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Updates in: Abdominal Wall Defects

Bhanumathi Lakshminarayanan¹, Kokila Lakhoo²

¹Department of Paediatric Surgery, Leeds General Infirmary, Leeds Teaching Hospitals NHS Trust, Leeds, United Kingdom

² Department of Paediatric Surgery, John Radcliffe Hospital, Oxford, United Kingdom

 

Correspondence:

Bhanumathi Lakshminarayanan

Department of Paediatric Surgery

Leeds General Infirmary, Leeds Teaching Hospitals NHS Trust

Great George St, Leeds LS1 3EX, UK

E-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

 

Abstract

Abdominal wall defects seen in children include gastroschisis, exomphalos, exstrophy, umbilical hernias and patent vitellointestinal duct or patent urachus. The commonest defects managed in the newborn period are gastroschisis and exomphalos. Umbilical hernias result from a failure of closure of the umbilical muscle fascia, have a different natural history to the conditions that require management in the neonatal period. These various conditions in the paediatric age group are discussed along with their management and challenges.

Keywords: congenital, abdominal wall defects, gastroschisis, exomphalos, exstrophy, umbilical hernia

 

Introduction

The incidence of congenital abdominal wall defects, especially gastroschisis has increased over the last few decades. As our prenatal diagnosis of these conditions has evolved, there is an increasing demand for tertiary level management of these conditions to improve the outcome. This review article highlights the current practical management of complex congenital abdominal wall defects and the challenges faced. The management of other less common abnormalities like exstrophy, patent vitellointestinal duct, and urachus is also discussed.

Gastroschisis

Gastroschisis is the presence of intestine outside the abdominal cavity through a defect in the anterior abdominal wall, often through a small defect to the right of the umbilical cord. This requires surgical correction in the newborn period.

The present incidence of gastroschisis is 4.42 per 10000 live births [1]. The incidence is higher in young mothers below 20 years of age and primigravida [2]. Initial reports of antenatal diagnosis of this condition using ultrasound were described in 1970’s [3]. The use of ultrasound has evolved in these group to help determine the complexity and assist in the timing of delivery [4]. Goetzinger et al use a value of intraabdominal bowel dilatation over 14mm as predictive of bowel atresia [5]. Other ultrasound features that have been consistently studied in the perinatal management of gastroschisis include intrauterine growth restriction (IUGR), abdominal circumference, stomach herniation and extraabdominal bowel dilatation. Of these features, the ones that are more predictive is Intraabdominal bowel dilation and IUGR [6].

The timing of delivery is another controversial area in the management of gastroschisis. There is a well known increased risk of foetal death for pregnancy that is allowed to carry on beyond 36 weeks gestation of 1.28 per 100 [7]. Most centres will induce labour at 37 weeks of gestation. In a study of 153 pregnancies with gastroschisis comparing induction of labour at 37 weeks to spontaneous onset of labour, there was reduced risk of sepsis, bowel damage and neonatal death in the induced group [8]. There is a significantly high number of patients requiring caesarean section and in the above study, this was 20% in both the induced labour and expectant labour groups [8]. After delivery, the gastroschisis patients can be risk stratified into either simple or complex. Simple gastroschisis have a good condition of their bowel and can be managed with primary closure or preformed silo application. In complex gastroschisis, the gastroschisis is complicated by atresia, ischemia, necrosis or closing defect. A staged surgical approach might become necessary and could lead to gastrointestinal complications. Complex gastroschisis accounts for 10% of all gastroschisis and has implications for the health care service due to the significantly prolonged length of hospital stay, inpatient mortality, gastrointestinal complications and sepsis [9]. Two-thirds of cases of complex gastroschisis patients have intestinal atresia and will require management with silo application to improve bowel recovery before bowel resection or stoma formation is considered [10].

