The Assessment and Outcomes of Crossmatching in Lung Transplantation in Korean Patients

Background@#In lung transplantation, human leukocyte antigen (HLA) compatibility is not included in the lung allocation score system or considered when placing donor allografts.However, HLA matching may affect the outcomes of lung transplantation. This study evaluated the current assessment status, prevalence, and effects of HLA crossmatching in lung transplantation in Korean patients using nationwide multicenter registry data. @*Methods@#Two hundred and twenty patients who received lung transplantation at six tertiary hospitals in South Korea between March 2015 and December 2019 were retrospectively reviewed. Clinical data, including general demographic characteristics, primary diagnosis, and pretransplant status of the recipients and donors registered by the Korean Organ Transplant Registry, were retrospectively analyzed. Survival analysis was performed using the Kaplan-Meier method with log-rank tests. @*Results@#Complement-dependent cytotoxic crossmatch (CDC-XM) was performed in 208 patients (94.5%) and flow cytometric crossmatch (flow-XM) was performed in 125 patients (56.8%). Among them, nine patients (4.1%) showed T cell- and/or B cell-positive crossmatches. The incidences of postoperative complications, including primary graft dysfunction, acute rejection, and chronic allograft dysfunction in positively crossmatched patients, were not significant compared with those in patients without mismatches.Moreover, Kaplan-Meier analyses showed poorer 1-year survival in patients with positive crossmatch according to CDC-XM (P < 0.001) and T lymphocyte XM (P = 0.002) than in patients without mismatches. @*Conclusion@#Positive CDC and T lymphocyte crossmatching results should be considered in the allocation of donor lungs. If unavailable, the result should be considered for postoperative management in lung transplantation.

Chyle Leakage after Esophageal Cancer Surgery

Surgeons recommend dissecting lymph nodes in the thorax, abdomen, and neck duringsurgery for esophageal cancer because of the possibility of metastasis to the lymph nodesin those areas through the lymphatic plexus of the esophageal submucosal layer. Extensivelymph node dissection is essential for accurate staging and is thought to improve survival.However, it can result in several complications, including chyle leakage, which refersto continuous lymphatic fluid leakage and can occur in the thorax, abdomen, and neck.Malnutrition, fluid imbalance, and immune compromise may result from chyle leakage,which can be potentially life-threatening if it persists. Therefore, various treatment methods,including conservative treatment, pharmacological treatment such as octreotide infusion,and interventions such as thoracic duct embolization and surgical thoracic duct ligation,have been applied. In this article, the risk factors, diagnosis, and treatment methodsof chyle leakage after esophagectomy are reviewed.

Factors Affecting the Number of Stapler Cartridges in Complete Video-Assisted Thoracoscopic Surgery Lobectomy for Non-small Cell Lung Cancer

Background@#Video-assisted thoracoscopic surgery (VATS) lobectomy has become the major surgical option for the treatment of non-small cell lung cancer (NSCLC). Endoscopic instruments such as stapler cartridges are essential for VATS procedures. In this study, we investigated the factors that affect the number of stapler cartridges used in VATS lobectomy. @*Methods@#A retrospective analysis was conducted of patients who underwent complete VATS lobectomy for NSCLC from January 2013 to December 2015. @*Results@#In total, 596 patients underwent complete VATS lobectomy. The average number of stapler cartridges used for VATS lobectomy was 5.3±1.9. The number of stapler cartridges used for VATS lobectomy was higher in men (5.5±1.9 vs. 5.0±18, p=0.006), those aged older than 70 years (5.5±2.1 vs. 5.1±1.7, p=0.038), those who underwent upper or middle lobectomy procedures (5.7±1.9 vs. 4.1±1.2, p<0.001), those with a higher fissure sum average (p<0.001), and those in whom surgery was performed by a surgeon with a preference for staplers (5.6±2.0 vs. 4.9±1.6, p<0.001). @*Conclusion@#The number of stapler cartridges required to perform VATS lobectomy in NSCLC patients appears to be influenced by sex, age, the location of the tumor, the degree of fissure development, and the surgeon’s preference.

