The natural history of meconium peritonitis diagnosed in utero

Fetal Meconium Peritonitis - Prenatal Findings and Postnatal Outcome: A Case Series, Systematic Review, and Meta-Analysis

PURPOSE

 To describe the postnatal outcome of fetal meconium peritonitis and identify prenatal predictors of neonatal surgery.

METHODS

 We retrospectively reviewed all fetuses with ultrasound findings suspicious for meconium peritonitis at a single center over a 10-year period. A systematic review and meta-analysis were then performed pooling our results with previous studies assessing prenatally diagnosed meconium peritonitis and postnatal outcome. Prenatal sonographic findings were analyzed to identify predictors for postnatal surgery.

RESULTS

 34 cases suggestive of meconium peritonitis were diagnosed at our center. These were pooled with cases from 14 other studies yielding a total of 244 cases. Postnatal abdominal surgery was required in two thirds of case (66.5 %). The strongest predictor of neonatal surgery was meconium pseudocyst (OR [95 % CI] 6.75 [2.53-18.01]), followed by bowel dilation (OR [95 % CI] 4.17 [1.93-9.05]) and ascites (OR [95 % CI] 2.57 [1.07-5.24]). The most common cause of intestinal perforation and meconium peritonitis, found in 52.2 % of the cases, was small bowel atresia. Cystic fibrosis was diagnosed in 9.8 % of cases. Short-term neonatal outcomes were favorable, with a post-operative mortality rate of 8.1 % and a survival rate of 100 % in neonates not requiring surgery.

CONCLUSION

 Meconium pseudocysts, bowel dilation, and ascites are prenatal predictors of neonatal surgery in cases of meconium peritonitis. Fetuses with these findings should be delivered in centers with pediatric surgery services. Though the prognosis is favorable, cystic fibrosis complicates postnatal outcomes.

The significance of internal calcifications on perinatal post-mortem radiographs

AIM

To determine whether the presence of internal calcifications on perinatal post-mortem skeletal surveys (PMSS) are associated with certain diagnoses of fetal loss.

METHODS AND MATERIALS

A 6-month retrospective, single-centre, cohort study was conducted on PMSS performed for perinatal death assessment. One reader re-reviewed all PMSS images for the presence and location of internal calcifications, and noted whether these were included within the original radiology report. Findings at autopsy were then reviewed independently by a second researcher and cause of fetal loss or main diagnosis recorded. Chi-squared tests were conducted to identify differences between those with and without internal calcifications at PMSS.

RESULTS

Two hundred and thirty perinatal deaths (mean gestational age 18 weeks; average 12–35 weeks) were included in the study, of which 42 (18.3%) demonstrated intra-abdominal calcifications, and 16/42 (38.1%) were mentioned in the radiology reports. Most calcifications were found to be within the lumen of the gastrointestinal tract, and in the left upper quadrant of the abdomen. There was no statistical difference between identifiable causes for fetal loss at autopsy in cases with and without calcification at PMSS (59.5% versus 58.5% respectively, p=0.904). Nevertheless, where calcification and a cause for fetal loss were found, the aetiology was more likely to be due a fetal rather than placental issue.

CONCLUSION

The presence of internal calcifications on PMSS was not associated with an increased likelihood of explainable fetal loss or particular diagnosis at autopsy.

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Fetal calcifications on post-mortem skeletal surveys are not significantly associated with causes of fetal loss.

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When present, internal calcifications were usually seen in lower gestational aged fetuses, intra-abdominal in location, with the majority being intraluminal.

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The majority of radiologists do not report internal fetal calcifications on radiographs, without significant consequences for final outcome at autopsy.

Omental calcification, necrotizing enterocolitis, and undescended testes after fetal abdomino-amniotic shunting performed for the management of meconium peritonitis: A case report

Prenatal ultrasonography (US) in a 39 year-old woman revealed massive fetal ascites. A fetal abdomino-amniotic shunting procedure was performed. Subsequently, plain radiographs demonstrated diffuse gaseous distention of the bowel and multiple punctate calcifications in the left upper abdomen. Postnatal US examination showed multiple echogenic foci in the liver and the left upper abdomen, bowel wall thickening in the right-sided abdomen, and undescended testes. There was no intra-abdominal free air or loculated fluid collections. Medical management was instituted secondary to the clinical suspicion of omental calcification, necrotizing enterocolitis, and undescended testes. Follow-up US examination showed resolution of portal vein gas and bowel wall thickening. The neonate recovered fully.

