Survival in trisomy 18. Life tables for use in genetic counselling and clinical paediatrics

Prevalence and clinical characterization of oral clefts in patients with chromosome trisomy 18

OBJECTIVE

To verify the prevalence and perform the clinical characterization of oral clefts in a sample of patients with trisomy of chromosome 18 in Southern Brazil.

METHODS

This was a retrospective cross-sectional study, performed in a reference clinical genetic service in Southern Brazil. The initial sample consisted of 77 patients diagnosed in the neonatal period with trisomy 18 treated at the Clinical Genetics Service of a referral hospital at Federal University of Health Sciences of Porto Alegre (UFCSPA). The patients' diagnosis was confirmed by karyotype and care was provided during their stay in the intensive care unit (ICU) of the hospital that is a reference in Southern Brazil for care for malformed patients. The period covered was from 1975 to 2020.

RESULTS

During the study period, 77 patients diagnosed with trisomy 18 were treated, most of them in the ICU. Of these, 13 individuals were excluded due to incomplete data. The final sample consisted of 64 patients with an average age of 2.4 years of life, ranging from one day to 16 years old, the majority of whom were female. Regarding face dysmorphisms identified in the sample, three (4,68%) patients had cleft lip and two (3,11%) had cleft lip and palate.

CONCLUSIONS

This study contributed to the recognition of the characteristics and prevalence of oral clefts in individuals with trisomy 18 in a sample of patients from Southern Brazil. In addition, we described the clinical alterations found in patients with oral clefts, as well as other associated comorbidities, such as cardiac, neurological and pulmonary comorbidities, as well as cranial and facial dysmorphisms.

Seizures in trisomy 18: Prevalence, description, and treatment

Changes in medical intervention over the last decade have improved outcomes for individuals with trisomy 18, the second most common human aneuploidy syndrome at birth. As children with trisomy 18 live longer, a shared concern of medical experts and parents is the occurrence and treatment of seizures. Previously published surveillance guidelines for this condition have not addressed seizure management. Using parent-reported data collected as part of the Tracking Rare Incidence Syndromes project, we report on the prevalence, course, and management of seizures in individuals with trisomy 18. Twenty-eight percent (52/186) of individuals diagnosed with trisomy 18 in our retrospective cohort experienced generalized, focal, or mixed seizures at some point in their lifetime. For many individuals, seizures were effectively managed by broad-spectrum anti-seizure medications. Correlation analysis showed that focal and generalized seizures were more likely to occur in individuals who had previously experienced infantile spasms or central apnea. Electroencephalogram testing should be considered as part of a standard screening approach in individuals with trisomy 18 to enable early diagnosis and treatment of seizures. An international registry that incorporates parent-reported and clinical data for patients with trisomy 18 may facilitate ongoing research and recruitment into clinical trials for seizure management.

A visual tool inclusive of fetal ultrasound and autopsy findings to reach a balanced approach to counseling on trisomy 18 in early second trimester

Identified by the eponym "Edwards' Syndrome," trisomy 18 (T18) represents the second most common autosomal trisomy after T21. The pathophysiology underlying the extra chromosome 18 is a nondisjunction error, mainly linked with the advanced maternal age. More frequent in female fetuses, the syndrome portends high mortality, reaching a rate of 80% of miscarriages or stillbirths. The three-step evaluation includes first trimester screening for fetal aneuploidy using a combination of maternal age, fetal nuchal translucency thickness, fetal heart rate and maternal serum free ß-hCG and PAPP-A; followed by the research for fragments of fetal DNA in maternal blood; and, finally, invasive techniques leave to the established diagnosis. Starting with the first trimester scan, selected ultrasound findings should be investigated to define not only the impact of the genetic problem on the fetus, but also to address the prenatal counseling. Previous series underline that T18 is not uniformly lethal. An active dialogue on the choices in the management of infants with T18 has emerged, sustained by the transition from the comfort care to the intervention attitude. Survival rates for individuals with supposedly fatal conditions have increased. In this novel scenario, an ad hoc counseling is pivotal. To support it, a comparative analysis by pictorial assays between ultrasound and autopsy findings could be beneficial. We provide an illustrative tool from a clinical case managed in early second trimester, with the purpose to strive a balanced approach in the hard choice faced by couples of fetuses with T18.

Survival Outcomes of Two-Stage Intracardiac Repair in Large Ventricular Septal Defect and Trisomy 18

BACKGROUND

Surgical management has not been encouraged in patients with trisomy 18 (T18) and congenital heart diseases due to poor survival. This study aimed to investigate (1) the appropriateness of palliative surgeries followed by intracardiac repair (ICR) (i.e., two-stage ICR) for patients with a large ventricular septal defect (VSD) and T18, and (2) its impact on their long-term outcomes.

METHODS

Medical charts of patients with VSD and T18 who underwent two-stage ICR at the Japanese Red Cross Medical Center between January 2005 and December 2019 were retrospectively reviewed. Demographic data, timing, and types of palliative surgeries, information related to ICR, peri- and postoperative clinical information, postoperative survival, and cause of death were collected. The long-term prognosis of patients treated with two-stage ICR was compared with that of patients treated with primary ICR and palliative surgery without ICR.

RESULTS

Overall, 18 (2 male, 16 female) patients underwent two-stage ICR. Pulmonary artery banding was the initial palliative surgery in all patients after a median duration of 19.5 (range 6-194) days of life. The median age and the mean body weight at the time of ICR were 18.2 (7.6-50.7) months and 6.0 ± 1.0 kg, respectively. The mean pulmonary artery pressure and pulmonary vascular resistance index before ICR were 19.1 ± 7.3 mmHg and 3.4 ± 2.0 U m², respectively. Overall, 17/18 (94%) patients were discharged after ICR. Fourteen (78%) patients were alive during data collection. None of the patients died of cardiac insufficiency, and the median duration of survival was 46.3 (14.3-186.4) months since birth. Most patients required cardiac medications rather than pulmonary vasodilators at the last follow-up. During the study period, three patients underwent primary ICR, and 46 underwent palliative surgery without ICR. Of those who underwent primary ICR, two died in the hospital on the first and 48^th day following ICR, and the third died 179 days after the ICR. The Log-rank test revealed a significantly longer survival for the patients treated with two-stage ICR compared with those treated with palliative surgery without ICR (P = 0.003).

CONCLUSION

Two-stage ICR improves the long-term survival of patients with VSDs and T18. This safe surgical strategy can also prevent pulmonary hypertension in such patients.

Prenatal counseling and parental decision-making following a fetal diagnosis of trisomy 13 or 18

OBJECTIVES

To evaluate parental decisions following a prenatal diagnosis of trisomy 13 (T13) or trisomy 18 (T18), prenatal counseling received, and pregnancy outcomes.