Emergency Pulmonary Artery–to-Systemic Artery Shunt to Break the Positive Feedback Loop of a Pulmonary Hypertensive Crisis after Neonatal Coarctation Repair

A 2.5-kg neonate with coarctation of the aorta and a small left ventricle experienced a severe pulmonary hypertensive crisis. An emergency pulmonary artery-to-systemic artery shunt was placed to break the positive feedback loop caused by pulmonary hypertension and functional mitral stenosis. This shunt provided immediate relief of suprasystemic pulmonary hypertension and the resultant low cardiac output.

Emergency Pulmonary Artery–to-Systemic Artery Shunt to Break the Positive Feedback Loop of a Pulmonary Hypertensive Crisis after Neonatal Coarctation Repair / 대한흉부외과학회지

A 2.5-kg neonate with coarctation of the aorta and a small left ventricle experienced a severe pulmonary hypertensive crisis. An emergency pulmonary artery-to-systemic artery shunt was placed to break the positive feedback loop caused by pulmonary hypertension and functional mitral stenosis. This shunt provided immediate relief of suprasystemic pulmonary hypertension and the resultant low cardiac output.

Noninvasive prenatal test for fetal chromosomal aneuploidies by massively parallel sequencing of cell-free fetal DNA in maternal plasma: The first clinical experience in Korea

PURPOSE: Noninvasive prenatal test (NIPT) by massively parallel sequencing (MPS) of cell-free fetal DNA in maternal plasma marks a significant advancement in prenatal screening, minimizing the need for invasive testing of fetal chromosomal aneuploidies. Here, we report the initial clinical performance of NIPT in Korean pregnant women. MATERIALS AND METHODS: MPS-based NIPT was performed on 910 cases; 5 mL blood samples were collected and sequenced in the Shenzhen BGI Genomic Laboratory to identify aneuploidies. The risk of fetal aneuploidy was determined by L-score and t-score, and classified as high or low. The NIPT results were validated by karyotyping for the high-risk cases and neonatal follow-up for low-risk cases. RESULTS: NIPT was mainly requested for two clinical indications: abnormal biochemical serum-screening result (54.3%) and advanced maternal age (31.4%). Among 494 cases with abnormal biochemical serum-screening results, NIPT detected only 9 (1.8%) high-risk cases. Sixteen cases (1.8%) of 910 had a high risk for aneuploidy: 8 for trisomy 21, 2 for trisomy 18, 1 for trisomy 13, and 5 for sex chromosome abnormalities. Amniocentesis was performed for 7 of these cases (43.8%). In the karyotyping and neonatal data, no false positive or negative results were observed in our study. CONCLUSION: MPS-based NIPT detects fetal chromosomal aneuploidies with high accuracy. Introduction of NIPT as into clinical settings could prevent about 98% of unnecessary invasive diagnostic procedures.

Noninvasive fetal RHD genotyping using cell-free fetal DNA incorporating fetal RASSF1A marker in RhD-negative pregnant women in Korea

PURPOSE: Conventional methods for the prenatal detection of fetal RhD status involve invasive procedures such as fetal blood sampling and amniocentesis. The identification of cell-free fetal DNA (cffDNA) in maternal plasma creates the possibility of determining fetal RhD status by analyzing maternal plasma DNA. However, some technical problems still exist, especially the lack of a positive control marker for the presence of fetal DNA. Therefore, we assessed the feasibility and accuracy of fetal RHD genotyping incorporating the RASSF1A epigenetic fetal DNA marker from cffDNA in the maternal plasma of RhD-negative pregnant women in Korea. MATERIALS AND METHODS: We analyzed maternal plasma from 41 pregnant women identified as RhD-negative by serological testing. Multiplex real-time PCR was performed by amplifying RHD exons 5 and 7 and the SRY gene, with RASSF1A being used as a gender-independent fetal epigenetic marker. The results were compared with those obtained by postnatal serological analysis of cord blood and gender identification. RESULTS: Among the 41 fetuses, 37 were RhD-positive and 4 were RhD-negative according to the serological analysis of cord blood. There was 100% concordance between fetal RHD genotyping and serological cord blood results. Detection of the RASSF1A gene verified the presence of cffDNA, and the fetal SRY status was correctly detected in all 41 cases. CONCLUSION: Noninvasive fetal RHD genotyping with cffDNA incorporating RASSF1A is a feasible, reliable, and accurate method of determining fetal RhD status. It is an alternative to amniocentesis for the management of RhD-negative women and reduces the need for unnecessary RhIG prophylaxis.

