Complement component 3 glomerulonephritis (C3GN) is a rare kidney disease characterized by complement dysregulation that results in prominent complement component 3 (C3) deposition in the kidneys. The clinical course of C3GN varies from mild hematuria to progressive chronic kidney disease. In most patients, C3GN is driven by acquired factors, namely, autoantibodies that target C3 or C5 convertases. Genetic variations in complement-related genes are less frequent. We report the case of a 9-yearold Korean boy who presented with microscopic hematuria and a persistently low C3 level and had biopsy findings of C3GN, with the presence of a C3 gene mutation: a frameshift mutation associated with C3 deficiency. However, the patient did not exhibit any other symptoms of complement deficiency. Direct DNA sequencing of his family members revealed the same genetic mutation in his father and older brother. This case report is significant because there are very few such reports worldwide concerning gene mutations related to C3 deficiency to be discovered in patients with C3GN. Explaining C3GN pathogenesis is challenging; therefore, additional research is required in the future.

OBJECTIVES: We estimated the population prevalence of antibodies to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), including unreported infections, through a Korea Seroprevalence Study of Monitoring of SARS-CoV-2 Antibody Retention and Transmission (K-SEROSMART) in 258 communities throughout Korea. METHODS: In August 2022, a survey was conducted among 10,000 household members aged 5 years and older, in households selected through two stage probability random sampling. During face-to-face household interviews, participants self-reported their health status, COVID-19 diagnosis and vaccination history, and general characteristics. Subsequently, participants visited a community health center or medical clinic for blood sampling. Blood samples were analyzed for the presence of antibodies to spike proteins (anti-S) and antibodies to nucleocapsid proteins (anti-N) SARS-CoV-2 proteins using an electrochemiluminescence immunoassay. To estimate the population prevalence, the PROC SURVEYMEANS statistical procedure was employed, with weighting to reflect demographic data from July 2022. RESULTS: In total, 9,945 individuals from 5,041 households were surveyed across 258 communities, representing all basic local governments in Korea. The overall population-adjusted prevalence rates of anti-S and anti-N were 97.6% and 57.1%, respectively. Since the Korea Disease Control and Prevention Agency has reported a cumulative incidence of confirmed cases of 37.8% through July 31, 2022, the proportion of unreported infections among all COVID-19 infection was suggested to be 33.9%. CONCLUSIONS The K-SEROSMART represents the first nationwide, community-based seroepidemiologic survey of COVID-19, confirming that most individuals possess antibodies to SARS-CoV-2 and that a significant number of unreported cases existed. Furthermore, this study lays the foundation for a surveillance system to continuously monitor transmission at the community level and the response to COVID-19.

Plasmodium vivax exhibits dormant liver-stage parasites, called hypnozoites, which can cause relapse of malaria. The only drug currently used for eliminating hypnozoites is primaquine. The antimalarial properties of primaquine are dependent on the production of oxidized metabolites by the cytochrome P450 isoenzyme 2D6 (CYP2D6). Reduced primaquine metabolism may be related to P. vivax relapses. We describe a case of 4 episodes of recurrence of vivax malaria in a patient with decreased CYP2D6 function. The patient was 52-year-old male with body weight of 52 kg. He received total gastrectomy and splenectomy 7 months before the first episode and was under chemotherapy for the gastric cancer. The first episode occurred in March 2019 and each episode had intervals of 34, 41, and 97 days, respectively. At the first and second episodes, primaquine was administered as 15 mg for 14 days. The primaquine dose was increased with 30 mg for 14 days at the third and fourth episodes. Seven gene sequences of P. vivax were analyzed and revealed totally identical for all the 4 samples. The CYP2D6 genotype was analyzed and intermediate metabolizer phenotype with decreased function was identified.

