Gastrointestinal Tract Anomalies

Gastroschisis

Gastroschisis is a paraumbial defect involving all layers of the abdominal wad it is usually night sided with the small bowel Wenn triqugh the defect Rarely the stomach or other organs may be muhed in the hemation. Rarely left sided defects are seen

Incidence: 1.75-25/10000 live births with a male predominance

Pathogenesis: The defect is due to the premature atrophy of right umbilical vein occurring at 28-33 days post conception resulting in ischemis to surrounding tissues, leading to the development of the defect in anterior abdominal wall

Associated anomalies: Seen in7-30% cases. They include Anencephaly, Cleft lip & palate, Atrial septal defect, Ectopia cordis, Diaphragmatic hemin & Scoliosis

Diagnosis: The diagnosis of Gastroschisis can be made as early as 12 menstrual weeks with the characteristic feature of mhultiple loops of bowel seen outside abdomen

Prognosis: It occurs sporadically & has no genetic association or recuurence risk. Of all the abdominal defects, Gastroschisis has the best prognosis because of lack of association with other anomalies. In uncomplicated cases the survival rate is 100%

Omphalocele

Omphalocele is a defect in the anterior abdominal wall with extraction of the abdominal contents into the base of the umbilical cord. The herniated mass is covered by parietal peritoneum and amnion with whartons jelly intervening between the two membranes

Incidence: 2.5 in 10,000 live births with male-female ratio of 11

Pathogenesis: Due to persistence of the primitive body stalk with failure of bowel to return to the abdomen beyond 12 menstrual weeks

Associated anomalies: Seen in 50 88% of cases, with chromosomal anomalies seen in 40-60% The most common are trisomy 18, 13 & 21. It is also associated with cardiac anomalies ni 50% of cases They include VSD. Tetrology of fallot Pulmonary artery stenosis, Courctation of aoda & Transposition of Beckwith-Wiedemann syndrome and cloacal extrophy

Diagnosis: Can be made by 12 menstrual weeks. The characteristic findings in an amphalocele include the presence of an anterior abdominal mass at the site of the cord insertion with associated ascites and covering membrane. Cord insertion at the apex should be confirmed

Prognosis: Neonatal morbidity and mortality rates are high when associated with anomalies. The size of the delect affects the morbidity There is <1% recurrence risk associated with omphaloceles.