Prenatal Population Screening for Fragile X Carrier and the Prevalence of Premutation Carriers in Korea

PURPOSE: Fragile X carrier detection before or at early pregnancy through a wide screening program may not only confer a risk of having offspring with Fragile X syndrome (FXS), but may also confer a risk for Fragile X-associated primary ovarian insufficiency and Fragile X-associated tremor/ataxia syndrome. However, prior to the implementation of such a program, the carrier prevalence in a population and the availability of effective screening test should be evaluated. The aim of our study was to determine the prevalence of premutation carriers and to evaluate the feasibility of screening test. MATERIALS AND METHODS: The blood samples were obtained from 8,641 pregnant women with no family history of mental retardation. We performed a three-primer CGG repeat primed (RP) PCR using the AmplideX(TM) FMR1 PCR kit (Asuragen, Inc. Austin, TX, USA). Samples showing full mutation alleles were reflexed to Southern blot analysis for methylation status and sizing. RESULTS: Among the 8,641 women, we found 8 premutation carriers (1:1,090, 0.09%) and 46 women with an intermediate allele (1:190, 0.53%). No woman was found to carry the fully mutated allele. All the detected alleles were within the CGG repeat range of 8-117. Among the 8,641 samples, 29 and 30 CGG repeats represent 66.6% of all cases. The CGG RP PCR method provides robust detection of expanded alleles and resolves allele zygosity, thus minimizing the number of samples that require Southern blot analysis. CONCLUSION: This is the first study that has focused on the prevalence of FXS premutation carriers and FMR1 allele distribution in normal pregnant women. These data have important implications for population-based fragile X carrier screening in Korea.

Prenatal Population Screening for Fragile X Carrier and the Prevalence of Premutation Carriers in Korea

PURPOSE: Fragile X carrier detection before or at early pregnancy through a wide screening program may not only confer a risk of having offspring with Fragile X syndrome (FXS), but may also confer a risk for Fragile X-associated primary ovarian insufficiency and Fragile X-associated tremor/ataxia syndrome. However, prior to the implementation of such a program, the carrier prevalence in a population and the availability of effective screening test should be evaluated. The aim of our study was to determine the prevalence of premutation carriers and to evaluate the feasibility of screening test. MATERIALS AND METHODS: The blood samples were obtained from 8,641 pregnant women with no family history of mental retardation. We performed a three-primer CGG repeat primed (RP) PCR using the AmplideX(TM) FMR1 PCR kit (Asuragen, Inc. Austin, TX, USA). Samples showing full mutation alleles were reflexed to Southern blot analysis for methylation status and sizing. RESULTS: Among the 8,641 women, we found 8 premutation carriers (1:1,090, 0.09%) and 46 women with an intermediate allele (1:190, 0.53%). No woman was found to carry the fully mutated allele. All the detected alleles were within the CGG repeat range of 8-117. Among the 8,641 samples, 29 and 30 CGG repeats represent 66.6% of all cases. The CGG RP PCR method provides robust detection of expanded alleles and resolves allele zygosity, thus minimizing the number of samples that require Southern blot analysis. CONCLUSION: This is the first study that has focused on the prevalence of FXS premutation carriers and FMR1 allele distribution in normal pregnant women. These data have important implications for population-based fragile X carrier screening in Korea.

