Fetal magnetic resonance imaging contributes to the diagnosis and treatment of meconium peritonitis.

BACKGROUND: Meconium peritonitis (MP) is a rare fetal disease that needs to be urgently identified for surgical intervention. We report a series of 35 patients diagnosed prenatally with MP by magnetic resonance imaging (MRI), illustrate the imaging findings and investigate the predictive value of these findings for postpartum management. METHOD: A consecutive cohort of patients diagnosed with MP who were born at our institution from 2013 to 2018 was enrolled retrospectively. The prenatal ultrasound and MRI findings were analyzed. Fisher's exact probability test was used to evaluate the predictive value of MRI for surgical intervention between the operative group and the nonoperative group. RESULTS: Ascites (30/35) and distended bowel loops (27/35) were two of the most common prenatal MP-related findings on fetal MRI. Of the 35 infants, 26 received surgical intervention. All fetuses with MRI scans showing bowel dilatation (14/26, p = 0.048) and micro-colorectum (13/26, p = 0.013) required surgery. There were no significant differences in the number of fetuses with meconium pseudocysts and peritoneal calcifications between the two groups. CONCLUSION: Fetuses with bowel dilatation and micro-colorectum on MRI may need postpartum surgical intervention. Infants with only a small amount of ascites and slight bowel distention were likely to receive conservative treatment.

Decreased rectal meconium signal on MRI in fetuses with open spinal dysraphism.

OBJECTIVE: To evaluate rectal meconium signal in fetuses with open spinal dysraphism and correlate findings with postnatal exam. METHODS: This is a single-institution Institutional Review Board-approved Health Insurance Portability and Accountability Act (HIPAA) compliant retrospective analysis of fetal MRIs of open spinal dysraphism from 2004 to 2016. Fetuses with diagnostic T1-weighted images and postnatal follow-up at our institution were included. RESULTS: A total of 115 fetuses (average gestational age 23.9 ± 3.6 weeks) met inclusion criteria. Of these, 80% (92/115) had T1 hyperintense rectal meconium signal. Average height of the meconium column, measured from the base of the bladder to its most inferior extent, was 9.2 ± 4.3 mm in fetuses ≥20-week gestational age and 11.1 ± 4.4 mm in fetuses ≥23-week gestational age (n = 110) . None had bowel dilation. One of 115 fetuses had a simple form of anorectal malformation allowing complete repair in the neonatal period, but this fetus had a normal meconium column height on fetal MRI of 22 mm. The remaining 23/115 fetuses with lack of normal rectal meconium signal were born without evidence of anorectal malformation. CONCLUSION: Decreased or absent T1-hyperintense rectal meconium signal in fetuses with open spinal dysraphism does not correlate with imperforate anus postnatal and may be a reflection of neurogenic bowel in this patient population.

Meconium peritonitis: the role of postnatal radiographic and sonographic findings in predicting the need for surgery.

BACKGROUND: The role of imaging in meconium peritonitis is not limited to establishing a diagnosis; rather, it might also be helpful in determining which neonates require surgery. However, few data in the literature correlate the postnatal radiographic and sonographic findings with the need for surgery. OBJECTIVE: To compare the role of postnatal radiographic and sonographic findings in predicting the need for surgery in neonates with meconium peritonitis. MATERIALS AND METHODS: We conducted a retrospective analysis of clinical, imaging and surgical findings in all neonates with meconium peritonitis in the period 1999-2014. We divided the children into operative or non-operative groups and then correlated each group with the presence or absence of the following findings on both the radiographs and sonograms: peritoneal calcification, meconium pseudocyst, intestinal obstruction, volvulus, ascites and pneumoperitoneum. RESULTS: Thirty-seven neonates (22 males, 15 females) had meconium peritonitis in this period, of whom 23 (62%) required surgery and 14 (38%) were successfully treated non-surgically. None had an antenatal infection and three had cystic fibrosis (8%). Bowel obstruction identified on radiography (12/23, P=0.01) and sonography (9/23, P=0.04) and ascites identified with sonography (7/23, P=0.01) were associated with the need for surgical intervention. The presence of pneumoperitoneum and volvulus were also associated with surgical intervention. There was no significant statistical difference in the number of neonates with diffuse peritoneal calcification who were treated operatively or non-operatively. Four (33%) of the 12 neonates with meconium pseudocysts were successfully treated non-operatively. CONCLUSION: Imaging findings that predicted the need for surgery were intestinal obstruction, ascites, volvulus and pneumoperitoneum. Neonates with meconium pseudocysts did not require surgery if they were not associated with the described findings. The findings in our patients also indicate that those with diffuse peritoneal calcification as an isolated finding can be successfully treated non-operatively.