Objective: To investigate long-term and serial functional outcomes in ischemic stroke patients without diabetes with post-stroke hyperglycemia. Methods: The Korean Stroke Cohort for Functioning and Rehabilitation (KOSCO) is a large, multi-center, prospective cohort study of stroke patients admitted to participating hospitals in nine areas of Korea. From KOSCO, ischemic stroke patients without diabetes were recruited and divided into two groups: patients without diabetes without (n=779) and with post-stroke hyperglycemia (n=223). Post-stroke hyperglycemia was defined as a glucose level >8 mmol/L. Functional assessments were performed 7 days and 3, 6, and 12 months after stroke onset. Results: There were no significant differences in baseline characteristics between the groups, except in the age of onset and smoking. Analysis of the linear correlation between the initial National Institutes of Health Stroke Scale (NIHSS) score and glucose level showed no significant difference. Among our functional assessments, NIHSS, Fugl-Meyer Assessment (affected side), Functional Ambulatory Category, modified Rankin Scale, and Korean Mini-Mental State Examination (K-MMSE) showed statistically significant improvements in each group. All functional improvements except K-MMSE were significantly higher in patients without post-stroke hyperglycemia at 7 days and 3, 6, and 12 months. Conclusion The glucose level of ischemic stroke patients without diabetes had no significant correlation with the initial NIHSS score. The long-term effects of stress hyperglycemia showed worse functional outcomes in ischemic stroke patients without diabetes with post-stroke hyperglycemia.

Background: The clinical features of pediatric rhabdomyolysis differ from those of the adults with rhabdomyolysis; however, multicenter studies are lacking. This study aimed to investigate the characteristics of pediatric rhabdomyolysis and reveal the risk factors for acute kidney injury (AKI) in such cases. Methods: This retrospective study analyzed the medical records of children and adolescents diagnosed with rhabdomyolysis at 23 hospitals in South Korea between January 2007 and December 2016. Results: Among 880 patients, those aged 3 to 5 years old composed the largest subgroup (19.4%), and all age subgroups were predominantly male. The incidence of AKI was 11.3%. Neurological disorders (53%) and infection (44%) were the most common underlying disorder and cause of rhabdomyolysis, respectively. The median age at diagnosis in the AKI subgroup was older than that in the non-AKI subgroup (12.2 years vs. 8.0 years). There were no significant differences in body mass index, myalgia, dark-colored urine, or the number of causal factors between the two AKI-status subgroups. The multivariate logistic regression model indicated that the following factors were independently associated with AKI: multiorgan failure, presence of an underlying disorder, strong positive urine occult blood, increased aspartate aminotransferase and uric acid levels, and reduced calcium levels. Conclusions Our study revealed characteristic clinical and laboratory features of rhabdomyolysis in a Korean pediatric population and highlighted the risk factors for AKI in these cases. Our findings will contribute to a greater understanding of pediatric rhabdomyolysis and may enable early intervention against rhabdomyolysis-induced AKI.

The objective of this study was to investigate factors affecting the return home one year after a stroke. The subjects of this study consisted of patients who participated in a large-scale multi-objective cohort study of initial stage stroke patients who were admitted to 9 representative hospitals in Korea. We analyzed the distribution of the subjects who had experienced stroke a year earlier by distinguishing the group who returned home and the other group that was hospitalized in rehabilitation hospitals. Based on this distribution, we evaluated the demographic, environmental, clinical, and psychological factors that can affect the return home. Overall, there were 464 subjects in the ‘Return home’ group and 99 subjects in the ‘Rehabilitation hospitalization’ group. job status, inconvenient housing structures, residential types, diagnosis, Functional Ambulation Categories, modified Rankin Scale, Korea-Modified Barthel Index, Function Independence Measure, Fugl-Meyer Assessment, Korean version of Mini-Mental State Examination, Korean version of Frenchay Aphasia Screening Test, Psychosocial Well-being Index-Short Form, Geriatric Depression Scale-Short Form, EuroQol-five Dimensional showed a significant difference between the 2 groups one year after the stroke. The factors affecting the return home one year after a stroke include functional status, activities of daily living, cognition, depression, stress, quality of life, job status. It is expected that factors affecting the rehabilitation of patients with stroke can be considered as basic data for establishing rehabilitation goals and treatment plans.

