ABSTRACT
OBJECTIVE@#To establish a newborn screening system for Duchenne muscular dystrophy (DMD) through assessment of MM isoenzyme of creatine kinase (CK-MM) activity.@*METHODS@#The CK-MM level was detected using dry blood spot filter paper from 10 252 male newborns. The results were grouped based on their gestational age, sampling time and intervals between the experiments. The threshold value for CK-MM necessitating genetic testing was determined. Next-generation sequencing (NGS) was carried out for those with a CK-MM value over the threshold, and the result was verified by multiplex ligation-dependent probe amplification (MLPA).@*RESULTS@#Based on the result of non-parametric rank sum test, the median CK-MM concentration has increased with the gestational age, and was inversely correlated with the age of the newborns among unaffected specimens. CK-MM on dry blood spot filter paper can be stable for 14 days at 2-8℃. Statistical analysis of CK-MM value of the 10 252 neonates suggested that the threshold may be set as 700 ng/mL. Exonic deletions were found in 2 confirmed cases, whose CK-MM level was greater than 2000 ng/mL.@*CONCLUSION@#Detection of CK-MM in dry blood spot filter paper has provided an effective method for newborn screening of DMD. This simple and inexpensive method can be used for large-scale screening, which is of great value to the early intervention and treatment of the disease.
Subject(s)
Humans , Infant, Newborn , Male , Dystrophin/genetics , Exons , Multiplex Polymerase Chain Reaction , Muscular Dystrophy, Duchenne/genetics , Neonatal ScreeningABSTRACT
Objective To investigate the effects of growth-discordant twin pregnancies on neonatal thyroid stimulating hormone (TSH) level and congenital hypothyroidism (CH).Methods A total of 3 444 live-birth twin neonates born between January 1,2012 and December 30,2014 in Ningbo City were enrolled.Blood samples via heel puncture were collected and tested.Incidence of CH in singleton and twin neonates was compared.Deviation of birth weight larger than 25％ in twin neonates was set as the criteria for discordant growth.TSH and 17 α-hydroxylase levels in CH twins and normal twins,with or without discordant growth,were compared.Chi-square and non-parametric statistics were performed for data analysis.Results The incidence of CH in twin neonates was 0.56％ (19/3 444),higher than that in singleton neonates [0.09％ (203/225 712),x2=76.225,P＜0.01].Among nineteen CH twins,CH occurred in both twins in eight cases (four twins) and in one of the twins in eleven cases.The gestational age at birth in the eight CH twins were less than 37 weeks,with four males and four females;five were low birth weight infants;one twin were dichorionic,and three twins were monochorionic.In the eleven cases of CH occurring in one of the twins,the gestational age was less than 37 weeks in nine cases,eight were low birth weight infants,six were male and five female;seven were monochorionic and four were dichoronic twins.Five cases of temporary hypothyroidism were all low birth weight infants among the growth-discordant twins.CH cases in growth-discordant group had lower birth weight than their normal twins [M(P25-P75),2 100 (1 800-2 600) vs 2 770 (2 530-2 960) g,Z=4.369],and a higher TSH level [15.4 (11.8-18.5) vs 6.4 (4.8-7.9) mU/L,Z=6.339] (both P＜0.05).In normal twins with or without discordant growth,the neonates with a lower birth weight had a higher TSH level [3.6(2.5-4.7) vs 2.4(1.8-2.9) mU/L,Z=0.962] in weight consistent group,compared with 6.0(4.4-7.8) vs 3.4(1.9-4.1) mU/L in weight inconsistent group (Z=4.369),both P＜0.05.Conclusions In the growth-discordant twins,neonates with a lower birth weight have a higher TSH level and a higher risk of temporary hypothyroidism.
ABSTRACT
Objective To analysis and summary the chromosome abnormal existing in old pregnant women from 2002 to 2013,and to provide basis for clinicians intervene the fetus with chromosome disorders.Methods The 4 539 pregnant women in Ningbo city from 2002 August to 2013 October accepted the fetal karyo type detection,were retrospective analyzed,the frequency of abnormal chromosomal karyotypes was calculated according to different age groups,and the pregnancy outcomes of the old pregnant women were followed up.Thechi-square testswere performed on the frequency dateof the abnormal chromosome karyotype,polymorphism,and serum screening of high risk for fetal chromosome detection of less than 35-years-old pregnant women.Results The total of advanced maternal age pregnancyduring the past 11 years in Ningbo City is 32 080,and the follow-up rate was 99.90％,there are 10 infants borned with chromosomal abnormalities,the 1 290 caseswere detected withadverse pregnancy.A total of 4 539 advanced maternal age pregnancyaccepted amniocentesis,in those we found 107 cases of chromosome abnormality fetus,116 cases of polymorphism.A total of 5 232 high-risk pregnant women accepted the serum screening in the same period (less than 35 years old),finding 135 cases of fetal chromosome abnormal and 69 cases of polymorphism.Conclusion To strengthen the prenatal diagnosis,especially for puerperae above the age of 39,will lower the birth rate of infants with chromosome disease and will be conducive to the high quality of population in Ningbo.
ABSTRACT
Objective To investigate rational management for pregnant women with intermediate risk of Down syndrome (DS) through a retrospective analysis of second trimester maternal screening results for DS.Methods Second-trimester triple maternal serum screening for DS was performed.High risk ( ≥ 1/270) pregnant women received prenatal diagnosis.Intermediate (1/1000 to 1/270) and low (＜1/1000) risk pregnant women received routine obstetric examination.Data of ultrasound diagnosis,karyotype analysis of amniotic fluid and postpartum follow-up were collected.Outcomes of pregnant women were retrospectively analyzed.The incidences of DS among three groups were compared.Data of different groups were compared with Fisher exact or Chi-square test.Results Eighty-six thousand eight hundred and seventy-four pregnant women accepted maternal serum screening and outcomes of 86 126 cases were followed up,among which 4342 cases were DS high risk,8196 intermediate and 73 588 low risk.The incidence of DS was 6.22‰(27/4342) for high risk,0.73 ‰ (6/8196) for intermediate risk and 0.04 ‰ (3/73 588) for low risk group.The incidence of DS was higher in high risk group than in intermediate risk group (Fisher exact probability,P=0.000),and was higher in intermediate risk group than in low risk group (Fisher exact probability,P=0.000).Comparison among the three subgroups within intermediate risk group showed no significant differences (x2 =0.047,P =0.977).Conclusions Pregnant women with intermediate risk of DS should be paid more attention.Reasonable management such as ultrasound diagnosis and prenatal consultation should be provided.