Cardiovascular malformations in Malaysian neonates with Down's syndrome

A prospective study was done to determine the incidence of cardiovascular malformations in neonates with Down's syndrome. 17/34 (50%) of the babies with Down's syndrome born at the Maternity Hospital, Kuala Lumpur, Malaysia had congenital heart defects. These included 7 cases of ventricular septal defect (VSD), 3 cases of patent ductus arteriosus (PDA), 2 cases of atrio-ventricular canal defect, 2 cases of ventricular septal defect with patent ductus arteriosus, 1 case of hypertrophic cardiomyopathy, 1 case of hypertrophic obstructive cardiomyopathy and 1 case of complex cyanotic heart. Only 8/17 (47%) of these babies had any clinical signs suggesting underlying cardiac defects. In view of the common occurrence of cardiac anomalies, it is recommended that echocardiographic screening should be carried out on all neonates with Down's syndrome.     

Down's syndrome in South Australia.

In a survey of Down's syndrome in South Australia, 921 persons, both living and deceased, were identified; 717 individuals with the disorder were living in South Australia. Cytogenetic confirmation of the diagnosis had been made in 774 cases. From 1955 to 1977, the over-all incidence of Down's syndrome at birth was found to be 1.175/1000 live births. The incidence of Down's syndrome was significantly lower over the last five years of this period than for the first 18 years; thus it appears that the incidence of Down's syndrome in South Australia is falling. Analysis of maternal age changes with time has not revealed any changes to the maternal age-specific rates for Down's syndrome, although the rate for mothers aged 25 years or younger appears to be falling. The proportion of Down's syndrome babies born to women aged 35 years or more has decreased from 65.7% for those born before 1950 to 30.4% for those born from 1975 to 1977; similarly, the median maternal age has fallen from 37.12 years to 28.25 years. Regression analyses of maternal age rates for Down's syndrome by single years have produced figures suitable for genetic counselling. A plea is made that Down's syndrome should become a notifiable condition.     

Congenital talipes in Malaysian neonates: incidence, pattern and associated factors

A study was carried out on 8,369 neonates delivered in the Maternity Hospital, Kuala Lumpur over a period of four months. Forty-nine neonates (5.6 per 1000 livebirths) had congenital talipes. The incidence of congenital talipes equinovarus (CTEV) was 4.5 per 1000 livebirths while that of congenital talipes calcaneovalgus (CTCV) was 1.3 per 1000 livebirths. 6/11 (54.5%) of the CTCV was unilateral, the ratio of right to left feet involvement being 1:1. Only 12/38 (31.5%) of the CTEV were unilateral, the ratio of right to left feet involvement being 1:2. Congenital talipes was significantly more common in the low birthweight neonates (p less than 0.001). However, the condition was not significantly more common in neonates with breech presentation nor in those born to primigravida mothers. Our data suggested that multifactorial genetic background as the most likely underlying cause of congenital talipes in Malaysian neonates.     

Subaponeurotic haemorrhage in Malaysian neonates

In a 30-month prospective study, between January 1987 and June 1989, 101 of 64,424 Malaysian neonates (1.6 per 1000 livebirths) born in the Maternity Hospital, Kuala Lumpur were found to have subaponeurotic haemorrhage shortly after delivery. The incidence was highest in neonates weighting 4000 gm or more. There was no significant difference in incidence of this condition in neonates of different ethnic origins. Hypoprothrombinemia was present in only 5/101 (5.0%) of the affected neonates. Sixty seven (66.3%) of the neonates with subaponeurotic haemorrhage had history of trial of vacuum extraction. The incidence of subaponeurotic haemorrhage was significantly higher in neonates delivered by vacuum extraction than by other modes of delivery in this hospital (41.4 per 1000 livebirths in neonates delivered by vacuum extraction versus 1.0 per 1000 livebirths in neonates delivered by other modes). Those neonates who developed subaponeurotic haemorrhage without trial of vacuum extraction had a history of either prolonged labour or difficult delivery. Thirty-three (32.7%) of the neonates with subaponeurotic haemorrhage developed anaemia which required blood transfusion and 3/33 (9.1%) were in shock. Fifty seven (56.4%) of the neonates with subaponeurotic haemorrhage developed hyperbilirubinemia due to the haemorrhage. Four (7.0%) of them had severe unconjugated hyperbilirubinemia which required exchange transfusion. The results of this study suggest that subaponeurotic haemorrhage in Malaysian neonates was commonly associated with vacuum extraction and was not a benign condition.     