Imaging of the pediatric peritoneum, mesentery and omentum

The normal peritoneal structures, including the mesenteries and the omenta, are only a few cell layers thick and are visible on imaging based upon the tissues (e.g., fat) and structures (e.g., blood vessels and lymph nodes) contained within them. These structures become more visible and change in appearance when involved by pathological processes. In this pictorial essay, we discuss the normal anatomy of the various abdominopelvic peritoneal structures and illustrate numerous developmental and acquired diagnoses that involve these structures in the pediatric and young adult population.

Prenatal Imaging of the Gastrointestinal Tract with Postnatal Imaging Correlation

Prenatal detection of a wide variety of anomalies and masses of the gastrointestinal tract is now possible. Prenatal imaging with ultrasonography and in selected cases magnetic resonance imaging provides invaluable information to the referring obstetrician, the maternal fetal medicine specialist, the neonatologist and pediatrician who will care for the child after birth, the surgeons and pediatric specialists who will repair or manage a prenatally detected anomaly, and of course to the parents, allowing them to prepare psychologically and financially for the specific interventions that may be needed for their child. Additional screening for associated anomalies can take place, route of delivery can be decided, and arrangements for delivery in an appropriate setting can be made. Prenatal detection also allows for consideration for pregnancy termination. This article will give a broad overview of anomalies of the gastrointestinal tract that can be detected prenatally and their imaging appearance postnatally.

Can we select fetuses with intra-abdominal calcification for delivery in neonatal surgical centres?

BACKGROUND

Prenatal ultrasound (US) diagnosis of fetal intra-abdominal calcification (iAC) is frequently caused by an in utero perforation causing meconium peritonitis. Our ability to predict which fetuses will require postnatal surgery is limited. The aim of our study is to correlate iAC and associated US findings with postnatal outcome.

METHODS

A single centre retrospective review of all cases of fetal iAC diagnosed between 2004 and 2010 was performed. Maternal demographics, fetal US findings, and outcomes (need for surgery and mortality) were collected. Descriptive and comparative statistical analyses were performed.

RESULTS

Twenty-three cases of iAC were identified. There were no cases of fetal demise or postnatal deaths. Three liveborns (13%) required abdominal surgery at a median of 2 days (0-3) for intestinal atresia. US findings of iAC and dilated bowel with (p=0.008) or without (p=0.005) polyhydramnios predicted a need for postnatal surgery as did the combination of iAC, polyhydramnios, and ascites (p=0.008). Conversely, iAC alone or associated with oligohydramnios, polyhydramnios, ascites, or growth restriction did not predict need for postnatal surgery.

CONCLUSION

The majority of fetuses with iAC on prenatal US do not require surgery. Associated US findings (bowel dilation) can be used to select fetuses for delivery in neonatal surgical centres.

US assessment of neonatal bowel (necrotizing enterocolitis excluded)

US plays a main role in evaluating neonatal gastrointestinal disorders. The authors describe the US appearance of normal neonatal bowel, midgut volvulus, small bowel atresia, meconium ileus, meconium peritonitis, different meconium plug syndromes, Hirschsprung disease, intestinal duplication cysts, some other abdominal cysts, some intraperitoneal infections, excluding necrotizing enterocolitis, and anorectal anomalies. The use of sonography in the imaging diagnostic strategies of these congenital and acquired anomalies is emphasized.

Pathophysiology, diagnosis, and management of pediatric ascites

The pediatric population has a number of unique considerations related to the diagnosis and treatment of ascites. This review summarizes the physiologic mechanisms for cirrhotic and noncirrhotic ascites and provides a comprehensive list of reported etiologies stratified by the patient's age. Characteristic findings on physical examination, diagnostic imaging, and abdominal paracentesis are also reviewed, with particular attention to those aspects that are unique to children. Medical and surgical treatments of ascites are discussed. Both prompt diagnosis and appropriate management of ascites are required to avoid associated morbidity and mortality.

