Population-based study of tracheoesophageal fistula and esophageal atresia

Prevalence of esophageal atresia among 18 international birth defects surveillance programs

BACKGROUND

The prevalence of esophageal atresia (EA) has been shown to vary across different geographical settings. Investigation of geographical differences may provide an insight into the underlying etiology of EA.

METHODS

The study population comprised infants diagnosed with EA during 1998 to 2007 from 18 of the 46 birth defects surveillance programs, members of the International Clearinghouse for Birth Defects Surveillance and Research. Total prevalence per 10,000 births for EA was defined as the total number of cases in live births, stillbirths, and elective termination of pregnancy for fetal anomaly (ETOPFA) divided by the total number of all births in the population.

RESULTS

Among the participating programs, a total of 2943 cases of EA were diagnosed with an average prevalence of 2.44 (95% confidence interval [CI], 2.35-2.53) per 10,000 births, ranging between 1.77 and 3.68 per 10,000 births. Of all infants diagnosed with EA, 2761 (93.8%) were live births, 82 (2.8%) stillbirths, 89 (3.0%) ETOPFA, and 11 (0.4%) had unknown outcomes. The majority of cases (2020, 68.6%), had a reported EA with fistula, 749 (25.5%) were without fistula, and 174 (5.9%) were registered with an unspecified code.

CONCLUSIONS

On average, EA affected 1 in 4099 births (95% CI, 1 in 3954-4251 births) with prevalence varying across different geographical settings, but relatively consistent over time and comparable between surveillance programs. Findings suggest that differences in the prevalence observed among programs are likely to be attributable to variability in population ethnic compositions or issues in reporting or registration procedures of EA, rather than a real risk occurrence difference. Birth Defects Research (Part A), 2012.

Eosinophilic esophagitis after esophageal atresia: is there an association? Case presentation and literature review

Eosinophilic esophagitis (EoE) is a relatively new condition resulting in dysphagia or symptoms resembling gastroesophageal reflux disease, symptoms that also are common in patients with a history of esophageal atresia. We present 2 patients with persistent dysphagia after repair of esophageal atresia that was caused by EoE. Although the exact etiology and pathogenesis of EoE remain unclear, it is now generally accepted that it is the result of a T-helper cell 2-type immune response with a crucial role for the eosinophil-specific chemotaxis factor eotaxin 3 and eosinophils. Because there are genetic similarities between esophageal atresia and EoE, we speculate that patients with esophageal atresia are at increased risk for developing EoE.

Aspects of esophageal atresia in a population-based setting: incidence, mortality, and cancer risk

PURPOSE

To estimate the incidence, mortality and cancer risk of the congenital malformation esophageal atresia (EA) in a population-based investigation.

METHODS

A population-based cohort study of EA patients registered in three nationwide registers in Sweden in 1964-2007. The incidence of EA per total number of live births was assessed. Mortality and cancer occurrence were expressed as standardized mortality ratio (SMR) and standardized incidence ratio (SIR) with 95% confidence intervals (CI). Mortality was further analyzed by Cox regression and expressed as hazard ratio with 95% CI.

RESULTS

The EA cohort comprised 1,126 patients. The mean incidence was 3.16 per 10,000 live births, without any temporal changes (p for trend =0.94). Associated anomalies were present in 42% and chromosomal abnormalities in 5%. EA patients had an almost 12 times higher risk of mortality compared to the background population (SMR 11.8, 95% CI 10.3-13.5). The mortality increase was most pronounced during the first 5 years after birth. Survival improved during the study period (p for trend =0.0001). EA did not entail a strongly increased cancer risk (SIR 0.9; 95% CI 0.2-2.6).

CONCLUSIONS

EA has a stable incidence, the survival has improved substantially during recent decades, and the cancer risk might not be increased.

Nine new twin pairs with esophageal atresia: a review of the literature and performance of a twin study of the disorder

BACKGROUND

Isolated esophageal atresia (EA) is a rare congenital malformation whose etiology remains largely unknown. Nine twin pairs with EA were identified from our clinical service, prompting the performance of a systematic review of the literature and the first reported twin study of isolated EA.

METHODS

A total of 330 twin pairs with EA were identified from the literature. The zygosity, concordance, and malformation (isolated vs. nonisolated) status of all 339 twin pairs were evaluated. A total of 72 twin pairs (4 of 9 / 68 of 330) fulfilled the criteria for inclusion in a classic twin study of isolated EA.