Using prenatal MRI to define features of meconium peritonitis: an overall outcome.

AIM: To use prenatal magnetic resonance imaging (MRI) to define features of meconium peritonitis (MP) and analyse the relationship between prenatal MRI findings and postnatal outcomes. MATERIALS AND METHODS: Eight cases were enrolled who had been diagnosed with MP through prenatal MRI; the diagnoses were confirmed at surgery and pathology or follow-up. MP was diagnosed by the findings of meconium ascites, meconium pseudocyst, or dilated bowel loops. Prenatal follow-up after diagnosis by MRI was performed by ultrasound. RESULTS: Prenatal MRI findings included massive meconium ascites (five out of eight cases), a small meconium pseudocyst (one out of eight), a large meconium pseudocyst along with a dilated bowel loop (one out of eight), a dilated bowel loop alone (one out of eight), and micro-colorectum (six out of eight). Six fetuses showed abdominal distension, bilious vomiting, and no normal meconium at birth; they underwent exploratory laparotomies and subsequently, survived and prospered. Only one fetus (with a small meconium pseudocyst) received conservative treatment. There was one mortality, and the cause of death was full-bowel necrosis. CONCLUSION: Prenatal MRI may be helpful for diagnosing MP, in cases where the specific MRI findings are persistent meconium ascites, a dilated bowel loop, micro-colorectum, and meconium pseudocyst. In particular, a micro-colorectum might indirectly reflect ileum atresia, which requires postnatal surgery.

Prenatal diagnosis of enterolithiasis at 18 weeks: multiple foci of intraluminal calcified meconium within echogenic bowel.

Enterolithiasis is an uncommon finding of a dilated hyperechogenic bowel with multiple ball-like echogenic structures at a routine prenatal check-up using ultrasonography. We here report a case of prenatally diagnosed enterolithiasis at 18 weeks of gestation, showing multiple hyperechogenic foci rolling within the bowel fluid after peristalsis. The size of the dilated bowel gradually increased during pregnancy. Magnetic resonance image demonstrated the dilated lower bowel with blind-ending rectum. A postnatal contrast medium study with retrograde urethrography revealed a middle imperforate anus and a rectourethral fistula. A careful examination, even before 20 weeks of gestation, is extremely useful in demonstrating intraluminal coarse calcifications within an echogenic bowel.

Ultrasound-guided contrast enema for meconium obstruction in very low birth weight infants: Factors that affect treatment success.

INTRODUCTION: This study aimed to assess the therapeutic results of ultrasound (US)-guided water-soluble contrast enema in very low birth weight (VLBW) preterm infants (<1,500 g) with meconium obstruction and to study factors that affect therapeutic results. METHODS: This study included a total of 33 consecutive VLBW infants with clinically diagnosed meconium obstruction underwent US-guided water-soluble contrast enema, from April 2007 to March 2014. Patients were classified into two groups based on to procedure outcome: the success group (evacuation of the meconium plug resolution followed by improved bowel distention within 2 days of the procedure, without additional interventions), and the failure group (the contrast enema failed to relieve the obstruction, or other procedure-related complications occurred). Patient- and mother-related clinical factors and procedure-related factors were compared between both groups. RESULTS: Overall success rate was 54.5%, with 18 successful (M:F=10:8), and 15 failure (M:F=7:8) cases. When compared with the failure group, the success group patients showed statistically significant older gestational age (29(+1) vs. 27 weeks; p=0.028), larger birth weight (1023.1g vs. 790.3g; p=0.048), and higher body weight on the day of the procedure (1036.2g vs. 801.6g, p=0.049). However, no statistically significant differences were seen between other patient and maternal factors. Among the procedure-related factors, retrial of contrast injection during the procedure was associated with significantly higher success than the single trial (p=0.027). The presence of refluxed contrast into the distal ileum was the statistically significant predictor for success of the procedure (p=0.038). There were three cases of bowel perforation (9.1% per person). CONCLUSION: US-guided water-soluble contrast enema in VLBW infants with meconium obstruction showed a 54.5% success rate and a 9.1% perforation rate per person. Among the procedure-related factors, retrial of contrast injection during the procedure and the presence of refluxed contrast into the distal ileum were related to the success of the procedure.

