جستجوی مقالات مرتبط با کلیدواژه « تشخیص قبل از تولد » در نشریات گروه « پزشکی »

Sacrococcygeal Teratoma (SCT) is one of the most frequently prenatally diagnosed neoplasias. SCT is classified into four types regarding its location. Type 4 tumors are usually diagnosed in the postnatal period and have higher potential for malignancy. we report a case of type 4 SCT that detected by ultrasonography at a gestational of 21.6 weeks. Ultrasound scan in our hospital showed a cystic lesion with septation (39.5 × 14.3 × 8.62 mm) in the fetal sacrococcygeal region. Tumor growth and heart failure monitored with serial scans. At 39 weeks of gestation cesarean section was performed due to previous cesarean. Afterward surgery was performed successfully at 72 hours of life. The pathologic diagnosis was Mature cystic teratoma. Follow up controls revealed normal and healthy child growth.

Beta thalassemia is one of the most common hereditary diseases in Iran. The birth of a child with thalassemia causes many social and economic problems for parents and the health care system. Nowadays, prenatal screening programs to detect beta thalassemia have received much attention in the country. The aim of the present study was the determination and sampling of chorionic villi for the diagnosis of beta-thalassemia major in the first trimester of pregnancy in south-western Iran.

The present descriptive-prospective and practical study was conducted in 2021 on couples suffering from thalassemia minor and referred to the Narges Genetics Laboratory in Ahwaz, Iran. For preventive measures, blood samples were taken from volunteers. At that point, the couples who had HbA2 above 3.5 and were in the 10th to 13th week of pregnancy continued the treatment by performing chorionic villus sampling in order to evaluate the health of the fetus. Chorionic villus sampling was performed under local anesthesia with a needle from the abdominal area of pregnant women, and about 5-10 cc of placental trophoblast villi were collected. The collected data were analyzed using t-test and chi-square statistical tests.

A total of 91 pregnant women underwent chorionic villus sampling. Thirty-eight individuals (41.8%) had thalassemia minor, 25 individuals (27.5%) had thalassemia major, the familial relationship between couples was also examined, and there was no significant association between the familial relationship and occurrence of thalassemia major. 20 people (30%) had a child with thalassemia major and 60 people (66%) had a child with thalassemia minor. Fetuses with thalassemia major in mothers with blood type A+, 38 subjects (42%) and O+ 35 subjects (38.4%), the prevalence of thalassemia major was higher in the Fars subjects, the highest in 39 subjects (42.8%), and the lowest was the Kurdish people with one person (1 percent).

The technique of chorionic villus sampling is an accurate method with no significant risk to both mother and fetus. This method can be used to diagnose beta thalassemia before birth.

Thalassemia is a genetic disease with an autosomal recessive pattern. Prenatal diagnosis (PND) and termination of pregnancy in the case of fetus infection is the best way to prevent this disease. This study was performed with aim to evaluate the incidence rate and causes of new cases of major β-thalassemia (MBT) after implementing the national prevention program in Kerman University of Medical Sciences.

This was descriptive and analytical study on health system research. Information of patients (Date of birth, status of other siblings) and carrier couples (year of marriage, kinship relationship, performing screening at the time of marriage, history of surveillance, and causes of the birth of beta-thalassemia patient) was obtained from the data available in the Health Department of Kerman Universities of Medical Sciences from 2011 to 2019. Data were analyzed by SPSS (Version 24) using Fisher's exact test. 

The 9-year incidence rate in the whole region was 0.55 per 10,000 live births. The success rate of the program in the whole region was 84.37%. Fifteen patients were born between 2011 and 2019. The most important cause of MBT incidence was the lack of identification of thalassemia couples and their lack of awareness about their condition (46.6%). Nine (60%) of the patients' parents had consanguineous marriages. There was no statistically significant relationship between causes of new cases of MBT and the level of education and occupation of the patients' parents (P>0.05).

Although the implementation of the prevention program has significantly reduced the number of new cases of MBT, appropriate planning to improve the quality of counseling services and carrier couples care and increase the level of awareness and change the attitude of target groups to eliminate the incidence of the disease is necessary.