RESULTS

The pairwise concordance rates were 50% (95% confidence interval [CI], 34-66%) for monozygous (MZ) twin pairs and 26% (95% CI, 15-42%) for dizygous (DZ) twin pairs (p = 0.033). The probandwise concordance rates were 67% (95% CI, 53-78%) for MZ twin pairs and 42% (95% CI, 29-56%) for DZ twin pairs (p = 0.011). The MZ/DZ ratios were 1.9 for pairwise analysis and 1.6 for probandwise analysis. The familial risk ratios for MZ and DZ twin pairs were 1700 and 900, respectively.

CONCLUSION

The observation of higher concordance rates for MZ compared to DZ twin pairs indicates that genetic factors contribute to isolated EA.

Biochemical amniotic fluid pattern for prenatal diagnosis of esophageal atresia

Prenatal diagnosis of esophageal atresia (EA) may improve the outcome of affected neonates by allowing optimization of both prenatal and postnatal care. Prenatal sonographic detection is based on polyhydramnios and/or nonvisualization of the fetal stomach bubble, two signs with a large number of etiologies. We evaluated a biochemical approach to improving diagnostic efficiency. We compared amniotic fluid biochemical markers in 44 EA cases with 88 polyhydramnios and 88 nonpolyhydramnios controls. Both matched for GA with cases. Total proteins, alpha-fetoprotein (AFP), and digestive enzyme activities were assayed, including gamma-glutamyl transpeptidase (GGTP). We defined an EA index (AFP multiplied by GGTP). A significant difference (p < 0.0001) was observed for total protein, AFP, GGTP, and EA index between the EA group and each of the two control groups. No statistical difference was observed for any marker between the two most frequent EA subgroups (type I and type III) or between the two control groups. Using a cutoff of 3 for the EA index, 98% sensitivity and 100% specificity were observed for amniotic fluid prenatal diagnosis of EA, whatever the anatomical type. A large prospective series is required to confirm these results.

De novo deletion of chromosome 20q13.33 in a patient with tracheo-esophageal fistula, cardiac defects and genitourinary anomalies implicates GTPBP5 as a candidate gene

BACKGROUND

CASE REPORT

CONCLUSIONS

Etiology of esophageal atresia and tracheoesophageal fistula: "mind the gap"

Esophageal atresia and tracheoesophageal fistula (EA/TEF) are major congenital malformations affecting 1:3500 live births. Current research efforts are focused on understanding the etiology of these defects. We describe well-known animal models, human syndromes, and associations involving EA/TEF, indicating its etiologically heterogeneous nature. Recent advances in genotyping technology and in knowledge of human genetic variation will improve clinical counseling on etiologic factors. This review provides a clinical summary of environmental and genetic factors involved in EA/TEF.

Chronic hypertension with related drug treatment of pregnant women and congenital abnormalities in their offspring: a population-based study

Chronic hypertension (CH) is a common chronic disease and occurs frequently in pregnant women. The teratogenic/fetotoxic effect of certain antihypertensive drugs has been shown. The objective of this study was to investigate the association between pregnant women with CH and the possible risk of congenital abnormalities (CAs) among their offspring. The prevalence of medically recorded CH in the prenatal maternity logbook was compared between 1030 pregnant women who later had offspring with CA (case group) and 1579 pregnant women with CH who later delivered newborn infants without CA (control group). Control newborn infants were matched to cases in the population-based data set of the Hungarian Case-Control Surveillance System of Congenital Abnormalities during 1980-1996. Of 23 different CA groups with informative offspring, esophageal atresia/stenosis was a greater risk in pregnant women with CH (adjusted odds ratios with 95% confidence intervals: 3.1, 1.4-6.8). In conclusion, a higher risk of esophageal atresia/stenosis was found in the offspring of pregnant women with severe CH, which could not be explained by related drug treatments. This finding requires confirmation or lack thereof by future studies.

Oesophageal atresia and tracheo-oesophageal fistula: current management strategies and complications

The successful operative management of oesophageal atresia and tracheo-oesophageal atresia has been available for approximately 70 years. During this time neonatal intensive care has evolved, surgical techniques have improved and consequently near 100% survival for this condition may now be achieved. In keeping with promising results, the co-morbidities of the condition have gained increasing recognition. In this article, the clinical course from antenatal assessments, neonatal surgery and co-morbidities from infancy to adulthood are reviewed to provide a broad overview of the condition.