Noninvasive Prenatal Diagnosis using Cell-Free Fetal DNA in Maternal Plasma: Clinical Applications

Owing to the risk of fetal loss associated with prenatal diagnostic procedures (amniocentesis, chorionic villus sampling), noninvasive prenatal diagnosis (NIPD) is ultimate goal of prenatal diagnosis. The discovery of circulating cell-free fetal DNA (cffDNA) in maternal plasma in 1997 has opened up new probabilities for NIPD by Dr. Lo et al. The last decade has seen great development in NIPD. Fetal sex and fetal RhD status determination by cffDNA analysis is already in clinical use in certain countries. For routine use, this test is limited by the amount of cell-free maternal DNA in blood sample, the lack of universal fetal markers, and appropriate reference materials. To improve the accuracy of detection of fetal specific sequences in maternal plasma, internal positive controls to confirm to presence of fetal DNA should be analyzed. We have developed strategies for noninvasive determination of fetal gender, and fetal RhD genotyping using cffDNA in maternal plasma, using real-time quantitative polymerase chain reaction (RT-PCR) including RASSF1A epigenetic fetal DNA marker (gender-independent) as internal positive controls, which is to be first successful study of this kind in Korea. In our study, accurate detection of fetal gender through gestational age, and fetal RhD genotyping in RhD-negative pregnant women was achieved. In this assay, we show that the assay is sensitive, easy, fast, and reliable. These developments improve the reliability of the applications of circulating fetal DNA when used in clinical practice to manage sex-linked disorders (e.g., hemophilia, Duchenne muscular dystrophy), congenital adrenal hyperplasia (CAH), RhD incompatibility, and the other noninvasive pregnant diagnostic tests on the coming soon. The study was the first successful case in Korea using cffDNA in maternal plasma, which has created a new avenue for clinical applications of NIPD.

Incidence and Spectrum of Chromosomal Abnormalities associated with Spontaneous Abortions in Korea: 470 Products of Conception over a Period of 6 Years (2005-2010)

PURPOSE: Cytogenetic analysis of spontaneous abortions (SABs) provides valuable information to establish the causes of fetal loss, information that is essential to provide accurate reproductive and genetic counseling couples. Such analysis also provides information on the frequencies and types of chromosomal abnormalities and associated risks of recurrence. However, there have only been a few reports of chromosomal abnormalities in small samples of SABs in the Korean population. Here, we report the incidence and spectrum of chromosomal abnormalities for cases of 470 SAB in Korea. MATERIALS AND METHODS: Between 2005 and 2010, a total of 470 products of conception (POC) resulting from SABs were submitted to our laboratory for cytogenetic analysis from various medical sites in Korea. The incidences and types of specific chromosomal abnormalities were determined. The abnormalities were distinguished by gestational age at the time of SAB and by maternal age. RESULTS: The frequency of chromosomal abnormalities in POCs was 54.3% (255/470), including 228 (89.3%) numerical and 27 (10.7%: 3 balanced and 24 unbalanced) structural abnormalities. Among the numerical abnormalities, trisomy was predominant (67.0%), followed by monosomy X (12.5%), polyploidy (8.2%), triple X (0.8%), and autosomal monosomy (0.8%). The overall sex ratio (male: female) among the 470 POCs with normal and abnormal karyotypes were 0.58 and 0.65, respectively. Trisomies were identified for each autosome, with the exceptions of 1, 3, and 19. Among the 171 autosomal trisomies, trisomy 16 was the most common (19.9%), followed by trisomy 22 (13.5%), trisomy 21 (12.3%), trisomy 15 (9.9%), and trisomies 18 and 13 (5.3%). The frequency of chromosomal abnormalities decreased with gestational age and increased with maternal age, but only because of increases in trisomies and complex abnormalities. CONCLUSIONS: We have presented a large collection of cytogenetic data for SABs collected during the past 6 years and provided a database for prenatal genetic counseling of parents who have experienced SABs in Korea.