 Congenital heart defects (CHDs) are the most costly congenital disorders and despite significant advances in the diagnostic modalities, still its perinatal and neonatal consequences require extensive studies. In the current study, we investigated diagnostic value of fetal heart echocardiography for CHDs diagnosis while postnatal echocardiography was considered as Gold standard. Additionally, maternal and perinatal outcomes were evaluated.

 In this prospective Cohort study, 400 high risk pregnant women with regards to carrying a fetus with CHDs underwent fetal echocardiography during pre and postnatal period and maternal, fetal and neonatal outcomes were followed. Moreover, diagnostic value of fetal echocardiography for predicting CHDs was calculated.

 Among 400 fetal echocardiographies done, CHDs was found in
63 fetuses and consequently postnatal echocardiography confirmed the diagnosis in 52 (82.53%) of them. The most common CHDs were atrial and ventricular septal defects (ASD and/or VSD). Although there were no association between presence of CHDs with consanguineous marriage, maternal age, maternal body mass index, smoking, pregnancy complications, fetal weight, gestational age, neonatal gender, and associated anomalies, the first and fifth Apgar Scores were significantly lower in neonates with CHDs on postnatal echocardiography.

 Second trimester fetal echocardiography, especially among high risk mothers has high diagnostic value for fetal CHDs diagnosis. This Imaging technique can lessen postnatal complications by facilitating early diagnosis and subsequent planned delivery in a proper well-equipped center.

Aneuploidies are of the most important fetal abnormalities. Diagnostic value and efficacy of NIPT assay in the groups with abnormal results for first trimester combined screening test is not well defined. Therefore, this study was performed aimed to survey the sensitivity and specificity of NIPT for aneuploidies diagnosis in women with moderate risk for trisomy at first trimester combined screening test.

This prospective cohort study was performed in 2017-2018 on 447 women with singleton pregnancy and gestational age of 11 to 13 weeks and 6 days who had moderate risk for trisomy. NIPT analysis was done in all women with moderate risk (1/250 to 1/1500) and was compared with the results from karyotype and phenotype analysis in neonates. NIPT diagnostic accuracy for chromosomal abnormalities was calculated. Data were analyzed using SPSS statistical software (version 22).

Two cases with trisomy 21 (0.06%) and one case with trisomy 18 (0.03%) were diagnosed. These three cases were confirmed with amniocentesis and the pregnancy was ended. The neonates' analysis showed normal phenotype results in all of them and NIPT diagnostic accuracy for trisomy 21 and 18 was calculated 100%.

In addition to maintain combined screening test benefits, using NIPT is accompanied by high diagnostic accuracy for fetal chromosomal abnormalities assessment.

Phenylketonuria (PKU) is the most common inherited metabolic disease in Iran that can be prevented by prenatal diagnostic tests (PND). This study was performed aimed to determine the incidence of PKU and the effect of implementing a prevention program on reducing its incidence in the population covered by Kerman University of Medical Sciences.

This was a descriptive study on health system research. All PKU carrier couples and patients covered by Kerman University of Medical Sciences in 2019 were studied. Data were obtained from the national form of epidemiological study of genetic diseases and genetic surveillance form from the Deputy Minister of Health. Frequency tables and graphs were used to describe the information.

In this study, 68 patients and 63 carrier couples were covered and 37 (60.6%) carrier couples were at risk of having a sick child and all of them were under the care of health care centers. For 91.9% of them and 61.9% high-risk relatives, the type of gene mutation was determined. PND tests were performed on 28 (87.5%) pregnant women. Seven affected fetuses were diagnosed, all of which were aborted with parental consent. 32 high-risk couples (86.5%) used safe method of contraception. The 13-year incidence of PKU in the whole region was 1.13 and the expected incidence was 1.36 per 10,000 live births.

Implementation of prevention program had an effect on reducing the incidence of PKU. The high frequency of consanguineous marriages can affect the high incidence of PKU. It is necessary to identify the patient's relatives who are at risk of having a sick child (consanguineous marriage), refer them to a genetic counseling center and determining their status can be effective in reducing the incidence of the disease.

Thalassemia is a group of inherited hemoglobin disorders with defect in the synthesis of hemoglobin chains. 

Case:

The young couple resident in Bandar Abbas,  a 23 year old woman with MCV:63fl; MCH:19; HbA2:3.9  and  a 25 year old man with MCV:94fl; MCH:32; HbA2:2.1; HbF:36, were referred to the Bandar Abbas Medical Genetic & PND Center for genetic counselling before marriage. 