Genetic and environmental factors in the etiology of esophageal atresia and/or tracheoesophageal fistula: an overview of the current concepts

Esophageal atresia and/or tracheoesophageal fistula (EA/TEF) are severe congenital anomalies. Although recent years have brought significant improvement in clinical treatment, our understanding of the etiology of these defects is lagging. Many genes and genetic pathways have been implicated in the development of EA/TEF, but only a few genes have been shown to be involved in humans, in animals, or in both. Extrapolating data from animal models to humans is not always straightforward. Environmental factors may also carry a risk, but the mechanisms are yet to be elucidated. This review gives an overview of the current state of knowledge about both genetic and environmental risk factors in the etiology of EA/TEF.

Surgical outcomes of esophageal atresia without fistula for 24 years at a single institution

PURPOSE

The aim of the study was to evaluate the surgical outcome of esophageal atresia (EA) without fistula for 24 years at a single tertiary center for pediatric surgery.

METHODS

The study used a retrospective chart review of infants diagnosed with EA without fistula between 1981 and 2005.

RESULTS

Of 33 patients with EA without fistula, 31 charts were available. Mean birth weight was 2327 g (range, 905-3390 g), and 71% were male. Most common associated anomalies were cardiac (n = 6; 19%) and renal (n = 5; 16%), followed by vertebral (n = 4; 13%) and anorectal (n = 2; 7%). The median initial esophageal gap was 5 vertebral bodies. Six had a primary repair, and 25 patients had esophageal replacement at a median age of 7 months. This involved gastric transposition in 20 (1 followed failed jejunal interposition), colonic interposition in 5, jejunal interposition in 1 (after a failed colonic), and repair at another center in 1. With a median review of 9 years, 21 patients had long-term sequelae with the need for multiple further surgical procedures including an antireflux procedure in 5. One patient died.

CONCLUSIONS

Management of EA without fistula remains challenging. Most patients required staged treatment that included esophageal replacement. The frequency of late complications indicates the need for programmed long-term review.

Associated malformations in patients with esophageal atresia

Esophageal atresia is a common type of congenital malformation. The etiology of esophageal atresia is unclear and its pathogenesis is controversial. Because previous reports have inconsistently noted the type and frequency of malformations associated with esophageal atresia, we conducted this study in a geographically well-defined population, evaluating the birth prevalence of esophageal atresia and associated malformations ascertained between 1979 and 2003 in 334,262 consecutive births. Of the 99 patients with esophageal atresia, 46 (46.5%) had associated malformations. These included patients with chromosomal abnormalities (8 patients, 8%); non-chromosomal recognized syndromes (4 patients), including one each CHARGE syndrome, Fanconi anemia, Fryns syndrome, and Opitz G/BBB syndrome; associations including VACTERL (10 patients), and one schisis; one oculo-auriculo-vertebral spectrum; one malformation complex, a sirenomelia, and non-syndromic multiple congenital anomalies (MCA) (21 patients, 21%). Malformations of the cardiovascular system (24%), urogenital system (21%), digestive system (21%), musculoskeletal system (14%), and central nervous system (7%) were the most common other congenital malformations occurring in patients with esophageal atresia and non-syndromic MCA. We observed a high prevalence of total malformations and specific patterns of malformations associated with esophageal atresia which emphasizes the need to evaluate all patients with esophageal atresia for possible associated malformations. The malformations associated with esophageal atresia could be classified into a recognizable malformation syndrome or pattern in 25 out of 46 patients (54%).

Maternal periconceptional exposure to cigarette smoking and alcohol and esophageal atresia +/- tracheo-esophageal fistula

BACKGROUND

Esophageal atresia (EA) is a moderately frequent birth defect that often occurs with tracheo-esophageal fistula (TEF). Etiologic studies for EA+/-TEF have produced inconsistent results.

METHODS

This study used data from the National Birth Defects Prevention Study (NBDPS) to examine the association between maternal periconceptional exposure to cigarette smoking and alcohol and EA+/-TEF. Cases of EA+/-TEF and unaffected controls with an estimated date of delivery from October 1997 through December 2003 were identified, and telephone interview reports for smoking and alcohol exposure were obtained from birth mothers of 334 cases and 4,967 controls. Odds ratios (OR)s and 95% confidence intervals (CI)s, adjusted for several covariates, were calculated to assess associations.

RESULTS

ORs were near unity for all EA+/-TEF cases combined and any periconceptional exposure to cigarette smoking (OR = 1.1; CI = 0.8,1.6) or alcohol (OR = 1.2; CI = 0.8,1.8). For cigarette smoking, some elevated ORs were found but varied by type of smoking exposure. No consistent patterns were identified for number of cigarettes smoked per day. For alcohol, ORs were weak to moderately elevated with increasing number of drinks consumed and for binge drinkers compared to non-binge drinkers. ORs were further elevated among mothers who reported active+passive exposure to cigarette smoking and alcohol (OR = 2.5; CI = 1.1,5.6). For both exposures, ORs were higher for cases with additional major defects compared to isolated cases.