Validation of QF-PCR for Rapid Prenatal Diagnosis of Common Chromosomal Aneuploidies in Korea

PURPOSE: Quantitative fluorescent polymerase chain reaction (QF-PCR) allows for the rapid prenatal diagnosis of common aneuploidies. The main advantages of this assay are its low cost, speed, and automation, allowing for large-scale application. However, despite these advantages, it is not a routine method for prenatal aneuploidy screening in Korea. Our objective in the present study was to validate the performance of QF-PCR using short tandem repeat (STR) markers in a Korean population as a means for rapid prenatal diagnosis. MATERIALS AND METHODS: A QF-PCR assay using an Elucigene kit (Gen-Probe, Abingdon, UK), containing 20 STR markers located on chromosomes 13, 18, 21, X and Y, was performed on 847 amniotic fluid (AF) samples for prenatal aneuploidy screening referred for prenatal aneuploidy screening from 2007 to 2009. The results were then compared to those obtained using conventional cytogenetic analysis. To evaluate the informativity of STR markers, the heterozygosity index of each marker was determined in all the samples. RESULTS: Three autosomes (13, 18, and 21) and X and Y chromosome aneuploidies were detected in 19 cases (2.2%, 19/847) after QF-PCR analysis of the 847 AF samples. Their results are identical to those of conventional cytogenetic analysis, with 100% positive predictive value. However, after cytogenetic analysis, 7 cases (0.8%, 7/847) were found to have 5 balanced and 2 unbalanced chromosomal abnormalities that were not detected by QF-PCR. The STR markers had a slightly low heterozygosity index (average: 0.76) compared to those reported in Caucasians (average: 0.80). Submicroscopic duplication of D13S634 marker, which might be a unique finding in Koreans, was detected in 1.4% (12/847) of the samples in the present study. CONCLUSION: A QF-PCR assay for prenatal aneuploidy screening was validated in our institution and proved to be efficient and reliable. However, we suggest that each laboratory must perform an independent validation test for each STR marker in order to develop interpretation guidelines of the results and must integrate QF-PCR into the routine cytogenetic laboratory workflow.

Rapid prenatal diagnosis of chromosome aneuploidies in 943 uncultured amniotic fluid samples by fluorescence in situ hybridization (FISH)

PURPOSE: Fluorescence in situ hybridization (FISH) on uncultured amniotic fluid cells offers the opportunity for rapid screening of aneuploidies and has become an integral part of the current practice in many clinical cytogenetics laboratories. Here, we retrospectively analyzed the results of interphase FISH in 943 amniotic fluid samples and assessed the efficiency of FISH for rapid detection of aneuploidies. METHODS: Interphase FISH for chromosome 13, 18, and 21 was performed in 943 consecutive amniotic fluid samples for rapid diagnosis of aneuploidies referred from 2004 to 2006. Karyotypes from standard cytogenetic analysis were compared to the FISH results. RESULTS: A total of 45 chromosomal rearrangements (4.8%) were found after conventional cytogenetic analysis of the 943 amniotic fluid. After exclusion of known familiar chromosomal rearrangements and inversions (2.1%, 20/943), 2.7% (25/943) were found to have chromosomal abnormalities. Of this group, 0.7% (6/943) were chromosomal abnormalities not detectable by FISH and 2.0% (19/943) were numerical abnormalities detectable by FISH. All 14 cases of Down syndrome (Classic type, 13 cases; Robertsonian type, 1 case) and 5 cases of trisomy 18 were diagnosed and detected by FISH and there were no false-positive or -negative results (specificity and sensitivity=100%). CONCLUSION: The present study demonstrates that FISH can provide a rapid and sensitive clinical method for prenatal identification of chromosome aneuploidies. However, careful genetic counseling is essential to explain the limitations of FISH, including the inability to detect all chromosomal abnormalities and the possibilities of uninformative or false-negative results in some cases.

Clinical and Cytogenetic Findings on 31,615 Mid-trimester Amniocenteses / 대한진단검사의학회지