STUDY DESIGN

Single-center, retrospective cohort study of families with a prenatal diagnosis of T13 or T18 from 2000 to 2016.

RESULTS

Out of 152 pregnancies, 55% were terminated. Twenty percent chose induction with palliative care, 20% chose expectant management, 2% chose full interventions, and 3% were lost to follow-up. Counseling was based on initial parental goals, but most women were given options besides termination. Women who chose expectant management had a live birth in 50% of the cases. Women who chose neonatal interventions had a live birth in 100% of the cases, but there were no long-term survivors.

CONCLUSIONS

The majority of women who continue their pregnancy after a fetal diagnosis of T13 or T18 desire expectant management with palliative care. A live birth can be expected at least half of the time.

Major anomalies and birth-weight influence NICU interventions and mortality in infants with trisomy 13 or 18

OBJECTIVE

To describe neonatal intensive care unit (NICU) medical interventions and NICU mortality by birth weight and major anomaly types for infants with trisomy 13 (T13) or 18 (T18).

STUDY DESIGN

Retrospective cohort analysis of infants with T13 or T18 from 2005 to 2012 in the Pediatrix Medical Group. We classified infants into three groups by associated anomaly type: neonatal surgical, non-neonatal surgical and minor. Outcomes were NICU medical interventions and mortality.

RESULTS

841 infants were included from 186 NICUs. NICU mortality varied widely by anomaly type and birth weight, from 70% of infants <1500 g with neonatal surgical anomalies to 31% of infants ⩾2500 g with minor anomalies. Infants ⩾1500 g without a neonatal surgical anomaly comprised 66% of infants admitted to the NICU; they had the lowest rates of NICU medical interventions and NICU mortality.

CONCLUSIONS

Risk stratification by anomaly type and birth weight may help provide more accurate family counseling for infants with T13 and T18.

Effectiveness of cardiac surgery in patients with trisomy 18: a single-institutional experience

BACKGROUND

Surgical repair for cardiac lesions has rarely been offered to patients with trisomy 18 because of their very short lifespans. We investigated the effectiveness of cardiac surgery in patients with trisomy 18. Patients and methods We performed a retrospective analysis of 20 consecutive patients with trisomy 18 and congenital cardiac anomalies who were evaluated between August, 2003 and July, 2013. All patients developed respiratory or cardiac failure due to excessive pulmonary blood flow. Patients were divided into two subgroups: one treated surgically (surgical group, n=10) and one treated without surgery (conservative group, n=10), primarily to compare the duration of survival between the groups.

RESULTS

All the patients in the surgical group underwent cardiac surgery with pulmonary artery banding, including patent ductus arteriosus ligation in nine patients and coarctation repair in one. The duration of survival was significantly longer in the surgical group than in the conservative group (495.4±512.6 versus 93.1±76.2 days, respectively; p=0.03). A Cox proportional hazard model found cardiac surgery to be a significant predictor of survival time (risk ratio of 0.12, 95% confidence interval 0.016-0.63; p=0.01).

CONCLUSIONS

Cardiac surgery was effective in prolonging survival by managing high pulmonary blood flow; however, the indication for surgery should be carefully considered on a case-by-case basis, because the risk of sudden death remains even after surgery. Patients' families should be provided with sufficient information to make decisions that will optimise the quality of life for both patients and their families.

Sonographic Findings in Trisomy 18

Trisomy 18 is the second most common trisomy syndrome. Sonographically, trisomy 18 syndrome can present with a wide range of fetal anomalies. The specific anomalies discussed in this report include choroid plexus cysts, agenesis of the corpus callosum, cleft lip, micrognathia, cystic hygroma, cardiac defects, diaphragmatic defects, omphalocele, spinal defects, and extremity defects. Knowledge of the abnormalities associated with trisomy 18 enhances the sonographer's ability to recognize this phenomenon when encountered.

Love and the Value of Life in Health Care: A Narrative Medicine Case Study in Medical Education

This case study is an example of narrative medicine applied to promote self-awareness and develop humanistic contents in medical education. The impact and the human appeal of the narrative lie in the maturity and empathy shown by a student when reporting his dramatic experience during the care given to a newborn (with Patau syndrome and multiple malformations diagnosed at birth) and to her mother. The narrative approach helped the student to be successful in bringing out the meaning behind the story and to position himself from the mother's and newborn's perspective. The student's introspection changed a seemingly scary interaction into a positive experience, overcoming many initial negative emotions, such as fear, disappointment, horror, hopelessness, and insecurity in the face of the unexpected. It is uplifting how the student was strengthened by the power of maternal love to the point of overcoming any remaining feelings of eugenics or rejection. Other important lessons emerging from the case study were the art of listening and the value of silence. This narrative shows how the development of narrative competence can help establish a good physician-patient relationship, because the physician or the student with such competence usually confirms the patient's value and demonstrates concern for them, focusing on what they say and allowing genuine contact to be established, which is necessary for effective therapeutic alliance. The student's interpretations of the meaning of love and value of life inspired him on his reframing process of a medical practice marked by vicarious suffering.

Clinical features and survival in individuals with trisomy 18: A retrospective one-center study of 44 patients who received intensive care treatments

Trisomy 18 syndrome is a common autosomal aneuploidy chromosomal abnormality caused by the presence of extra chromosome 18 that leads to malformations of various parts of the body. In this study, we retrospectively investigated the effect of the medical progression and prognosis of 44 cases of trisomy 18, admitted to our neonatal intensive care unit between 1992 and 2013. The patients were divided into group A (n=20, 1992‑2002) and group B (n=24, 2003‑2012). Following delivery, karyotype, gender, gestational weeks, birth place, cesarean section, Apgar score and birth weight were analyzed using the Fisher's exact test, unpaired t‑test and Mann‑Whitney U test. Based on the statistical results, a comparison was made of the two groups and no significant differences were observed. Clinical data of major complications, mechanical ventilation, discharge from hospital and survival days were reviewed for the cases of trisomy 18. Of the 44 patients, 42 had cardiac anomaly, 16 had esophageal atresia, and 3 patients had brain anomaly. Ventilation treatment was performed in 29 cases (65.9%) and an increased percentage was identified in group B patients. The percentage survival was estimated using Kaplan‑Meier curves and the two groups were analyzed using the generalized Wilcoxon test. Improvement in life prognosis was observed in group B as compared to group A. The log‑rank test was used to assess survey periods of 180 days, 1 year, and the entire observation period. Although significant differences were observed for the prognosis of trisomy 18 at 180 days after birth, after 1 year and the entire survey period after birth, the significant differences were not confirmed. In conclusion, results of the present study provide information concerning genetic counseling for parents/guardians and life prognosis, prior to applying intensive management to newborns with trisomy 18.