CONCLUSIONS

These results, based on one of the largest published samples of EA+/-TEF cases, suggest a role for these exposures in the etiology of EA+/-TEF, although further study is needed to replicate the observed associations.

Influence of maternal parity, age, and ethnicity on risk of esophageal atresia in the infant in a population-based study

BACKGROUND

The etiology of esophageal atresia (EA) is virtually unknown. We hypothesized that the maternal factors low parity, high age, and white ethnicity are involved.

METHODS

A Swedish nationwide, population-based, case-control study was nested in a cohort of newborn children in 1982 to 2004. Among 2,305,858 deliveries, 722 cases of EA and 3610 controls were included. Conditional logistic regression was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs). Matching, stratification, and multivariable regression were used to adjust for potential confounding.

RESULTS

A more than 30% decreased risk of EA was found for mothers delivering their second (OR, 0.68; 95% CI, 0.56-0.83) or third child (OR, 0.64; 95% CI, 0.49-0.83) compared to primiparous mothers. Children of women giving birth when 35 to 40 years and older than 40 years showed a 2-fold (OR, 2.09; 95% CI, 1.09-3.99) and 3-fold (OR, 3.04; 95% CI, 1.37-6.74) increased risk of EA, respectively, compared to those of mothers younger than 20 years. This association remained when chromosomal abnormality cases were excluded (P = .004). There was a 66% increase in risk of isolated EA in children of mothers of white (OR, 1.66; 95% CI, 1.06-2.61), compared to mothers who are not of white ethnicity.

CONCLUSIONS

This study indicates an increased risk of EA in children of mothers having their first delivery, of older age, and of white ethnicity.

Non-VACTERL-type anomalies are frequent in patients with esophageal atresia/tracheo-esophageal fistula and full or partial VACTERL association

BACKGROUND

The VACTERL association is the nonrandom co-occurrence of Vertebral anomalies, Anal atresia, Cardiovascular malformations, Tracheo-esophageal fistula (TEF) and/or Esophageal atresia (EA), Renal anomalies, and/or Limb-anomalies. The full phenotype of patients with EA/TEF and other anomalies of the VACTERL spectrum of defects association is not well described in the literature.

METHODS

Data on patients with EA/TEF seen in two pediatric surgical centers in the Netherlands between January 1988 and August 2006 were evaluated for defects of the VACTERL spectrum as well as non-VACTERL-type defects. The presence of two or more defects of the VACTERL spectrum in addition to EA/TEF was the criterion for inclusion in this study. A detailed description was made of all defects.

RESULTS

Of 463 patients with EA and/or TEF, 107 (23.1%) fulfilled the inclusion criterion, of which seventeen cases had a recognized etiology and were excluded, leaving 90 cases (19.4%) for analysis. Other than the esophagus and the trachea, the vertebrae/ribs and the cardiovascular system were most commonly affected (68.9 and 65.6%, respectively). Interestingly, 70% of cases had additional non-VACTERL-type defects, with high occurrences for single umbilical artery (20%), genital defects (23.3%), and respiratory tract anomalies (13.3%).

CONCLUSIONS

Many patients with EA/TEF and at least two other defects of the VACTERL spectrum also display non-VACTERL-type congenital anomalies.

Esophageal obstruction-prenatal detection rate and outcome

OBJECTIVE

Prenatal diagnosis of esophageal obstruction is believed to improve the outcome for the affected newborn. However, the prenatal detection rate is only 10-40%, the diagnosis is usually not made before the third trimester and the false-positive rate has been high. This study investigated the prenatal detection rate and time of prenatal diagnosis at our center and its influence on outcome. In addition, incidence, detection rate and accuracy of the diagnosis in a large non-selected population were determined.

METHODS

All cases diagnosed pre- or postnatally with esophageal obstruction and examined prenatally by ultrasound at the National Center for Fetal Medicine in Norway during 1987-2004 were evaluated.