BACKGROUND: Since amniocentesis made prenatal diagnosis feasible in 1967, the method has become a popular tool in obstetric practices. In Korea, the demand for genetic counseling and prenatal tests has increased markedly because the number and proportion of pregnancies in women aged 35 yr and older have increased over a 20-yr period. Here we report clinical and cytogenetic findings on 31,615 mid-trimester amniocenteses. METHODS: To investigate the changes in the annual number of amniocentesis, distribution of indications and age, and cytogenetic findings and abnormality rate according to indications, this study retrospectively analyzed 31,615 cases of mid-trimester amniocentesis performed at Seoul Clinical Laboratories, an independent medical laboratory center, during the past 13 yr (1994-2007). RESULTS: The annual number of amniocenteses has increased substantially since 1994. Among the 31,615 amniocentesis cases, the maternal age between 30 and 34 yr was the most common age group (35.4%). Among clinical indications, abnormal maternal serum screening results have been the most common indication for amniocentesis since 1994. Chromosomal abnormalities were detected in 973 cases (3.1%). Down syndrome was the most common abnormality found (36.9%, 359/973). In sex chromosomal abnormalities, 53 cases of Turner syndromes, 32 cases of Klinefelter syndromes, 20 cases of triple X syndromes, and 15 cases of 47,XYY were diagnosed. Of structural rearrangements, reciprocal translocations between two autosomes were the most common (15.5%, 151/973). Abnormal ltrasonographic findings showed the highest positive predictive value (5.9%) among the clinical indications. CONCLUSIONS: The present study could be used for the establishment of a database for genetic counseling. The discovery of an abnormality provides the option of termination or continuation in the pregnancy, a more suitable obstetric management in Korea.

Clinical and Cytogenetic study on 3,672 Genetic Amniocentesis: YUMC 20 years experience from 1985 to 2004 years / 대한산부인과학회지

OBJECTIVE: To systematic analyze the change of the annual distribution and indications, age distribution of the patients and chromosomal results according to patient's age and indications in midtrimester genetic amniocentesis METHODS: This study conducted between 1985 and 2004 collected 3,672 amniocenteses procedure which were done at College of Medicine, after prenatal genetic counceling for mothers who have high risk for carrying chromosomally abnormal babies. RESULTS: 1. The incidence of amniocentesis had been in gradual increase since the 1980''s, however, the number has increased sharply for the patiences in mid 1990's. 2. Of the 3,672 amniocentesis cases, 32.2% was maternal age 30 to 34 which was most common age group and followed by age 35 to 39 was 29.9% and age 25 to 29 was 27.8%. 3. The indications for amniocentesis were advanced maternal age (36.1%), abnormal maternal serum markers (31.7%) and abnormal ultrasonographic findings which implies chromosomal abnormality (9.6%). In the 1980's, amniocentesis had earlier been used primarily for those in advanced maternal age groups, at least 35 years older. Recently maternal serum markers and ultrasonography play an important role as an indicator for the amniocentesis. 4. From the 3,672 cases, 3,556 cases showed normal diploidy and 116 cases abnormal karyotype which consisted 3.16%. In autosomal disorders, 36 Down syndrome, 15 Edward syndrome, 2 Patau syndrome were diagnosed. In Sex chromosomal anomaly, 5 Turner syndrome, 6 47XYY, and 2 Klinefelter syndrome. Add to that 31 translocation including 21 Reciprocal translocation and 10 Robertsonian translocation, and 8 deletions and 4 mosaicisms were diagnosed. Of the 354 cases with abnormal ultrasonic findings, 19 (5.4%) resulted in chromosomal anomaly. Of the 1,164 casaes with positive maternal serum markers, 42 (3.6%) resulted in chromosomal anomaly. Those who had abnormal ultrasonographic findings implying chromosomal abnormality were found to have correlation with chromosomal abnomality than other indications. CONCLUSION: Midtrimester genetic amniocentesis is an important diagnostic tool in prenatal diagnosis, of which the annual incidence has been recently increased abruptly. Not only maternal age, but the maternal serum markers and ultrasonograms should be considered in prenatal counseling. Amniocentesis should be well informed to the general population.

Rapid Prenatal Diagnosis of Trisomy 21 by Real-time Quantitative Polymerase Chain Reaction with Amplification of Small Tandem Repeats and S100B in Chromosome 21

