1.Prevalence of asymptomatic malaria in high- and low-transmission areas of Tanzania: The role of asymptomatic carriers in malaria persistence and the need for targeted surveillance and control efforts
Ernest MAZIGO ; Hojong JUN ; Wang-Jong LEE ; Johnsy Mary LOUIS ; Fadhila FITRIANA ; Jadidan Hada SYAHADA ; Fauzi MUH ; Feng LU ; Md Atique AHMED ; Seok Ho CHA ; Wanjoo CHUN ; Won Sun PARK ; Se Jin LEE ; Sunghun NA ; Joon-Hee HAN ; Nyalali KIJA ; Smart GEODFREY ; Eun-Teak HAN ; Jim TODD ; Alphaxard MANJURANO ; Winifrida KIDIMA ; Jin-Hee HAN
Parasites, Hosts and Diseases 2025;63(1):57-65
As many countries implement different programs aimed at eliminating malaria, attention should be given to asymptomatic carriers that may interrupt the progress. This was a community-based cross-sectional study conducted in Tanzania from December 2022 to July 2023 within 4 villages from each of the 3 regions, Geita and Kigoma, which are high malaria transmission, and Arusha, which is low transmission. Malaria was diagnosed in asymptomatic individuals aged 1 year and older using the malaria rapid diagnostic test and light microscope. A total of 2,365 of 3,489 (67.9%) participants were enrolled from high-transmission villages. The overall prevalence was 25.5% and 15.8% by malaria rapid diagnostic test and light microscope, respectively. Using the respective tools, the prevalence was significantly higher at 35.6% (confidence interval (CI)=23.6–49.9) and 23.1% (CI=16.2–35.1) in the high-transmission regions (Geita and Kigoma) compared with 2.9% (CI=1.1–3.5) and 1.1% (CI=0.7–1.8) in the low-transmission region (Arusha). Children younger than 15 years and males accounted for the greatest proportion of infections. In the study area, the prevalence of asymptomatic cases was higher than that of reported symptomatic cases in health facilities. We hypothesize that these parasite reservoirs may contribute to the persistence of malaria in the country. Therefore, to achieve comprehensive malaria control in the country, the surveillance and screening of asymptomatic malaria cases are vital.
2.New-Onset Neuromyelitis Optica Spectrum Disorder during Pregnancy: A Case Report
So Hee LEE ; Seongheon KIM ; Se Jin LEE ; Sung Hun KIM ; Sunghun NA
Perinatology 2025;36(1):32-36
Neuromyelitis optica spectrum disorder (NMOSD) is a rare inflammatory disease that most often affects the optic nerves and spinal cord. We describe a case of 36-year-old woman presented at 13 weeks of gestation with 4 extremities paresthesia and weakness that had lasted for two months at her first visit to our hospital. She had two previous uncomplicated full-term vaginal deliveries and no significant medical or family history. Spine magnetic resonance imaging (MRI) showed extensive cervical cord lesion and aquaporin-4 antibodies were strongly positive, confirming the diagnosis of NMOSD. Initial management with high-dose corticosteroids and plasmapheresis was done and she showed substantial improvement, but she revisited hospital at 26 weeks of gestational age due to visual disturbance and aggravated weakness. Relapse of NMOSD was confirmed by spine MRI, so rituximab therapy was initiated at 28 weeks of gestational age for prevention of recurrence.The patient showed clinical improvement with no adverse effects and relapse of symptoms. She successfully delivered a healthy male infant at 39 weeks and 3 days of gestational age through uncomplicated vaginal delivery. This case demonstrates successful management of new-onset NMOSD during pregnancy using a multi-modal treatment approach including rituximab.
3.Ectopic Mediastinal Thyroid Successfully Removed by Surgical Excision via Transcervical Approach
Seung Yup SON ; Se Hyeon JIN ; Jong Hwan LEE ; Su Il KIM
Korean Journal of Otolaryngology - Head and Neck Surgery 2025;68(4):168-171
Ectopic thyroid is thyroid tissue found in places other than the anterolateral aspect of the second to fourth tracheal ring. Mediastinal ectopic thyroid is rare and only few cases have been reported. The authors experienced a case of 41-year-old female patient with an anterior neck mass. The patient had mild chest discomfort when breathing with no other symptoms. Imaging studies suggested tumor of thymic tissue origin and surgical excision was done. The mass was successfully removed and histopathologically determined to be thyroid tissue. We hereby report with a review of literature a case of ectopic thyroid found in the mediastinum, which was successfully removed by transcervical incision.