RESULTS

Of 48 cases with esophageal obstruction, 21 (44%) were diagnosed prenatally (median, 32 + 0 weeks). All 21 had a small or empty stomach, 20/21 (95%) had polyhydramnios and 9/21 (43%) had a visible esophageal pouch. Associated anomalies were present in 38/48 cases (79%). The karyotype was abnormal in 11/48 cases (23%). Ten (21%) pregnancies with lethal fetal conditions were terminated. Two fetuses died in utero. Ten infants with associated anomalies died within 3 months after birth. The 26/48 (54%) survivors included 16/21 cases with a prenatal diagnosis of esophageal obstruction and 9/10 cases with isolated esophageal obstruction.

CONCLUSIONS

The clinical signs of polyhydramnios were the most important factors for prenatal detection of esophageal obstruction. Consequently, the time of diagnosis was late and the detection rate was low (44%). An increased awareness of the possibility of esophageal obstruction, leading to targeted examinations whenever the suspicion is raised during pregnancy, might improve the prenatal detection rate and thereby provide a possibility to improve the outcome. Of the cases with isolated esophageal obstruction, 90% survived, irrespective of prenatal diagnosis.

An overview of isolated and syndromic oesophageal atresia

Oesophageal atresia (OA) and/or tracheo-oesophageal fistula (TOF) are frequent malformations observed in approximately one in 3500 births. OA/TOF can be divided clinically into isolated OA (IOA) and syndromic OA (SOA) when associated with other features, the most frequent being cardiac, limb and vertebral malformations or anal atresia. SOA is observed in 50% of patients and can be subdivided into several causative groups comprising environmental agents, chromosomal disorders, malformative associations (CHARGE syndrome and VATER/VACTERL association), and other multiple congenital anomaly disorders. The observation of chromosomal disorders with SOA, as well as mouse models of OA provide support for the involvement of genetic factors in OA. Yet, epidemiological data (twin and family studies) do not support the major role of genetic factors in the majority of cases of IOA but rather a multifactorial model. However, several genes involved in SOA have been recently identified, namely N-MYC, SOX2, and CHD7 involved in Feingold (MIM 164280), anophthalmia-oesophageal-genital (MIM 600992) and CHARGE syndromes respectively (MIM 214800), suggesting that OA/TOF, at least in their syndromic forms, may be a highly genetically heterogeneous group.

H-type congenital tracheoesophageal fistula: University Of Iowa experience 1985 to 2005

OBJECTIVES

We review the diagnostic workup, associated disorders, surgical technique, and postoperative course of patients who underwent repair of H-type tracheoesophageal fistulas.

METHODS

We performed a retrospective chart review of patients who received a diagnosis of tracheoesophageal fistula at the University of Iowa.

RESULTS

Seven patients with an H-type tracheoesophageal fistula and a single patient with a missed proximal fistula associated with esophageal atresia were identified. Their symptoms included coughing with feeding, recurrent pneumonia, and episodic cyanosis. A delay in diagnosis was seen in 4 patients and ranged from 2.5 months to 5.9 years. In all patients, the diagnosis was made with an esophagogram. The level of the fistulas was between C5 and T3, and all were successfully repaired via a right cervical approach.

CONCLUSIONS

A high index of suspicion for an H-type tracheoesophageal fistula should be maintained in the presence of neonatal respiratory symptoms, as the condition can be associated with a delay in diagnosis. Repeat esophagograms and bronchoscopy may be required for diagnosis. In the postoperative period, airway obstruction is a potential risk; however, long-term difficulty with swallowing, respiration, and phonation was not observed.

Chromosomal anomalies in the aetiology of oesophageal atresia and tracheo-oesophageal fistula

Oesophageal atresia (OA) and tracheo-oesophageal fistula (TOF) are severe congenital anomalies of which the aetiology is largely unknown. Several chromosomal anomalies have been described in patients presenting with these anatomical malformations, but until now none of these has led to the identification of a single aetiological factor. This paper reviews the chromosomal abnormalities reported in cases of OA/TOF and serves as a starting point to identify chromosomal regions harbouring genes involved in the aetiology of OA/TOF.

Gastrointestinal malformations in Gorgan, North of Iran: epidemiology and associated malformations

The aim of this prospective study was to evaluate the prevalence and pattern of gastrointestinal malformations (GIM) among Iranian newborns in Gorgan, North of Iran. From 1998 through 2003, 37,951 live births in Dezyani hospital in Gorgan, North of Iran, were screened for gastrointestinal malformations. Clinical and demographic factors of diagnosed cases were recorded in a pre-designed questionnaire for analysis; sex, ethnicity, type of GIM and associated anomalies. The overall prevalence rate of gastrointestinal malformations was 10 per 10,000 births. The imperforate anus (5 per 10,000) was the commonest birth defect in gastrointestinal tract. The prevalence rate of GIM was 8.2 per 10,000 in males and 10.7 per 10,000 in females. According to the parental ethnicity, the prevalence rates of GIM were 6.7, 15.8 and 17.6 per 10,000 in Fars, Turkman, and Sistani, respectively. There were eight cases (21%) with associated anomalies. The prevalence rate of GIM in North of Iran is not similar to the previous studies in Iran and Middle East and ethnic background may be a causative factor in the rate of GIM in this area.