Trisomy 21 (Down syndrome) is the most common congenital anomaly, and it occurs in one out of 700-1000 births. Current techniques such as amniocentesis and chorionic villi sampling (CVS) require lengthy laboratory culture procedures and high costs. This study was undertaken to establish a rapid prenatal diagnosis of trisomy 21 using real-time quantitative polymerase chain reaction (PCR) of fetal DNA from amniotic fluid. Real-time quantitative PCR was performed with DNA templates obtained from 14 normal blood samples, 10 normal amniotic fluid samples, 14 Down syndrome blood samples, and 7 Down syndrome amniotic fluid samples. Primers for D21S167 and S100B of chromosome 21 were used. Primers that direct the amplification of the 165-bp fragment of the insulin-like growth factor (IGF) -1 gene on chromosome 12 using a PCR primer were included to generate an internal standard for quantitation. The relative levels of D21S167 and S100B were 2.6 and 2.4 times higher in the blood of Down syndrome patients than those in the control group. The differences between these two groups were statistically significant (p-values were 0.0012 and 0.0016, respectively). The relative levels of D21S167 and S100B were 2.1 and 2.7 times higher in the amniotic fluid of Down syndrome fetuses than those in the control group. The difference between these two groups was statistically significant (p-values were 0.0379 and 0.0379, respectively). Prenatal diagnosis of trisomy 21 by real-time quantitative PCR using STR (small tandem repeats) amplification of D21S167 and S100B is a useful, accurate and rapid diagnostic method. Furthermore, it may also be useful for prenatal diagnosis with fetal DNA from maternal blood, and for preimplantation genetic diagnosis and prenatal counseling.

Cytogenetic Study in 535 Couples with Recurrent Spontaneous Abortions in Korea / 대한불임학회지

OBJECTIVE: The purposes of this study were to investigate the types and the incidences of chromosomal abnormalities, and to provide an explanation for the genetic causations of recurrent spontaneous abortions in Korean population. METHODS: Cytogenetic studies were carried out in 535 couples with at least two spontaneous first trimester abortions from January 1981 to December 2003. For karyotype analysis, we used modified Moorhead method by Giemsa staining and Giemsa-Trypsin-Giemsa banding RESULTS: The overall incidence of chromosome abnormality was 32 out of 535 cases (5.98%). There were 25 cases (4.67%) of translocation and 7 cases (1.31%) of inversion. In translocation, 5 cases (0.93%) of Robertsonian translocation and 20 cases (3.74%) of reciprocal translocation were observed. In inversion, 6 cases (1.12%) of inversion of chromosome 9 and one case (0.19%) of inversion of chromosome 18 were found. CONCLUSION: In this study, overall chromosomal abnormality rate in couples with recurrent spontaneous abortions is much higher than that in the general population. So, chromosomal analysis should be offered for the prognostic information in genetic counseling such as prenatal diagnosis in couples with repetitive reproductive failure.

Cytogenetic study in 14,402 patients referred for suspected congenital disorders in Korea: YUMC 31 years experience from 1974 to 2004 years / 대한산부인과학회지

OBJECTIVE: To make a guideline for cytogenetic study and diagnosis through systematic analysis of types and the incidences of chromosomal abnormalities obtained from various types of congenital disorder in Korea. METHODS: The cytogenetic study was performed on 14,402 patients with suspected chromosomal abnormalities at our genetic laboratory of the medical research center between January 1, 1974 to December 31, 2004 and additionally the FISH (Fluorescence in situ hybridization) study was done on 272 patients between January 1, 1998 to December 31, 2004. RESULTS: Total number of case requiring cytogenetic study were 33 in starting year (1974) and by 1983, the number increased rapidly to 481 cases. The number of case was maximum of 894 cases in 1993 and it started to decline from 1996 to 714. Overall chromosomal aberrations were 2,100 cases (14.58%). Autosomal chromosomal abnormalities were 1,257 cases (8.73%). Among those cases, Down syndrome was 848 cases (5.89%), Edward syndrome was 38 cases (0.26%), and Patau syndrome was 6 cases (0.04%) in order of frequency. Sex chromosomal abnormalities were 843 cases (5.85%) in total. Among those cases, Turner syndrome was 527 cases (3.66%), Kleinfelter syndrome was 267 cases (1.85%). Chromosomal abnormality rate in 535 couples with recurrent spontaneous abortions was 5.98% (32 couples). And chromosomal aberration in 1068 cases with primary amenorrhea was 63.95% (683 cases). The diagnostic rate of microdeletion syndrome by FISH method was 22.71%, and marker chromosome was 20.56%. CONCLUSION: From cytogenetic analysis of 14,402 cases performed in single institute during 31 years, we performed a study on the types and the incidences of chromosomal abnormalities. We hope we could suggest a guideline for studies and treatments of congenital disorders in Korea. Along with the cytogenetic study, FISH study was also required.