4.Ectopic Mediastinal Thyroid Successfully Removed by Surgical Excision via Transcervical Approach
Seung Yup SON ; Se Hyeon JIN ; Jong Hwan LEE ; Su Il KIM
Korean Journal of Otolaryngology - Head and Neck Surgery 2025;68(4):168-171
Ectopic thyroid is thyroid tissue found in places other than the anterolateral aspect of the second to fourth tracheal ring. Mediastinal ectopic thyroid is rare and only few cases have been reported. The authors experienced a case of 41-year-old female patient with an anterior neck mass. The patient had mild chest discomfort when breathing with no other symptoms. Imaging studies suggested tumor of thymic tissue origin and surgical excision was done. The mass was successfully removed and histopathologically determined to be thyroid tissue. We hereby report with a review of literature a case of ectopic thyroid found in the mediastinum, which was successfully removed by transcervical incision.
5.Primary Merkel cell carcinoma of the salivary gland: a clinicopathologic study of four cases with a review of literature
Gyuheon CHOI ; Joon Seon SONG ; Hee Jin LEE ; Gi Hwan KIM ; Young Ho JUNG ; Yoon Se LEE ; Kyung-Ja CHO
Journal of Pathology and Translational Medicine 2025;59(3):171-179
Background:
Primary Merkel cell carcinoma of the salivary gland is currently not listed in the World Health Organization classification. However, cases of Merkel cell type neuroendocrine carcinomas of the salivary gland with perinuclear cytokeratin 20 positivity have been intermittently reported. We here investigated the clinicopathologic features of additional cases.
Methods:
Data of four cases of Merkel cell type small cell neuroendocrine carcinoma of the salivary gland were retrieved. To confirm the tumors’ primary nature, clinical records and pathologic materials were reviewed. Optimal immunohistochemical staining was performed to support the diagnosis.
Results:
All tumors were located in the parotid gland. Possibilities of metastasis were excluded in all cases through a meticulous clinicopathological review. Tumor histology was consistent with the diagnosis of small cell neuroendocrine carcinoma. Tumors’ immunohistochemical phenotypes were consistent with Merkel cell carcinoma, including Merkel cell polyomavirus large T antigen positivity in two of the four cases.
Conclusions
Merkel cell carcinomas can originate in salivary glands and are partly associated with Merkel cell polyomavirus infection as in cutaneous Merkel cell carcinomas.
6.Characteristics and Prevalence of Sequelae after COVID-19: A Longitudinal Cohort Study
Se Ju LEE ; Yae Jee BAEK ; Su Hwan LEE ; Jung Ho KIM ; Jin Young AHN ; Jooyun KIM ; Ji Hoon JEON ; Hyeri SEOK ; Won Suk CHOI ; Dae Won PARK ; Yunsang CHOI ; Kyoung-Ho SONG ; Eu Suk KIM ; Hong Bin KIM ; Jae-Hoon KO ; Kyong Ran PECK ; Jae-Phil CHOI ; Jun Hyoung KIM ; Hee-Sung KIM ; Hye Won JEONG ; Jun Yong CHOI
Infection and Chemotherapy 2025;57(1):72-80
Background:
The World Health Organization has declared the end of the coronavirus disease 2019 (COVID-19) public health emergency. However, this did not indicate the end of COVID-19. Several months after the infection, numerous patients complain of respiratory or nonspecific symptoms; this condition is called long COVID. Even patients with mild COVID-19 can experience long COVID, thus the burden of long COVID remains considerable. Therefore, we conducted this study to comprehensively analyze the effects of long COVID using multi-faceted assessments.
Materials and Methods:
We conducted a prospective cohort study involving patients diagnosed with COVID-19 between February 2020 and September 2021 in six tertiary hospitals in Korea. Patients were followed up at 1, 3, 6, 12, 18, and 24 months after discharge. Long COVID was defined as the persistence of three or more COVID-19-related symptoms. The primary outcome of this study was the prevalence of long COVID after the period of COVID-19.
Results:
During the study period, 290 patients were enrolled. Among them, 54.5 and 34.6% experienced long COVID within 6 months and after more than 18 months, respectively. Several patients showed abnormal results when tested for post-traumatic stress disorder (17.4%) and anxiety (31.9%) after 18 months. In patients who underwent follow-up chest computed tomography 18 months after COVID-19, abnormal findings remained at 51.9%. Males (odds ratio [OR], 0.17; 95% confidence interval [CI], 0.05–0.53; P=0.004) and elderly (OR, 1.04; 95% CI, 1.00–1.09; P=0.04) showed a significant association with long COVID after 12–18 months in a multivariable logistic regression analysis.