Oesophageal atresia with a terminal deletion of chromosome 2q37.1

We herein report the case of a newborn girl with oesophageal atresia associated with cardiac and gastrointestinal anomalies, including patent ductus arteriosus, tracheomalacia, and gastro-oesophageal reflux with hiatus hernia. In addition, she had a terminal deletion of the long arm of chromosome 2, with a breakpoint of 2q37.1. The patient died following a cardiac arrest at 90 days of age. No cause of death was identified at autopsy.

Oesophageal atresia, tracheo-oesophageal fistula, and the VACTERL association: review of genetics and epidemiology

Oesophageal atresia and/or tracheo-oesophageal fistula are relatively common malformations occurring in approximately 1 in 3500 births. In around half of the cases (syndromic oesophageal atresia), there are associated anomalies, with cardiac malformations being the most common. In the remainder (non-syndromic cases), oesophageal atresia/tracheo-oesophageal fistula occur in isolation. Data from twin and family studies suggest that genetic factors do not play a major role, and yet there are well-defined instances of this malformation where genetic factors clearly are important. This is highlighted by the recent identification of no fewer than three separate genes with a role in the aetiology of oesophageal atresia: those for Feingold syndrome (N-MYC), anophthalmia-oesophageal-genital (AEG) syndrome (SOX2), and CHARGE syndrome (CHD7). Additional support for genetic factors in this malformation comes from chromosomal studies and mouse models. This paper reviews current knowledge of the genetics and epidemiology of the different oesophageal atresia/tracheo-oesophageal fistula syndromes and associations.

The co-occurrence of congenital diaphragmatic hernia, esophageal atresia/tracheoesophageal fistula, and lung hypoplasia

BACKGROUND

Two severe birth defects, congenital diaphragmatic hernia (CDH) and esophageal atresia (EA) with or without tracheoesophageal fistula (TEF), have traditionally been analyzed separately in epidemiological studies. Lung hypoplasia (LH), part of the CDH spectrum, is not usually associated with EA/TEF, yet both are foregut malformations.

METHODS

We conducted an epidemiological study of two combinations of the defects in the population of 3,318,966 live births and stillbirths monitored from 1983 to 1996 by the California Birth Defects Monitoring Program (CBDMP).

RESULTS

A total of 433 cases had a Bochdalek type CDH/LH (0.13 per 1000 births), 893 had EA/TEF (0.27 per 1000 births), and 646 had LH (0.19 per 1000 births). Among them, 18 cases had CDH/LH with EA/TEF (0.005 per 1000 births), and 53 had EA/TEF and LH (0.02 per 1000 births); both prevalences are significantly higher than expected. Sixteen of 17 cases of CDH/LH with EA/TEF, and 34 of 40 cases of EA/TEF with LH were stillborn or died; 72% and 74%, respectively, had an autopsy. The male to female sex ratios were 1.43 and 1.13, respectively. In both groups, infants had similar proportions of additional severe defects, except for genitourinary and anal defects and syndromes/associations, which were more prevalent in the EA/TEF with LH group. We reviewed human studies and experimental animal models for factors reported to cause any combination of the defects.

CONCLUSIONS

Several genetic and environmental factors could affect the significant co-occurrence of the defects. Future studies should include storage of patients' biological materials for DNA analysis, karyotyping, and environmental exposure evaluation.

Epidemiology of oesophageal atresia and tracheo-oesophageal fistula in Hawaii, 1986–2000

The most common major birth defects affecting the oesophagus and trachea are oesophageal atresia (OA) and tracheo-oesophageal fistula (TOF). Epidemiological information on OA and/or TOF in the USA has been derived from only a few populations. Sixty-one cases of OA or TOF were identified through a population-based birth defects registry in Hawaii during 1986-2000. The relationship between various clinical and demographic factors and OA or TOF were examined. The rate of OA or TOF was 2.2 per 10,000 live births. The cases were 67.2% OA with TOF, 21.3% TOF alone, and 11.5% OA alone. Risk of OA or TOF was significantly higher among multiple births and live births with low birth weight and gestational age. The risk of OA or TOF was significantly higher for whites. The rate of OA or TOF was consistent with that reported elsewhere. The risk of the defects differed significantly between the major racial/ethnic groups in Hawaii. The impact of many factors on OA or TOF in Hawaii was similar to that reported elsewhere.