Antenatal sonographic features of ileal atresia.

AIM: The purpose of this study was to determine the antenatal sonographic features of ileal atresia. MATERIAL AND METHODS: We identified neonates with surgically-confirmed ileal atresia who had antenatal sonography performed in our institution between 1 January 1999 and 30 June 2009. The antenatal sonography images and reports were reviewed. RESULTS: Sixteen neonates had surgically-confirmed ileal atresia in our institution in 11 years. Seven fetuses (43.7%) did not have any intestinal abnormalities detected antenatally on ultrasonography. Nine fetuses (56.3%) had various sonographic features of ileal atresia, including multiple dilated bowel loops, ascites, cysts, and polyhydramnios with or without associated anomalies. Six of nine fetuses had multiple dilated bowel loops and two fetuses had ascites. One fetus had a large, cystic, mixed, echogenic dilatation of bowel. Polyhydramnios was present in three fetuses. Heart anomalies, kidney anomalies, or hydrops were present in four fetuses. Eight of 16 fetuses (50%) had other intestinal problems, including intussusceptions in one fetus, small bowel malrotation, meconium pseudocyst volvulus, meconium peritonitis, and a congenital band. CONCLUSION: The prenatal sonographic features of ileal atresia are not simple. Various sonographic findings are shown and ileal atresia was detected in about 60% of cases.

[Fetal meconium pseudocyst secondary to in utero perforation of colon transversum and meconium peritonitis].

Fetal bowel intrauterine perforation causes sterile inflammation of the peritoneum, known as meconium peritonitis. In some cases the perforation closes spontaneously, thus forming a meconium pseudocyst between the intestinal loops and the omentum. Meconium peritonitis, complicated by pseudocyst formation, should always be considered when a fetal abdominal mass with diverse echogenicity and hyperechogenic calcifications is observed on prenatal ultrasound. Usually, this is associated with ascites and/or polyhydramnios. The differential diagnosis necessitates exclusion of all other fetal abdominal tumors. We present a case report of meconium pseudocyst diagnosed prenatally at 32 weeks of gestation which was successfully treated by surgery after birth.

Evolution of sonographic findings in a fetus with ileal atresia.

We report a case of a meconium pseudocyst secondary to ileal atresia and midgut volvulus. Initially, a single anechoic cyst was detected on prenatal sonography. The cyst gradually increased in size during the second trimester and eventually appeared as a large mass in the lower abdomen with echogenic content and associated with bowel dilatation. This case indicates that until the mid third trimester a single sonolucent cyst without signs of bowel obstruction may be associated with congenital intestinal obstruction.

Meconium peritonitis presenting as abdominal calcification: three cases with different pathology.

Intra-abdominal calcification is uncommon in newborns and has several causes of which meconium peritonitis is the most frequent. Three neonates with intra-abdominal calcification as a complication of meconium peritonitis are presented. The types of meconium peritonitis were cystic, meconium pseudocyst and meconium ascites. Two required surgical intervention. Meconium peritonitis should be considered in newborns with intra-abdominal calcification.

Diminishing role of contrast enema in simple meconium ileus.

PURPOSE: Contrast enema is the initial study of choice for simple meconium ileus to confirm diagnosis and to relieve obstruction. Despite favorable historically published results, our clinical impression suggests decreased effectiveness of the contrast enema resulting in more surgical interventions in contemporary practice. METHODS: A retrospective multiinstitutional review for a 12-year period was conducted for neonates diagnosed with meconium ileus by contrast enema. The neonates were divided into 2 groups-historic group (HG = before 2002) and contemporary group (CG = after 2002). T test was used for comparison of continuous variables and chi(2) for categorical data. RESULTS: Thirty-seven total patients were identified (21 females and 16 males). Obstruction was relieved in 8 neonates (22% overall success rate). Average enema attempt per patient was decreased in the CG group compared to HG (1.4 vs 1.9). The success rate in the CG group was 5.5% (1/18) compared to 39% (7/18) in HG. CONCLUSIONS: In this review, success of contrast enema for relief of meconium ileus has significantly decreased over time. These findings may be because of reluctance to repeat enemas, change in radiologist experience, or use of contrast agent. As a result, higher rates of operative intervention are now observed. In stable patients, surgeons should recommend repeat enemas before exploration.