Fetal outcome of trisomy 18 diagnosed after 22 weeks of gestation: Experience of 123 cases at a single perinatal center

To investigate the pregnancy outcome of the fetuses with trisomy 18, we studied 123 cases of trisomy 18 who were born at our hospital from 1993 to 2009. Among them, 95.9% were diagnosed with trisomy 18 prenatally. Prenatal ultrasound findings showed fetal growth restriction in 77.2%, polyhydramnios in 63.4% and congenital heart defects in 95.1%. For 18 cases, cesarean section (C-section) was chosen, and for 75 cases, transvaginal delivery was chosen. Premature delivery occurred in 35.5%. Stillbirths occurred in 50 cases (40.7%). Fetal demise before onset of labor occurred in 30 cases and fetal demise during labor occurred in 20 cases which was 26.7% of vaginal deliveries. Among the 73 live-born infants, the survival rate for 24 h, 1 week, 1 month and 1 year were 63%, 43%, 33% and 3%. The median survival time was 3.5 days. There was no significant difference between the survival time of C-section and that of vaginal delivery. However, for the births involving breech presentation, the survival time of C-section was significantly longer than that of vaginal delivery. When the fetus is diagnosed with trisomy 18, the parents have to make many choices. These findings constitute critical information in prenatal counseling to the couples whose fetuses have been found to have trisomy 18, especially when they choose palliative approaches in the perinatal management.

Differences in mortality and morbidity according to gestational ages and birth weights in infants with trisomy 18

The aim of this study was to clarify the effects of gestational age and birth weight on outcomes of the infants. Medical records of 36 infants with trisomy 18 admitted to Tokyo Women's Medical University Hospital from 1991 to 2012 were reviewed retrospectively. We compared clinical characteristics between term infants (n = 15) and preterm infants (n = 21). There were one very-low-birth-weight (VLBW) term infant (5%) and 12 VLBW preterm infants (80%). Although there were no significant differences in clinical characteristics and provided management between the two groups, none of the preterm infants achieved survival to discharge. On the other hand, 6 of 21 term infants (29%) achieved survival to discharge (P < 0.05). Similar results were obtained for comparisons between the VLBW infants and non-VLBW infants. Multiple logistic regression analysis revealed that shorter gestational age had a more negative impact than lower birth weight to survival to discharge in infants with trisomy 18. In both preterm and term groups, the infants who died before 30 days commonly died of respiratory failure or apnea. Whereas, the infants who survived more than 30 days mostly died of heart failure.

Parental counseling in trisomy 18: Novel insights in prenatal features and postnatal survival

Data on the outcome of trisomy T18 (T18) when diagnosed during pregnancy are lacking. We performed a retrospective study of pregnancies complicated by T18 diagnosed at our center and a literature search for publications on the topic, with pooled estimates of survival rates at different gestational and post-natal ages. In our series, all the 60 patients included in the analysis had prenatally detected ultrasound anomalies, which were evidenced in the first trimester or at the second trimester scan in 73% of cases. In the continued pregnancies, ultrasound findings did not correlate with prenatal or post-natal outcome. A meta-analysis of available literature and our data showed that 48% [37-60%] of fetuses were live born, and among these 39% [11-72%] survived beyond 48 hr and 11% [3-21%] beyond 1 month. Our results confirm that prenatal ultrasound has high sensitivity in detection of T18 but is not predictive of the outcome of the continued pregnancies. The data on survival support that T18, even when antenatally diagnosed, cannot be considered as a uniformly lethal syndrome.

When Cri du chat syndrome meets Edwards syndrome

It has been well established that the 5p deletion causes Cri du chat syndrome, typically characterized by a cat‑like cry, and that duplication of 18q causes Edwards syndrome; the two are rare genetic abnormalities that separately lead to physical and mental impairments. However, the severity of the clinicopathological characteristics that arise when these two aberrations occur in one patient is unknown. Here, the first case in our knowledge of a single patient (a two‑year‑old female) with 5p partial monosomy and 18q partial trisomy is described. In the present study, chromosome microarray analysis was performed, which identified the imbalance of chromosomes 5 and 18 in the patient. The chromosome aberrations were further confirmed by fluorescence in situ hybridization. By comparing the phenotypes of combined case with those of the individual syndromes, severe clinical phenotypes of the 5p (5p15.33‑p13.3) deletion were confirmed, however, the net effect of the duplication of 18q22.3‑q23 was not determined, as this duplication only appeared to have a weak effect on the patient's phenotypes. The correlation between these chromosomal aberrations and their clinical features has implications for the identification of critical regions of 5p and 18q, particularly for the functional mapping of chromosome 18.

Craniofacial abnormalities among patients with Edwards Syndrome

OBJECTIVE

To determine the frequency and types of craniofacial abnormalities observed in patients with trisomy 18 or Edwards syndrome (ES).

METHODS

This descriptive and retrospective study of a case series included all patients diagnosed with ES in a Clinical Genetics Service of a reference hospital in Southern Brazil from 1975 to 2008. The results of the karyotypic analysis, along with clinical data, were collected from medical records.

RESULTS:

The sample consisted of 50 patients, of which 66% were female. The median age at first evaluation was 14 days. Regarding the karyotypes, full trisomy of chromosome 18 was the main alteration (90%). Mosaicism was observed in 10%. The main craniofacial abnormalities were: microretrognathia (76%), abnormalities of the ear helix/dysplastic ears (70%), prominent occiput (52%), posteriorly rotated (46%) and low set ears (44%), and short palpebral fissures/blepharophimosis (46%). Other uncommon - but relevant - abnormalities included: microtia (18%), orofacial clefts (12%), preauricular tags (10%), facial palsy (4%), encephalocele (4%), absence of external auditory canal (2%) and asymmetric face (2%). One patient had an initial suspicion of oculo-auriculo-vertebral spectrum (OAVS) or Goldenhar syndrome.

CONCLUSIONS:

Despite the literature description of a characteristic clinical presentation for ES, craniofacial alterations may be variable among these patients. The OAVS findings in this sample are noteworthy. The association of ES with OAVS has been reported once in the literature.

Evolving medical and surgical management of infants with trisomy 18

PURPOSE OF REVIEW

To review the evolving management of infants/children with trisomy 18, the prognosis with and without medical intervention, the factors that have contributed to the evolving management strategies, and an approach to the formulation of healthcare management plans for newborns with trisomy 18.