Isolated esophageal atresia and perinatal risk factors

Esophageal atresia (EA) is a relatively rare alimentary tract congenital anomaly. We studied perinatal risk factors of 90 live birth cases of isolated EA with (40 cases) or without (50 cases) tracheal fistula. We found sex ratios of 1.43 for total EA cases and 1.5 for both subgroups of EA with or without tracheal fistula. Evaluation of parity showed statistically significant values for low parity and for high multiparity for EA with and without tracheal fistula. Birth weight evaluation revealed statistically significant values for both subgroups. We did not find statistical significance both for maternal age and gestational age. The etiology of esophageal atresia is complex and heterogeneous and within each subgroup, apparently different etiologies may exist, resulting in differences in epidemiologic characteristics. Moreover, some causes linked to genetics and gene-environment interaction may be involved. We think that parity and low birth weight can be considered as risk factors for EA, and an accurate evaluation of reproductive history can be useful for the provision of genetic and perinatal counseling.

Prenatal diagnosis of esophageal atresia with the pouch sign

A 19-year-old primipara was referred to our center for a routine scan at 33 + 4 weeks' gestation. A visible but small stomach bubble (18 mm) was detected in the fetal abdomen, associated with a dilation of the esophagus with a tapering distal part. Direct visualization of filling and emptying of the proximal esophagus suggested the presence of obstruction. A cystic pouch in the region of the esophagus was observed to be full and empty in accordance with fetal swallowing. No other fetal anomalies were detected. Fetal biometric measurements were on the 10th percentile and polyhydramnios was detected. Esophageal atresia type I was suspected. Fetal karyotyping was declined by the parents, no therapy was given and the pregnancy continued until week 37 when a female baby was delivered following spontaneous labor. Esophageal atresia type I was radiographically confirmed. Bougienage was used for 8 weeks and esophageal anastomosis was successfully performed when the infant was 11 months old. No other anomalies were found and the child is currently in excellent health. The present case shows that the upper neck pouch sign may be a delayed manifestation present only in certain types of esophageal atresia. However, when it occurs it should prompt careful fetal examination as it is an important step in the diagnosis of esophageal atresia.

Gastrointestinal malformations, associated congenital abnormalities, and intrauterine growth

BACKGROUND

In contrast with other malformations, congenital anomalies of the gastrointestinal tract have been scarcely investigated.

METHODS

The prevalence of gastrointestinal malformations with special reference to associated disorders and intrauterine growth was retrospectively analyzed in the newborn infants admitted to the Neonatal Intensive Care Unit of the Department of Pediatrics, University of Pécs, Hungary, in the 14-year period between 1987 and 2000.

RESULTS

Of 4,241 neonates with gastrointestinal malformations, 241 (5.68%) had a total of 304 malformations (excluding Hirschsprung disease). In 133 patients, the gastrointestinal anomalies were observed as one of multiple malformations; a specific syndrome or association was diagnosed in 36 cases. Skeletal disorders were the most frequently associated anomalies. Intrauterine growth retardation was found in a large number of patients with both isolated and multiple gastrointestinal malformations (38.9% and 30.8%, respectively).

CONCLUSIONS

Gastrointestinal malformations often are complicated by skeletal anomalies and intrauterine growth retardation. The association among these disorders requires further investigation. However, from a practical point of view, this association should be considered in treating affected patients.

Neonatal surgical emergencies

Improvements in the diagnosis and treatment of congenital disorders have resulted in a change in surgical practice. Many conditions that formerly required corrective surgery immediately after birth are no longer surgical emergencies. Most babies with congenital anomalies that can be corrected by surgery are now stabilized and optimized before the procedure. This article focused on the more common conditions that require semi-elective or urgent surgery in the neonatal period. Salient features of each of these disorders were described. Factors unique to each of these conditions that can affect the anesthetic course of these children were discussed. Methods and techniques that may aid in the anesthetic management of these children were delineated.