Conclusion
Many patients still showed long COVID after 18 months post SARS-CoV-2 infection. When managing these patients, the assessment of multiple aspects is necessary.
7.Prevalence, Incidence, and Metabolic Characteristics of Young Adults with Type 2 Diabetes Mellitus in South Korea (2010–2020)
Ji Yoon KIM ; Jiyoon LEE ; Joon Ho MOON ; Se Eun PARK ; Seung-Hyun KO ; Sung Hee CHOI ; Nam Hoon KIM
Diabetes & Metabolism Journal 2025;49(2):172-182
Background:
This study aimed to examine trends in the prevalence, incidence, metabolic characteristics, and management of type 2 diabetes mellitus (T2DM) among young adults in South Korea.
Methods:
Young adults with T2DM were defined as individuals aged 19 to 39 years who met the diagnostic criteria for T2DM. Data from the Korean National Health Insurance Service-Customized Database (2010–2020, n=225,497–372,726) were analyzed to evaluate trends in T2DM prevalence, incidence, metabolic profiles, comorbidities, and antidiabetic drug prescription. Additional analyses were performed using the Korea National Health and Nutrition Examination Survey.
Results:
The prevalence of T2DM in young adults significantly increased from 1.02% in 2010 to 2.02% in 2020 (P<0.001), corresponding to 372,726 patients in 2020. Over the same period, the incidence rate remained stable within the range of 0.36% to 0.45%. Prediabetes prevalence steadily increased from 15.53% to 20.92%, affecting 3.87 million individuals in 2020. The proportion of young adults with T2DM who were obese also increased, with 67.8% having a body mass index (BMI) ≥25 kg/m² and 31.6% having a BMI ≥30 kg/m² in 2020. The prevalence of hypertension, dyslipidemia, and fatty liver disease also increased, reaching 34.2%, 79.8%, and 78.9%, respectively, in 2020. Although the overall pharmacological treatment rate remained low, the prescription of antidiabetic medications with weight-reducing properties increased over the study period.
Conclusion
The prevalence of T2DM among young adults in South Korea nearly doubled over the past decade. The strong association with obesity and metabolic comorbidities emphasizes the urgent need for targeted prevention and management strategies tailored to this population.
8.The Role of Direct Oral Anticoagulants in Managing Myeloproliferative Neoplasms Patients
Ji Yun LEE ; Ju-Hyun LEE ; Woochan PARK ; Jeongmin SEO ; Minsu KANG ; Eun Hee JUNG ; Sang-A KIM ; Koung Jin SUH ; Ji-Won KIM ; Se Hyun KIM ; Jeong-Ok LEE ; Jin Won KIM ; Yu Jung KIM ; Keun-Wook LEE ; Jee Hyun KIM ; Soo-Mee BANG
Cancer Research and Treatment 2025;57(2):612-620
Purpose:
Thrombosis and bleeding significantly affect morbidity and mortality in myeloproliferative neoplasms (MPNs). The efficacy and safety of direct oral anticoagulants (DOACs) in MPN patients remain uncertain.
Materials and Methods:
We conducted a large, retrospective, nationwide cohort study using the Korean Health Insurance Review and Assessment Service database from 2010 to 2021.
Results:
Out of the 368 MPN patients included in the final analysis, 62.8% were treated with DOACs for atrial fibrillation (AF), and 37.2% for venous thromboembolism (VTE). The AF group was statistically older with higher CHA2DS2-VASc (congestive heart failure, hypertension, age ≥ 75 years, diabetes mellitus, prior stroke, transient ischemic attack, or thromboembolism, vascular disease, age 65-74 years, sex category [female]) scores compared to the VTE group. Antiplatelet agents were used in 51.1% of cases, and cytoreductive drugs in 79.3%, with hydroxyurea being the most common (64.9%). The median follow-up was 22.3 months, with 1-year cumulative incidence rates of thrombosis and bleeding at 11.1% and 3.7%, respectively. Multivariate analysis identified CHA2DS2-VASc scores ≥ 3 (hazard ratio [HR], 3.48), concomitant antiplatelet use (HR, 2.57), and cytoreduction (HR, 2.20) as significant thrombosis risk factors but found no significant predictors for major bleeding.
Conclusion
Despite the limitations of retrospective data, DOAC treatment in MPN patients seems effective and has an acceptable bleeding risk.
