Meconium peritonitis (MP) is a rare condition that results from the development of bowel obstruction in a growing fetus within the uterus. This may lead to perforation of the gut wall, which in turn leads to a leakage of meconium into the peritoneal cavity. Aseptic peritonitis ensues, due to a secondary inflammatory response. The outcome of MP depends to some extent on diagnostic and management approaches, which have greatly improved over the years [1] [2]. Severity and symptomatology of the condition are determined by the gestational age of the fetus, at the time the perforation occurs.

There are many possible causes of bowel obstruction in utero. These range from vascular factors such as mesenteric ischemia, to bowel pathologies such as meconium ileus, intussusception, volvulus, intestinal atresia, Hirschsprung's disease, hernias, and meconium plugs [3]. In addition to these, congenital infections, particularly parvovirus B19, rubella and cytomegalovirus, have been shown to be predisposing factors in the occurrence of MP [4]. There is an established association between MP and cystic fibrosis [5]. Polyhydramnios, jejunoileal atresia, and other gastrointestinal malformations have also been linked to MP.

There are three main classes of MP, the first being fibro-adhesive. This results in calcification and tissue deposition on the area of perforation, producing a mass that seals the defect. Most perforations are closed off before birth. The other types of MP are cystic and generalized. Additional effects of the inflammatory changes that may occur include ascites, fibrosis and intraperitoneal meconium calcifications.

• Inflammation

  In five patients who underwent drainage of cysts after birth, systemic inflammation could not be completely suppressed before curative surgery. [ncbi.nlm.nih.gov]

• Sepsis

  Postnatal follow-up revealed all but 2 (died of sepsis and prematurity, respectively) doing well. [ncbi.nlm.nih.gov]

  Sepsis workup and stool cultures were sent which were sterile. Feeds were changed initially to lactose free formula and later even to elementary formula. [sciencerepository.org]

  However, we chose to bring out a stoma at delayed laparotomy given their patient’s prolonged neonatal intensive care unity stay and sepsis course. [jmedicalcasereports.biomedcentral.com]

• Neonatal Intestinal Obstruction

  Another rare cause of neonatal intestinal obstruction is the megacystis-microcolon-intestinal hypoperistalsis syndrome.22 In this disorder, the small bowel is dilated and shortened, and the colon is a microcolon (Figure 7). [aafp.org]

  Failure to pass meconium: diagnosing neonatal intestinal obstruction. Loening-Baucke V. Am Fam Physician. Nov 1999; 60(7): 2043-2050. 2. Bilious vomiting in the newborn: rapid diagnosis of intestinal obstruction. Kimura K. Am Fam Physician. [pedclerk.bsd.uchicago.edu]

  The water-soluble enema will also exclude other causes of neonatal intestinal obstruction. [clinicalgate.com]

  Noblett’s criteria for nonoperative gastrografin enema therapy [30]: Other causes of neonatal distal intestinal obstruction must first be excluded. [intechopen.com]

  J Radiol 84:1986–1988 PubMed CAS Google Scholar Loening-Baucke V, Kimura K (1999) Failure to pass meconium: diagnosing neonatal intestinal obstruction. [link.springer.com]

• Splenectomy

  Hone and expand your surgical skills by watching videos of minimally invasive procedures for recto urethral fistula, biliary atresia, laparoscopic splenectomy, uterine horn, and more. [books.google.com]

• Intestinal Perforation

  Postnatal contrast CT scan is required to define persistent intestinal perforation invisible with prenatal USS. Copyright 2005 John Wiley & Sons, Ltd. [ncbi.nlm.nih.gov]

  Intrauterine intestinal perforation may result from various causes. Patients with MP are divided into those with and without associated intestinal obstruction. [taylorfrancis.com]

• Intestinal Atresia

  The main causes were intestinal atresia and idiopathic bowel perforation. The mortality rate was 2.4%, and the morbidity rate was 34.1%. CONCLUSIONS: Good survival rate was achieved. But there was rather high morbidity. [ncbi.nlm.nih.gov]

