Concurrent advancements in imaging and genomic biomarkers have created opportunities to identify non-invasive imaging surrogates of molecular phenotypes. In order to develop such imaging surrogates radiomics and radiogenomics/imaging genomics will be necessary; there has been consistent progress in these fields for primary liver cancers. In this article we evaluate the current status of the field specifically with regards to hepatocellular carcinoma and intrahepatic cholangiocarcinoma, highlighting some of the up and coming results that were presented at the annual Radiological Society of North America Conference in 2017. There are an increasing number of studies in this area with a bias towards quantitative feature measurement, which is expected to benefit reproducibility of the findings and portends well for the future development of biomarkers for diagnosis, prognosis, and treatment response assessment. We review some of the advancements and look forward to some of the exciting future applications that are anticipated as the field develops.
Bias (Epidemiology) ; Biomarkers ; Carcinoma, Hepatocellular ; Cholangiocarcinoma ; Diagnosis ; Genomics ; Liver Neoplasms ; Liver ; North America ; Phenotype ; Prognosis

Clostridium difficile, an anaerobic toxigenic bacterium, causes a severe infectious colitis that leads to significant morbidity and mortality worldwide. Both enhanced bacterial toxins and diminished host immune response contribute to symptomatic disease. C. difficile has been a well-established pathogen in North America and Europe for decades, but is just emerging in Asia. This article reviews the epidemiology, microbiology, pathophysiology, and clinical management of C. difficile. Prompt recognition of C. difficile is necessary to implement appropriate infection control practices.
Asia/epidemiology ; Clostridium Infections/*diagnosis/epidemiology/microbiology/*therapy ; Clostridium difficile/genetics/*pathogenicity ; Europe/epidemiology ; Global Health ; Humans ; North America/epidemiology

OBJECTIVE: Atopic dermatitis is a chronically relapsing inflammatory skin disease. However, little is known about the prevalence of atopic dermatitis outside of North America and Europe. We evaluated the nationwide prevalence of atopic dermatitis with the comparison of prevalence between 1995 and 2000, and between Seoul and provincial cities in Korea. We also evaluated the risk factors for atopic dermatitis. METHODS: A cross-sectional ISAAC based questionnaire survey was conducted on random samples of schoolchildren (6 to 15 year olds) in 1995 and 2000. And kindergarten children (5 year olds) were surveyed in 2003, throughout South Korea. RESULTS: The lifetime and last twelve months prevalence of atopic dermatitis in Korean school-aged children was increased from 1995 to 2000. The twelve-month prevalence of atopic dermatitis was higher in Seoul than in other provincial cities in 1995, but the prevalence of atopic dermatitis in Seoul and Provincial Centers became similar in 2000. CONCLUSION: The prevalence of atopic dermatitis in Korean school-aged children was increased from 1995 to 2000. The further evaluations that include objective examination are necessary to confirm these outcomes because the environmental and risk factors may be different among the countries according to their life styles.
Child* ; Dermatitis, Atopic* ; Epidemiology ; Europe ; Humans ; Korea* ; Life Style ; North America ; Prevalence ; Surveys and Questionnaires ; Risk Factors ; Seoul ; Skin Diseases

BACKGROUND: Increasing rates of Clostridium difficile infection (CDI) have been reported mainly in Europe and North America; however, only limited reports have originated in Korea. The current epidemiology of CDI in the community could help to understand the outpatient healthcare environment and to extend infection control measures to outpatient settings. METHODS: C. difficile isolates in NHIS Ilsan Hospital from 2012 to 2014 were included in this study. Clinical characteristics, acquisition types, and previous antimicrobial therapy were obtained via Electronic Medical Records. C. difficile culture was performed only in unformed stool. Toxin was positive by enzyme-linked fluorescent immunoassay (ELFA) in 247 specimens. In addition, toxin B and binary toxin gene were detected by PCR in 57 specimens. CDI was defined by toxigenic C. difficile isolation in unformed stool. RESULTS: In the previous 3 years, 251 unduplicated C. difficile cases have been detected; 168 healthcare facility- associated hospital onset (HCFA-HO), 45 healthcare facility-associated community onset (HCFA-CO), and 38 community-associated (CA). Toxin positive rates by ELFA for toxin A&B were HCFA-HO 50.6% (84/166), HCFA-CO 41.9% (18/43), and CA 42.1% (16/38). Toxin positive rate by PCR for tcdB were HCFA-HO 62.9% (22/35), HCFA-CO 69.2% (9/13), and CA 100% (9/9). No binary toxin (cdtA/cdtB) was detected in 57 cases. CONCLUSION: Community-associated CDI may be underestimated in Goyang province, Korea, especially by commonly used ELFA toxin assay. The spread of community-associated CDI should be recognized as an increasing burden of public health.
Clostridium difficile* ; Clostridium* ; Community-Acquired Infections ; Delivery of Health Care ; Electronic Health Records ; Epidemiology ; Europe ; Humans ; Immunoassay ; Infection Control ; Korea ; North America ; Outpatients ; Polymerase Chain Reaction ; Public Health*