Malrotation in conjunction with esophageal atresia/tracheo-esophageal fistula

Esophageal atresia or tracheo-esophageal fistula (EA/TEF) often occurs in association with a well-defined group of other anomalies. We report the prevalence of malrotation and other intestinal anomalies in a large data series comprising 632 nontrisomic infants with EA/TEF ascertained by the California Birth Defects Monitoring Program from January 1, 1983 to December 31, 1994. Consistent with findings reported previously in smaller case series, our findings showed a notable prevalence of imperforate anus (9.0%) and duodenal atresia (5.2%), among other gastrointestinal defects. They also showed a previously unrecognized high prevalence of intestinal malrotation (4.4%). Compared with other infants studied, the infants with EA/TEF and malrotation of the intestine had a higher proportion of other associated anomalies (in particular intestinal, central nervous system, vertebral and rib, renal and genital anomalies). These findings indicate that intestinal malrotation is more common in infants with EA/TEF than is generally perceived, and that intestinal malrotation in an infant with EA/TEF is associated with a higher burden of additional congenital anomalies, suggesting that this group of infants may have more pervasive developmental deficits and poorer prognosis than has previously been recognized.

Oesophageal atresia, related malformations, and medical problems: a family study

Oesophageal atresia (OA) and tracheo-oesophageal fistula (TOF) are life-threatening malformations of generally undefined cause. Previous reports of familial cases suggest a genetic contribution. The pattern of inheritance appears non-Mendelian, i.e., multifactorial. Individuals with OA/TOF often have other malformations and medical problems. The aim of this study was to determine the association in OA/TOF cases and healthy control subjects of associated malformations, midline defects, and medical conditions. We also investigate the relationships of these conditions in the relatives of the cases and controls. The results show that infants with OA/TOF frequently have VACTERL anomalies (vertebral, 17%; anal, 12%; cardiac, 20%; renal, 16%; limb, 10%) and other midline defects (cleft lip and palate, 2%; sacral dysgenesis, 2%; urogenital anomalies, 5%). The following medical problems were also reported: oesophageal dysmotility, 21%; gastro-oesophageal reflux, 22%; chest infections, 6%; and autonomic dysfunction, 0.5%. The first-degree relatives of children with OA are much more likely to have one of the aforementioned malformations or medical conditions when compared with the control group: one or more VACTERL anomalies (P < 0.01), gastro-oesophageal reflux (P < 0.05), recurrent respiratory infections (P < 0.05), and autonomic dysfunction (P < 0.001). The more distant relatives also show an increased incidence of such problems although in this case the data must be viewed with caution. The results confirm that the associated malformations and related medical problems occur significantly more frequently in the relatives of individuals with OA/TOF. These families may prove valuable for linkage analysis in an attempt to determine the genetics of OA/TOF.

Retinoic acid-induced caudal regression syndrome in the mouse fetus

Caudal regression syndrome (CRS) comprises developmental anomalies of the caudal vertebrae, neural tube, urogenital and digestive organs, and hind limbs, the precursors of all of which are derived from the caudal eminence. Although the syndrome is well recognized, the etiology and pathogenetic mechanisms are poorly understood. Genetic and experimental models may provide some important clues to the early events that precede the dysmorphogenesis in CRS. The objectives of this study were to determine the susceptible stages for induction of CRS and to ascertain the early events that precede the development of this syndrome in a mouse model. Single oral doses of 100, 150, or 200 mg/kg retinoic acid (RA) were administered to TO mice on one of Gestation Days (GD) 8 to 12, and fetuses were observed on GD 18. All doses administered on GD 8 or 9 resulted in CRS in a large number of survivors. Agenesis of the tail, caudal vertebral defects, spina bifida occulta/aperta, imperforate anus, rectovesicle or rectourethral fistula, renal malformations, cryptorchidism, gastroschisis, and limb malformations, including the classical mermaid syndrome (sirenomelia), were characteristic features of this animal model. Several craniofacial malformations accompanied CRS in the GD 8 treatment group. Chronologic examination of treated embryos at early stages revealed pronounced cell death in the caudal median axis, hindgut, and neural tube and consequently, failure of development of the tail bud in the high-dose groups. In the 100 mg/kg RA group, patches of hemorrhage occurred initially that subsequently coalesced into large hematomas and the tail progressively regressed. Histologic examination revealed the onset and progression of hemorrhage, edema, and cell death in these embryos. Transillumination and histologic preparations also revealed dilation of the caudal neural tube in the prospective CRS embryos. Thus, a combination of cell death, vascular disruption, and tissue deficiency appears to be the highlight of caudal regression in this model. Symmelia appeared to be due to failure of fission or due to the merger of limb fields rather than a result of fusion of two limb buds. The data are also indicative of caudal agenesis in the high-dose RA groups and caudal regression due to a combination of vascular disruption, edema, and cell death in the lower dose groups of TO mouse embryos.