Primary closure of gastroschisis when possible has the advantage of early discharge from the hospital, less intensive care bed requirement and achieve full feeds earlier [11]. Silo closure, on the other hand, decreases the risk of abdominal compartment syndrome, reduces the need for postoperative ventilation and decreases the incidence of necrotising enterocolitis and ischaemic complications of the bowel [11]. Preformed silo application is not without its complications and the most frequent problem being falling out, with also the risk of causing ischaemia to the bowel due to poor perfusion from a narrow base [12, 13].

Gastroschisis has a good overall outcome in the developed countries with survival reaching 96% [14]. This is due to improved antenatal diagnosis, neonatal surgical care, availability of total parenteral nutrition and multidisciplinary approach to complex gastroschisis. However, in low income countries, the mortality is very high with poor access to parenteral nutrition available in only 36% and access to neonatal intensive care available only in 19% of the times [15]. The mortality in some countries like Uganda reaches 100%, the commonest cause of death being septicaemia [16].

Exomphalos

Exomphalos is a neonatal abdominal wall defect due to the failure of the intestine to return to the abdominal cavity [17]. The incidence of exomphalos is 4.4 per 10000 births [18]. The majority of the foetuses will have a chromosomal abnormality and other associated significant abnormalities. More than 80% of cases lead to either medical termination of pregnancy or foetal loss [19]. Similar to gastroschisis, exomphalos is diagnosed antenatally. Associated foetal anomalies and evidence of chromosomal abnormalities aid in further discussion with the families about medical termination. The ultrasound ratio of the circumference of the exomphalos to the abdominal circumference predicts if the defect is minor or major [20]. A larger ratio predicts the herniation of liver in the sac and correlates with respiratory insufficiency [20]. There is an increased risk of preterm delivery which increases the mortality rate.

Management of exomphalos postnatally depends on the size of the defect, gestational age, respiratory insufficiency and associated anomalies. In exomphalos minor, where the defect is less than 5cm, primary closure of fascia is easily achieved. Exomphalos major can be managed either with primary closure, staged closure or delayed closure. A fascial closure with a patch might become necessary in an exomphalos major defect during the primary closure. The various patches available to use can be either non-biodegradable like Teflon and Gore-Tex or biodegradable like Surgisis and Permacol [21]. A staged approach is helpful in the management of large defects and giant exomphalos by reducing the risk of abdominal compartment syndrome, minimising the ventilatory requirement and improves survival [21].

With delayed closure, the sac is allowed to epithelialise and the process can be accelerated with the application of topical antiseptic or silver based solutions. Newborns can be fed early and have a shorter length of hospital stay. The fascial closure is aimed for 6 to 12 months of age. This delayed fascial closure appears to be better tolerated as the respiratory function improves with age. The mortality rate is higher in exomphalos when compared with gastroschisis due to their associated anomalies and pulmonary hypoplasia. The survival rate in the neonatal period is 80% and during the first year of life a further 15% cases die due to pulmonary insufficiency or associated major anomalies [22].

Bladder and cloacal exstrophy

Exstrophy results with the failure of formation of the lower part of the anterior abdominal wall leading to an exposed bladder. The exstrophy complex ranges from epispadias to weak bladder neck to a fully exposed posterior wall of the bladder. These abnormalities are usually isolated. The cloacal exstrophy is more severe associated with an imperforate anus, exomphalos and is typically associated with other anomalies. The incidence of this anomaly is 1 in 200000 births [23].

The main treatment includes prevention of the drying of the bladder plate using occlusive silicone dressing, the closure of bladder with bladder neck reconstruction, epispadias repair and future urinary reconstruction to increase bladder capacity such as augmentation. Various surgical techniques such as radical soft tissue mobilisation (Kelly procedure) and modern staged repair have been described with equally good results. Where the closure is delayed, a pelvic osteotomy is required to allow bladder closure [24]. With adequate surgical and postoperative management in specialised centres, 80% of patients will achieve urinary continence and up to 70% of cases will require surgical procedures to increase bladder capacity [25]. In spite of the complexity of the condition, the majority of them have a good quality of life.

