the Impact of Event Scale-Revised Korean version (IES-R-K) and the Patient Health Questionnaire-9 (PHQ-9) respectively. Results 42.9% of survivors reported PTSD (IES-R-K ≥ 25) and 27.0% reported depression (PHQ-9 ≥ 10) at 12 months post-MERS. A multivariate analysis revealed that anxiety (adjusted odds ratio [aOR], 5.76; 95%CI, 1.29–25.58; P = 0.021), and a greater recognition of stigma (aOR, 11.09, 95%CI, 2.28–53.90; P = 0.003) during the MERS-affected period were independent predictors of PTSD at 12 months after the MERS outbreak. Having a family member who died from MERS predicted the development of depression (aOR, 12.08, 95%CI, 1.47–99.19; P = 0.020). Conclusion This finding implies that psychosocial factors, particularly during the outbreak phase, influenced the mental health of patients over a long-term period. Mental health support among the infected subjects and efforts to reduce stigma may improve recovery from psychological distress in an EID outbreak.

Objective The relationship among chronic fatigue, depressive symptoms, and post-traumatic stress symptoms (PTSSs) among Middle East respiratory syndrome (MERS) survivors is poorly understood. Methods Of 148 survivors who consented to be registered and underwent assessments at 12 months (T1) and 18 months (T2) after the MERS outbreak, 72 (48.65%) were evaluated for chronic fatigue, depressive symptoms, and PTSSs based on the Impact of Event ScaleRevised (IES-R), the Patient Health Questionnaire-9 (PHQ-9), and the Fatigue Severity Scale (FSS). Data from 52 subjects, who completed both assessments, were analyzed using a regression-based serial multiple mediation model (PROCESS Model 6). Results Bootstrap analyses indicated no direct effects of T1 FSS on T2 IES-R but significant positive indirect effects of T1 FSS on T2 IESR through T1 PHQ-9 and T2 PHQ-9 (B=2.1601, SE=1.3268, 95% confidence interval=0.4250-6.1307). In other words, both T1 PHQ-9 and T2 PHQ-9 fully mediated the relationship between T1 FSS and T2 IES. Conclusion Chronic fatigue 12 months after MERS had indirect effects on prolonged PTSSs 18 months after MERS via persisting depression in MERS survivors. This finding supports the need to promote interventional programs for emerging infectious disease survivors with chronic fatigue to reduce depression and prevent prolonged PTSSs.

Mixed-species malaria infections are often unrecognized or underestimated. We hereby report the first described case of mixed infection with Plasmodium falciparum and Plasmodium ovale malaria in a returned traveller in Korea. In August 2016, a 25-year-old returned traveller from Cameroon and Democratic Republic of Congo presented with fever. He was diagnosed as P. falciparum malaria and successfully treated with artesunate. And 5 weeks after the completion of treatment, he presented with fever and diagnosed as P. ovale infection. P. ovale infection is a rare cause of malaria and often shows delayed presentation due to its dormant liver stage as hypnozoites. At re-presentation, the immunochromatographic test and microscopic examinations of our patient did not reveal P. ovale, which was only detected via polymerase chain reaction (PCR) assay. This case highlights the importance of considering malaria infection even in persons who have previously received malaria treatment. It also shows the usefulness of PCR testing for diagnosing P. ovale infections, which often present with a low level of parasitaemia.

The present study investigated prevalence of integrase strand transfer inhibitors (INSTI) resistance mutations in HIV-1-infected antiretroviral therapy (ART)-naive patients in Korea. From 106 plasma samples, amplification and sequencing of integrase genes was performed, and major or minor mutations were calculated by the Stanford HIV drug resistance mutation interpretation algorithm. No major INSTI resistance mutations were found, and 14 minor mutations were detected in 13 (12.3%) patients. The present data support the recommendation that routine testing for INSTI resistance mutations before starting ART is not necessary.