The aim of this study is to investigate the changes in functional independence and their associated factors during the first 6 months to 1 year after stroke onset. This study is the interim results of the Korean Stroke Cohort for Functioning and Rehabilitation. A total of 1,011 participants were included and classified into 3 subgroups according to changes in the Korean version of Modified Barthel Index (K-MBI) scores that occurred between 6 months to 1 year after stroke onset: the improved group (IG), with scores that increased 5 points or more; the stationary group (SG), with the K-MBI score changes ranging from −4 to +4 points; and the declined group (DG), with the K-MBI scores that decreased 5 points or more. Ordinal logistic regression analyses were used to assess the factors influencing changes in the K-MBI score. Among 1,011 patient, 436 patients (43.1%), 398 patients (39.4%) and 117 patients (17.5%) were classified into the IG, SG, and DG, respectively. Obesity and Geriatric Depression Scale score were significant influencing factors for changes in the K-MBI scores. Obesity showed a positive influence on the K-MBI score, while depression showed a negative influence.

Valuable natural compounds produced by a variety of microorganisms can be used as lead molecules for development of new agrochemicals. Furthermore, high-throughput in vitro screening systems with specific modes of action can increase the probability of discovery of new fungicides. In the current study, a rapid assay tested with various microbes was developed to determine the degree of respiratory inhibition of Saccharomyces cerevisiae in two different liquid media, YG (containing a fermentable carbon source) and NFYG (containing a non-fermentable carbon source). Based on this system, we screened 100 fungal isolates that were classified into basidiomycetes, to find microbial secondary metabolites that act as respiratory inhibitors. Consequently, of the 100 fungal species tested, the culture broth of an IUM04881 isolate inhibited growth of S. cerevisiae in NFYG medium, but not in YG medium. The result is comparable to that from treatment with kresoxim-methyl used as a control, suggesting that the culture broth of IUM04881 isolate might contain active compounds showing the inhibition activity for respiratory chain. Based on the assay developed in this study and spectroscopic analysis, we isolated and identified an antifungal compound (-)-oudemansin A from culture broth of IUM04881 that is identified as Oudemansiella venosolamellata. This is the first report that (-)-oudemansin A is identified from O. venosolamellata in Korea. Taken together, the development of this assay will accelerate efforts to find and identify natural respiratory inhibitors from various microbes.

The objective of this study was to investigate factors affecting the return home one year after a stroke. The subjects of this study consisted of patients who participated in a large-scale multi-objective cohort study of initial stage stroke patients who were admitted to 9 representative hospitals in Korea. We analyzed the distribution of the subjects who had experienced stroke a year earlier by distinguishing the group who returned home and the other group that was hospitalized in rehabilitation hospitals. Based on this distribution, we evaluated the demographic, environmental, clinical, and psychological factors that can affect the return home. Overall, there were 464 subjects in the ‘Return home’ group and 99 subjects in the ‘Rehabilitation hospitalization’ group. job status, inconvenient housing structures, residential types, diagnosis, Functional Ambulation Categories, modified Rankin Scale, Korea-Modified Barthel Index, Function Independence Measure, Fugl-Meyer Assessment, Korean version of Mini-Mental State Examination, Korean version of Frenchay Aphasia Screening Test, Psychosocial Well-being Index-Short Form, Geriatric Depression Scale-Short Form, EuroQol-five Dimensional showed a significant difference between the 2 groups one year after the stroke. The factors affecting the return home one year after a stroke include functional status, activities of daily living, cognition, depression, stress, quality of life, job status. It is expected that factors affecting the rehabilitation of patients with stroke can be considered as basic data for establishing rehabilitation goals and treatment plans.
Activities of Daily Living ; Aphasia ; Cognition ; Cohort Studies ; Depression ; Diagnosis ; Housing ; Humans ; Korea ; Mass Screening ; Patient Discharge ; Psychology ; Quality of Life ; Rehabilitation ; Stroke ; Walking