Conclusions:  

A rare CD139 mutation (AAT → GAT) was detected which led to substitution of Asparagine by Aspartic Acid in 139th amino acid in hemoglobin chain and created a hemoglobin variant named Hb Geelong. This is the first report for Hb-Geelong in Iran. It seems that this mutation affects the hemoglobin stability though a non-pathologic process and has a phenotype similar to minor β+ thalassemia.

The purpose of prenatal diagnosis tests is insisting of diagnosis of neonatal disorders, preparing a range of informed choices and making couples at risk to be ready for having children with genetic disorders as well. The aim of this article is to investigate all of the tests in order to determine the best one which has the lowest risk and the highest sensitivity. Screening tests (maternal blood test and ultrasonography for first and second trimester) are testing patients without symptoms who are at low risk. These tests are carried out in the early stages of pregnancy, and the risk of genetic diseases would be estimated. They are safe and also might be helpful in determining whether invasive prenatal genetic tests including chorionic villus sampling, amniocentesis, and percutaneous umbilical blood sampling are needed. Diagnostic test is insisting of invasive tests: amniocentesis, chorionic villus sampling (CVS), cordocentesis, and preimplantation genetic diagnosis (PGD), which is a genetic test on cells removed from embryos to help select the best ones to avoid some of genetic diseases, fluorescence in situ hybridization (FISH), QF-PCR, multiplex ligation probe amplification (MLPA), next generation sequencing (NGS), comparative genomic hybridization (CGH), and non-invasive tests: ultrasound, prenatal sonography, cell free fetal DNA, triple and quadruple screen: alpha fetoprotein (AFP), human chorionic gonadotropin (hCG), unconjugated estriol (uE3), inhibin-A). These tests are intended for patients who have apparent symptoms and the results of their early stages of pregnancy have been positive. Non-invasive prenatal tests (NIPT), sometimes called noninvasive prenatal screening (NIPS), have features of both screening and diagnostic tests, but, now screening test is more considerable. Small fragments of DNA would be analyzed by this testing in which they are circulating in a pregnant woman’s blood. While most DNA is found inside a cell’s nucleus, these fragments are free-floating and not within cells, at this point, they are called cell-free DNA (cfDNA) which usually contain fewer than 200 DNA building blocks (base pairs). Non-invasive prenatal tests is more sensitive with the high degree of specify to determine trisomy 13, 18 and 21 in women who are at increased risk of having offspring with genetic disorders.

Beta thalassemia is a hereditary blood disorder characterized by anomalies in the synthesis of the beta chains of hemoglobin. Chorionic Villus Sampling (CVS) is used for fetal genotyping and as it is an invasive procedure, it has the risk of abortion. As a result, it is desirable to use a noninvasive method instead. The aim of this study was to present a noninvasive method for prenatal diagnosis of &beta-Thalassemia based on pattern of paternal polymorphism.

In this study 30 families with the risk of thalassemia were screened. RFLP pattern of these families were identified and it was possible to investigate the transmission of paternal gene for thalassemia. Whole blood sample was drawn from mothers at gestation weeks 10-12 and their plasma was separated.

A cellular DNA of 7 plasma that contains DNA from both mother and fetus was investigated for RFLP informative sites of beta-globin gene.

Although the amount of fetal DNA in plasma is less than maternal DNA, we could detect specific RFLP pattern of fetus and identified transmission of paternal allele.

Currently, common used methods to obtain fetal material for prenatal diagnosis are potentially dangerous for fetus and mother; this has led to the effort by many groups to develop methods to recover fetal cells by non-invasive means, such as their enrichment from the peripheral blood of pregnant women. The fetal cell types studied by numerous investigators worldwide include fetal leukocytes, i.e. fetal lymphocytes and granulocytes, fetal nucleated red blood cells (NRBCs) and trophoblast cells. Fetal NRBCs have been the most commonly studied cell type, for this reason: the frequency of NRBCs in the fetus early in gestation is relatively high; these cells are also fairly well differentiated and likely to have a limited life span in the maternal circulation and finally, there are specific markers for the enrichment of these cells. However, the fetal cells in maternal blood are rare and a sophisticate technique is required for their enrichment; currently, the most commonly employed techniques are fluorescent activated cell sorting (FACS), magnetic cell sorting (MACS), and charge flow separation. Then, if the fetal cells can eventually be isolated, possible clinical applications will be included screening for fetal chromosome abnormalities via fluorescence in-situ hybridization (FISH) and for gene abnormalities by polymerase chain reaction (PCR).