Umbilical hernia

An umbilical hernia develops when there is a delay in closure of the umbilical fascial ring after the detachment of the umbilical cord. The delay in closure can sometimes take up to 4 to 5 years of age. Children of African origin have a higher incidence of umbilical hernia and are more prone to have large hernias. They are mostly asymptomatic and the reason for surgical intervention is usually cosmetic. Repair can be done after 4 years of age if there is no evidence of spontaneous closure. The risk of presenting acutely with an incarceration is extremely low to the range of 1 in 3000 to 1 in 11000 cases [26]. The risk of evisceration of bowel through spontaneous rupture of the skin is also reported, but these are very rare [27]. Umbilical hernia repair in children has a very good outcome, with 2% risk of recurrence and 2% postoperative morbidity such as wound infection and haematoma [28]. Large umbilical hernias might require umbilicoplasty to create a neo-umbilicus [29]. Rectus sheath block is considered effective in reducing post-operative pain after an umbilical hernia repair, but will require appropriate expertise and training to administer this [30].

Patent urachus and patent vitellointestinal duct Vitello-intestinal duct and urachus are embryological precursors of intestine and bladder respectively. Occasionally, they can persist even after the functional structures are formed and communicate externally through a fistula in the umbilicus due to the failure of obliteration of these by the 7th week of life. They can become obvious during the neonatal period and in some cases can present later in life with persistent umbilical discharge or recurrent umbilical infections. In the general paediatric population, the prevalence of urachal anomaly is around 1%, amongst these patent urachus account to around 1.5% of cases [31]. Children with urachal abnormalities should be evaluated for the presence of other urogenital anomalies. They will require evaluation using ultrasound of the renal tract and a voiding cystourethrogram [32, 33]. There is a high incidence of associated vesicoureteral reflux (65%) [34]. There are reports of patent urachus in association with urethral atresia and posterior urethral valves [35, 36]. These patients when evaluated have a high incidence of prune-belly syndrome [35]. Patent urachus in these circumstances act as a pop off valve and are protective to the kidneys. The urachus can also be used as a conduit that can be dilated and used for catheterisation of the bladder. If the patent urachus is isolated with no associated urinary abnormalities excision is recommended to prevent recurrent umbilical infections and remove the risk of late malignant transformation. The commonest location for any neoplastic change in the urachus is near the dome of the bladder and are usually adenocarcinoma [37].

Patent vitellointestinal ducts usually are isolated abnormalities. There is a higher incidence in males with a ratio of 4:1 [38]. They present with persistent feculent discharge from the umbilicus. In some cases, the discharge can be high output leading to electrolyte imbalance and death [38]. A bulky umbilical cord at birth should raise suspicion of the presence of bowel or a vitellointestinal duct within the cord. Failure to recognise this can lead to serious complications such as perforation of the intestine in an attempt to umbilical venous catheterisation [39]. These cases are managed with exploration of the umbilicus and excision of the patent duct.

Summary

Abdominal wall defects in children can range from a simple umbilical hernia to more complex giant exomphalos to exstrophy complex with chromosomal abnormalities. A good understanding of the embryology, anatomy, presentation and management is essential to identify resources required in the healthcare system, training needs and improve outcomes for these patients.

 

 

References:

1. Kirby RS, Marshall J, Tanner JP, Salemi JL, Feldkamp ML, Marengo L, et al. Prevalence and correlates of gastroschisis in 15 states, 1995 to 2005. Obstet Gynecol. 2013 Aug;122(2 Pt 1):275-81.

2. Tan KH, Kilby MD, Whittle MJ, Beattie BR, Booth IW, Botting BJ. Congenital anterior abdominal wall defects in England and Wales 1987-93: retrospective analysis of OPCS data. BMJ. 1996 Oct 12;313(7062):903-6.

3. Grossman M, Fischermann EA, German J. Sonographic findings in gastroschisis. J Clin Ultrasound. 1978 Jun;6(3):175-6.

4. Overton TG, Pierce MR, Gao H, Kurinczuk JJ, Spark P, Draper ES, et al. Antenatal management and outcomes of gastroschisis in the U.K. Prenat Diagn. 2012 Dec;32(13):1256-62.