Background An understanding of immune responses against the Middle East respiratory syndrome (MERS) is important for the development of treatments and preventive measures. Here, we investigated the spectrum of immune responses occurring in patients with MERS during the early period of infection. Methods We obtained peripheral blood samples from 27 hospitalized patients recruited during the epidemic that occurred in 2015 in South Korea. Plasma cytokines/chemokines and antibodies were quantified. Virus-specific T cells were examined by intracellular cytokine staining after stimulation of peripheral blood mononuclear cells with overlapping peptides spanning whole virus structural proteins. Results At the acute phase of infection, elevated levels of plasma proinflammatory cytokines/chemokines were detected in proportion to the severity of the disease. Distinctively high frequencies of MERS coronavirus–reactive CD8+ T cells were also observed in patients with severe/moderate illness, whereas antibody and CD4+ T-cell responses were minimally detected at this stage. At the convalescent phase, disease severity–dependent antibody responses emerged and antigen-reactive cells were identified in both T-cell subsets. These T cells belonged to the T-helper 1 or type 1 cytotoxic T cell subtypes. While CD8+ T cells responded preferentially to the viral S protein compared with E/M/N proteins, especially at the acute stage, slightly more CD4+ T cells recognized E/M/N proteins compared with S protein at the convalescent phase. Conclusions Our findings show an association between the early CD8+ T-cell response and the severity of the infection, and also provide basic information that may help to prepare effective control strategies for MERS in humans., Our study examined immune responses to MERS coronavirus at the acute stage of human infection, and shows an association between the early CD8+ T-cell response and the severity of the infection.

This nationwide, prospective cohort study evaluated pulmonary function and radiological sequelae according to infection severity in 73 survivors from the 2015 Middle East respiratory syndrome (MERS) outbreak in Korea. Patients with severe pneumonia in MERS-coronavirus infection had more impaired pulmonary function than those with no or mild pneumonia at the 1-year follow-up, which was compatible with the radiological sequelae. Severe pneumonia significantly impairs pulmonary function and makes long radiological sequelae in MERS., Graphical Abstract

A 68-year old man diagnosed with Middle East Respiratory Syndrome-Coronavirus (MERS-CoV) presented with multiple pneumonic infiltrations on his chest X-ray, and the patient was placed on a mechanical ventilator because of progressive respiratory failure. Urinary protein excretion steadily increased for a microalbumin to creatinine ratio of 538.4 mg/g Cr and a protein to creatinine ratio of 3,025.8 mg/g Cr. The isotope dilution mass spectrometry traceable serum creatinine level increased to 3.0 mg/dL. We performed a kidney biopsy 8 weeks after the onset of symptoms. Acute tubular necrosis was the main finding, and proteinaceous cast formation and acute tubulointerstitial nephritis were found. There were no electron dense deposits observed with electron microscopy. We could not verify the virus itself by in situ hybridization and confocal microscopy (MERS-CoV co-stained with dipeptidyl peptidase 4). The viremic status, urinary virus excretion, and timely kidney biopsy results should be investigated with thorough precautions to reveal the direct effects of MERS-CoV with respect to renal complications.

We describe a 49-year-old man with acute myelogenous leukemia associated with Sweet's syndrome and abscess-like lesions mimicking an infectious disease. Although blisters may be included in the clinical spectrum, frank non-infectious abscesses have not been reported as far as we know. Clinicians should be familiar with this clinical and histopathologic variant of Sweet's syndrome. It is mandatory to make every effort to find an infectious cause for abscesses before a diagnosis of Sweet's syndrome is made.

OBJECTIVES The aim of this study was to evaluate changes of body composition in cirrhotic patients. Dual energy x-ray absorptiometry (DEXA) and anthropometry were used, and the values obtained were compared. METHODS Mid-arm fat and muscle areas were calculated by anthropometry in 66 cirrhotic patients and 94 healthy controls. In 37 of the cirrhotic patients and 39 of the controls, fat mass, lean soft tissue mass and bone mineral contents were measured with DEXA. RESULTS The number of cirrhotic patients with measured values below the fifth percentile of normal controls was 21 (31.8%) by mid-arm fat area, six (9.1%) by mid-arm muscle area, 15 (40.5%) by fat mass and 0 (0%) by lean soft tissue mass. The fat mass in cirrhotic patients was less than in controls, whereas lean soft tissue mass and bone mineral content were not different. Fat depletion was severe in Child-class C patients and with severe ascites. Mid-arm fat area and fat mass showed close correlation (r = 0.85, p < 0.01), but mid-arm muscle area and lean soft tissue mass showed poor correlation (r = 0.32, p < 0.05). CONCLUSION Cirrhotic patients showed lower fat component, with preserved lean soft tissue mass and bone mineral content. In clinical practice, the measurement of mid-arm fat area was useful for the assessment of fat mass.

