Perfluoroalkyl substances (PFAS) are widely used in industry and daily life due to their useful properties. They have a long half-life, accumulate in the body, and there is evidence that they are associated with biomarkers of lipid metabolism and liver damage. This may suggest non-alcoholic fatty liver disease (NAFLD) caused by PFAS. However, since there has been no study analyzing the relationship between PFAS and NAFLD in the entire population in Korea. We sought to confirm the relationship between serum PFAS concentration and NAFLD prevalence in Korean adults using the Korean National Environmental Health Survey (KoNEHS) cycle 4.

The incidence of anaplastic large cell lymphoma is 0.25 cases per 100,000 people. It usually causes lymphadenopathy and B symptoms; however, diverse cutaneous manifestations can also be observed. We report a rare case of anaplastic large cell lymphoma of the scalp, which presented similarly to a ruptured epidermal cyst. A 77-year-old woman visited the outpatient clinic complaining of scalp masses that had appeared 2 months before. One week before her visit, she had undergone incision and drainage at a local clinic but showed no improvement. Before surgery, facial magnetic resonance imaging revealed two suspicious ruptured cystic masses. Surgical excision was performed with a 1-cm free margin from the soft mass. Histopathology confirmed anaplastic lymphoma kinase-negative anaplastic large cell lymphoma. After wide excision and skin grafting for wound reconstruction, followed by consultation with a hemato-oncologist and radiation oncologist, chemotherapy was planned to prevent recurrence. Differentiating anaplastic lymphoma kinase-negative anaplastic large cell lymphoma of the scalp from a ruptured epidermal cyst-like mass proved challenging. We recommend considering the possibility of anaplastic large cell lymphoma if an epidermal cyst-like mass does not respond to antibiotics or conventional dressing, as illustrated by our rare case.

Perfluoroalkyl substances (PFAS) are widely used in industry and daily life due to their useful properties. They have a long half-life, accumulate in the body, and there is evidence that they are associated with biomarkers of lipid metabolism and liver damage. This may suggest non-alcoholic fatty liver disease (NAFLD) caused by PFAS. However, since there has been no study analyzing the relationship between PFAS and NAFLD in the entire population in Korea. We sought to confirm the relationship between serum PFAS concentration and NAFLD prevalence in Korean adults using the Korean National Environmental Health Survey (KoNEHS) cycle 4.

The incidence of anaplastic large cell lymphoma is 0.25 cases per 100,000 people. It usually causes lymphadenopathy and B symptoms; however, diverse cutaneous manifestations can also be observed. We report a rare case of anaplastic large cell lymphoma of the scalp, which presented similarly to a ruptured epidermal cyst. A 77-year-old woman visited the outpatient clinic complaining of scalp masses that had appeared 2 months before. One week before her visit, she had undergone incision and drainage at a local clinic but showed no improvement. Before surgery, facial magnetic resonance imaging revealed two suspicious ruptured cystic masses. Surgical excision was performed with a 1-cm free margin from the soft mass. Histopathology confirmed anaplastic lymphoma kinase-negative anaplastic large cell lymphoma. After wide excision and skin grafting for wound reconstruction, followed by consultation with a hemato-oncologist and radiation oncologist, chemotherapy was planned to prevent recurrence. Differentiating anaplastic lymphoma kinase-negative anaplastic large cell lymphoma of the scalp from a ruptured epidermal cyst-like mass proved challenging. We recommend considering the possibility of anaplastic large cell lymphoma if an epidermal cyst-like mass does not respond to antibiotics or conventional dressing, as illustrated by our rare case.

Perfluoroalkyl substances (PFAS) are widely used in industry and daily life due to their useful properties. They have a long half-life, accumulate in the body, and there is evidence that they are associated with biomarkers of lipid metabolism and liver damage. This may suggest non-alcoholic fatty liver disease (NAFLD) caused by PFAS. However, since there has been no study analyzing the relationship between PFAS and NAFLD in the entire population in Korea. We sought to confirm the relationship between serum PFAS concentration and NAFLD prevalence in Korean adults using the Korean National Environmental Health Survey (KoNEHS) cycle 4.

The incidence of anaplastic large cell lymphoma is 0.25 cases per 100,000 people. It usually causes lymphadenopathy and B symptoms; however, diverse cutaneous manifestations can also be observed. We report a rare case of anaplastic large cell lymphoma of the scalp, which presented similarly to a ruptured epidermal cyst. A 77-year-old woman visited the outpatient clinic complaining of scalp masses that had appeared 2 months before. One week before her visit, she had undergone incision and drainage at a local clinic but showed no improvement. Before surgery, facial magnetic resonance imaging revealed two suspicious ruptured cystic masses. Surgical excision was performed with a 1-cm free margin from the soft mass. Histopathology confirmed anaplastic lymphoma kinase-negative anaplastic large cell lymphoma. After wide excision and skin grafting for wound reconstruction, followed by consultation with a hemato-oncologist and radiation oncologist, chemotherapy was planned to prevent recurrence. Differentiating anaplastic lymphoma kinase-negative anaplastic large cell lymphoma of the scalp from a ruptured epidermal cyst-like mass proved challenging. We recommend considering the possibility of anaplastic large cell lymphoma if an epidermal cyst-like mass does not respond to antibiotics or conventional dressing, as illustrated by our rare case.