Rapid prenatal diagnosis for chromosomal aneuploidy using cDNA microarray-based comparative genomic hybridization / 대한산부인과학회지

OBJECTIVE: Prenatal cytogenetic diagnosis is limited to metaphase karyotype analysis of cultured cells obtained by amniocentesis or chorionic villus sampling. Moreover, genome wide analysis cannot be performed by FISH analysis using specific probe. Array comparative genomic hybridization (CGH) offers a number of advantages over conventional cytogenetic analysis and FISH. Microarray CGH can be highly comprehensive, amenable to very high resolution, sensitive and fast. The objective of this study was to determine the clinical use of cDNA microarray CGH for detection of fetal aneuploidy. METHODS: 21 amniotic fluid samples and 6 chorionic villi samples were obtained from 27 pregnant women in 9-19 gestational weeks. Genomic DNA was extracted from each sample and amplified. For cDNA microarray CGH analysis, test DNA sample and reference DNA sample were labeled with Cy3-dUTP and Cy5-dUTP, respectively. Each sample of labeled test and reference DNA was hybridized to microarray. The result was analysed with axon scanner and compared with cytogenetic analysis and FISH. RESULTS: In 27 cases, 3 cases with trisomy 21 and 1 case with trisomy 18 had increased hybridization signals on chromosome 21 and chromosome 18. One case with 45,X had decreased signals on chromosome X. One case with 46,X,i(Xq) had decreased signal on short arm of chromosome X and increased signal on long arm. And one case with 47,XYY had two fold increased signal on Y chromosome. cDNA microarray based CGH correctly identified fetal aneuploidy in all of the 7 cases with aneuploid fetuses. CONCLUSION: Prenatal genetic diagnosis by cDNA microarray-based CGH is an useful, innovative, rapid and accurate method. It is promising technique allowing rapid screening for whole chromosomal changes including aneuploidy, and may augment standard karyotyping techniques for prenatal genetic diagnosis by providing additional molecular information. This method may aid the discovery and description of minor genetic aberration, potentially enhancing future prenatal genetic diagnostic application.

Chorionic Villus Sampling: Clinical and Cytogenetic Study of the First 1,058 Cases in YUMC from 1984 to 2004 years / 대한산부인과학회지

OBJECTIVE: This study was performed to evaluate the feasibility, accuracy and safety of Chorionic Villus Sampling (CVS). METHODS: We analyzed the outcome of 1,058 cases of CVS performed for prenatal genetic diagnosis between 7 and 12 weeks of gestation in the outpatient prenatal genetic clinic in Yonsei University Medical Center (1,030 cases by trans-cervical method and 28 cases by trans-abdominal). Fetal Karyotyping was obtained by direct or indirect culture methods using Gimsa and Gimsa-Banding. RESULTS: Advanced maternal age was the most common indication for CVS (34.7%). The overall sampling success rate was 98% (1040/ 1,058), representing 92.5% in 7 to 8 weeks, 98.0% in 9 to 10 weeks, and 98.9% in 11 to 12weeks of gestation. The majority of cases (94.6%) required one or two aspirations. Cytogenetic analysis routinely included direct overnight and long-term culture methods, which revealed 27 chromosomal abnormalities (2.6%). Of 1,040 cases in which CVS were successful, 989 delivered normal baby, 23 resulted in fetal loss, 25 had therapeutic termination (24 with chromosome abnormalities and 1 with normal chromosome with huge myoma), and 3 with chromosome abnormalities were loss to follow up. The overall fetal loss rate was 2.2% (23/1,058). No congenital anomalies were found to be related to CVS in these series. CONCLUSION: When performed by experienced operators and cytogeneticists beyond 9 weeks of gestation, CVS is a feasible, accurate and safe method for prenatal genetic diagnosis capable of replacing genetic amniocentesis.