9.Association of TP53 Mutation Status and Sex with Clinical Outcome in Non–Small Cell Lung Cancer Treated with Immune Checkpoint Inhibitors: A Retrospective Cohort Study
Songji CHOI ; Se Hyun KIM ; Sejoon LEE ; Jeongmin SEO ; Minsu KANG ; Eun Hee JUNG ; Sang-A KIM ; Koung Jin SUH ; Ji Yun LEE ; Ji-Won KIM ; Jin Won KIM ; Jeong-Ok LEE ; Yu Jung KIM ; Keun-Wook LEE ; Jee Hyun KIM ; Soo-Mee BANG ; Jong Seok LEE
Cancer Research and Treatment 2025;57(1):70-82
Purpose:
Some studies suggest that TP53 mutations are associated with the response to immune checkpoint inhibitors (ICI) in patients with non–small cell lung cancer (NSCLC) and also contribute to sex disparities in several cancers. Thus, we hypothesized that TP53 mutations might serve as sex-dependent genomic biomarkers of ICI treatment response in patients with NSCLC.
Materials and Methods:
Clinical data of 100 patients with metastatic NSCLC treated with ICI monotherapy at Seoul National University Bundang Hospital (SNUBH) were retrospectively reviewed. Genomic and clinical datasets of The Cancer Genome Atlas and an ICI-treated lung cancer cohort (cBioPortal) were also analyzed.
Results:
In SNUBH cohort, no statistically significant difference was observed in the median progression-free survival (PFS) according to TP53 mutation status (p=0.930); however, female patients with TP53 mutations (MT) had a significantly prolonged median PFS compared to wild-type (WT) (6.1 months in TP53 MT vs. 2.6 months in TP53 WT; p=0.021). Programmed death-ligand 1 (PD-L1) high (≥ 50%) expression was significantly enriched in female patients with TP53 MT (p=0.005). The analysis from publicly available dataset also revealed that females with NSCLC with TP53 MT showed significantly longer PFS than those with TP53 WT (p < 0.001). In The Cancer Genome Atlas analysis, expression of immune-related genes, and tumor mutation burden score in TP53 MT females were higher than in males without TP53 MT.
Conclusion
Female patients with NSCLC with TP53 mutations had high PD-L1 expression and showed favorable clinical outcomes following ICI therapy, suggesting a need for further research to explore the role of TP53 mutations for sex disparities in response to ICI therapy.
10.Safety and efficacy of HK-660S in patients with primary sclerosing cholangitis: A randomized double-blind phase 2a trial
Woo Hyun PAIK ; Joo Kyung PARK ; Moon Jae CHUNG ; Gunn HUH ; Ce Hwan PARK ; Sang Hyub LEE ; Heon Se JEONG ; Hee Jin KIM ; Do Hyun PARK
Clinical and Molecular Hepatology 2025;31(1):119-130
Background/Aims:
A clinical unmet need persists for medications capable of modulating the progression of primary sclerosing cholangitis (PSC). This study aimed to assess the clinical feasibility of HK-660S (beta-lapachone) in PSC.
Methods:
In this multicenter, randomized, double-blind, placebo-controlled, parallel-group phase 2 trial, participants were assigned in a 2:1 ratio to receive either 100 mg of HK-660S or a placebo twice daily for 12 weeks. The primary outcomes were the reduction in serum alkaline phosphatase (ALP) levels and the percentage of participants showing improvements in PSC severity, as determined by magnetic resonance cholangiopancreatography with the Anali score. Secondary endpoints included changes in liver stiffness and adverse events.
Results:
The analysis included 21 patients, 15 receiving HK-660S, and six receiving a placebo. Improvements in the Anali score were observed in 13.3% of the HK-660S group, with no improvements in the placebo group. HK-660S treatment resulted in a 15.2% reduction in mean ALP levels, compared to a 6.6% reduction in the placebo group. A stratified ad-hoc analysis based on baseline ALP levels showed a statistically significant response in the HK-660S group among those with ALP levels greater than twice the upper limit of normal, with a 50% responder rate (p=0.05). Additionally, 26.7% of the HK-660S group showed improvements in the enhanced liver fibrosis score, with no improvements in the placebo group. HK-660S was generally well tolerated.
Conclusions
HK-660S is well tolerated among patients with PSC and may improve bile duct strictures, decrease serum ALP levels, and reduce liver fibrosis (cris.nih.go.kr, Number KCT0006590).

Result Analysis
Print
Save
E-mail