A study of cleft lip and palate in neonates born in a large Malaysian maternity hospital over a 2-year period

Out of 52,379 babies delivered in the Maternity Hospital, Kuala Lumpur, over a 2-year period, 64 were born with cleft lip and/or palates. The rate of occurrence of cleft was 1.24 per 1000 livebirths or 1.20 per 1000 deliveries. The Chinese babies had the highest incidence (1.9 per 1000 deliveries) while the Malays had the lowest (0.98 per 1000 deliveries). The most common type was unilateral cleft of the primary and secondary palates. Among the Indian babies, cleft of the secondary palate was most common. 18.8 percent of all the affected babies had positive family history of cleft. 10.9% of the mothers of affected babies had positive history of drug ingestion especially Chinese herbs during pregnancy. Associated congenital abnormalities occurred in 15.6% of the babies with cleft lip and/or palate.     

孕中期唐氏综合征血清学筛查的经济效益评价

目的 从临床及卫生经济学的角度探讨孕中期唐氏综合征产前筛查的意义.方法 采用酶联免疫吸附试验(ELISA)检测12 720名孕龄为14～20周的中国孕妇的血清甲胎蛋白(AFP)、绒毛膜促性腺激素(β-hCG)水平,结合孕妇的年龄、孕周等关键参数,计算唐氏综合征的风险系数,并对高危人群进行产前诊断.结果 761例唐氏综合征筛查高危妊娠妇女中,诊断唐氏综合征患儿7例;11 959例唐氏综合征筛查低危妊娠妇女中,诊断唐氏综合征2例.筛查成本为495 023元,安全指数为0.28.结论 采用ELISA法检测孕妇血清AFP和β-hCG的方法成本低、安全性高,是适合中国国情的唐氏综合征产前筛查方案.     

In-vitro fertilisation and neonatal ventilator use in a tertiary perinatal centre.

OBJECTIVE: To determine the contribution of livebirths resulting from in-vitro fertilisation and related technologies (IVF) to the use of neonatal ventilator beds. DESIGN: A retrospective review of records of all livebirths from our hospital's IVF program and all IVF infants receiving mechanical ventilation in our neonatal intensive care unit for the period 1985-1989. We also reviewed records of labour ward deliveries, neonatal intensive care unit admissions and transfer requests in order to obtain comparative data for livebirths of non-IVF infants whose mothers had been booked to deliver in our hospital. SETTING: A tertiary perinatal centre with a large IVF program and a Level 3 neonatal intensive care unit. RESULTS: IVF livebirths accounted for 5.1% of total ventilator bed days. Compared with non-IVF booked livebirths, IVF babies were more likely to require ventilation (odds ratio, 7.41; P less than 0.0001) and used more ventilator bed days per 100 livebirths (rate ratio, 9.63; P less than 0.0001), largely due to preterm delivery of multiple pregnancies; 42.3% of IVF babies who required ventilation were from triplet births and 38.5% from twin births. Nevertheless, even IVF singletons used more ventilator bed days per 100 livebirths than non-IVF booked livebirths (rate ratio, 2.78; P less than 0.0001). IVF livebirths accounted for 9.9% of the 78% increase in ventilator bed days used in 1989 compared with 1985. CONCLUSIONS: IVF livebirths accounted for only a small percentage of the overall use of neonatal ventilator beds, but consumed relatively more of such resources per livebirth than did non-IVF livebirths. The degree of risk of requiring ventilation is directly related to the number of infants in a multiple pregnancy, but even IVF singletons are at a relatively high risk of requiring ventilation.     