β -thalassemia is the most common monogenic autosomal recessive all over the world. Therefore, identifying carriers and performing prenatal testing can prevent the birth of a new patient. Case: The young couple resident in Bandar Abbas with their son were referred to the Genetic Laboratory with hematological parameters that indicated minor thalassemia and implicated a symptom of an unknown hemoglobin in the father. Based on the genetic study, the father carried a rare mutation in CD56 (GGC > CGC) leading to Hb-Hamadan. In this study seems that Hb-Hamdan has no pathological effect and. This point is very important particularly in prenatal diagnosis (PND).

In recent years, both alpha and beta thalassemia have been screened in couples before marriage. The severe form of alpha thalassemia, i.e. hydrops fetalis, is found in fetuses and causes fetal death. We tried to determine the need for prenatal diagnosis of hydrops fetalis among couples referred to Alzahra Genetic Laboratory. We also evaluated the cost-effectiveness of alpha thalassemia screening. This descriptive study included all individuals that had been referred to the genetic laboratory from various health centers in Isfahan (Iran). The subjects had mean corpuscular volume less than 80 fL, mean corpuscular hemoglobin less than 27 pg, and hemoglobin A2 less than 2.5. Moreover, one month of iron supplementation had failed to normalize their blood indexes. DNA was duplicated with polymerase chain reaction and examined with gel electrophoresis. During the 27 months and nine days of the study (2009-2012), 642 eligible couples were referred to Alzahra Genetic Laboratory. Of these, 75 couples (11.6%) had beta-beta genotype, 343 couples (53.4%) had alpha-alpha genotype, and 224 couples (34.8%) had genotype alpha-beta. Of the 343 couples who had alpha-alpha genotype, three couples (0.87%) required to have prenatal diagnosis. Considering the very few fetuses that required prenatal diagnosis, the cost-effectiveness of alpha-thalassemia screening in preparing couples for marriage has to be further evaluated at the country level. On the other hand, as fetuses with hydrops will not survive and will abort (only one fetus had hydrops in this study), children with thalassemia major will not be a problem.

In this study, the possibility of prenatal diagnosis of Down syndrome with Real-Time PCR method was evaluated. In this context, optimization of a suitable method for purification of high quality DNA from amniotic fluid samples was also considered. Pregnant women who had the high risk of having babies with Down syndrome were selected according to the biochemical and sonographic data and referred to the amniocentesis center. The DNA of total 59 amniotic fluid samples were extracted with different methods including boiling method, salting out method, Procedures of DNA extraction from Blood and Cell Culture by DNPTM Kit (CinnaGen), Procedure of DNA extraction from cells by DNA Isolation Kit for cells and tissues (Roche), Procedure of DNA extraction from Tissue by MagNa Pure DNA Isolation kit (Roche), and QIAamp DNA Micro Kit (Qiagen). Then, the quality and quantity of the extracted DNA were evaluated by the NanoDrop® ND- 1000 spectrophotometer device. Real-Time PCR reaction using fluorescent dye SYBR Green I (Applied Biosystems, UK) was performed to specifically amplify DSCAM and DYRK1A2 genes and the reference gene (PMP22). Data analysis was performed using comparative cycle threshold method for the determination of the gene dosage and determining the number of copies of chromosome 21. This study showed that DNA extracted from amniotic fluid samples using QIAamp DNA Micro Kit (Qiagen) has the desirable quantity and quality for Real-Time PCR. Specific proliferation of targets and reference genes was achieved and difference between normal and affected groups based on differences between their gene dosages was determined. Prenatal diagnosis of Down syndrome is feasible by the Real-Time PCR method using DNA samples from amniotic fluid cells extracted by QIAamp DNA Micro Kit (Qiagen). The results are comparable to the corresponding results from conventional cytogenetic methods.

