Dynamics of Gut Microbiota According to the Delivery Mode in Healthy Korean Infants

Microbial colonization of the infant gut is unstable and shows a wide range of diversity between individuals. Gut microbiota play an important role in the development of the immune system, and an imbalance in these organisms can affect health, including an increased risk of allergic diseases. Microbial colonization of young infants is affected by the delivery mode at birth and the consequent alterations of gut microbiota in early life affect the development of allergic diseases. We investigated the effects of the delivery mode on the temporal dynamics of gut microbiota in healthy Korean infants. Fecal samples were collected at 1-3 days, 1 month, and 6 months after birth in six healthy infants. Microbiota were characterized by 16S rRNA shotgun sequencing. At the first and third days of life, infants born by vaginal delivery showed a higher richness and diversity of gut microbiota compared with those born by cesarean section. However, these differences disappeared with age. The Bacteroides genus and Bacteroidetes phylum were abundant in infants born by vaginal delivery, whereas Bacilli and Clostridium g4 were increased in infants born by cesarean section. The Firmicutes phylum and Bacteroides genus showed convergent dynamics with age. This study demonstrated the effect of delivery mode on the dynamics of gut microbiota profiles in healthy Korean infants.

Pediatric adverse drug reactions collected by an electronic reporting system in a single tertiary university hospital

PURPOSE: The incidence of adverse drug reactions (ADRs) is increasing. However, studies on the prevalence of ADRs in children are rare. The aim of this study was to investigate the causative drugs and clinical features of ADRs for children in a tertiary university hospital of Korea. METHODS: We retrospectively collected ADRs by a computerized self-reporting system in Asan Medical Center. ADRs of children under the age 18 were collected from January 2005 to August 2015, and we analyzed only ADRs containing current symptoms among total ADR data. RESULTS: A total of 1,408 ADR cases were reported, There were 764 male (54.3%) and 644 female patients (45.7%), and the mean age was 11.5±5.8 years (range, 0–18 years). Antibiotics (n=479, 34.0%) were the most common causative drugs, followed by tramadol (n=173, 12.3%), nonsteroidal anti-inflammatory agents (NSAIDs) and acetylsalicylic acid (n=103, 7.3%), narcotics (n=91, 6.5%), antineoplastics (n=87, 6.2%), and sedatives (n=82, 5.8%). The most common clinical features were skin manifestations (n=500, 34.4%). Gastrointestinal symptoms (n=435, 29.9%) were the second most common clinical features, followed by neuropsychiatric symptoms (n=155, 10.7%) and respiratory symptoms (n=123, 8.5%). Among antibiotics, glycopeptides (n=110, 23.0%), third-generation cephalosporins (n=83, 17.3%), and penicillin/β-lactamase inhibitors (n=60, 12.7%) were the most frequently reported causative drugs. CONCLUSION: Antibiotics were the most reported common causative drugs of ADRs in children, followed by tramadol, NSAID, and narcortics. Compared with adults, the prevalence of contrast medium-induced ADR was lower in children with a higher prevalence of sedative-associated ADR. Greater attention to possible ADRs in children is needed among medical personnel.

The prevalence and risk factors of allergic rhinitis from a nationwide study of Korean elementary, middle, and high school students

PURPOSE: We investigated the prevalence and risk factors of allergic rhinitis (AR), nationwide in random children and adolescents of Korea. METHODS: A modified International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire survey was done in 1,820 children from elementary, middle, and high school nationwide in Korea. The subjects were selected by the stratifying sampling method by school grade and five regions. Current AR was defined as having AR symptoms during the last 12 months with a history of physician-diagnosed AR. Skin prick tests for 18 common allergens were performed. RESULTS: The number of males was 945, and that of females was 875. The mean age of the patients was 12.61+/-3.40 years. The prevalence of current AR and atopic current AR were 29.0% and 18.7%, respectively. Risk factors for current AR were male (adjusted odds ratio [aOR], 1.486; 95% confidence interval [CI], 1.189-1.856), family history of paternal AR (aOR, 3.208; 95% CI, 2.460-4.182), family history of maternal AR (aOR, 3.138; 95% CI, 2.446-4.025), antibiotic use in infancy (aOR, 1.547; 95% CI, 1.228-1.949), mold exposure during infancy (aOR, 1.416; 95% CI, 1.103-1.819), mold exposure during the last 12 months (aOR, 1.285; 95% CI, 1.012-1.630), and sensitization on skin prick tests (aOR, 2.596; 95% CI, 2.055-3.279). Risk factors for atopic current AR were the same as those of current AR, whereas breast-milk feeding (aOR, 0.720; 95% CI, 0.530-0.976) was a protective factor. Sensitized allergens as risk factors for current AR were Dermatophagoides pteronyssinus, Dermatophagoides farina, ragweed, mugwort, oak, alder, birch, Japanese hop, cat, and dog. CONCLUSION: The prevalences of current AR and atopic current AR were 29.0% and 18.7%, respectively. Male, sex parental AR, antibiotic use in infancy, mold exposure during the last 12 months, mold exposure during infancy, and atopic sensitization were risk factors for current AR. Breast-milk feeding was a protective factor for atopic current AR. Aeroallergen sensitization was an important risk factor for AR.