Screening for Down's syndrome in the North East Thames region

The suggested strategies for a screening programme for Down's syndrome by maternal serum alpha fetoprotein concentration were examined and tested on the experience of the North East Thames Regional. Screening by maternal serum alpha fetoprotein concentration may be used to identify pregnancies at increased risk, but this is useful only in women aged over 32 whose collective risk is greater than one in 200. The absolute probability of carrying babies with Down's syndrome for individuals in this high risk group can then be calculated and used to decide whether further diagnosis by amniocentesis is desired.     

The prevention of Down's syndrome in the south western region of England 1975-1985

Cytogenetic prenatal screening for Down's syndrome in the South West Region of England from 1975 to 1985 was reviewed. The use of amniocentesis increased, and for the years 1981 to 1985 averaged 29.4% of women 35 years or over at their estimated date of delivery. 58 pregnancies were terminated after karyotyping of amniotic fluid cells confirmed trisomy 21. 385,440 live births were born in the region, 452 with Down's syndrome, giving a live birth incidence of 1 in 853. The effective impact of prenatal screening was calculated at an overall 8.3% reduction in Down's syndrome live births, but for the years 1981 to 1985 this rose to 11.3%. In spite of the introduction of new prenatal screening programmes that are not reliant solely on maternal age, it is predicted that substantial numbers of children with Down's syndrome are likely to be born each year. Adequate medical facilities will still be required for the survivors.     

Consanguinity, non-disjunction, parental age and Down's syndrome

The effect of consanguinity on the non-disjunction mechanism in Down's syndrome, was examined in 417 cytogenetically confirmed Down's syndrome patients. The incidence of parental and grandparental consanguinity was 17.5% (n = 73), while that of only parental consanguinity was 17.2% (n = 71). First cousin marriages occurred more frequently, than uncle-niece and 2nd cousin marriages. With regard to parental age, only the mean age difference between consanguineous couples significantly differed from non-consanguineous couples. The inbreeding coefficient did not differ between trisomy 21 and translocation Down's families. From this study, it is concluded that consanguinity does not predispose to Down's syndrome.     

Epidemiology of necrotising enterocolitis in Malaysian neonates

Over a 21-month period, 108 of 45,770 neonates born in the Maternity Hospital, Kuala Lumpur, developed necrotising enterocolitis (NEC). The incidence of NEC was 2.4 per 1000 livebirths or 2.7 per 100 special care nursery (SCN) admissions in this Hospital. There was no significant difference in the incidence between the sexes or among the different races. NEC was most common (9.4%) in the very low birthweight (VLBW: neonates weighing less than 1500 grams) and the preterms of less than 34 week gestation (8.4%). 54.6% of the patients developed the condition during the first week of life. NEC occurred throughout the year in our nursery with clustering of cases intermittently. The case fatality ratio of the condition was 28.7%. NEC accounted for 5.7% of our Hospital's neonatal (less than 28 days of life) and postneonatal (greater than or equal to 28 days of life) deaths. There was no significant difference in the rates of occurrence of placental praevia, prolonged rupture of amniotic membranes, maternal pregnancy-induced hypertension, birth asphyxia, apnoea, respiratory distress, patent ductus arteriosus and exchange blood transfusion in neonates with NEC and those in the control group. Our findings on Malaysian neonates were comparable with those reported in the literature on neonates in developed countries.     