5. Goetzinger KR TM, Longman RE, Huster KM, Odibo AO, Cahill AG. Sonographic predictors of postnatal bowel atresia in fetal gastroschisis. Ultrasound Obstet Gynecol. 2014;43(4):420-5.

6. Page R, Ferraro ZM, Moretti F, Fung KF. Gastroschisis: antenatal sonographic predictors of adverse neonatal outcome. J Pregnancy. 2014;2014:239406.

7. South AP, Stutey KM, Meinzen-Derr J. Metaanalysis of the prevalence of intrauterine fetal death in gastroschisis. Am J Obstet Gynecol. 2013 Aug;209(2):114 e1-13.

8. Baud D, Lausman A, Alfaraj MA, Seaward G, Kingdom J, Windrim R, et al. Expectant management compared with elective delivery at 37 weeks for gastroschisis. Obstet Gynecol. 2013 May;121(5):990-8.

9. Arnold MA, Chang DC, Nabaweesi R, Colombani PM, Bathurst MA, Mon KS, et al. Risk stratification of 4344 patients with gastroschisis into simple and complex categories. J Pediatr Surg. 2007 Sep;42(9):1520-5.

10. Emil S, Canvasser N, Chen T, Friedrich E, Su W. Contemporary 2-year outcomes of complex gastroschisis. J Pediatr Surg. 2012 Aug;47(8):1521-8.

11. Weil BR LC, Rescorla FJ. The jury is still out: changes in gastroschisis management over the last decade are associated with both benefits and shortcomings. J Pediatr Surg. 2012;47(1):119-24.

12. Aldrink JH CD, Nwomeh BC. Variability in gastroschisis management: a survey of North American pediatric surgery training programs. J Surg Res. 2012;176(1):159-63.

13. Lobo JD KA, Davis RP, Segura BJ, Alpert H, Teitelbaum DH, Geiger JD, Mychaliska GB. No free ride? The hidden costs of delayed operative management using a spring-loaded silo for gastroschisis. J Pediatr Surg. 2010;45(7):1426-32.

14. Durfee SM, Benson CB, Adams SR, Ecker J, House M, Jennings R, et al. Postnatal outcome of fetuses with the prenatal diagnosis of gastroschisis. J Ultrasound Med. 2013 Mar;32(3):407-12.

15. Wright NJ, Zani A, Ade-Ajayi N. Epidemiology, management and outcome of gastroschisis in Sub-Saharan Africa: Results of an international survey. Afr J Paediatr Surg. 2015 Jan-Mar;12(1):1-6.

16. Ford K, Poenaru D, Moulot O, Tavener K, Bradley S, Bankole R, et al. Gastroschisis: Bellwether for neonatal surgery capacity in low resource settings? J Pediatr Surg. 2016 Aug;51(8):1262-7.

17. Sadler TW. The embryologic origin of ventral body wall defects. Semin Pediatr Surg. 2010 Aug;19(3):209-14.

18. Boyd PA, Tonks AM, Rankin J, Rounding C, Wellesley D, Draper ES. Monitoring the prenatal detection of structural fetal congenital anomalies in England and Wales: register-based study. Journal of medical screening. [Research Support, Non-U.S. Gov't]. 2011;18(1):2-7.

19. Lakasing L CS, Davenport M, Patel S, Nicolaides KH. Current outcome of antenatally diagnosed exomphalos: an 11 year review. J Pediatr Surg. 2006;41(8):1403-6.

20. Kleinrouweler CE KC, van Zalen-Sprock MM, Mathijssen IB, Bilardo CM, Pajkrt E. Characteristics and outcome and the omphalocele circumference/abdominal circumference ratio in prenatally diagnosed fetal omphalocele. Fetal Diagn Ther. 2011;30(1):60-9.

21. van Eijck FC AD, Hoogeveen YL, Wijnen RM. Past and current surgical treatment of giant omphalocele: outcome of a questionnaire sent to authors. J Pediatr Surg. 2011;46(3):482-8.