Background: There are few data about long-term respiratory complications following Middle East Respiratory Syndrome coronavirus (MERS-CoV) infection This study aimed to evaluate respiratory functions and radiologic sequelae according to the severity of infection one year after the patients experienced MERS-CoV infection Methods: A total of 73 patients undergoing MERS-CoV infection during the 2015 MERS outbreak in South Korea were enrolled in this prospective multicenter study Pulmonary function tests and 6-minute walking tests were performed 1 year after infection Radiologic sequelae was defined as fibrosis or atelectasis on chest computer tomography and severe pneumonia was defined as that requiring oxygen therapy Multivariate linear regression tests were used to evaluate the effect of infection severity on respiratory function Results: At the time of MERS-CoV infection, 18 patients had no pneumonia, 35 experienced mild pneumonia, and 20 did severe pneumonia The median age was not different between groups (P = 0 942) Forced vital capacity (FVC) was 102 6%, 94 9%, and 88 7% in the no, mild, and severe pneumonia group, respectively (P = 0 010) and forced expiratory volume in 1 second was 105 3%, 95 7%, and 91 7% (P = 0 057) Diffusing capacity (DLCO) was significantly lower in the severe pneumonia group than in the no or mild pneumonia group (78 3% vs 89 4% or 88 6%, P = 0 035) In multivariate analyses, FVC and DLCO were significantly correlated with infection severity after adjustment with age, sex, underlying lung disease, and smoking There was no difference in the walking distance of 6 minute tests between groups Radiologic sequelae were shown in 18 8%, 65 6%, and 100% in the no, mild, and severe pneumonia group, respectively (P < 0 001) Conclusion: The patients with more severe pneumonia by MERS-CoV had more impaired respiratory function in one year follow-up, which was compatible with radiologic sequelae Disclosures: All authors: No reported disclosures FAU - Il Jun, Kang

Background From May to July 2015, the Republic of Korea experienced the largest outbreak of Middle East respiratory syndrome (MERS) outside the Arabian Peninsula. A total of 186 patients, including 36 deaths, had been diagnosed with MERS-coronavirus (MERS-CoV) infection as of September 30th, 2015. Materials and Methods We obtained information of patients who were confirmed to have MERS-CoV infection. MERS-CoV infection was diagnosed using real-time reverse-transcriptase polymerase chain reaction assay. Results The median age of the patients was 55 years (range, 16 to 86). A total of 55.4% of the patients had one or more coexisting medical conditions. The most common symptom was fever (95.2%). At admission, leukopenia (42.6%), thrombocytopenia (46.6%), and elevation of aspartate aminotransferase (42.7%) were observed. Pneumonia was detected in 68.3% of patients at admission and developed in 80.8% during the disease course. Antiviral agents were used for 74.7% of patients. Mechanical ventilation, extracorporeal membrane oxygenation, and convalescent serum were employed for 24.5%, 7.1%, and 3.8% of patients, respectively. Older age, presence of coexisting medical conditions including diabetes or chronic lung disease, presence of dyspnea, hypotension, and leukocytosis at admission, and the use of mechanical ventilation were revealed to be independent predictors of death. Conclusion The clinical features of MERS-CoV infection in the Republic of Korea were similar to those of previous outbreaks in the Middle East. However, the overall mortality rate (20.4%) was lower than that in previous reports. Enhanced surveillance and active management of patients during the outbreak may have resulted in improved outcomes.

