Transition from Secondary Blood Test to Nucleic Acid Amplification for Safe Allograft Transplantation

Background@#Given the incubation period of viral diseases, a secondary blood test should be performed at least 3–6 months after the first test to ensure the safety of allogenic bone grafts obtained from living donors in some tissue banks. The allograft is discarded if a secondary blood test was unavailable. The secondary blood test can be replaced with a nucleic acid amplification test (NAT) to reduce the discarded allograft. The purpose of this study was to analyze the comparative efficiency of secondary blood test and NAT to determine the donor suitability of allogenic bone grafts. @*Methods@#Allogenic bones were retrieved from 452 living donors between January 2013 and December 2019. A secondary blood test was conducted in 182 patients and NAT was performed in 270 patients. The average age of donors was 69 years (range, 33– 87 years). They included 86 men and 366 women. The initial blood tests including hepatitis B, hepatitis C, AIDS, and syphilis were conducted before retrieving grafts. The results were analyzed after the secondary blood test was performed at least 3 to 6 months after the first test because of the incubation period of the viral diseases. NAT was performed within 2 months after the first blood test. @*Results@#Sixty-seven of the 452 cases (14.8%) were discarded. In the secondary blood test group, 50 out of 182 cases (27.4%), and in the NAT group, 17 out of 270 cases (6.3%) were discarded. None of the 132 donors tested positive in the secondary blood test after testing negative in the first test. @*Conclusions@#It is extremely rare that the secondary blood test yields positive results in donors who tested negative in the initial test. However, quite a few grafts are discarded only because the secondary blood test is not available. In terms of economics and ethics, the secondary blood test may not be necessary or if required, a single test such as NAT for infectious diseases may be performed to determine donor suitability of allogenic bone.

Clinical characteristics of obese boys and girls in a high school: focused on abdominal fat indices, fatty liver and carotid intima-media thickness / 소아과

PURPOSE: Our study aimed to evaluated sex differences in clinical features of obese high school students. METHODS: One hundred three obese high school students (body mass index [BMI]> or =85th percentile) and 51 control students (BMI<85th percentile) were enrolled in this study. Anthropometric measurements were performed. Fasting serum glucose, insulin, aspartate aminotransferase, alanine aminotransferase, total cholesterol, triglyceride, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and high-sensitive C-reactive protein were measured. Abdominal fat thickness, degree of fatty liver, and carotid intima-media thickness were measured by ultrasound. RESULTS: In control and obese groups, waist circumference was significantly longer in boys but body fat mass was significantly higher in girls. In the control group, total cholesterol and LDL-C were higher in girls. In the obese group, however, aspartate aminotransferase, alanine aminotransferase and triglyceride were higher and HDL-C was lower in boys. Preperitoneal fat thickness was significantly higher in obese girls. In obese group, the degree of fatty liver was significantly higher in boys. Carotid intima-media thickness was not significantly different between boys and girls. CONCLUSION: Obese adolescents had distinguishable sex differences in body measurements, metabolic abnormalities, abdominal fat thickness and fatty liver. We can infer that these characteristics may extend into adult obesity.

Body composition by bioelectrical impedance analysis in children below 7 years old / 소아과

PURPOSE: Body composition is important to define and manage obesity and undernutrition. Obesity is a significant health problem with medical and psychological consequences for children and adolescents. Body composition analysis (BIA) is a simple, rapid, noninvasive, and reproducible technique. However, comparative analysis of body composition has not been done in young children below 7 years old. The aim of this study is to estimate antropometric data and body composition by BIA, and to investigate the correlation between anthropometric data and fat mass or fat percent in young children. METHODS: We measured height, weight, body mass index (BMI), fat mass, and fat percent by BIA in 1,376 children aged 3-6 years of whom 688 were males and 688 were females. RESULTS: Fat mass, fat percent, intracellular fluid, extracellular fluid, protein, and minerals were significantly higher in the obese group. A significant positive correlation exists between fat mass and BMI or weight. A significant positive linear correlation was also noted between fat percent and BMI. Protein, weight, fat mass, and fat percent were significantly different among groups. CONCLUSION: BIA is an objective, accurate method to estimate body fat in childhood obesity cases. Fat mass and fat percent data acquired by using BIA highly correlated with BMI. However, a large-scale study is needed to diagnose obesity in young children.

The first Korean case of poland-Mobius syndrome associated with dextrocardia / 소아과

Poland syndrome is characterized by unilateral absence or hypoplasia of the pectoralis muscle and variable degree of ipsilateral hand anomalies. Mobius syndrome is a congenital neurological disorder characterized by complete or partial facial paralysis. Although the pathogeneses of these diseases are not well-characterized, diminished blood flow to the affected side is thought to play a role. A male infant weighing 2.670 g was born at 38+3 weeks of gestation with left facial paralysis, left chest wall defect with dextrocardia, and symbrachydactyly between the second and third fingers. The combination of Poland-Mobius syndrome is rare, and only 2 cases associated with dextrocardia have been reported worldwide. Here, we report the first case of Poland-Mobius syndrome associated with dextrocardia in Korea.

Imaging Characteristics of Computed Radiography Systems / 의학물리

With recent advancement of the medical imaging systems and picture archiving and communication system (PACS), installation of digital radiography has been accelerated over past few years. Moreover, Computed Radiography (CR) which was well established for the foundation of digital x-ray imaging systems at low cost was widely used for clinical applications. This study analyzes imaging characteristics for two systems with different pixel sizes through the Modulation Transfer Function (MTF), Noise Power Spectrum (NPS) and Detective Quantum Efficiency (DQE). In addition, influence of radiation dose to the imaging characteristics was also measured by quantitative assessment. A standard beam quality RQA5 based on an international electro-technical commission (IEC) standard was used to perform the x-ray imaging studies. For the results, the spatial resolution based on MTF at 10% for Agfa CR system with I.P size of 8x10 inches and 14x17 inches was measured as 3.9 cycles/mm and 2.8 cycles/mm, respectively. The spatial resolution based on MTF at 10% for Fuji CR system with I.P size of 8X10 inches and 14x17 inches was measured as 3.4 cycles/mm and 3.2 cycles/mm, respectively. There was difference in the spatial resolution for 14x17 inches, although radiation dose does not effect to the MTF. The NPS of the Agfa CR system shows similar results for different pixel size between 100 micrometer for 8x10 inch I.P and 150 micrometer for 14x17 inch I.P. For both systems, the results show better NPS for increased radiation dose due to increasing number of photons. DQE of the Agfa CR system for 8X10 inch I.P and 14x17 inch I.P resulted in 11% and 8.8% at 1.5 cycles/mm, respectively. Both systems show that the higher level of radiation dose would lead to the worse DQE efficiency. Measuring DQE for multiple factors of imaging characteristics plays very important role in determining efficiency of equipment and reducing radiation dose for the patients. In conclusion, the results of this study could be used as a baseline to optimize imaging systems and their imaging characteristics by measuring MTF, NPS, and DQE for different level of radiation dose.