Background: s/Aims: Reported incidence of extrahepatic bile duct cancer is higher in Asians than in Western populations. Korea, in particular, is one of the countries with the highest incidence rates of extrahepatic bile duct cancer in the world. Although research and innovative therapeutic modalities for extrahepatic bile duct cancer are emerging, clinical guidelines are currently unavailable in Korea. The Korean Society of Hepato-Biliary-Pancreatic Surgery in collaboration with related societies (Korean Pancreatic and Biliary Surgery Society, Korean Society of Abdominal Radiology, Korean Society of Medical Oncology, Korean Society of Radiation Oncology, Korean Society of Pathologists, and Korean Society of Nuclear Medicine) decided to establish clinical guideline for extrahepatic bile duct cancer in June 2021. Methods: Contents of the guidelines were developed through subgroup meetings for each key question and a preliminary draft was finalized through a Clinical Guidelines Committee workshop. Results: In November 2021, the finalized draft was presented for public scrutiny during a formal hearing. Conclusions The extrahepatic guideline committee believed that this guideline could be helpful in the treatment of patients.

Background/Aims: Functional dyspepsia (FD) has long been regarded as a syndrome because its pathophysiology is multifactorial. However, recent reports have provided evidence that changes in the duodenal ecosystem may be the key. This study aimed to identify several gastrointestinal factors and biomarkers associated with FD, specifically changes in the duodenal ecosystem that may be key to understanding its pathophysiology. Methods: In this case-control study, 28 participants (12 with FD and 16 healthy control individuals) were assessed for dietary nutrients, gastrointestinal symptom severity, immunological status of the duodenal mucosa, and microbiome composition from oral, duodenal, and fecal samples. Integrated data were analyzed using immunohistochemistry, real-time polymerase chain reaction, 16S rRNA sequencing, and network analysis. Results: Duodenal mucosal inflammation and impaired expression of tight junction proteins were confirmed in patients with FD. The relative abundance of duodenal Streptococcus (p=0.014) and reductions in stool Butyricicoccus (p=0.047) were confirmed. These changes in the gut microbiota were both correlated with symptom severity. Changes in dietary micronutrients, such as higher intake of valine, were associated with improved intestinal barrier function and microbiota. Conclusions This study emphasizes the relationships among dietary nutrition, oral and gut microbiota, symptoms of FD, impaired function of the duodenal barrier, and inflammation. Assessing low-grade inflammation or increased permeability in the duodenal mucosa, along with changes in the abundance of stool Butyricicoccus, is anticipated to serve as effective biomarkers for enhancing the objectivity of FD diagnosis and monitoring.

Background: Monitoring the oxygenation status is crucial during general anesthesia to ensure patient safety. Although noninvasive pulse oximetry is commonly used to monitor percutaneous oxygen saturation (SpO2), it may not accurately reflect changes in oxygen partial pressure when the latter is excessively high or low. The oxygen reserve index (ORi) provides real-time information about the oxygen reserve status.Case: We present a case of successful management of subglottic stenosis using balloon bronchoscopy in an infant with a left ventricular assist device implantation under ORi monitoring to predict hypoxemia during the surgical procedure. Conclusions Utilizing ORi monitoring during anesthesia for procedures involving apnea in critically ill infants can help predict impending desaturation before a drop in SpO2 occurs, allowing anesthesiologists to effectively anticipate and manage the apnea period. Continuous ORi monitoring offers valuable insights during surgical procedures, especially in infants with compromised respiratory and cardiovascular functions.

Coronavirus disease 2019 (COVID-19) vaccination may non-specifically alter the host immune system. This study aimed to evaluate the effect of COVID-19 vaccination on hepatitis B surface Ag (HBsAg) titer and host immunity in chronic hepatitis B (CHB) patients. Consecutive 2,797 CHB patients who had serial HBsAg measurements during antiviral treatment were included in this study. Changes in the HBsAg levels after COVID-19 vaccination were analyzed. The dynamics of NK cells following COVID-19 vaccination were also examined using serial blood samples collected prospectively from 25 healthy volunteers. Vaccinated CHB patients (n=2,329) had significantly lower HBsAg levels 1–30 days post-vaccination compared to baseline (median, −21.4 IU/ml from baseline), but the levels reverted to baseline by 91–180 days (median, −3.8 IU/ml). The velocity of the HBsAg decline was transiently accelerated within 30 days after vaccination (median velocity: −0.06, −0.39, and −0.04 log 10 IU/ml/year in pre-vaccination period, days 1–30, and days 31–90, respectively). In contrast, unvaccinated patients (n=468) had no change in HBsAg levels. Flow cytometric analysis showed that the frequency of NK cells expressing NKG2A, an NK inhibitory receptor, significantly decreased within 7 days after the first dose of COVID-19 vaccine (median, −13.1% from baseline; p<0.001). The decrease in the frequency of NKG2A + NK cells was observed in the CD56dimCD16+ NK cell population regardless of type of COVID-19 vaccine. COVID-19 vaccination leads to a rapid, transient decline in HBsAg titer and a decrease in the frequency of NKG2A + NK cells.