A study of 8 year neonatal deaths (1982-1989) of Toa Payoh Hospital

A study of 233 neonatal deaths out of 30910 livebirths over an 8 year period in the Toa Payoh Hospital is done. The Hospital has since ceased providing obstetric and neonatal intensive services from April 1990 due to restructuring of hospital care. The Neonatal Mortality Rates (NNMR) from 1982-1989 ranged from 6.52 to 9.55 and there was no significant fall in trend (p = 0.13). One hundred and thirteen (48.5%) neonates who died were below 1500gm (VLBW). Various causes of neonatal deaths were examined and there was a decline in respiratory distress syndrome (RDS) death rates (p less than 0.0002). Deaths due to asphyxia (p greater than 0.05) and infections (p greater than 0.05) have not declined significantly over the same period. It is also observed that less VLBW babies died over this 8 year period and the VLBW mortality rates (p less than 0.02) have declined. However, the congenital malformation mortality has also not declined significantly (p = 0.92) though early study (1972-1981) showed an increasing trend of malformation deaths among total neonatal deaths (p less than 0.02). Improvement in VLBW and RDS management has not contributed to a significant decline in NNMR. It is observed that more VLBW babies were born during this 8 year period (p = 0.01) especially so in the less than 1000 gm group (p = 0.0005) and the survival of VLBW babies has improved (45.5% to 75.8% alive) as a result of advances in neonatal intensive care. The reasons for increase in incidence of VLBW births in the past few years are not known.(ABSTRACT TRUNCATED AT 250 WORDS)     

Molecular diagnosis of Down’s syndrome

Objective To establish a new diagnostic method for Down’s syndrome using polymerase chain reaction (PCR).Methods DNA extracted from five healthy individuals and five Down’s syndrome patients was amplified in six specific tetranucleotide repeat loci on chromosome 21 using PCR. An accurate diagnosis was made by analyzing allelic distribution at each locus. Results All Down’s syndrome patients were identified as having at least two loci with three alleles, while none of the healthy individuals had three alleles. In addition, when two alleles were identified for a particular locus in the Down’s syndrome samples, it was more likely that the intensity ratio between the two alleles was close to 2∶1. Conclusion The molecular method can provide a fast, accurate, and economical alternation for the traditional cytogenetic diagnostic method for Down’s syndrome.     

A 2-year study of neonatal mortality in a large Malaysian hospital

A 2-year study was carried out in the Maternity Hospital, Kuala Lumpur to determine the neonatal mortality rates. This Hospital functions both as the local service centre as well as the national referral centre in Malaysia. Its neonatal services, however, were equipped and manned at those below Level III perinatal centre. During the study period 52, 877 livebirths took place in the Hospital. In 1987 and 1988 respectively, the low birthweight (less than 2500 gm) rates were: 112.8 and 101.9 per 1000 livebirths, very low birthweight (less than 1500 gm) rates: 11.1 and 8.8 per 1000 livebirths, neonatal mortality rates: 12.5 and 10.7 per 1000 livebirths and neonatal mortality risk ratio: 1.15 and 1.27. There was significant difference in mortality rates among the Malay, Chinese and Indian babies born in this hospital: the Indians had the highest and the Chinese the lowest rates. Babies delivered by breech or lower segment Caesarean section (LSCS) also had significantly higher mortality than those delivered by other modes of delivery. Low birthweight neonates constituted less than 45% of the total special care nursery admission but contributed to more than 70% of the total neonatal deaths. The common causes of neonatal deaths were problems of prematurity, infection, asphyxia and congenital malformations. Preterm and low birthweight neonates died primarily from problems of prematurity or infection. Term and larger neonates died mainly from asphyxia. More than 75% of the neonatal deaths occurred before 7 days of life. Improvement of antenatal care in the community and upgrading of perinatal services in this Hospital could help to lower the morbidity and mortality due to preventable causes.     

High frequency of mitral valve prolapse and aortic regurgitation among asymptomatic adults with Down's syndrome

Although cardiac anomalies are well documented among children with Down's syndrome, data on the cardiac status of adults with Down's syndrome are sparse. Therefore, we performed cardiac auscultation and Doppler echocardiographic examinations in 35 asymptomatic adults with Down's syndrome. There were 25 men and ten women; their mean age (+/- SD) was 26 +/- 8 years. Only ten subjects (29%) had normal findings on examination. The most frequent abnormal findings were holosystolic mitral valve prolapse (MVP) in 20 subjects (57%) and mild aortic regurgitation in four subjects (11%). Of the 20 subjects with MVP, five had associated tricuspid valve prolapse, but none had notable mitral regurgitation. Thus, we found that the majority of asymptomatic adults with Down's syndrome had valvular heart abnormalities. The high frequency of MVP and aortic regurgitation suggests that these lesions may be specifically associated with Down's syndrome in adults.     

