Gastroschisis with omphalomesenteric artery remnant, colonic atresia and arthrogryposis multiplex congenita

Pathogenic implications of remnant vitelline structures in gastroschisis

PURPOSE

The pathogenesis of gastroschisis is unknown. It may be helpful in understanding its pathogenesis to know the structural relationships among umbilical components including umbilical vessels, urachus, and vitelline structures, and thus, the authors investigated the remnants of vitelline structures in a series of cases of gastroschisis.

METHODS

Medical records of 41 cases with gastroschisis treated in our institute from 1979 to 2009 were retrospectively reviewed.

RESULTS

Paraumbilical bands, possible remnants of vitelline structures, were observed in 4 cases (9.8%). All 4 bands were attached to the skin edge of the abdominal defect without incorporation into the umbilical cord. The band ended at the mesentery in 3 cases and at the antimesenteric site of the ileum in the remaining case. Histologic findings showed fibrous tissues in all cases. One was possibly associated with the development of colonic atresia. Another was noticed after silo reduction when herniated bowels became strangulated by the band. The other 2 cases were uncomplicated.

CONCLUSIONS

Our findings may support the recently proposed hypothesis that the developmental failure of the yolk sac and related vitelline structures to merge with or to be incorporated into the umbilical stalk might be associated with the pathogenesis of the abdominal wall defect in gastroschisis. Paraumbilical bands derived from vitelline structures may possibly cause intestinal ischemia prenatally or postnatally.

Is there epidemiologic evidence to support vascular disruption as a pathogenesis of gastroschisis?

Gastroschisis is a congenital defect of the abdominal wall that occurs most commonly in the offspring of young women. The defect is often hypothesized to result from vascular disruption in the early embryo. We measured the associations between maternal vasoactive exposures in pregnancy, as possible markers of vascular disruption, and gastroschisis risk, using data collected as part of the National Birth Defects Prevention Study. Study participants included mothers of births from October 1997 to December 2003 in 10 states. The mothers of 514 gastroschisis cases were matched by age at delivery and state to 3,277 non-malformed controls and compared for periconceptional smoking and use of vasoconstrictors, non-steroidal anti-inflammatory drugs (NSAIDs), and vasodilators. Multivariable-adjusted odds ratios (ORs) and 95% confidence intervals (CI) were estimated from conditional logistic regression. Case mothers were more likely than control mothers to smoke (OR = 1.5, 95% CI = 1.2-1.9) and report use of non-aspirin NSAIDs (1.4, 1.1-1.7) and anti-hypertensive vasodilators (2.6, 0.9-8.0), but not vasoconstrictive decongestants (1.0, 0.7-1.4). Cigarette smoking had little effect on gastroschisis risk in mothers <25 years of age, but the OR was 3.0 (1.8-5.0) for those >or=25 years. Likewise, ORs were greatest in the older women for use of non-aspirin NSAIDs (1.6, 1.0-2.6) and bronchodilators (3.0, 1.8-5.0). These findings suggest that, overall, vasoactive risk factors play a minor role in the etiology of gastroschisis, and do not support the vascular disruption hypothesis. However, the observation that increased ORs for some vasoactive exposures were confined to older women raises the question of whether inherent maternal factors might influence risk.

Development of gastroschisis: review of hypotheses, a novel hypothesis, and implications for research

Gastroschisis, a ventral body wall defect, is a continuing challenge and concern to researchers, clinicians, and epidemiologists seeking to identify its cause(s) and pathogenesis. Concern has been renewed in recent years because, unlike most other birth defects, rates of gastroschisis are reportedly increasing in many developed and developing countries. No tenable explanation or specific causes have been identified for this trend. Rates of gastroschisis are particularly high among pregnancies of very young women. Such an intriguing association, not observed to this degree with other birth defects, may afford clues to the defect's cause. Understanding the causes of gastroschisis may provide insight to the defect's origin. In pursuing such causal studies, it would be helpful to understand the embryogenesis of gastroschisis. To date, four main embryologic hypotheses have been proposed: (1) Failure of mesoderm to form in the body wall; (2) Rupture of the amnion around the umbilical ring with subsequent herniation of bowel; (3) Abnormal involution of the right umbilical vein leading to weakening of the body wall and gut herniation; and (4) Disruption of the right vitelline (yolk sac) artery with subsequent body wall damage and gut herniation. Although based on embryological phenomena, these hypotheses do not provide an adequate explanation for how gastroschisis would occur. Therefore, we propose an alternative hypothesis, based on well described embryonic events. Specifically, we propose that abnormal folding of the body wall results in a ventral body wall defect through which the gut herniates, leading to the clinical presentation of gastroschisis. This hypothesis potentially explains the origin of gastroschisis as well as that of other developmental defects of the ventral wall.

Risk for gastroschisis in primigravidity, length of sexual cohabitation, and change in paternity

BACKGROUND

Maternal epidemiologic similarities between gastroschisis and preeclampsia have led to the objective of evaluating the risk for gastroschisis related to primigravidity, change in paternity, and length of cohabitation, considered as risk factors for preeclampsia.

METHODS

The subjects were 288 newborns with isolated gastroschisis and 576 normal controls, matched by maternal age. They were ascertained in the Estudio Colaborativo Latino Americano de Malformaciones Congenitas hospital network of 10 South American countries between 1982 and 2005. Epidemiologic variables were compared among controls, between primigravidas and multigravidas, between multigravidas who had and had not changed partners, and between mothers with short and long cohabitation times with their partners. Risks associated with primigravidity, short cohabitation time, and changing paternity, as well as their combinations, were calculated. An eventual interaction between maternal age and the three risk factors was assessed.