Computer-assisted Evaluation of Pedicle Screw Position on CT Images / 대한정형외과학회잡지

PURPOSE: The purpose of this study was to develop a personal computer-based method to facilitate the evaluation of pedicle screw position on computed tomography (CT) scan images and to assess its diagnostic value. MATERIAL AND METHOD: A personal computer-based method was developed using the CT images of 17 patients having a total of 84 pedicle screws. Images with a window range of -2, 000 to +3, 000 were inverted; a multiplanar reconstruction viewer was then produced to create these images in the sagittal and coronal planes. Finally, lines circumscribing the threaded portion of screws were drawn on the images. For CT images of thirty-two pedicle screws placed in the lumbar vertebrae of four pigs, screw locations were evaluated by 6 orthopaedic surgeons by our method and by conventional bone window setting. The diagnostic values of the two methods were calculated and compared. RESULT: Our method significantly improved the specificity (from 82% to 94%, p=0.007), the positive predictive value (from 79% to 92%, p=0.015), and inter-observer agreement (from 0.61 to 0.78, p<0.001) in terms of identifying misplaced screws. CONCLUSION: The described method improves the diagnostic accuracy and inter-observer reliability for the identification of misplaced pedicle screws on CT scan images.

Surgical Simulation for Placement of Isometric Point of Anterior Cruciate Ligament: A System using Three-dimensional Computer Models and Rapid Prototyping Models / 대한정형외과학회잡지

PURPOSE: This research aims at developing a simulation system for training of the correct placement of isometric points in arthroscopic reconstruction of anterior cruciate ligaments, using personal computer-based software and rapid prototyping knee models. MATERIALS AND METHODS: CT scan images of the knee joints of thirteen patients were used. Simulation software was developed on V-works(Clinic3D Inc.), a three-dimensional medical imaging system. Rapid prototyping models were made of hardened starch with a 0.178 mm slice thickness. RESULTS: In the first phase, trainee surgeons can study the positions of the bony attachments of healthy anterior cruciate ligaments, and compare their multiplanar reformatting images and a three-dimensional computer model of the bones. In the second phase, trainee sur-geons can place isometric points on the three-dimensional computer models and compare the results with the points set by a supervis-ing surgeon. Finally, rapid prototyping models, which are almost identical to the actual bones, are produced to allow the trainees to observe the isometric points marked on the models. CONCLUSION: Our system can provide a patient-specific simulation environment for beginners at arthroscopic anterior cruciate ligament reconstruction. It can be used as an educational and training tool for locating the isometric point of the anterior cruciate ligament during an operation.

A Patient-Specific Surgical Simulation System for Spinal Screw Insertion Composed of Virtual Roentgenogram, Virtual C-Arm, and Rapid Prototyping / 대한정형외과학회잡지

PURPOSE: This research aims at developing a PC-based spinal screw insertion simulation program and rapid prototyping spine models for correct placement of spinal screws. MATERIALS AND METHODS: We developed a surgical simulator on top of a 3-D medical imaging system V-worksTM (Cybermed, Inc.) and used Z-402 (Z Corporation) models made of hardened starch. RESULTS: The first phase is training surgeons using the simulation software. The trainees could simulate the insertion of spinal screws using the PC-based software. The second phase is a planning software to determine the ideal entry point and insertion angle using the multiplanar reconstruction images of spine CT. Finally, a rapid prototyping model of which the size is identical to the actual bone is produced for simulation surgery prior to the actual one. CONCLUSION: The system provides a tool for educating and training the beginners of spinal screw insertion, and also a pre-surgical simulation environment for planning the actual insertion surgery.