Down's syndrome. Recent trends in the United States

The crude incidence of Down's syndrome (DS) in the United States is currently about 1/1,000 births. Reduction in the proportion of births to women 35 years and older can account for a halving of the estimated percentage of DS births to this age group and a drop in the estimated crude incidence of DS from 1.33/1,000 births in 1960 to 0.99/1,000 births in 1978. Epidemiologic studies suggest that among women 35 years and older, the risk of having a child with DS has not changed. With the present distribution of maternal ages, prenatal diagnosis among women 35 years and older can result in no more than a 20% decrease in the crude incidence of DS. With continued use of prenatal diagnosis among older gravidas, upward of 80% of DS births will occur to younger mothers.     

母血清生化二联、三联标记物筛查胎儿唐氏综合征

目的 用母血清生化标记物筛查胎儿唐氏综合征(Down’s syndrome,DS)等先天异常。方法 应用孕妇血清指标和时间分辨荧光免疫分析法对本院1996年11月-2001年3月在本科产前检查的2886例孕妇进行DS胎儿筛查。对高危孕妇作羊腹腔穿刺或早孕绒毛取材以得到胎儿染色体。对应用的指标捡出率及假阳性率进行分析。结果 共捡出11例DS,8例无脑儿;DS检出率3．8‰。结论 妊娠相关血浆蛋白A(PAPP-A)筛查胎儿DS有很好的价值并能使产前诊断时期提前,甲胎蛋白 游离人绒毛膜促性腺激素(AFP freeβ-HCG)可用于检测DS和胎儿异常。     

Septic arthritis in the newborn--a 17 years' clinical experience

Septic arthritis is an uncommon, yet serious disorder in the newborn. Most patients survive with permanent handicaps. We encountered 11 cases of neonatal septic arthritis in the Hospital over the past 17 years (1971-87), an incidence of 0.12 per 1000 livebirths or 0.67 per 1000 admissions to the neonatal nursery. The clinical experience is presented. The diagnosis of septic arthritis in the newborn is more difficult than in the older children. Joint swelling (10/11), tenderness (9/11) and limitations of joint movement (8/11) were the common presenting clinical signs. Constitutional symptoms (fever, leucocytosis, gastrointestinal disturbances) were unremarkable. More than half of the babies (6/11) were prematurely born. The knees and the hips were frequently infected, many had multiple joint involvement (6/11). Septic arthritis commonly manifested between 20-40 days of life. The causative agents viz. Staphylococcus aureus (4/11), Candida (2/11), Citrobacter (1/11) and Methicillin Resistant Staphylococcus aureus MRSA (4/11) showed that septic arthritis was a nosocomial infection. Many babies (9/11) had insertion of intravascular catheter for 1-3 weeks and 9/11 babies had concomitant positive blood culture, 2/11 coexisting osteomyelitis and 1, meningitis. Though there was no death, majority of the babies had joint destruction and severe handicap. Early diagnosis including frequent examinations of joints, prompt treatment and control of nosocomial infection are important in management.     

Down''s syndrome in British Columbia Indians

An investigation into the incidence of Down's syndrome in British Columbia Indians disclosed that this was little different from that in the non-Indian population. The clinical features of the condition are common to both groups.     

唐氏综合征筛查指标MoM值的正态性研究

目的: 考察江苏唐氏综合征产前筛查指标AFP和HCG的MoM值的正态性,探索Johnson分布体系中的SL分布族在上述指标正态性转换中应用的可行性和有效性. 方法: 资料来自于江苏省出生缺陷干预项目研究,采用对数正态和Johnson分布体系中的SL正态性转换方法. 结果: 两指标的MoM值均不服从正态分布;对数MoMHCG值以样本均数和标准差作为参数时,指标AFP的正态性较好,HCG仍不服从正态;Z=0.31时MoM指标SL转换后正态性明显改善. 结论: Johnson分布体系中SL分布族在我国唐氏综合征产前筛查指标HCG的MoM值的正态性转换中具有一定的应用价值.