Meconium periorchitis: intrauterine diagnosis and neonatal outcome: case reports and review of the literature.

Meconium periorchitis (MP) is a rare disorder caused by fetal meconium peritonitis with subsequent spillage of meconium into the scrotal sac. The condition is seldom diagnosed correctly during fetal life and the ultrasonographic diagnoses reported vary from no diagnosis to hematoma or hydrocele. It is usually diagnosed clinically during the first year of life when a scrotal mass is an incidental finding. Here, we describe two cases of MP that were diagnosed during routine intrauterine ultrasound examination for fetal growth assessment, and confirmed after birth. One infant underwent a surgical excision of the scrotal mass, confirming the histological diagnosis of meconium periorchitis. The other was managed conservatively. Neither had cystic fibrosis. Thus, we believe that a diagnosis of MP should be considered when prenatal ultrasonographic findings are suspicious for the problem. The awareness of the ultrasonographer and the neonatologist are important for immediate postnatal management, as congenital scrotal masses may have other etiologies.

Generalized arterial calcification of infancy associated with meconium peritonitis: a case report and review of the literature.

Generalized arterial calcification of infancy (GACI) is a rare genetic disorder consisting of diffuse arterial calcification and intimal proliferation. The disease typically results in progressive arterial stenosis and frequently leads to death from myocardial ischemia by 6 months of life. Affected infants are usually diagnosed before birth or in the neonatal period with symptoms of congestive heart failure. Therapy with bisphosphonate has been used to treat the condition, but with inconsistent results. The disease is associated with mutations in ENPP1 in the majority of the cases. Here we report a unique case of GACI associated with in utero meconium peritonitis and without coding region mutations of the ENPP1 gene. GACI should be considered in the differential diagnosis in infants presenting with arterial calcifications and congenital anomalies of the gastrointestinal tract.

Meconium per vagina: a rare presentation of meconium peritonitis.

Meconium peritonitis results from antenatal perforation of the gastrointestinal tract; it presents as gastrointestinal obstruction, intraabdominal masses, or calcification. The presentation with passage of meconium per vagina secondary to meconium peritonitis is rare. We describe the radiologic and surgical findings in a neonate who had passage of meconium per vagina secondary to ileal atresia and meconium peritonitis. Initial clinical and radiologic examination suggested rectal atresia with an associated rectovaginal fistula, although subsequently, this was not the case. Possible explanations for the passage of meconium per vagina include decompression of a meconium cyst via the left fallopian tube or direct perforation of a collection into the vagina from the peritoneal cavity.

Fetal enterolithiasis: prenatal sonographic and MRI diagnosis in two cases of urorectal septum malformation (URSM) sequence.

OBJECTIVES: Enterolithiasis (multiple calcifications of intraluminal meconium) is a rare, prenatal ultrasonographic finding. In this study, our aim was to evaluate the prenatal diagnostic features and discuss the management of the patients. METHODS: The data of two cases of prenatally diagnosed fetal enterolithiasis were collected from ultrasound scan, magnetic resonance imaging (MRI) and neonatal or postnatal autopsy records. The findings were evaluated in both prenatal and postnatal periods. Chromosomal analysis was performed in one case. An evaluation of primary and secondary malformations was done. Coexisting anomalies were searched for via radiology, neonatal surgery and histopathology. RESULTS: Malformations in two cases (both males) with partial and complete urorectal septum malformation (URSM) sequence were described. The absence of an anal opening and presence of a fistula between the urinary and gastrointestinal tract were common findings. These features were considered as primary malformations contributing to the formation of enterolithiasis. Secondary anomalies (urinary and gastrointestinal system malformations, pulmonary hypoplasia, genital and other coexisting anomalies) were evaluated. CONCLUSIONS: The prenatal detection of enterolithiasis carries a poor prognosis. Most of the previously reported cases were invariably associated with major fetal malformations of the urinary and gastrointestinal tract. It is a warning sign for large bowel obstruction with or without enterourinary fistula. Therefore, adequate gastrointestinal and urologic studies must be undertaken after birth for the final diagnosis. There is a high mortality rate in the reported cases, mostly attributed to associated anomalies, and all survivors required neonatal surgery. It is important to differentiate the partial from the full URSM sequence because the prognosis in the partial URSM sequence is generally good, with long-term survival being common.

