Familial male-limited precocious puberty (FMPP) is a rare form of gonadotropin-independent precocious puberty that is caused by an activating mutation of the LHCGR gene. Herein, we report a case of FMPP with a mutation of the LHCGR gene in a Korean boy with familial history of precocious puberty through 3 generations. A 16-month-old boy presented with signs of precocious puberty, including pubic hair, acne, and increased growth velocity. The patient's grandfather and father had a history of precocious puberty and profound short stature. On physical examination, the patient had prepubertal testes with pubic hair development appropriate for Tanner stage II. The stretched penile length was 7 cm (>2 standard deviation score), and observed bone age was that of a 4-year-old boy. Laboratory findings showed high serum testosterone (5.74 ng/mL [appropriate for Tanner IV–V]; normal range, <0.05 ng/mL) with suppressed luteinizing hormone (<0.07 mIU/mL) and normal serum level of follicular stimulating hormone (0.56 mIU/mL; normal range, 0.38–1.11 mIU/mL). Genetic testing revealed a pathogenic variant of LHCGR (c.1730 C>T (p.Thr577Ileu)), confirming FMPP. Bicalutamide and anastrozole were administered, and pubertal progression was sufficiently suppressed without any specific side effects. To our knowledge, this is the first case of genetically confirmed FMPP in Korea.

Background/aims: Opinions differ regarding vibration-controlled transient elastography and magnetic resonance elastography (VCTE/MRE) cut-offs for diagnosing advanced fibrosis (AF) in patients with non-alcoholic fatty liver disease (NAFLD). We investigated the diagnostic performance and optimal cut-off values of VCTE and MRE for diagnosing AF. Methods: Literature databases, including Medline, EMBASE, Cochrane Library, and KoreaMed, were used to identify relevant studies published up to June 13, 2023. We selected studies evaluating VCTE and MRE regarding the degree of liver fibrosis using liver biopsy as the reference. The sensitivity, specificity, and area under receiver operating characteristics curves (AUCs) of the pooled data for VCTE and MRE for each fibrosis stage and optimal cut-offs for AF were investigated. Results: A total of 19,199 patients from 63 studies using VCTE showed diagnostic AUC of 0.83 (95% confidence interval: 0.80–0.86), 0.83 (0.80–0.86), 0.87 (0.84–0.90), and 0.94 (0.91–0.96) for ≥F1, ≥F2, ≥F3, and F4 stages, respectively. Similarly, 1,484 patients from 14 studies using MRE showed diagnostic AUC of 0.89 (0.86–0.92), 0.92 (0.89–0.94), 0.89 (0.86–0.92), and 0.94 (0.91–0.96) for ≥F1, ≥F2, ≥F3, and F4 stages, respectively. The diagnostic AUC for AF using VCTE was highest at 0.90 with a cut-off of 7.1–7.9 kPa, and that of MRE was highest at 0.94 with a cut-off of 3.62–3.8 kPa. Conclusions VCTE (7.1–7.9 kPa) and MRE (3.62–3.8 kPa) with the suggested cut-offs showed favorable accuracy for diagnosing AF in patients with NAFLD. This result will serve as a basis for clinical guidelines for non-invasive tests and differential diagnosis of AF.

Pure-tone audiometry, using an audiometer, is the fundamental hearing test for diagnosing hearing loss. The requirements of the devices and the detailed process for calibrating the related equipment are described in international standards. However, traceable calibration and uncertainty evaluation processes are not widely accepted or applied to the qualification and maintenance of audiometric equipment. Here, we briefly review standard measurement systems for audiometric devices and introduce their calibration procedures. The uncertainty of each calibration process was investigated, and its impact on hearing test results was considered. Our findings show that the traceability of each procedure can be secured, satisfying the uncertainty requirement and being sufficiently smaller than the permissible deviation from the audiometer requirement. To guarantee the objectivity and reliability of hearing tests and maintain low uncertainty, close cooperation and mutual understanding between the metrology field and the medical community are necessary.

Objective: Research on neural correlates in the prefrontal cortex (PFC) associated with self-injurious behavior has mainly been performed in adults. However, studies on adolescents are scarce. We aimed to investigate the activation and connectivity of the PFC between adolescents with self-injurious behavior (ASI) and psychiatric controls (PC) using functional near-infrared spectroscopy (fNIRS). Methods: We used an emotion recognition task during fNIRS to assess 37 adolescents (23 with self-injurious behavior and 14 PC) between June 2020 and October 2021 and compared connectivity and activation between the two groups. We also measured adverse childhood events (ACE, Adverse Childhood Experiences) and performed a correlation analysis of channel activation according to ACE total scores. Results: The difference in activation between the groups was not statistically significant. The connectivity of channel 6 was statistically significant. The interaction between channel 6 and the ACE total score showed statistical significance between the two groups(t[33] -2.61; p=0.014). The ASI group showed a negative correlation with the total ACE score. Conclusion This is the first study to investigate PFC connectivity using fNIRS in ASI. It has the implication of a novel attempt with a practically useful tool to uncover neurobiological differences among Korean adolescents.