RESULTS

Only a short cohabitation time showed a significant OR for gastroschisis (OR = 2.36, 95% CI: 1.52-3.66, p < .001), whereas ORs were not significant for primigravidity (OR = 1.40, 95% CI: 0.84-2.35, p = .192) nor for changing paternity (OR = 1.20, 95% CI: 0.49-3.10, p = .752). The risk was highest for multigravidas who had changed partners (OR = 8.71, 95% CI: 2.93-21.12, p < .001), followed by multigravidas who had not changed partners (OR = 3.99, 95% CI: 1.07-15.43, p = .049), and by primigravidas (OR = 3.02, 95% CI: 1.58-5.76, p = .001), all having cohabitated for a short time. Maternal age did not modify these risks.

CONCLUSIONS

Three groups at risk for a child with gastroschisis were identified, all having in common a short cohabitation time. Antigenic or "modern" lifestyle-related factors might be involved in the origin of gastroschisis.

Gastroschisis associated with cleft lip and palate

Gastroschisis is a common congenital abdominal wall defect. Rarely, it is associated with extraabdominal midline congenital anomalies. Oral clefts are the commonest craniofacial congenital midline defects. They can be associated with other midline defects like omphalocele. We believe these are the first 3 case reports of gastroschisis and cleft palate occurring in the same patient.

Teratogen update: pseudoephedrine

Pseudoephedrine is contained in decongestants such as the Sudafed line of products. It is an alpha-adrenergic receptor agonist, which causes blood vessel constriction, including the therapeutic effect of reducing airflow resistance in the nasal cavity. Pseudoephedrine is one of the most commonly used medications in pregnancy, with an estimated 25% of women exposed. It has been demonstrated that alpha-adrenergic receptor agonists slow uterine blood flow, but their effects have not been studied in relation to most reproductive outcomes in animals or humans. Two analyses of health maintenance organization pharmacy data identified 9 malformed infants among 902 first-trimester pseudoephedrine exposures, suggesting no association with birth defects overall; however, studies of such data sets often lack sufficient power to identify risks for specific birth defects. The related compounds, epinephrine, ephedrine, and phenylephrine, have been associated with hemorrhages and cardiovascular and limb malformations in animal models. Risk of ventricular septal defects was associated with decongestant use in pregnant women in 1 recent study. The vasoconstrictive effects of these drugs raise the hypothesis that their use in early pregnancy might increase the risk of vascular disruption defects. Case-control studies, which often do have power to identify risks related to specific birth defects, have explored this hypothesis. Decongestant use in the first trimester has been associated with small increases in risks of 3 defects thought to arise, at least in some instances, from vascular disruption-gastroschisis, small intestinal atresia, and hemifacial microsomia. These findings are somewhat consistent in terms of magnitude of effect and suggest that risks are even greater among women also exposed to the vasoconstrictive effects of cigarette smoking. There are, however, limitations to these studies, including the possibilities of inaccurate recall of exposures and confounding by indication. In addition, the majority of decongestant use is in oral form and the question of whether intranasal formulations carry risk has not been adequately addressed.

Atresia of the colon

BACKGROUND/PURPOSE

Colonic atresia (CA) is one of the rarest causes of neonatal intestinal obstructions, and no large series can be reported. Therefore, we did perform a retrospective clinical trial to delineate our CA cases and carry out a literature survey.

METHODS

We reviewed the charts of CA cases treated in our center between 1992 and 2002. We aimed to collect all reported cases in Medline, and personal communications with the authors of published series were used to reach the missing data.

RESULTS

The chart review revealed 9 newborns with CA treated in our center (6 cases of type III, 2 cases of type II, and 1 case of type IV). These accounted for 3.7% of all gastrointestinal atresias managed in our center. Of the CA cases, 3 were isolated and 6 had at least one or more associated congenital anomalies. The preferred surgical technique at the initial treatment of CA was performing a proximal stoma and distal mucous fistula in an average of postnatal 59.4 hours. The literature survey enabled us to reach 224 cases of CA, including our cases.

CONCLUSIONS

Because of the low incidence of CA, delay in diagnosis and treatment may occur. The mortality is statistically higher when the surgical management is performed after 72 hours of age. However, the prognosis of CA is satisfactory if diagnosis and surgical management could be made promptly and properly.

Epidemiology of gastroschisis in metropolitan Atlanta, 1968 through 2000

BACKGROUND

An increase in the rate of gastroschisis has been documented by birth defects surveillance systems in the United States and in other countries. This study sought to evaluate historical trends in the rate of gastroschisis in Atlanta, Georgia, and to describe the epidemiology of gastroschisis over 33 years.

METHODS

Gastroschisis cases were identified through the Metropolitan Atlanta Congenital Defects Program (MACDP) from 1968 through 2000. Poisson regression techniques were used to evaluate trends over time. Data on covariates were compared for three maternal age groups (< or =19, 20-24, and > or =25 years).

RESULTS

From 1968 through 1975, the rate of gastroschisis was stable at 0.8 per 10,000 births. After 1975, the rate of gastroschisis was 2.3 per 10,000 births with no significant increase observed from 1976 through 2000. The rate of gastroschisis was six times higher among teenage mothers compared with mothers > or =25 years of age. Affected infants born to teenage mothers were less likely to be born to Black mothers compared to White mothers (rate ratio [RR], 0.4; 95% confidence interval [CI], 0.2-0.6). This was also true for mothers 20-24 years of age (RR, 0.5; 95% CI, 0.3-0.8) but not for mothers 25 years of age or older (RR, 1.6; 95% CI, 0.9-2.7).

CONCLUSIONS

An increase in the rate of gastroschisis was observed in the mid-1970s, but no temporal trend has been observed since that time. In light of recent reports of an increasing prevalence of gastroschisis in the United States, continued monitoring of this birth defect is warranted.