두 개의 서로 다른 조직형의 악성 림프종이 한 사람에게서 발생되는 것은 매우 드물다. 순차적 림프종이란 두 가지 조직형의 림프종이 한 사람에게서 시간차를 두고 발생되는 것을 말한다. 47세 HIV 감염인이 혼합세포형 호지킨 림프종을 진단 받고 ABVD 복합항암화학요법을 시행하였다. 복합항암화학요법 6차 시행 후 복부 컴퓨터 단층촬영에서 여러 개의간 내 병변이 관찰되었으며 경피적 침생검술과 PCR-SSCP 결과 간비장 T-세포 림프종으로 진단되었다. 전신상태 악화로 항암화학요법을 시행하지 못했으며 간비장 T-세포 림프종 진단 3개월 만에 사망하였다. 본 환자는 HIV 감염인에서 호지킨 림프종 발병 후에 간비장 T-세포 림프종이 발병한 순차적 림프종의 국내 첫 사례로 문헌고찰과 함께 보고하는 바이다.

The average life expectancy of human immunodeficiency virus (HIV)-infected patients has improved dramatically following the advent of highly active anti-retroviral therapy. However, this increased life expectancy has led to a greater incidence of non-acquired immune deficiency syndrome related diseases, including cardiovascular diseases and other malignancies. Increased bone fragility is also a significant concern, with the incidence of osteoporosis and osteoporotic fractures 3- and 2-times more likely, respectively, among HIV-infected patients. Bone mineral density screenings for osteoporosis will therefore become more important as the HIV-infected population ages. Here, we describe six cases of osteoporotic fractures in HIV-infected patients in Korea. (Korean J Med 2015;88:236-240)

Patients with human immunodeficiency virus (HIV) infection have a higher burden of seizures, but few studies have examined seizures in HIV-infected individuals in Korea. A retrospective study was conducted to determine the epidemiology and clinical characteristics of seizures in patients with HIV infection. Among a total of 1,141 patients, 34 (3%) had seizures or epilepsy; 4 of these individuals had epilepsy before HIV infection, and the others showed new-onset seizures. Most patients exhibited moderate (200 to 500, n = 13) or low (below 200, n = 16) CD4 counts. The most common seizure etiology was progressive multifocal leukoencephalopathy (n = 14), followed by other HIV-associated central nervous system (CNS) complications (n = 6). Imaging studies revealed brain lesions in 21 patients. A total of 9 patients experienced only one seizure during the follow-up period, and 25 patients experienced multiple seizures or status epilepticus (n = 2). Multiple seizures were more common in patients with brain etiologies (P = 0.019) or epileptiform discharges on EEG (P = 0.032). Most seizures were controlled without anticonvulsants (n = 12) or with a single anticonvulsant (n = 12). Among patients with HIV infection, seizures are significantly more prevalent than in the general population. Most seizures, with the exception of status epilepticus, have a benign clinical course and few complications. Graphical Abstract

Middle East respiratory syndrome (MERS) is an acute infectious disease of the respiratory system caused by the new betacoronavirus (MERS coronavirus, MERS-CoV), which shows high mortality rates. The typical symptoms of MERS are fever, cough, and shortness of breath, and it is often accompanied by pneumonia. The MERS-CoV was introduced to Republic of Korea in May 2015 by a patient returning from Saudi Arabia. The disease spread mostly through hospital infections, and by the time the epidemic ended in August, the total number of confirmed diagnoses was 186, among which 36 patients died. Reflecting the latest evidence for antiviral drugs in the treatment of MERS-CoV infection and the experiences of treating MERS patients in Republic of Korea, these guidelines focus on antiviral drugs to achieve effective treatment of MERS-CoV infections.

열대·아열대 지역 국가를 여행한 후 의사를 방문하게 되는 가장 흔한 원인 중 하나가 발열이다. 최근 질병관리본부자료에 의하면 우리나라 국민의 해외여행 후 감염증은 뎅기열 34.1%, 세균성 이질 24.3%, 말라리아 15.8%의 순이었다. 해외여행지에서 흔히 발생하는 여러 감염병 정보와 여행력에대한 체계적인 문진, 감염원에 대한 노출 정보를 평가하고 신체검사를 시행한다. 열대열 말라리아는 신속히 진단하여 치료를 해야 하는 중증 감염증으로 말초혈액도말검사, 신속진단검사와 PCR 검사로 정확하게 진단할 수 있다. 의료인은열대· 아열대 지역 국가에서 발생하는 감염병에 대한 최신 정보를 습득하여, 해외여행을 계획하고 있는 여행객에게 여러가지 감염병 발생정보의 제공과 예방접종, 말라리아 예방약을 처방하여 안전한 여행이 될 수 있도록 해야 한다.