BACKGROUND: Phylogenetic analysis was used to determine the subtype and the probable source of transmission of human immunodeficiency virus type 1 (HIV-1). The HIV-1 is an RNA virus characterized by extensive genetic variation. To determine the extent of HIV-1 genetic variation, HIV-1 envelope V3 domain structures were analyzed and compared. In this study, we analyzed phylogenetic relationships and the subtype of Korean isolates to help the epidemiological study of HIV-1 infection. METHODS: Peripheral blood mononuclear cells were collected from eight patients with AIDS. HIV-1 proviral DNA was directly amplified directly by polymerase chain reaction (PCR). V3 domain nucleotide sequences were determined using a direct sequencing method with PCR products. Phylogenetic analysis of V3 domain nucleotide sequences was performed comparing with previously documented HIV-1 strains. RESULTS: Six V3 loop sequences were obtained from eight HIV-1 infected patients. All of six HIV-1 strains were classified as subtype B by phylogenetic analysis of the V3 region. The distances between strains varied from 11.5% to 22.9% (mean; 15.9%), showing six strains were not related each other. CONCLUSIONS: Six HIV-1 strains belong to subtype B, which is the prevalent type in North America, Europe, and Japan. Molecular epidemiological data supported the transmission of HIV-1 to Korea from these areas. Phylogenetic analysis revealed the absence of closely related strains in these isolates. Direct sequencing of V3 loop DNA woul d be a useful tool to determine the subgroup and the route of transmission of HIV-1.
Base Sequence* ; DNA* ; Europe ; Genetic Variation ; HIV-1* ; Humans ; Japan ; Korea ; Molecular Epidemiology ; North America ; Polymerase Chain Reaction ; RNA Viruses ; Sequence Analysis, DNA*

Varicella, which is mostly a benign disease, but also can cause considerable health burden in the community, can be prevented by immunization with live attenuated varicella vaccine. Higher uptake of varicella vaccine by universal immunization in North America has apparently been associated with decline in the number of reported cases of varicella, varicella-related hospitalizations, and the number of deaths caused by complications of varicella. On the contrary, there has been some reluctance in endorsing varicella vaccine for universal immunization in most of European countries. Concerns include unanticipated outbreaks of varicella among vaccine recipients, risk of varicella among unvaccinated adults, risk of herpes zoster among vaccinees as well as unvaccinees. Recently developed measles, mumps, rubella, and varicella combination vaccine and herpes zoster vaccine that may be licensed in the upcoming years may be the solution for varicella vaccine to be utilized in a greater scale. In Korea several varicella vaccine products have been utilized since late 1980. The adoption of varicella vaccine for universal immunization since 2005 along with the changing view in varicella prevention strategy mandates more studies for immunogenecity and efficacy of varicella vaccines as well as more surveillance to delineate the changes in epidemiology of varicella in Korea.
Adult ; Chickenpox Vaccine ; Chickenpox* ; Disease Outbreaks ; Epidemiology ; Herpes Zoster ; Herpes Zoster Vaccine ; Hospitalization ; Humans ; Immunization ; Korea ; Measles ; Mumps ; North America ; Rubella ; Vaccination* ; Vaccines

Invasive cancer of the cervix is considered a preventable disease because it has a long preinvasive state, cervical cytology screening programs are currently available, and the treatment of pre-invasive lesions is effective. Cancer of the cervix is the second most common cancer among women worldwide, with an estimated 493,000 new cases and 274,000 deaths in 2002. The highest incidence rates are observed in sub-Saharan Africa, Melanesia, Latin America and the Caribbean, South-Central Asia, and South East Asia. In Korea, cervical cancer is the fifth most common cancer among women with over 3,000 new cases every year. Age-standardized incidence rate (ASR) is 15.5 per 100,000, which is lower than those in developing countries but higher than in western countries such as Europe and North America. The patients' mean parity is 2.59, and the range of age in peak incidence is 40~49 years (29.8%), followed by 50~59 years (21.9%). As the age goes on, more advanced stage cancer is frequent. Squamous cell carcinoma is the most common cell type, and adenocarcinoma is more frequent among those under 60 years old. Operation (56.0%) is the major treatment modality under stage IIa, and concurrent chemoradiation (31.6%) is the major treatment over stage IIb. The 5year survival rate is 73.9%. It is generally thought that human papillomavirus (HPV) test and HPV vaccine might play an important role in lowering the incidence of cervical cancer, and continuous epidemiologic studies will support its usefulness and efficacy.
Adenocarcinoma ; Africa South of the Sahara ; Asia ; Carcinoma, Squamous Cell ; Caribbean Region ; Developing Countries ; Epidemiologic Studies ; Epidemiology* ; Europe ; Far East ; Female ; Humans ; Incidence ; Korea ; Latin America ; Mass Screening ; Melanesia ; Middle Aged ; North America ; Parity ; Survival Rate ; Uterine Cervical Neoplasms*

The incidence of colorectal disease in Korea has been increasing along with the westernitation of the lifestyle. More hemorrhoidectomy and anal surgery have been done than ever. Dynamic graciloplasty, artificial bowel sphincter, and sacral nerve stimulation are done to manage anal incontinence. Constipation and irritable bowel syndrome are popular these days. However, there are few effective definite treatments for them. Ulcerative colitis develops in older age groups than in western countries, but Crohn's disease occurs in the same ages as in western countries. The prevalence of inflammatory bowel disease in Korea was 1/10 in ulcerative colitis and 1/20 in Crohn's disease, compared with North America, however, it increases rapidly. The incidence of colorectal cancer was 25.2 per 100,000 in male and 15.9 in female. The relative frequency of colorectal cancer is 10.5% of all sites, and colorectum is the 4th frequent site of cancers following stomach, lung, and liver. The five-year suvival rate of colorectal cancer in Korea was 49.4%. The management of anorectal disease should be based on medical evidence.
Anal Canal* ; Colitis, Ulcerative ; Colon ; Colorectal Neoplasms ; Constipation ; Crohn Disease ; Epidemiology* ; Female ; Hemorrhoidectomy ; Humans ; Incidence ; Inflammatory Bowel Diseases ; Irritable Bowel Syndrome ; Korea ; Life Style ; Liver ; Lung ; Male ; North America ; Prevalence ; Rectum ; Stomach