RECENT FINDINGS

There has been a trend from nonintervention for infants/children with trisomy 18 toward management to prolong life. It has become clear that the prognosis for infants/children with trisomy 18 is not as 'hopeless' as was once asserted. However, case series of patients with trisomy 18 managed with a goal of prolonging life are not adequate to evaluate the efficacy of these interventions. They are also not adequate to support the contention that they have no efficacy. In fact, anecdotal evidence and medical plausibility suggest that treatment can prolong life in some cases. This trend has been supported by a change in emphasis from a largely physician-directed model of medical decision-making to a collaborative model, which respects parents' rights to make healthcare decisions for their children and recognizes that judgments about outcomes are often subjective, and social networks, which support and advocate for children with trisomy 18 and their families. An approach to collaborative medical decision-making that is goal-directed is recommended.

SUMMARY

Healthcare management approaches or policies that reject out of hand the goal of prolonging the life of any infant/child with trisomy 18 are not defensible. Management plans should be goal-directed, based on the physician-parent evaluation of the benefits and burdens of care options for the individual child.

Trisomies 18 and 13: trends in prevalence and prenatal diagnosis - population based study

OBJECTIVE

The objective of this study was to determine trends in prenatal detection and current estimates of prevalence for trisomies 18 (T18) and 13 (T13) and their implications for screening policy.

METHODS

We conducted a cohort study from a population-based regional anomaly register covering 995 003 births (1995-2009).

RESULTS

There were 786 affected cases. Total prevalence of T18 increased from 3.95 in 1995-1999 to 6.94 per 10 000 births in 2005-2009 (annual trend χ(2)  = 25.99, p < 0.001) and live birth prevalence, when adjusted for in utero attrition, increased from 1.47 to 2.30 per 10 000 births over the same time (annual trend χ(2)  = 6.36, p = 0.01). For T18 and T13 combined, the proportion of cases diagnosed by prenatal karyotype or suspected by ultrasound increased from 85.1% (165/194) in 1995-1999 to 95.2% (299/314) in 2005-2009 (p < 0.001). In 2005-2009, 50.3% of prenatal cytogenetic diagnoses for T18 and 38.5% of T13 were made after the discovery of first trimester ultrasound anomalies, and the majority, 56.4% (185/328), of affected pregnancies were karyotyped or had ended before 18 weeks.

CONCLUSION

T18 is increasing in prevalence because of maternal age and earlier surveillance. Prenatal diagnosis occurs mostly in the first trimester, without the intrinsic structures of a formal screening programme. These findings support the extension of first trimester combined screening to include T18 and T13.

Trissomia 18: revisão dos aspectos clínicos, etiológicos, prognósticos e éticos

OBJETIVO: Revisar as características clínicas, etiológicas, diagnósticas e prognósticas da trissomia do cromossomo 18 (síndrome de Edwards). FONTES DE DADOS: Foram pesquisados artigos científicos presentes nos portais MedLine, Lilacs e SciELO, utilizando-se os descritores 'trisomy 18' e 'Edwards syndrome'. A pesquisa não se limitou a um período determinado e englobou artigos presentes nestes bancos de dados. SÍNTESE DOS DADOS: A síndrome de Edwards é uma doença caracterizada por um quadro clínico amplo e prognóstico bastante reservado. Há descrição na literatura de mais de 130 anomalias diferentes, as quais podem envolver praticamente todos os órgãos e sistemas. Seus achados são resultantes da presença de três cópias do cromossomo 18. A principal constituição cromossômica observada entre estes pacientes é a trissomia livre do cromossomo 18, que se associa ao fenômeno de não disjunção, especialmente na gametogênese materna. A maioria dos fetos com síndrome de Edwards acaba indo a óbito durante a vida embrionária e fetal. A mediana de sobrevida entre nascidos vivos tem usualmente variado entre 2,5 e 14,5 dias. CONCLUSÕES: O conhecimento do quadro clínico e do prognóstico dos pacientes com a síndrome de Edwards tem grande importância no que diz respeito aos cuidados neonatais e à decisão de instituir ou não tratamentos invasivos. A rapidez na confirmação do diagnóstico é importante para a tomada de decisões referentes às condutas médicas. Muitas vezes, as intervenções são realizadas em condições de emergência, sem muita oportunidade de reflexão ou discussão, e envolvem questões médicas e éticas difíceis.

Perspectives on the care and management of infants with trisomy 18 and trisomy 13: striving for balance

PURPOSE OF REVIEW

At the time of diagnosis of the trisomy 18 and trisomy 13, parents and care providers face difficult and challenging decisions regarding management. Because of the increased infant mortality and developmental outcome associated with both conditions, the conventional approach to management has been to withhold technological support. In recent years, an active dialogue on this topic has emerged. The purpose of this review is to summarize the literature on the outcome of infants with trisomy 18 and 13 and to discuss the key themes in this emerging dialogue.

RECENT FINDINGS

In recent years, several important studies have appeared that have analyzed the issues relevant to this topic, including parental autonomy, best interest of the child standard, and quality of life. Some authorities state that in areas of ambiguity it is best to defer to parents' views, whereas others indicate concern that the best interest standard has given way to parental autonomy. Information on the actual experience of parents of children with trisomy 18 and 13 has been limited until recently.

SUMMARY

The author recommends a balanced approach to counseling families of the newborn with trisomy 18 and 13 at the time of diagnosis. The counseling process should include presentation of accurate survival figures, avoidance of language that assumes outcome, communication of developmental outcome that does not presuppose perception of quality of life, and respect for the family's choice, whether it be comfort care or intervention.

The trisomy 18 syndrome

The trisomy 18 syndrome, also known as Edwards syndrome, is a common chromosomal disorder due to the presence of an extra chromosome 18, either full, mosaic trisomy, or partial trisomy 18q. The condition is the second most common autosomal trisomy syndrome after trisomy 21. The live born prevalence is estimated as 1/6,000-1/8,000, but the overall prevalence is higher (1/2500-1/2600) due to the high frequency of fetal loss and pregnancy termination after prenatal diagnosis. The prevalence of trisomy 18 rises with the increasing maternal age. The recurrence risk for a family with a child with full trisomy 18 is about 1%. Currently most cases of trisomy 18 are prenatally diagnosed, based on screening by maternal age, maternal serum marker screening, or detection of sonographic abnormalities (e.g., increased nuchal translucency thickness, growth retardation, choroid plexus cyst, overlapping of fingers, and congenital heart defects ). The recognizable syndrome pattern consists of major and minor anomalies, prenatal and postnatal growth deficiency, an increased risk of neonatal and infant mortality, and marked psychomotor and cognitive disability. Typical minor anomalies include characteristic craniofacial features, clenched fist with overriding fingers, small fingernails, underdeveloped thumbs, and short sternum. The presence of major malformations is common, and the most frequent are heart and kidney anomalies. Feeding problems occur consistently and may require enteral nutrition. Despite the well known infant mortality, approximately 50% of babies with trisomy 18 live longer than 1 week and about 5-10% of children beyond the first year. The major causes of death include central apnea, cardiac failure due to cardiac malformations, respiratory insufficiency due to hypoventilation, aspiration, or upper airway obstruction and, likely, the combination of these and other factors (including decisions regarding aggressive care). Upper airway obstruction is likely more common than previously realized and should be investigated when full care is opted by the family and medical team. The complexity and the severity of the clinical presentation at birth and the high neonatal and infant mortality make the perinatal and neonatal management of babies with trisomy 18 particularly challenging, controversial, and unique among multiple congenital anomaly syndromes. Health supervision should be diligent, especially in the first 12 months of life, and can require multiple pediatric and specialist evaluations.

