Background: and Purpose To determine the clinical phenotypes, relapse timing, treatment responses, and outcomes of children with relapsing myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD). Methods: We collected the demographic, clinical, laboratory, and radiological data of patients aged <18 years who had been diagnosed with MOGAD at Seoul National University Children’s Hospital between January 2010 and January 2022; 100 were identified as positive for MOG antibodies, 43 of whom experienced relapse. Results: The median age at onset was 7 years (range 2–16 years). The median number of relapses was 2 (range 1–8), and patients were followed up for a median of 65 months (range 5–214 months). The first relapse was experienced before 3 months from onset by 15 patients (34.9%). The most-common initial phenotypes were acute disseminated encephalomyelitis (n=17, 39.5%) and optic neuritis (ON; n=11, 25.6%). The most-common relapse phenotypes were neuromyelitis optica spectrum disorder (n=9, 20.9%), relapsing ON (n=6, 14.0%), and multiphasic disseminated encephalomyelitis (n=6, 14.0%). Many of the patients (n=18, 41.9%) were not specifically categorized. A high proportion of these patients had non-acute disseminated encephalomyelitis encephalitis. Atypical phenotypes such as prolonged fever or hemiplegic migraine-like episodes were also noted. Mycophenolate mofetil and cyclic immunoglobulin treatment significantly reduced the annual relapse rates. Conclusions Our 43 pediatric patients with relapsing MOGAD showed a tendency toward early relapse and various relapse phenotypes. The overall prognoses of these patients were good regardless of phenotype or response to second-line immunosuppressant treatment.

Background: and Purpose To determine the clinical phenotypes, relapse timing, treatment responses, and outcomes of children with relapsing myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD). Methods: We collected the demographic, clinical, laboratory, and radiological data of patients aged <18 years who had been diagnosed with MOGAD at Seoul National University Children’s Hospital between January 2010 and January 2022; 100 were identified as positive for MOG antibodies, 43 of whom experienced relapse. Results: The median age at onset was 7 years (range 2–16 years). The median number of relapses was 2 (range 1–8), and patients were followed up for a median of 65 months (range 5–214 months). The first relapse was experienced before 3 months from onset by 15 patients (34.9%). The most-common initial phenotypes were acute disseminated encephalomyelitis (n=17, 39.5%) and optic neuritis (ON; n=11, 25.6%). The most-common relapse phenotypes were neuromyelitis optica spectrum disorder (n=9, 20.9%), relapsing ON (n=6, 14.0%), and multiphasic disseminated encephalomyelitis (n=6, 14.0%). Many of the patients (n=18, 41.9%) were not specifically categorized. A high proportion of these patients had non-acute disseminated encephalomyelitis encephalitis. Atypical phenotypes such as prolonged fever or hemiplegic migraine-like episodes were also noted. Mycophenolate mofetil and cyclic immunoglobulin treatment significantly reduced the annual relapse rates. Conclusions Our 43 pediatric patients with relapsing MOGAD showed a tendency toward early relapse and various relapse phenotypes. The overall prognoses of these patients were good regardless of phenotype or response to second-line immunosuppressant treatment.

Background: and Purpose To determine the clinical phenotypes, relapse timing, treatment responses, and outcomes of children with relapsing myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD). Methods: We collected the demographic, clinical, laboratory, and radiological data of patients aged <18 years who had been diagnosed with MOGAD at Seoul National University Children’s Hospital between January 2010 and January 2022; 100 were identified as positive for MOG antibodies, 43 of whom experienced relapse. Results: The median age at onset was 7 years (range 2–16 years). The median number of relapses was 2 (range 1–8), and patients were followed up for a median of 65 months (range 5–214 months). The first relapse was experienced before 3 months from onset by 15 patients (34.9%). The most-common initial phenotypes were acute disseminated encephalomyelitis (n=17, 39.5%) and optic neuritis (ON; n=11, 25.6%). The most-common relapse phenotypes were neuromyelitis optica spectrum disorder (n=9, 20.9%), relapsing ON (n=6, 14.0%), and multiphasic disseminated encephalomyelitis (n=6, 14.0%). Many of the patients (n=18, 41.9%) were not specifically categorized. A high proportion of these patients had non-acute disseminated encephalomyelitis encephalitis. Atypical phenotypes such as prolonged fever or hemiplegic migraine-like episodes were also noted. Mycophenolate mofetil and cyclic immunoglobulin treatment significantly reduced the annual relapse rates. Conclusions Our 43 pediatric patients with relapsing MOGAD showed a tendency toward early relapse and various relapse phenotypes. The overall prognoses of these patients were good regardless of phenotype or response to second-line immunosuppressant treatment.