22. van Eijck FC HY, van Weel C, Rieu P, Wijnen RM. Minor and giant omphalocele: long-term outcomes and quality of life. J Pediatr Surg. 2009;44(7):1355-59.

23. Evans JA, Darvill KD, Trevenen C, Rockman-Greenberg C. Cloacal exstrophy and related abdominal wall defects in Manitoba: incidence and demographic factors. Clin Genet. 1985 Mar;27(3):241-51.

24. Baird AD, Sponseller PD, Gearhart JP. The place of pelvic osteotomy in the modern era of bladder exstrophy reconstruction. J Pediatr Urol. 2005 Feb;1(1):31-6.

25. Woodhouse CR, North AC, Gearhart JP. Standing the test of time: long-term outcome of reconstruction of the exstrophy bladder. World J Urol. 2006 Aug;24(3):244-9.

26. Ireland A, Gollow I, Gera P. Low risk, but not no risk, of umbilical hernia complications requiring acute surgery in childhood. J Paediatr Child Health. 2014 Apr;50(4):291-3.

27. Thomson WL, Wood RJ, Millar AJ. A literature review of spontaneous evisceration in paediatric umbilical hernias. Pediatr Surg Int. 2012 May;28(5):467-70.

28. Zendejas B, Kuchena A, Onkendi EO, Lohse CM, Moir CR, Ishitani MB, et al. Fifty-three-year experience with pediatric umbilical hernia repairs. J Pediatr Surg. 2011 Nov;46(11):2151-6.

29. Komlatse AN, Anani MA, Azanledji BM, Komlan A, Komla G, Hubert T. Umbilicoplasty in children with huge umbilical hernia. Afr J Paediatr Surg. 2014 Jul-Sep;11(3):256-60.

30. Rajwani KM, Butler S, Mahomed A. In children undergoing umbilical hernia repair is rectus sheath block effective at reducing post-operative pain? Best evidence topic (bet). Int J Surg. 2014 Dec;12(12):1452-5.

31. Gleason JM, Bowlin PR, Bagli DJ, Lorenzo AJ, Hassouna T, Koyle MA, et al. A comprehensive review of pediatric urachal anomalies and predictive analysis for adult urachal adenocarcinoma. J Urol. 2015 Feb;193(2):632-6.

32. Yapo BR, Gerges B, Holland AJ. Investigation and management of suspected urachal anomalies in children. Pediatr Surg Int. 2008 May;24(5):589-92.

33. Cilento BG, Jr., Bauer SB, Retik AB, Peters CA, Atala A. Urachal anomalies: defining the best diagnostic modality. Urology. 1998 Jul;52(1):120-2.

34. Fox JA, McGee SM, Routh JC, Granberg CF, Ashley RA, Hutcheson JC, et al. Vesicoureteral reflux in children with urachal anomalies. J Pediatr Urol. 2011 Dec;7(6):632-5.

35. Gonzalez R, De Filippo R, Jednak R, Barthold JS. Urethral atresia: long-term outcome in 6 children who survived the neonatal period. J Urol. 2001 Jun;165(6 Pt 2):2241-4.

36. Atobatele MO, Oyinloye OI, Nasir AA, Bamidele JO. Posterior urethral valve with unilateral vesicoureteral reflux and patent urachus: A rare combination of urinary tract anomaliess. Urol Ann. 2015 Apr-Jun;7(2):240-3.

37. Szarvas T, Modos O, Niedworok C, Reis H, Szendroi A, Szasz MA, et al. Clinical, prognostic, and therapeutic aspects of urachal carcinoma-A comprehensive review with meta-analysis of 1,010 cases. Urol Oncol. 2016 Jun 3.

38. Kadian YS, Verma A, Rattan KN, Kajal P. Vitellointestinal Duct Anomalies in Infancy. J Neonatal Surg. 2016 Jul-Sep;5(3):30. 39. Marshall AS, Jayapal SS, Whitburn JA, Akinbiyi BA, Willetts IE. Recognising serious umbilical cord anomalies. BMJ Case Rep. 2013;2013.