Major chromosomal anomalies among very low birth weight infants in the Vermont Oxford Network

OBJECTIVE

To examine prevalence, characteristics, interventions, and mortality of very low birth weight (VLBW) infants with trisomy 21 (T21), trisomy 18 (T18), trisomy 13 (T13), or triploidy.

STUDY DESIGN

Infants with birth weight 401-1500 g admitted to centers of the Vermont Oxford Network during 1994-2009 were studied. A majority of the analyses are presented as descriptive data. Median survival times and their 95% CIs were estimated using the Kaplan-Meier approach.

RESULTS

Of 539 509 VLBW infants, 1681 (0.31%) were diagnosed with T21, 1416 (0.26%) with T18, 435 (0.08%) with T13, and 116 (0.02%) with triploidy. Infants with T18 were the most likely to be growth restricted (79.7%). Major surgery was reported for 30.4% of infants with T21, 9.2% with T18, 6.4% with T13, and 4.8% with triploidy. Hospital mortality occurred among 33.1% of infants with T21, 89.0% with T18, 92.4% with T13, and 90.5% with triploidy. Median survival time was 4 days (95% CI, 3-4) among infants with T18 and 3 days (95% CI, 2-4) among both infants with T13 and infants with triploidy.

CONCLUSION

In this cohort of VLBW infants, survival among infants with T18, T13, or triploidy was very poor. This information can be used to counsel families.

Prenatal diagnosis of mobile flap-like tissue on the ventricular septal defect in a newborn with trisomy 18

Trisomy 18 is the second most common autosomal trisomy in liveborn infants. Various congenital malformations, mental retardation, and high rate of infant mortality in the first year of life are characteristic features of trisomy 18. Congenital heart disease occurs in over 90% of these patients and the most common cardiac lesions are ventricular septal defect, patent ductus arteriosus and atrial septal defect. This is a case report of a baby born with trisomy 18 (postnatal diagnosis) in whom there was an unusual echocardiographic appearance of a mobile structure ("flap-like") around the area of a VSD-which was imaged prenatally.

Chemoresistant hepatoblastoma in a patient with mosaic trisomy 18 treated with orthotopic liver transplantation

We present a 9-month-old male with mosaic trisomy 18 with a right hepatic lobe mass. The tumor was completely resected and identified as pure fetal histology hepatoblastoma but contained increased mitotic activity. Adjuvant chemotherapy consisted of cisplatin, vincristine, and 5-fluorouracil. After the first and fourth cycles of chemotherapy, recurrent tumor developed. The patient underwent rescue orthotopic liver transplantation, and is currently alive without evidence of hepatoblastoma 28 months after transplantation. This report demonstrates the use of orthotopic liver transplantation in a child with mosaic trisomy 18 and hepatoblastoma.

Survival of Texas infants born with trisomies 21, 18, and 13

Trisomies 21, 18, and 13 are the three most common trisomies among infants who survive to 20 weeks gestation or more. Overall information about birth prevalence, natural history, and mortality for all three trisomies is well defined, but information about ethnic-specific rates is limited. Only a few studies have examined mortality rates of trisomies 18 and 13 because so few cases are liveborn and most have very short life spans. This study assessed ethnic-specific population-based survival probabilities among infants for each trisomy. All cases of trisomies 21, 18, and 13 born in Texas between 1999 and 2003 were obtained from the Texas Birth Defects Registry and included 2,260 cases of trisomy 21, 398 cases of trisomy 18, and 213 cases of trisomy 13. Date and cause of death were obtained from the Texas vital statistics records and the National Death Index. Overall, birth prevalence rates (per 10,000 adjusted live births) for the three trisomies were 11.74 (95% CI: 11.25-12.25), 1.34 (95% CI: 1.18-1.52), 0.92 (95% CI: 0.79-1.07), respectively, and are consistent with previously reported rates. There were no differences in survival rates by ethnicity and the median survival for each trisomy was consistent with previous reports. The results of this study provide comprehensive population-based information for survival of infants with trisomies 21, 18, and 13.

Changing clinical presentations and survival pattern in trisomy 18

BACKGROUND

The clinical presentations and survival patterns of infants with trisomy 18 have changed with increasing utilization of prenatal ultrasound and amniocentesis, and improvements in neonatal intensive care.

METHODS

We obtained data on duration of survival, male to female ratio, and clinical details for patients with trisomy 18, and calculated the prevalence rate.

RESULTS

We studied 31 consecutive trisomy 18 infants. The estimated prevalence was 1/4, 144. Eleven (35%) were premature infants, and 20 (65%) were full term. Mean birth weight was 1896 g. Median life expectancy was 12 days; 11 days for males and 14 days for females (p = 0.87). The short-term survival rates of 1 week, 4 weeks, and 6 months were 58%, 32%, and 10%, respectively. The long-term survival rates of 1 year, 2 years, and 3 years were 6%, 6%, and 3%, respectively. Families signed do-not-resuscitate consent forms for five male (50%) and 19 female infants (90%) (p = 0.043).

CONCLUSION

All trisomy 18 infants in this study were preterm or full-term deliveries. Mean birth weight was lower than previously reported, and a high percentage of families signed do-not-resuscitate consent forms. Females did not survive longer than males, due to more females not being resuscitated. Most infants died in the first few weeks of life, but 3-6% of infants lived for 21 year. The possibility of long-term survival should be considered when counseling parents regarding trisomy 18.

Attitudes of neonatologists toward delivery room management of confirmed trisomy 18: potential factors influencing a changing dynamic

OBJECTIVE

The objective of this study was to determine the attitude of neonatal providers toward delivery room resuscitation of an infant with confirmed trisomy 18 with known congenital heart disease at >/=36 weeks of gestation.

METHODS

A multiple-choice questionnaire listing this clinical scenario was completed by neonatologists and fellows staffing level III NICUs. Potential factors influencing the decision to initiate resuscitation included maternal preference, neonatal condition at birth, obstetric care, and legal concerns.