FLUORESCENT in situ hybridization has multiple applications in prenatal diagnosis. It can be used for the detection of common chromosome aneuploidies of chromosomes 13,18,21, X and Y it can be used for the early detection of segmental imbalances detected in former affected offspring or resulting from balanced translocations in the carrier parents. FISH is also a useful tool for ruling in/out of mosaicism detected in routine chromosomal study as it will provide a means of screening and scoring a larger number of cells than theoretically possible with routine chromosomal study. In this report we are presenting results of prenatal diagnosis cases where we have employed FISH techniques for direct analysis or for confirmation of results otherwise obtained. In a two year period 60 FISH tests have been performed on fetal samples. Forty five cases were tested for 5 common chromosomes ten of these cases were referred for advanced maternal age, 29 for abnormal marker screening test results, and 6 for history of former offspring with chromosome aneuploidy. The remaining cases were tested for other reasons including 4 for microdeletion syndromes previously detected in other offspring, 4 for mosaicism suspected in routine chromosomal study, and 7 for possible imbalance resulting from known chromosome translocation in either parent. In all cases, the results were confirmed with another technique, most often the results of routine chromosomal study and in microdeletion cases, reanalysis on metaphases prepared from cultured cells. There was 100% correlation between the results obtained from the two techniques. Our experience shows that this technique has the advantage of a speedy result with considerable reliability for use in the detection of specific cases. We recommend the application of FISH for all high risk pregnancies.

Amniocentesis is a technique for detection of chromosomal abnormalities in the unborn fetuses. The technique is being applied to the all high risk pregnancies, mostly in advanced maternal ages and abnormal results in the 1st or 2nd trimester pregnancies. In current situation, first trimester screening is being done in the 11 to 13 weeks and 6 days of gestation, and mid-trimester screening (between weeks 15 to 20). We report the result of our samples in this article. 261 pregnancies were followed and screened by 1st and 2nd trimester screening by Iranian Fetal Foundation protocols in an 18 months period (from January 2007 to July 2008). Advanced maternal ages (35 years and more), or detected a balanced structural chromosomal abnormalities in one of the parents were indications for amniocentesis in this group. Amniocentesis was performed in the 261 cases during the mentioned period. In all of the culture tubes (100%) cell growth was successful. Mean of the time for screening and reporting the results was 12 days. Twelve affected fetuses (4.6%) were detected. The most common abnormalities were Down’s syndrome and balanced translocation. First and second trimester screening is recommended to all pregnancies by international FMF protocol. Whenever the results showed that the pregnancy is prone to the risk then amniocentesis is highly recommended to detect chromosomal abnormalities.

With significant improve in health-care and treatment of infectious diseases, genetic disorders have created a new era of notification. Changes in social attitude towards family life and tendency of parents for limited number of children, sense of responsibility of parents for mental and physical healthiness of children along with their education, needed a new strategy. Since most genetic disorders did not have definitive treatments, physicians tried to prevent these disorders and their disabilities. Early diagnosis of these diseases started in 1934, and first prenatal diagnosis (amniocentesis) was reported in 1967. Rapid progress in cytogenetic and molecular genetic, necessitates each major medical center to have a "prenatal diagnosis department". The first amniocentesis in Iran was done in 1988 with a delay of 20 years. Different problems including no permission for abortion, lack of public knowledge especially authorities and physicians about provided services, and financial limitations of families to afford the expenses of laboratory tests, all were major obstacles to use this technology. Gradually, most of these problems have been solved, and nowadays many centers throughout the country provide these services. In this article, a short list of 15,600 prenatal diagnoses (amniocentesis, chorionic villus sampling, etc) including 13,225 chromosomal abnormalities, 1786 hemoglobinopathies, 283 myopathies, 197 metabolic disorders, 171 triple nucleotide repeats, 32 rare diseases, and eight dermatologic diseases are presented. From 6,473 performed amniocenteses (from 21 February 2007 to 11 April 2009) for evaluation of chromosomal abnormalities, 230 (3.6%) chromosomal abnormalities and 12 (0.2%) unsuccessful responses were documented. In other cases, except for a very few ones who ended in spontaneous abortion, pregnant women continued their pregnancy. Samplings of the amniotic fluid and the placenta were derived by experienced specialties with a very few complications (0.2%), and misdiagnosis was nearly zero.