The anti-inflammatory, antioxidant, and antimicrobial properties of artemisinin derived from water, methanol, ethanol, or acetone extracts of Artemisia annua L. were evaluated. All 4 artemisinin-containing extracts had anti-inflammatory effects. Of these, the acetone extract had the greatest inhibitory effect on lipopolysaccharide-induced nitric oxide (NO), prostaglandin E2 (PGE2), and proinflammatory cytokine (IL-1β , IL-6, and IL-10) production. Antioxidant activity evaluations revealed that the ethanol extract had the highest free radical scavenging activity, (91.0±3.2%), similar to α-tocopherol (99.9%). The extracts had antimicrobial activity against the periodontopathic microorganisms Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum subsp. animalis, Fusobacterium nucleatum subsp. polymorphum, and Prevotella intermedia. This study shows that Artemisia annua L. extracts contain anti-inflammatory, antioxidant, and antimicrobial substances and should be considered for use in pharmaceutical products for the treatment of dental diseases.

Low bone mineral density (BMD) is common in HIV-infected patients. We aimed to describe the prevalence of low BMD and risk factors in Korean HIV-infected patients and to assess the effects of antiretroviral therapy (ART) on BMD. We retrospectively evaluated 224 HIV infected-patients. The prevalence of osteopenia and osteoporosis were 41.5% and 12.9%. These were much higher in 53 patients aged 50 yr and older (52.8% and 34.0%). Older age, lower body mass index, and ART > 3 months were independent risk factors for low BMD. Osteoporosis was more prevalent in patients on the abacavir-based regimen for < 1 yr than ≥ 1 yr; however, it was more prevalent in patients on the zidovudine-based regimen for ≥ 1 yr than < 1 yr (P = 0.017). Osteoporosis in patients on the abacavir-based regimen was more common in the spine than in the femur (P = 0.01). Given such a high prevalence of low BMD, close monitoring of BMD for HIV-infected patients on ART is required. The different prevalence of osteoporosis over time and affected areas between two regimens suggest they may play roles in different mechanisms in bone loss.

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.

Background : Yellow fever (YF) can be prevented through vaccination, but YF vaccination causes adverse events. The increasing number of travelers to YF-endemic areas prompted an investigation of YF vaccination’s adverse events on Koreans. Materials and Methods : From January to December 2007, 318 live-17DD vaccinees at the International Travelers’ Clinic of the National Medical Center were enrolled in this study. Results : The adverse events were evaluated through six telephone interviews of 309 subjects (male: 168, 54.4%) on days 3, 6, 9, 16, 23, and 30 after the administration of the vaccine. There were 106 adverse events in 97 (31.4%) subjects aged 11 months to 70 years (male: 56, 18.1%). Of the 34 (11.0%) subjects who had underlying diseases, 3 (1.0%) reported adverse events (P=0.06). Nineteen (6.1%) of the 72 (23.3%) subjects who concurrently received other vaccines also experienced adverse events (P=0.29). Those who had underlying illnesses and those aged 10 to 19 years reported more frequent adverse events (P=0.06 and 0.14, respectively), but the significance of this finding is uncertain. Most of the adverse events occurred within 10 days after the vaccination and spontaneously subsided. Conclusion : This study shows that most of the YF vaccine’s adverse events are well tolerated and that the vaccine safely protects a vaccinee from YF.

Background :Recently, many Korean people travel abroad where malaria is prevalent. However, in Korea, relatively little is known about compliance of chemoprophylaxis against malaria. This study was performed to determine the factors influencing compliance of chemoprophylaxis against malaria in Korean travelers. Materials and Methods : Face to face interview, telephone interview and e-mail correspondence were performed to 241 people who were prescribed with atovaquone-proguanil at the international travelers' clinic of National Medical Center between February 2007 and October 2007. Results : Total of 55 people out of 235 reported one or more events of adverse reactions after chemoprophylaxis (total 76 events). However, in 38 adverse events the link between chemoprophylaxis and adverse events were very weak. Compliance of malaria chemoprophylaxis with atovaquone-proguanil was 53.9% in the study group. The predictive factors for non-compliance were package tour, travel of business affair and young age group. Conclusions :Compliance of malaria chemoprophylaxis in Korea travelers was low compared with Dutch and French studies. More efforts to increase compliance are needed, especially in travelers on package tour, business travel and people under age 40.