Pediatric differentiated thyroid cancers (DTCs), mostly papillary thyroid cancer (PTC, 80-90%), are diagnosed at more advanced stages with larger tumor sizes and higher rates of locoregional and/or lung metastasis. Despite the higher recurrence rates of pediatric cancers than of adult thyroid cancers, pediatric patients demonstrate a lower mortality rate and more favorable prognosis. Considering the more advanced stage at diagnosis in pediatric patients, preoperative evaluation is crucial to determine the extent of surgery required. Furthermore, if hereditary tumor syndrome is suspected, genetic testing is required. Recommendations for pediatric DTCs focus on the surgical principles, radioiodine therapy according to the postoperative risk level, treatment and follow-up of recurrent or persistent diseases, and treatment of patients with radioiodine-refractory PTCs on the basis of genetic drivers that are unique to pediatric patients.

Differentiated thyroid cancer demonstrates a wide range of clinical presentations, from very indolent cases to those with an aggressive prognosis. Therefore, diagnosing and treating each cancer appropriately based on its risk status is important. The Korean Thyroid Association (KTA) has provided and amended the clinical guidelines for thyroid cancer management since 2007. The main changes in this revised 2024 guideline include 1) individualization of surgical extent according to pathological tests and clinical findings, 2) application of active surveillance in low-risk papillary thyroid microcarcinoma, 3) indications for minimally invasive surgery, 4) adoption of World Health Organization pathological diagnostic criteria and definition of terminology in Korean, 5) update on literature evidence of recurrence risk for initial risk stratification, 6) addition of the role of molecular testing, 7) addition of definition of initial risk stratification and targeting thyroid stimulating hormone (TSH) concentrations according to ongoing risk stratification (ORS), 8) addition of treatment of perioperative hypoparathyroidism, 9) update on systemic chemotherapy, and 10) addition of treatment for pediatric patients with thyroid cancer.

Purpose: The treatment of male breast cancer (MBC) has been extrapolated from female breast cancer (FBC) because of its rarity despite their different clinicopathologic characteristics. We aimed to investigate the distribution of intrinsic subtypes based on immunohistochemistry, their clinical impact, and treatment pattern in clinical practice through a multicenter study in Korea. Materials and Methods: We retrospectively analyzed clinical data of 248 MBC patients from 18 institutions across the country from January 1995 to July 2016. Results: The median age of MBC patients was 63 years (range, 25 to 102 years). Among 148 intrinsic subtype classified patients, 61 (41.2%), 44 (29.7%), 29 (19.5%), and 14 (9.5%) were luminal A, luminal B, human epidermal growth factor receptor 2, and triple-negative breast cancer, respectively. Luminal A subtype showed trends for superior survival compared to other subtypes. Most hormone receptor-positive patients (166 patients, 82.6%) received adjuvant endocrine treatment. Five-year completion of adjuvant endocrine treatment was associated with superior disease-free survival (DFS) in patients classified with an intrinsic subtype (hazard ratio [HR], 0.15; 95% confidence interval [CI], 0.04 to 0.49; p=0.002) and in all patients (HR, 0.16; 95% CI, 0.05 to 0.54; p=0.003). Conclusion Distribution of subtypes of MBC was similar to FBC and luminal type A was most common. Overall survival tended to be improved for luminal A subtype, although there was no statistical significance. Completion of adjuvant endocrine treatment was associated with prolonged DFS in intrinsic subtype classified patients. MBC patients tended to receive less treatment. MBC patients should receive standard treatment according to guidelines as FBC patients.

