Two Cases of SARS-CoV-2-Positive Mothers and Their Newborns in Korea

It is unclear how severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) affects pregnant women and their fetuses or newborns. We report two infants born to mothers with coronavirus disease 2019 (COVID-19) in Korea. The first case was a healthy female baby born at 39 +3 weeks' gestation from a mother diagnosed with COVID-19. The second case was a female baby born at 38 +0 weeks' gestation. The newborn in the second case had symptoms of respiratory distress immediately after birth, and nasal continuous positive airway pressure support was applied for 8 hours. Real-time polymerase chain reaction test results for SARSCoV-2 using amniotic fluid, neonatal nasopharyngeal and oropharyngeal swabs, blood, urine, stool, and rectal swab were all negative in the 1st and 2nd days of life in both cases. Placental pathology showed acute necrotizing deciduitis and intervillous fibrin deposition with acute intervillositis. Although clinical evidence of vertical transmission was not found in our cases, with the possibility of placental inflammation, close monitoring of SARS-CoV-2 positive mothers and their newborn is required.

Epidemiology of Congenital Bleeding Disorders: a Nationwide Populationbased Korean Study

Background@#Except for data in the Korea Hemophilia Foundation Registry, little is known of the epidemiology of congenital bleeding disorders in Korea. @*Methods@#Data were obtained from the Korean Health Insurance Review and Assessment Service (HIRA) database. @*Results@#From 2010 to 2015, there were 2,029 patients with congenital bleeding disorders in the Korean HIRA database: 38% (n = 775) of these patients had hemophilia A (HA), 25% (n = 517) had von Willebrand disease (vWD), 7% (n = 132) had hemophilia B (HB), and 25% (n = 513) had less common factor deficiencies. The estimated age-standardized incidence rate (ASR) of HA and HB was 1.78–3.15/100,000 and 0.31–0.51/100,000, respectively. That of vWD was 1.38–1.95/100,000. The estimated ASR of HA showed increase over time though the number of new patients did not increase. Most patients with congenital bleeding disorders were younger than 19 years old (47.8%), and most were registered in Gyeonggi (22.1%) and Seoul (19.2%). @*Conclusion@#This is the first nationwide population-based study of congenital bleeding disorders in Korea. This study provides data that will enable more accurate estimations of patients with vWD. This information will help advance the comprehensive care of congenital bleeding disorders. We need to continue to obtain more detailed information on patients to improve the management of these diseases.

Genetic Counseling Status and Perspectives Based on a 2018 Professional Survey in Korea

BACKGROUND: Genetic counseling (GC) provides many benefits, including the identification of patients appropriate for testing, patient education, and medical management. We evaluated the current status of and challenges faced by GC practitioners in Korean hospitals.METHODS: An electronic survey was designed and conducted in 52 certified laboratory physicians belonging to the Korean Society of Laboratory Medicine, from August to September 2018. The questionnaires addressed three main categories of information: (1) current status of GC in hospitals; (2) essential qualifications of GC practitioners; and (3) challenges and perspectives for GC. Fisher's exact test was applied to analyze categorical data.RESULTS: Among a total of 52 participants who initially responded, 12 (23.1%) were performing GC either by direct or indirect care. GC clinics were opened regularly for one (33.3%) or more than three sessions (25.0%) per week; most respondents spent more time for pre-visit activities than in-person visits, both for a initial visit patient and for a follow-up visit patient. All laboratory physicians provided genetic information to their patients. Most recommended family genetic testing when indicated (91.7%), discussed disease management (75.0%), and/or ordered additional genetic testing (58.3%), and some referred patients to other specialists (8.3%).CONCLUSIONS: Both patients and laboratory physicians concede the advantage of GC performed by clinical geneticists; however, the practice of GC involves several challenges and raises some concerns. The cost and support required to implement GC need to be addressed in order to provide qualified GC in Korea.

Performance Evaluation of the ABL90 FLEX PLUS Point-of-Care Analyzer in Measuring Creatinine Levels

Background@#To diagnose acute renal failure, creatinine levels in whole blood are typically assessed using point-of-care testing (POCT) methods. The present study aimed to evaluate the performance of a newly developed POCT blood gas analyzer, the ABL90 FLEX PLUS (Radiometer, Denmark), which can measure creatinine in blood. @*Methods@#Precision and linearity of the ABL90 FLEX PLUS were evaluated and compared with those of the Beckman Coulter AU5800 (Beckman Coulter, USA), according to the CLSI guidelines for creatinine measurement performance. @*Results@#For the ABL90 FLEX PLUS, the total imprecision (%CV) levels of two control materials were measured to be 0.0% and 0.8%, while linearity was evaluated, with the R2 value measured to be 0.9993 (0.4-8.4 mg/dL). Compared to the AU5800, the ABL90 FLEX PLUS correlation coefficient (r) was found to be 0.989. The 95% limits of agreement were determined to be -0.649 and 0.643 mg/dL (-18.8% and 17.8%). @*Conclusions@#The ABL90 FLEX PLUS exhibited good performance for creatinine test. This indicates that the ABL90 FLEX PLUS can be potentially useful in clinical laboratories.

Correspondence: Response to “Eliminating or Minimizing the Effects of Cold Agglutinins on the Accuracy of Complete Blood Count Results”

No abstract available.

Diagnosis of Smith-Magenis Syndrome in a Patient with Mental Retardation and Sleep Disturbance Confirmed by Multiplex Ligation-dependent Probe Amplification

No abstract available.