Neonatal intestinal obstruction simulating meconium ileus in infants with long-segment intestinal aganglionosis: radiographic findings that prompt the need for rectal biopsy.

BACKGROUND: The initial clinical presentation and radiographic finding of microcolon in children with long-segment intestinal aganglionosis involving the entire colon, ileum and sometimes the jejunum can mimic meconium ileus. This makes the diagnosis difficult for the radiologist and surgeon. OBJECTIVE: To document and describe the clinical and radiographic findings in children with long-segment intestinal aganglionosis who are initially thought to have meconium ileus. MATERIALS AND METHODS: We reviewed the cases of six neonates with long-segment intestinal aganglionosis presenting as meconium ileus at our institutions between 1978 and 2002. We examined the clinical presentation and the radiographic, surgical, and pathologic findings. In addition, 17 cases from the literature were identified and are included in the discussion. RESULTS: A total of 23 cases were reviewed. Right lower quadrant intraluminal calcifications were noted on abdominal radiographs in all six neonates of our series and were described in 13 of the 17 neonates reported in the literature. Similarly, a microcolon was present in five of the six neonates of our series and in 14 of 16 historical neonates (one not reported). CONCLUSION: In a neonate with small-bowel obstruction and a microcolon, the presence of right lower quadrant intraluminal calcifications should raise the suspicion of long-segment intestinal aganglionosis even if the operative findings are typical of meconium ileus and a biopsy should be performed.

Contrast enema depiction of small-bowel volvulus in complicated neonatal bowel obstruction.

About one-half of patients with meconium ileus (MI) present with a complication such as volvulus, atresia, meconium peritonitis or giant cystic meconium peritonitis. The treatment of these complications requires surgery. However, the preoperative diagnosis of complicated MI is difficult. We describe two neonates with complicated small-bowel obstruction, one with MI related to cystic fibrosis and the other not related to cystic fibrosis. In both, contrast enema depicted a spiral appearance of the distal small bowel, which at surgery proved to be the result of volvulus associated with antenatal bowel perforation. This appearance of the small bowel on contrast enema in this clinical setting has not been previously described. The recognition of this spiral appearance of the distal small bowel suggests the need for surgery.

[Management of meconium peritonitis: a remarkable case of idiopathic meconium peritonitis diagnosed antenatally]. / Prise en charge de la péritonite méconiale: à propos d'un cas singulier de péritonite méconiale idiopathique à révélation anténatale.

Meconium peritonitis is an inflammatory peritonitis induced by meconium extruding into the peritoneal cavity through a perforation of the fetal intestine. Antenatal diagnosis is possible. Prognosis depends on the pathology having caused perforation. This is often unknown. The objectives of this article are to analyze the contribution of antenatal investigations to estimating neonatal prognosis of meconium peritonitis, and to define optimal management. We describe a case of meconium peritonitis diagnosed in utero with particularly severe ultrasound presentation suggesting a potentially lethal course for the neonate. An eutrophic infant was delivered vaginally after preliminary aspiration of the meconium ascites. The neonate presented with a very distended abdomen and responded well to neonatal resuscitation. Laparotomy exploration confirmed the diagnosis of meconium peritonitis. No cause was identified. No obvious perforation was found. The postsurgery period was uneventful. At later follow-up the infant was doing well, free of further problems notably of any digestive disorder. Antenatal ultrasound features suggestive of severe meconium peritonitis are distended fetal bowel loops, huge cystic masses, major meconium ascites, and polyhydramnios. These neonates have a high risk of obstruction and intestinal perforation. Intestinal resection is frequently required. Cardiopulmonary resuscitation is necessary more often in these neonates with a higher risk of fatal outcome due to respiratory distress syndrome or surgery complications. Prognosis remains good after antenatal diagnosis for neonates free of cystic fibrosis, providing delivery takes place in a center with adequate technical facilities.