RESULTS

Fifty-four (76%) of 71 surveys were completed. Of respondents, 44% indicated that they would be willing to initiate resuscitation. Maternal preference (70%) was the primary reason to initiate resuscitation, with the appearance of the neonate in the delivery room (46%) and legal concerns (25%) as additional factors.

CONCLUSIONS

Until recently, there was universal consensus that trisomy 18 was a lethal anomaly for which resuscitation in the delivery room was not indicated. These data indicate that more providers (44%) than anticipated would consider initiation of resuscitation for an infant with trisomy 18 even with congenital heart disease. We speculate that support for the best-interest standard for neonates is diminishing in favor of ceding without question to parental autonomy. This shift may have profound implications for ethical decisions in the NICU.

Is trisomy 18 increasing in Sweden? An analysis of the syndrome during a ten year period and a comparison with a French registry

This paper reports an analysis of trisomy 18 in Sweden between 1978 and 1987 and a comparison with data from the Rhône-Alpes/Auvergne registry in France. A strong maternal age dependency is seen, which parallels that observed for Down syndrome. The patterns of registered malformations in the two data sets are quite similar. A progressive increase of the prevalence at birth of trisomy 18 is seen in Sweden during the ten years but not in France. This increase seems to result, at least in part, from an increased identification of the trisomy among malformed infants. A parallel decrease in the reporting of infants with the "cardinal" trisomy 18 malformations is indicated.

Quality control of prenatal sonography in detecting trisomy 18. The value of perinatal autopsy

AIMS

This study was designed to compare the prenatal ultrasound findings and postmortem pathologic findings of fetuses with trisomy 18.

STUDY DESIGN

Of 22,150 fetal chromosome analyses, 70 fetuses with trisomy 18 were diagnosed between 1990 and 2004. Sonographic and perinatal autopsy findings were compared by organ system and their correlation was assigned to 1 of 3 categories.

RESULTS

There were 164 separate major structural abnormalities found on autopsy. Of them, sonography detected 72 (43.9%). Among major defects the agreement was more than 75% of all abnormalities of these systems: central nervous system (80%), abdominal abnormalities (87.5%) and cystic hygroma (100%). Whereas, the sensitivity of sonography was lower in these organ systems: cardiac system (66.6%), facial abnormalities (26.3%), urinary system (27.3%) and extremities (8.7%). The rate of additional findings at autopsy was 56.1% and involved mainly 2 organ systems: face (including ear) and extremities (including hands and feet). Some ultrasound findings (n=15) were not confirmed at autopsy in our series.

CONCLUSIONS

This study confirms that perinatal autopsy provides additional information in many fetuses with trisomy 18. Besides obstetricians, pediatricians and geneticists, specialized perinatal pathologists have an important role in the multidisciplinary management of prenatally diagnosed fetal malformations. In addition, examining the correlation between sonography and pathologic findings may indicate potential markers for sonographic screening of trisomy 18.

Trisomy 18: Fetal ultrasound findings at different gestational ages

The aim of this article is evaluate the sonograhic findings in fetuses with trisomy 18 at different gestational ages. The cases were recruited from pregnant women, who underwent to prenatal diagnosis in the period from October 1995 to September 2006. Seventy-one fetuses with trisomy 18 were diagnosed. On review of the sonograms the majority of these cases had ultrasound anomalies (sensitivity of 91.5%). The most frequent anomalies were abnormalities of extremities (40.8%) and fetal growth restriction (35.2%). More frequently (54.9%) two or more anomalies were present. Nearly all fetuses with trisomy 18 had sonographic abnormalities. Likely improved high-resolution equipment and attention to details by skilled operators led to the detection of most anomalies to trisomy 18. Knowledge of types of specific ultrasound findings can improve prenatal diagnosis in order to provide invasive procedures only when indicated, and to avoid amniocentesis when ultrasound signs are not observed in women at high risk from positive biochemical testing.

Role of second trimester sonography in detecting trisomy 18: a review of 70 cases

PURPOSE

To investigate the role of second-trimester sonographic examination in the prenatal diagnosis of trisomy 18.

METHODS

Out of 22,150 fetal chromosomal analyses performed between 1990 and 2004, 70 trisomy 18 fetuses were found. The sonographic findings of this aneuploidy were analyzed.

RESULTS

The average maternal age was 32.4 years; the average gestational age was 19.5 weeks. Major anomalies were seen in 61 (87.1%) of the 70 fetuses with trisomy 18; among these, cardiac anomalies were the most common (47.1%), with a 27.1% incidence of ventricular septal defects. Anomalies of the central nervous system were seen in 35.7% of cases; abnormal head shape was the most frequently detected anomaly in this group (12.9%). Fifty-six (80%) of the fetuses had at least 1 minor anomaly; of these, choroid plexus cyst was the most common (38.6%). Increased nuchal fold thickness was detected in 17.1% of cases.

CONCLUSION

The vast majority of trisomy 18 fetuses have sonographically detectable abnormalities in the second trimester. Both the 87.1% frequency of major anomalies and the 80% frequency of minor anomalies are substantially higher than multiple biochemical marker tests could achieve. It was also demonstrated that fetal echocardiography plays a pivotal role in the diagnosis of trisomy 18.

Pregnancy outcome of fetuses with trisomy 18 identified by prenatal sonography and chromosomal analysis in a perinatal center

To investigate the pregnancy outcome of fetuses affected with trisomy 18, we analyzed 63 cases diagnosed at our hospital from January 1993 to December 2004. Twenty-nine were males and 34 were females. Fifty-eight were prenatally diagnosed, and in 16 (27.6%) of them intrauterine fetal death (IUFD) occurred between 28 weeks and 41 weeks gestation (34.6 +/- 3.9 weeks, Mean +/- SD). Ten (17.2%) fetuses died during labor and their age ranged from 30 weeks to 40 weeks of gestation. The total number of cases ending in fetal demise was 26 (44.8%) and the mean gestational age at the time of fetal demise was 35.0 +/- 3.6 weeks (Mean +/- SD). All liveborn infants (n = 36) were born after 31 weeks gestation. In our study the preterm birth ratio for trisomy 18 is 34.8%, which is much higher than the ratio for the general population. Females are more likely than males to be long-term survivors. These data are helpful in the counseling of parents faced with the difficult decision of whether or not to continue a pregnancy with a fetus affected with trisomy 18.