Clinical Implications of Quantitative JAK2 V617F Analysis using Droplet Digital PCR in Myeloproliferative Neoplasms

BACKGROUND: JAK2 V617F is the most common mutation in myeloproliferative neoplasms (MPNs) and is a major diagnostic criterion. Mutation quantification is useful for classifying patients with MPN into subgroups and for prognostic prediction. Droplet digital PCR (ddPCR) can provide accurate and reproducible quantitative analysis of DNA. This study was designed to verify the correlation of ddPCR with pyrosequencing results in the diagnosis of MPN and to investigate clinical implications of the mutational burden. METHODS: Peripheral blood or bone marrow samples were obtained from 56 patients newly diagnosed with MPN or previously diagnosed with MPN but not yet indicated for JAK2 inhibitor treatment between 2012 and 2016. The JAK2 V617F mutation was detected by pyrosequencing as a diagnostic work-up. The same samples were used for ddPCR to determine the correlation between assays and establish a detection sensitivity cut-off. Clinical and hematologic aspects were reviewed. RESULTS: Forty-two (75%) and 46 (82.1%) patients were positive for JAK2 V617F by pyrosequencing and ddPCR, respectively. The mean mutated allele frequency at diagnosis was 37.5±30.1% and was 40.7±31.2% with ddPCR, representing a strong correlation (r=0.9712, P < 0.001). Follow-up samples were available for 12 patients, including eight that were JAK2 V617F-positive. Of these, mutational burden reduction after treatment was observed in six patients (75%), consistent with trends of hematologic improvement. CONCLUSIONS: Quantitative analysis of the JAK2 V617F mutation using ddPCR was highly correlated with pyrosequencing data and may reflect the clinical response to treatment.

Effects of Cold Agglutinin on the Accuracy of Complete Blood Count Results and Optimal Sample Pretreatment Protocols for Eliminating Such Effects

No abstract available.

A Novel 1.13 Mb Interstitial Duplication at 19q13.32 Causing Developmental Delay and Microcephaly in a Pediatric Patient: the First Asian Case Report

Only 6 patients with partial trisomy of the long arm of chromosome 19 (19q), caused by direct interstitial duplications, have been reported until today. Herein, we report a pediatric patient with a novel 1.13 Mb direct interstitial duplication within 19q13.32, which is the smallest fragment affected so far. A five-year old Korean boy of healthy parents presented with microcephaly, growth retardation, developmental delay, and craniofacial dysmorphism. Even though G-banded chromosome analysis at resolution of 550-band revealed normal karyotype, duplication of 1.13 Mb fragment within 19q13.32 was detected by array comparative genomic hybridization. Comparing with previously reported patients with pure duplication involving 19q as a sole chromosomal abnormality, our case showed the smallest duplication segment with relatively mild degree of clinical features. Our present case might serve as the landmark case among patients with 19q duplication for genotype-phenotype correlation study and further identification of critical region for 19q duplication abnormalities.

Performance Evaluation of the ichroma SMART Analyzer in Measuring C-reactive Protein and Procalcitonin Levels

BACKGROUND: For monitoring infection and inflammation episodes, biomarkers of host response, such as C-reactive protein (CRP) and procalcitonin (PCT), are now being recognized as useful tools in the diagnostic process. We aimed at evaluating the analytical performance of the recently developed semi-automated ichroma SMART system (Boditech Med Inc., Korea), which allows measurements of both CRP and PCT. METHODS: We evaluated the analytical performance of the ichroma SMART system and the agreement between its results and the laboratory standards for CRP and PCT measurements. The precision and linearity as well as the method of measurement were compared to the DxC 800 (Beckman Coulter, USA) for CRP and to the VIDAS (bioMerieux SA, France) for PCT, according to corresponding CLSI guidelines. Additionally, we evaluated the carryover rates between specimens. RESULTS: The total precision (% CV) of the ichroma SMART system in measuring low, middle, and high level controls (level 1, 2, 3) was 6.32%, 5.75%, and 3.56% for CRP, and 8.07%, 6.24%, and 6.53% for PCT. In the linearity test, R2 was 0.9997 and 0.9982 for CRP (0.1-336.8 mg/L) and PCT (0.05-60.91 ng/mL), respectively. Good correlation was observed between ichroma SMART and DxC 800 for CRP (r=0.997), and between ichroma SMART and VIDAS for PCT (r=0.992). Carry-over effect was 0.02% for CRP and 0.04% for PCT. CONCLUSIONS: The ichroma SMART system showed an adequate performance and appeared to be a suitable clinical analyzer with a simple operating procedure for the measurement of CRP and PCT.

Clinical and Molecular Delineation of a Novel De Novo 4q28.3-31.21 Interstitial Deletion in a Patient with Developmental Delay

No abstract available.

A Case of Azathioprine Induced Warfarin Resistance in Behcet's Disease

Behcet's disease is characterized by recurrent oral aphthous ulcers, genital ulcers, uveitis, and skin lesions. Thrombosis associated with vascular inflammation in patients with Behcet's disease presents various clinical symptoms. Warfarin is usually administered for treatment of thrombosis. However, warfarin can interact with many medications that cause various problems. A 43-year-old woman with Behcet's disease presented with a swollen right leg. Deep vein thrombosis (DVT) was confirmed, and treated with warfarin. Due to exacerbation of Behcet's disease, she received azathioprine along with warfarin. Subsequently, the international normalized ratio (INR) decreased and DVT was exacerbated. Despite an increase in the warfarin dose, the patient did not reach the target INR. After discontinuation of azathioprine, DVT improved and the warfarin dose was decreased. There were no specific findings associated with a hypercoagulable status. This finding suggests the interaction of azathioprine and warfarin. Therefore, clinicians should be cautious regarding the possibility of drug interactions between azathioprine and warfarin.

Cys482Trp Missense Mutation in the Coagulation Factor XI Gene (F11) in a Korean Patient with Factor XI Deficiency

No abstract available.