This study explores the internal standards for hearing tests and benefits of implementing international standard protocols, including the International Organization for Standardization (ISO) and International Electrotechnical Commission (IEC), and discusses how ISO and IEC standards provide a framework for designing, calibrating, assessing hearing test instruments and methods, and exchanging and comparing data globally. ISO and IEC standards for hearing tests improve accuracy, reliability, and consistency of test results by applying standardized methods and environments. Moreover, they promote international harmonization and data interoperability, enabling information exchange and research collaboration. Those standards for hearing tests are beneficial but have challenges and limitations, such as variation in equipment and calibration, lag in updating standards, variation in implementation and compliance, and lack of coverage of clinical aspects, cultural diversity, and linguistic diversity. These affect the quality and interpretation of test results. Adapting ISO or IEC standards locally would improve their applicability and acceptability, while balancing customization and compatibility with global standards.

Most eukaryotic cells have mitochondrial networks that can change in shape, distribution, and size depending on cellular metabolic demands and environments. Mitochondrial quality control is critical for various mitochondrial functions including energy production, redox homeostasis, intracellular calcium handling, cell differentiation, proliferation, and cell death. Quality control mechanisms within mitochondria consist of antioxidant defenses, protein quality control, DNA damage repair systems, mitochondrial fusion and fission, mitophagy, and mitochondrial biogenesis. Defects in mitochondrial quality control and disruption of mitochondrial homeostasis are common characteristics of various kidney cell types under hyperglycemic conditions. Such defects contribute to diabetes-induced pathologies in renal tubular cells, podocytes, endothelial cells, and immune cells. In this review, we focus on the roles of mitochondrial quality control in diabetic kidney disease pathogenesis and discuss current research evidence and future directions.

Rhabdomyolysis associated with psychogenic polydipsia and hyponatremia is a rare condition that can cause substantial morbidity and mortality. We report a 14-year-old boy with psychogenic polydipsia who experienced recurrent hyponatremia and subsequent rhabdomyolysis. Treatment involved intravenous fluids and restriction of oral water intake. This case emphasizes the importance of early recognition and management of this condition. The possibility of rhabdomyolysis should be considered in patients with hyponatremia who have myalgia.

Background/Aims: Chronic hepatitis C is a major risk factor for liver cirrhosis, hepatocellular carcinoma, and hepatic failure. Although traditional practices, including acupuncture, tend to increase the risk of HCV infection, the association remains controversial. Therefore, the current meta-analytical study was undertaken to evaluate the risks of acupuncture and hepatitis C transmission. Methods: Two researchers independently screened studies from the databases encompassing the period from inception to May 12, 2022. Baseline demographics, HCV transmission OR, and 95% CIs were extracted, pooled, and analyzed using random-effect models.Subgroup analyses utilizing study design and ethnicity were performed. Heterogeneity and publication bias were analyzed using the Higgins I2 test and funnel plots, respectively. Results: In all, 28 studies with 194,826 participants (178,583 controls [91.7%] vs. 16,243 acupuncture users [8.3%]) were included in the final analysis. The pooled analysis showed that acupuncture users had a significantly higher HCV transmission rate than controls with heterogeneity (OR, 1.84 [1.46–2.32]; p<0.001; I2 =80%). In the subgroup analysis, both cross-sectional case-control (n=14; OR, 1.96 [1.47–2.61]; p<0.001; I2 =88%) and cross-sectional studies (n=12; OR, 1.85 [1.32–2.61]; p<0.001; I2 =0%) showed significantly higher HCV infection rates in the acupuncture group than in the control group. Both Asian and non-Asian acupuncture users showed a higher HCV transmission risk than the controls (all Ps <0.001). No significant publication bias was observed. Conclusions Our findings indicate that acupuncture increases the risk of HCV transmission. Due to HCV's contagiousness, unsafe medical and social practices (including acupuncture) should be performed with caution.

Fetomaternal hemorrhage (FMH) is due to the entry of fetal blood into the maternal circulation. Although very rare, FMH complicates pregnancies, presents with severe symptoms, and leads to fetal death. Majority of FMH cases are idiopathic and difficult to diagnose. The known used diagnostic tests are Kleihauer-Betke Test (KBT) and flow cytometry, which can detect fetal hemoglobin in the maternal blood. However, such methods have limited use because of low sensitivity, labor-intensive and error-susceptible procedures, poor reproducibility, and tendency to overestimate the FMH volume. Other tests include high performance liquid chromatography (HPLC) and alpha-fetoprotein (AFP) tests, which can be as favorable to confirm FMH as KBT. However, in case of acute FMH, the diagnostic results of KBT, flow cytometry, and HPLC may be false negative. AFP test is a noninvasive, fast, easily assessable, adjuvant, and confirmatory diagnostic test. Published Korean articles show confirmed FMH by KBT or HPLC in singleton late-preterm and term neonates. Herein, we report a case of monochorionic diamniotic twin neonates (birth weight <1,500 g) who presented borderline fetal hemoglobin level because of acute FMH and were diagnosed with FMH by maternal AFP. Our experience of diagnosing FMH rapidly by AFP test will be very helpful to clinicians for the prevention and treatment of FMH during pregnancy.