Trisomy 18 in neonates: prenatal diagnosis, clinical features, therapeutic dilemmas and outcome

The study aimed to analyse the clinical courses of aggressively treated neonates with cytogenetically confirmed trisomy 18, with special attention focused on the efficiency of prenatal diagnostics, associated malformations, therapeutic dilemmas and outcomes. We investigated retrospectively the data concerning 20 neonates with trisomy 18, admitted to the Neonatal Intensive Care Unit (NICU) in Katowice between January 2000 and February 2005. Their birth weights ranged from 650 g to 2400 g, mean 1812 g; gestational age ranged from 27 to 42 weeks, median 38 weeks. Intrauterine growth retardation was noticed in 90% of neonates. Trisomy 18 was suspected prenatally in 40% of cases. Most (80%) of newborns were delivered by caesarean section (92% of neonates with prenatally unrecognized chromosomal defects, 62% of neonates with trisomy 18 suspicion) and 70% of infants needed respiratory support immediately after birth. Cardiac defects were present in 95%, central nervous system malformations in 65%, severe anomalies of digestive system or abdominal wall in 25% of patients. Nine surgical operations were performed during hospitalization (4 were palliative cardiac surgeries). Six patients (30%) survived the neonatal period and were discharged from the NICU. The median survival of the neonates who died was 20 days. In 4 cases cardiac problems implicated their death; in others, deaths were attributed to multiorgan failure, prematurity and/or infection. Further improvement of efficiency of prenatal ultrasound screening for diagnosis of trisomy 18 in the fetus is necessary. A lack of prenatal diagnosis of trisomy 18 in the fetus results in a high rate of unnecessary caesarean sections in these pregnancies. Despite the aggressive treatment most neonates with trisomy 18 died during the neonatal period. The majority of deaths were attributed to cardiorespiratory and multiorgan failure. Concerning the poor prognosis, prompt karyotyping (using FISH) of clinically suspected trisomy 18 is very important, because many invasive procedures and surgeries may then be avoided.

Survival with trisomy 18--data from Switzerland

We collected records of 352 cases of trisomy 18 karyotyped between 1964 and May 2003 from the two major cytogenetic laboratories in Northeastern Switzerland. For more detailed information about the cases we contacted the referring physicians and/or the families of the patients. In this way we collected data about survival and malformations of 161 live births, 136 induced abortions and 29 stillborns or spontaneous abortions. In 26 cases of trisomy 18, only incomplete records were available. We observed that each year more cases of trisomy 18 were cytogenetically diagnosed in the two laboratories. Before 1984 almost no prenatal diagnoses were made; however, after this date the number of prenatal diagnoses increased and in the last 10 years, accounted for 75% of all cases. A decrease in the number of postnatally diagnosed cases was also observed over the same period of time. One third of the live-born children with trisomy 18 died during the first day of life. After 1 week, 1 month and 1 year of life the survival rates were 40, 22 and 6%, respectively. The median survival was 4 days, and only 1% of the children survived until their 10th birthday. Females were more likely to survive long term. In 63 cases autopsy reports were available for review. In 97% of these cases three or more malformations were found: 67% had VSD, 32% had horseshoe kidneys, 21% had esophageal atresia, 14% had omphalocele, 14% had facial clefts, and 11% had diaphragmatic hernias. In more than 50% genital hypoplasia was also described. We further analyzed survival of live-borns in relation to the length of gestation and to VSD and esophageal atresia.

Trisomy of chromosome 18 in the baboon (Papio hamadryas anubis)

Trisomy 18 is usually a lethal chromosomal abnormality and is the second most common autosomal trisomy in humans, with an incidence of 1:8000 live births. It is commonly associated with abnormalities of the lower and upper extremities, having the frequency of 95% and 65%, respectively. A newborn female olive baboon (Papio hamadryas anubis) was diagnosed with intrauterine growth retardation and severe arthrogryposis-like congenital joint deformities. Cytogenetic analysis including G-banding and fluorescence in situ hybridization (FISH) revealed that the congenital abnormalities were associated with chromosomal mosaicism for trisomy 18. Genetic analysis with microsatellites from chromosome 18 confirmed the maternal origin of the extra chromosome 18. This is the first report of trisomy 18 in the baboon, which may be a promising animal model of human disease.

Congenital malformations among liveborn infants with trisomies 18 and 13

Trisomy 18 and trisomy 13 are associated with serious and/or fatal birth defects, with death frequently occurring in the first month of life. Previous studies are limited by small samples and are dated. This study characterized the comorbid birth defects associated with trisomy 18 and trisomy 13 among US liveborn infants using the Healthcare Cost and Utilization Project's Kids' Inpatient Database and Nationwide Inpatient Sample, two large, current and nationally representative databases. The occurrence of 39 commonly reported comorbid birth defects among infants with trisomies 18 and 13 was compared to the occurrence of malformations among newborns without trisomies. The prevalences of trisomy 18 and 13 were 1.29/10,000 and 0.85/10,000 live births, respectively. Among infants with trisomy 18, 61% were female, 45.4% with heart defects. Among those with trisomy 13, 53% were female, 38.4% had heart defects, 24.5% had orofacial anomalies, and 11.2% had central nervous system abnormalities. More than half of the newborns with both conditions died prior to discharge. This updated information can be used to inform clinical decision-making and may help providers better prepare families for infants with trisomies.

Neonatal management of trisomy 18: Clinical details of 24 patients receiving intensive treatment

Management of neonates with trisomy 18 is controversial, supposedly due to the prognosis and the lack of precise clinical information concerning efficacy of treatment. To delineate the natural history of trisomy 18 managed under intensive treatment, we reviewed detailed clinical data of 24 patients with full trisomy 18 admitted to the neonatal intensive care unit of Nagano Children's Hospital, providing intensive treatment to those with trisomy 18, from 1994 to 2003. Cesarean, resuscitation by intubation, and surgical operations were performed on 16 (67%), 15 (63%), and 10 (42%) of the patients, respectively. Mechanical ventilation was required by 21 (88%), and 6 (29%) of them were extubated. Survival rate at age 1 week, 1 month, and 1 year was 88%, 83%, and 25%, respectively. Median survival time was 152.5 days. Respiration was not stabilized in two patients with left diaphragmatic eventration and hypoplasia accompanied by lung hypoplasia, even with maximal ventilation. The common underlying factors associated with death were congenital heart defects and heart failure (96%), followed by pulmonary hypertension (78%). The common final modes of death were sudden cardiac or cardiopulmonary arrest (26%) and possible progressive pulmonary hypertension-related events (26%). These data of improved survival, through neonatal intensive treatment, are helpful for clinicians to offer the best information on treatment options to families of patients with trisomy 18.