• Bilious Vomiting

  Six fetuses showed abdominal distension, bilious vomiting, and no normal meconium at birth; they underwent exploratory laparotomies and subsequently, survived and prospered. [ncbi.nlm.nih.gov]

  In 80% of cases the papilla of Vater opens into the proximal duodenum causing the vomiting to be bilious. [www3.health.vic.gov.au]

  vomiting, and failure to pass meconium.Thickened bowel loops filled with rubbery meconium areoften visible and palpable through the abdominal wall.Remarkable abdominal distention, abdominal tenderness,or abdominal erythema indicates perforation.Meconium [patientcareonline.com]

  Hirschprung’s disease Small left colon syndrome Imperforate anus Failure to pass meconium with non-bilious vomiting Duodenal atresia proximal to ampulla of Vater Annular pancreas Initial passage of meconium with subsequent obstruction and non-bilious [pedclerk.bsd.uchicago.edu]

  vomiting Imaging Findings On conventional radiographs Meconium, being fluid density, is normally invisible on radiographs In meconium ileus, there may be dilated loops of bowel (small bowel) typically without air-fluid levels because of the viscosity [learningradiology.com]

• Heart Disease

  Moss' heart disease in infants, children, and adolescents, 4th ed. Baltimore: Williams & Wilkins, 1989:530. ‏ [books.google.com]

• Cesarean Section

  At 35 weeks gestation, a cesarean section was performed for obstetric reasons. As a consequence of a prenatal bowel perforation, the neonate developed meconium peritonitis, for which she needed laparotomy. [ncbi.nlm.nih.gov]

The diagnosis of meconium peritonitis can be made either in utero or after birth. Some features of the disease can spontaneously resolve before birth. It may be beneficial to test for cystic fibrosis, as there is a strong correlation between the two conditions.

During the prenatal period, imaging techniques are used to assess the fetal abdomen. These are:

• Ultrasound: A snowstorm appearance of the abdomen may be visualized, as well as focal calcifications that appear hyperechoic [6]. Some of the other likely findings on ultrasound examination are fetal ascites, wide abdominal circumference and polyhydramnios [7]. Distended bowel loops may also be present. The use of ultrasound may be instrumental in predicting the overall outcome of the newborn. Furthermore, information gained from imaging can predict the likelihood of surgery during the neonatal period. Some literature classifies ultrasound findings in MP into types I to III, which correspond to: massive ascites, giant pseudocysts and small pseudocysts or calcifications [8] [9]. Types I and II were shown to be predictive of poor outcomes in the neonatal period. In addition, if such features persist, surgery is usually required in the postnatal period [10].
• Xray: This may show peritoneal or scrotal calcifications (in cases of a patent processus vaginalis), and an intraabdominal mass, which is often a meconium pseudocyst.

Surgical treatment and management of meconium peritonitis depend on the clinical presentation of the newborn. [ncbi.nlm.nih.gov]

Then, we retraced the treatments, pathological reports and outcomes of the fetuses with MP. [bmcmedimaging.biomedcentral.com]

Establishing clear postnatal treatment and prognosis is difficult because of the heterogeneity of the results obtained by ultrasound. [ncbi.nlm.nih.gov]

Prognosis: In case of simple peritonitis the outcome is good and surgical intervention is not necessary. In case of complex peritonitis (associated with bowel dilatation, ascites) the prognosis is poor and neonatal mortality is >50%. [fetalmedicine.org]

In addition, depending upon the etiology, ascites, polyhydramnios or fetal bowel distention may be present. [fetalsono.com]

The purpose of this article is to review a case of meconium peritonitis while considering its etiology, diagnosis, management, and multidisciplinary team care. [ncbi.nlm.nih.gov]

The diagnosis can be made with ultrasound or by abdominal x‐ray, with varied images, altering according to the etiology of the obstruction/perforation. [sma.org]

Etiology fetal intestinal perforation Cystic fibrosis digestive cystic fibrosis fetal intestinal tumors jejunal congenital fibrosarcoma ( 12776248 ) Complications disseminated intravascular meconium meconium per vagina References Meconium peritonitis [humpath.com]