Background: Polypharmacy, the use of multiple drugs, is a growing concern in older adults. It has been reported that the prevalence of polypharmacy in elderly patients is higher in Korea than in other countries. The objective of this study was to investigate the prevalence and associated factors of polypharmacy in elderly outpatients who visited a Seoul Medical Center. Methods: We retrospectively reviewed medical records of 12,551 elderly patients aged ≥65 years who visited outpatient clinics in a public hospital in Seoul between January 1, 2018 and December 31, 2018. We defined “polypharmacy” as the use of ≥6 medications per person; “major polypharmacy,” ≥11 medications per person; and “excessive polypharmacy,” ≥21 medications per person. Multivariate logistic regression analysis was performed to estimate odds ratios (ORs) and 95% confidence intervals (CIs) to investigate the risk factors for polypharmacy. Results: Among the elderly outpatients studied, 40.7% had polypharmacy, 11.9% major polypharmacy, and 0.8% excessive polypharmacy. The lowerincome medical aid population is associated with polypharmacy (OR, 1.70; 95% CI, 1.47–1.97). Conclusion We observed a high prevalence of polypharmacy in elderly outpatients, especially the medical aid population, who visited a Korean public hospital. Nationwide vigorous efforts to assess and reduce the prevalence of polypharmacy are urgently required for the Korean older population.

Unfortunately, the authors confirmed that some of the data was missing from categories ‘Acute gastroenteritis’ and ‘Febrile seizure’ of Table 2 in the original version.

BACKGROUND: AND PURPOSE: The aim of this study was to expand the understanding of the genotype-phenotype spectrum of ATP1A3-related disorders and to evaluate the therapeutic effect of a ketogenic diet in patients with alternating hemiplegia of childhood (AHC). METHODS: The clinical information of 13 patients with ATP1A3 mutations was analyzed by performing retrospective chart reviews. Patients with the AHC phenotype who consented to ketogenic diet were included in the trial. RESULTS: Ten patients presented with the clinical phenotype of AHC, two patients presented with rapid-onset dystonia parkinsonism, and one patient presented with cerebellar ataxia, areflexia, pes cavus, optic atrophy, and sensorineural hearing loss. Two novel mutations of the AHC phenotype were identified: p.Ile363Thr and p.Asn743Ser. The clinical phenotypes of three mutations differed from those in previous reports: p.Arg597Pro, p.Thr769Pro, and p.Arg756Cys. One of the two patients who started a ketogenic diet experienced seizure provocation and so immediate stopped consuming the diet, while the other patient continued the ketogenic diet for 1 year, but this produced no clear benefit such as reduction of paroxysmal symptoms. CONCLUSIONS Our study is the first case series of ATP1A3-related disorders to be described in Korea and which further expands the understanding of its genotype-phenotype spectrum. A ketogenic diet showed no clear benefit for the patients with AHC.

Background: and Purpose: The myelin oligodendrocyte glycoprotein (MOG) antibody is detected at a high rate in childhood acquired demyelinating syndrome (ADS). This study aimed to determine the diagnostic value of the MOG antibody in ADS and the spectrum of MOGantibody-positive demyelinating diseases in children. Methods: This study included 128 patients diagnosed with ADS (n=94) or unexplained encephalitis (n=34). The MOG antibody in serum was tested using an in-house live-cell-based immunofluorescence assay. Results: The MOG antibody was detected in 48 patients (46 ADS patients and 2 encephalitis patients, comprising 23 males and 25 females). Acute disseminated encephalomyelitis (ADEM) (35.4%) was the most-common diagnosis, followed by the unclassified form (17.4%), isolated optic neuritis (ON) (15.2%), neuromyelitis optica spectrum disorder (13.0%), multiple sclerosis (MS) (10.8%), other clinically isolated syndromes [monophasic event except ADEM, isolated ON, or transverse myelitis (TM)] (8.7%), and unexplained encephalitis (4.3%). At the initial presentation, 35 out of the 46 patients with ADS had brain lesions detected in magnetic resonance imaging, and 54% of these 35 patients had encephalopathy. Nine of the 11 patients without brain lesions exhibited only ON. Thirty-nine percent of the patients experienced a multiphasic event during the mean follow-up period of 34.9 months (range 1.4–169.0 months). Encephalopathy at the initial presentation was frequently confirmed in the monophasic group (p= 0.011). Conclusions MOG antibodies were identified in all pediatric ADS phenotypes except for monophasic TM. Therefore, the MOG antibody test is recommended for all pediatric patients with ADS, especially before a diagnosis of MS and for patients without a clear diagnosis.