연구배경 : Pressure-controlled ventilation(PCV)은 최근 호흡부전 환자에게서 자주 사용되는 환기방식이다. 이론적으로 PCV은 초기에 높은 기류를 제공하므로 volume-controlled ventilation(VCV)에 비해 최고흡기압이 낮고 가스교환에 이점이 있을 것으로 사료된다. 그러나 PCV에서 최고흡기압이 낮은 것에 대해서는 대부분의 보고가 일치하고 있으나 가스교환에 대해서는 상반된 결과를 보고하고 있다. 따라서 본 연구는 호흡부전 환자에서 PCV과 VCV간의 호흡역학과 가스교환의 비교 및 I : E ratio의 변동에 따른 차이가 있는지를 알아보고자 본 연구를 시행하였다. 방 법 : 호흡부전으로 기계호흡을 받고 있는 9명의 환자를 대상으로 하였다. 각 대상환자에서 흡기산소농도, 일회호흡용적, 호흡수 및 호기말양압은 변화시키지 않고, PCV와 VCV을 번갈아 적용하고 I : E ratio를 1 : 2, 1 : 1.3 및 1.7 : 1로 변화시키면서 기도압과 동맥혈 가스분석, 호기 이산화탄소 농도를 측정하여 PCV과 VCV 간의 호흡역학과 가스교환을 비교하였다. 결 과 : PCV과 VCV 모두에서 I : E ratio를 증가시킴에 따라 평균기도압이 증가하였고, $PaCO_2$ 와 생리적 사강이 감소하였다. 그러나 P(A-a) $O_2$ 는 변하지 않았다. 각각의 I : E ratio 모두에서 최고흡기압은 PCV시 더 낮았으며, 평균기도압은 PCV에서 더 높았다. 그러나 $PaCO_2$ , 생리적 사강 및 P(A-a) $O_2$ 는 PCV과 VCV간의 차이를 보이지 않았다. 결 론 : 동일한 일회호흡용적, 호흡수 및 I : E ratio 상태에서는 두 환기 양식의 차이에 따른 가스교환의 차이가 없었다. 【Background : Pressure-controlled ventilation (PCV) is frequently used recently as the initial mode of mechanical ventilation in the patients with respiratory failure. Theoretically, because of its high initial inspiratory flow, pressure-controlled ventilation has lower peak inspiratory pressure and improved gas exchange than volume-controlled ventilation (VCV). But the data from previous studies showed controversial results about the gas exchange. Moreover, the comparison study between PCV and VCV with various inspiration : expiration time ratios (I : E ratios) is rare. So this study was performed to compare the respiratory mechanics and gas exchange between PCV and VCV with various I : E raitos. Methods : Nine patients receiving mechanical ventilation for respiratory failure were enrolled. They were ventilated by both PCV and VCV with various I : E ratios (1 : 2, 1 : 1.3 and 1.7 : 1). $FiO_2$ , tidal volume, respiratory rate and external positive end-expiratory pressure (PEEP) were kept constant throughout the study. After 20 minutes of each ventilation mode, arterial blood gas, airway pressures, expired $CO_2$ were measured. Results : In both PCV and VCV, as the I : E ratio increased, the mean airway pressure was increased, and $PaCO_2$ and physiologic dead space fraction were decreased. But P(A-a) $O_2$ was not changed. In all three different I : E ratios, peak inspiratory pressure was lower during PCV, and mean airway pressure was higher during PCV. But $PaCO_2$ level, physiologic dead space fraction and P(A-a) $O_2$ were not different between PCV and VCV with three different I : E ratios. Conclusion : There was no difference in gas exchange between PCV and VCV under the same tidal volume, frequency and I : E ratio.】