A retrospective epidemiologic study of pediatric fibrosarcomas. J Pediatr Surg. 1978; 13 735-738 9 Plaschkes J. Epidemiology of neonatal tumours. Puri P Neonatal Tumours. [thieme-connect.com]

The epidemiology of tracheo-oesophageal fistula and oesophageal atresia in Europe: EUROCAT Working Group. Arch Dis Child 1993;68:743-8. [ PUBMED ] 3. Spitz L. Esophageal atresia: Lessons I have learned in a 40-year experience. [afrjpaedsurg.org]

The pathophysiologic progression of this condition is demonstrated by serial ultrasound examinations. Neonatal radiologic confirmation of the diagnosis is also presented. [ncbi.nlm.nih.gov]

Newborn Surgery, Third Edition provides a comprehensive compendium of the pathophysiology, investigation and management of neonatal disorders. [books.google.com]

A review of pathophysiology and management of foetuses and neonates with meconium ileus for the pediatric surgeon. Journal of Pediatric Surgery. 2012;47:772-781 2. Copeland DR, St Peter SD, Sharp S, et al. [intechopen.com]

Etiology and pathophysiology poorly understood Most commonly presents 10-12 days after birth, often accompanied by bloody stools and abdominal distension Pneumatosis interstitialis is pathognomonic Coronal reformatted MDCT image showing extensive pneumatosis [pedclerk.bsd.uchicago.edu]

MI) rather than pulmonary complaints.4 However, there is no evidence of distinct allelic frequencies or haplotypic variants in CF patients with MI compared with those without22 or in CF patients with significant liver disease.23,24 Gastrointestinal Pathophysiology [clinicalgate.com]

After constructing a diversion colostomy, a cutaneous vesicostomy was necessary to prevent recurrent urinary tract infections. [ncbi.nlm.nih.gov]

1. Nam SH, Kim SC, Kim DY, et al. Experience with meconium peritonitis. J Pediatr Surg. 2007 Nov;42(11):1822-1825.
2. Kuroda T, Kitano Y, Honna T, Sago H, Hayashi S, Saeki M. Prenatal diagnosis and management of abdominal diseases in pediatric surgery. J Pediatr Surg. 2004;39(12):1819-1822.
3. Chan KL, Tang MH, Tse HY, Tang RY, Tam PK. Meconium peritonitis: Prenatal diagnosis, postnatal management and outcome. Prenat Diagn. 2005;25(8):676-682.
4. Schild RL, Plath H, Thomas P, Schulte-Wissermann H, Eis-Hubinger AM, Hansmann M. Fetal parvovirus B19 infection and meconium peritonitis. Fetal Diagn Ther. 1998;13(1):15-18.
5. Hamada T, Hirose R, Kosaka T, et al. Giant cystic meconium peritonitis associated with a cloacal anomaly: Case report. J Pediatr Surg. 2008;43(3):E21-23.
6. Berrocal T, Lamas M, Gutieérrez J et-al. Congenital anomalies of the small intestine, colon, and rectum. Radiographics. 1999;19(5):1219-1236.
7. Mcnamara A, Levine D. Intraabdominal fetal echogenic masses: a practical guide to diagnosis and management. Radiographics. 2005;25(3):633-645.
8. Kamata S, Nose K, Ishikawa S, et al. Meconium peritonitis in utero. Pediatr Surg Int. 2000;16(5-6):377-379.
9. Zangheri G, Andreani M, Ciriello E, Urban G, Incerti M, Vergani P. Fetal intra-abdominal calcifications from meconium peritonitis: sonographic predictors of postnatal surgery. Prenat Diagn. 2007;27(10):960-963.
10. Shyu MK, Shih JC, Lee CN, Hwa HL, Chow SN, Hsieh FJ. Correlation of prenatal ultrasound and postnatal outcome in meconium peritonitis. Fetal Diagn Ther. 2003;18(4):255-261.