Clinical characteristics and survival of trisomy 18 in a medical center in Taipei, 1988–2004

Trisomy 18 is the second most common autosomal trisomy in newborns. The birth prevalence of this disorder is approximately 1 in 3,000 to 1 in 8,000, and the life span of the majority of patients is less than 1 year. As information regarding outcome in trisomy 18 is rather fragmentary in the literature, this study is aimed at investigating the survival and natural history of trisomy 18. We also evaluated the survival age and management of trisomy 18 in two different periods, before and after the implementation of National Health Insurance (NHI) program. Thirty-nine cases of trisomy 18 were collected in Mackay Memorial Hospital in a 17-year period, from 1988 to 2004. Delivery data, survival age, management before and after the implementation of NHI program, structural defects, image findings and cytogenetic results were analyzed by medical and nurse's records. The diagnosis of trisomy 18 was based on the prenatal amniocentesis or postnatal chromosome analysis. Three patients had trisomy 18 mosaicism. Since cardiovascular and central nervous systems are the most common organ systems involved in this disorder, 31 patients received brain ultrasonography and heart ultrasonography for evaluation of their multiple anomalies after admission. All patients except one died in their first year due to severe malformations of the cardiovascular or central nervous systems. The median survival age was 6 days. We found a longer survival with female patients than with male patients (P < 0.05). Implementation of NHI program in the more recent decade of this study period was associated with longer survival of trisomy 18 (P < 0.05). The three most common structural defects were clenched hands (95%), rocker bottom feet (90%), and low set or malformed ears (90%). Low birth weight was present in 90%. By cardiac ultrasonography, the top four heart defects were ventricular septal defect (94%), patent ductus arteriosus (77%) and atrial septal defect (68%). However, ten cases (32%) had complex congenital heart defects. By brain ultrasonography, the most common brain lesion was cerebellar hypoplasia (32%), followed by brain edema (29%), enlarged cisterna magna (26%) and choroid plexus cysts (19%). Although most patients with trisomy 18 die within the first few weeks after birth, it is important to recognize that a small but notable percentage of these patients will survive the first year. When prenatal or postnatal decisions need to be made, the possibility of long-term survival should be included in any discussion to enable families to make the most appropriate decision.

Diploid-aneuploid mosaicism in human embryos cultured to the blastocyst stage

OBJECTIVE

To examine diploid-aneuploid mosaicism in human in vitro cultured blastocysts.

DESIGN

A laboratory study on spare blastocysts from an IVF program.

SETTING

University hospital laboratory.

PATIENTS(S)

Forty-three couples undergoing IVF or intracytoplasmic sperm injection.

INTERVENTION(S)

Ninety-one blastocysts were spread for fluorescence in situ hybridization using the HCl-Tween 20 method. A total of 6,664 nuclei were analyzed for aneuploidy using fluorescent DNA probes specific to chromosomes 2, 7, and 18.

MAIN OUTCOME MEASURE(S)

The proportion of aneuploid cells within each blastocyst.

RESULTS(S)

The incidence of diploid-aneuploid mosaicism among 91 blastocysts examined was 17.6%. All of the mosaic blastocysts were abnormal for only one of the three chromosomes tested, with the incidence of involvement of chromosomes 2, 7, and 18 being 3.3%, 8.8%, and 5.5%, respectively. The majority of the mosaic blastocysts had low proportions of aneuploid cells. Ten of the 16 (62.5%) affected blastocysts were of morphology compatible with implantation.

CONCLUSION(S)

A considerable proportion of human IVF blastocysts show a form of mosaicism that has been observed in fetal and placental tissues. This mosaicism often arises at the final stage of preimplantation development in vitro and is present in blastocysts of morphology compatible with implantation.

Mortality throughout early childhood for Michigan children born with congenital anomalies, 1992-1998

BACKGROUND

Congenital anomalies are a leading cause of infant deaths, accounting for almost a fifth of all infant deaths. Few studies have researched the survival experience of infants born with congenital anomalies past the infant stage.

METHODS

Using birth and death files routinely linked to the Michigan Birth Defects Registry, we identified all singleton infants during calendar years 1992 through 1998 with reportable congenital anomalies for our study. A comparative file of children born without congenital anomalies during the same time period was developed using linked birth and death files. The mortality data were assessed by age at death (through age six) and race to determine mortality rates, relative risks, hazard ratios, and survival trends.

RESULTS

Throughout early childhood, children born with congenital anomalies had a high risk of mortality compared with all other children. The overall 7-year hazard ratio comparing children with congenital anomalies with all other children was 7.2. Overall mortality rates for black children were significantly higher than white children through the age of seven, irrespective of whether they had congenital anomalies. Among children with congenital anomalies, this disparity disappeared after adjusting for birth weight, sex, mother's age, mother's education, and number of organ systems affected.

CONCLUSIONS

Compared with children without congenital anomalies, children born with congenital anomalies had a higher risk of mortality well beyond the infant period. Racial disparities in mortality rates among children with congenital anomalies were due to confounding factors.

Population-based analyses of mortality in trisomy 13 and trisomy 18

OBJECTIVE

Although trisomy 13 and trisomy 18 are generally considered to be lethal, long-term survival of patients has been reported. We sought to evaluate mortality in people with trisomy 13 or 18 using 2 population-based strategies.

METHODS

In the first analysis, infants who had trisomy 13 or 18 and were born during 1968-1999 were identified using the Metropolitan Atlanta Congenital Defects Program, a population-based birth defects surveillance system. Dates of death were documented using hospital records, Georgia vital records, and the National Death Index. In the second analysis, we used the Multiple-Cause Mortality Files compiled from US death certificates from 1979 through 1997. Using these 2 analyses, we examined median survival time or median age at death, survival beyond 1 year of age, and factors associated with longer survival.

RESULTS

Using Metropolitan Atlanta Congenital Defects Program, we identified 70 liveborn infants with trisomy 13 and 114 liveborn infants with trisomy 18. Median survival time was 7 days (95% confidence interval [CI]: 3-15) for people with trisomy 13 and 14.5 days (95% CI: 8-28) for people with trisomy 18. For each condition, 91% of infants died within the first year. Neither race nor gender affected survival for trisomy 13, but for trisomy 18, girls and infants of races other than white seemed to survive longer. The presence of a heart defect did not seem to affect survival for either condition. Using MCMF, we identified 5515 people with trisomy 13 and 8750 people with trisomy 18 listed on their death certificates. Median ages at death for people with trisomy 13 and trisomy 18 both were 10 days; 5.6% of people with trisomy 13 and 5.6% of people with trisomy 18 died at age 1 year or greater. Race and gender seemed to affect survival in both conditions, with girls and blacks showing higher median ages at death.

CONCLUSIONS

Although survival is greatly affected by trisomy 13 and trisomy 18, 5% to 10% of people with these conditions survive beyond the first year of life. These population-based data are useful to clinicians who care for patients with these trisomies or counsel families with infants or fetuses who have a diagnosis of trisomy 13 or 18.