Prenatal treatment of meconium peritonitis with urinary trypsin inhibitor

We describe a case of congenital meconium peritonitis with progressive fetal ascites and polyhydramnios. Fetal ascites could be only partially reduced on paracentesis at 29 weeks' gestation, and it subsequently increased. Urinary trypsin inhibitor (UTI), a physiological anti-inflammatory substance, was administered into the fetal abdominal cavity at a second paracentesis performed at 35 weeks' gestation. There was a significant amount of fetal ascites remaining 1 day after the second paracentesis, but this completely resolved within 5 days. A healthy infant was delivered vaginally and no surgical intervention was required. The case suggests that UTI can reduce meconium-induced chemical peritonitis and thereby facilitate intrauterine remission of fetal ascites.

A large meconium pseudocyst that developed into the generalized type during the antepartum period

A fetal intraabdominal cystic mass, measuring 6 cm, was detected at 30 weeks of gestation in a 27-year-old gravida 2 para 1 woman. At 33 weeks of gestation, the cyst disappeared. Ultrasonography showed fetal bowel dilatation, polyhydramnios, and intraabdominal calcifications. Fetal meconium peritonitis was diagnosed prenatally. Because the fetal ileus became worse, a cesarean section was performed at 35 weeks of gestation; a female infant weighing 2,131 g with an Apgar score of 8 was delivered. Six hours after birth, the neonate received an ileostomy. The bowel was reanastomosed 42 days after the initial operation. On postoperative pathology, a meconium pseudocyst was diagnosed. To our knowledge, this is the first report of a large fetal meconium pseudocyst that developed into the generalized type in the uterus during the preterm antepartum period.

A case of massive meconium peritonitis in utero successfully managed by planned cardiopulmonary resuscitation of the newborn

We report a case of emergent massive meconium peritonitis due to intrauterine volvulus without malrotation. Fetal ascites was detected on a regular ultrasonographic examination, and fetal distress was found on cardiotocographic monitoring. The mother had noticed a slight decrease in fetal movements over the preceding 24 hours. Prenatal magnetic resonance imaging allowed us to distinguish the meconium from fetal peritoneal fluid and to evaluate the degree of compression of the fetal thoracic cavity. The infant was delivered by emergency cesarean section and demonstrated tense abdominal ascites with edema at birth. She required cardiopulmonary resuscitation and immediate paracentesis.

Prenatal diagnosis and postnatal management of meconium peritonitis

BACKGROUND

Meconium peritonitis (MP) is a rare prenatal condition that leads to substantial neonatal morbidity and mortality.

PATIENTS AND METHODS

All patients between 1998 and 2006 referred for prenatal diagnosis were retrospectively analyzed for diagnosis of MP. Prenatal ultrasound findings were compared with postnatal etiology, intraoperative findings, and postnatal outcome of the patients.

RESULTS

Antenatal MP was diagnosed in 14 fetuses between 18 and 38 weeks' gestation. The prenatal diagnosis of MP was confirmed by clinical and radiological findings in 8 (62%) of 13 infants born alive. All patients were delivered preterm between 33 and 36 weeks' gestation by cesarean section. Urgent neonatal surgery for treatment of bowel obstruction was required in all eight infants. Prenatal ultrasound diagnosis of bowel dilatation was the only variable found to be associated with the need for subsequent surgical intervention (P=0.02).

CONCLUSIONS

Clinical outcome of MP diagnosed antenatally can be either mild or severe form. The underlying cause of severe MP is heterogeneous and neonatal surgery was always required.

Meconium pseudocyst: a classical and successfully treated case

Meconium peritonitis with pseudocyst formation is rare and can be lethal. We report a newborn infant with antenatal sonographic diagnosis of bowel dilatation and giant meconium pseudocyst. Postnatal presentation included a palpable abdominal mass and abdominal distention. Abdominal X-ray revealed a huge egg-shell calcified mass containing air-fluid level. Postnatal sonography revealed a cystic mass with air-fluid level and acoustic shadows. Computed tomography showed a giant communicating cyst with egg-shell calcification, which compressed the other intestinal loops to the posterior peritoneal cavity. Elective laparotomy was performed, and distal ileal atresia with sealed proximal perforation and a giant meconium pseudocyst were found. Resection of the involved small bowel, including the giant pseudocyst, followed by primary end-to-end anastomosis was performed smoothly. The postoperative course was uneventful. Advances in perinatal intensive care mean that neonates can be operated upon under stable rather than critical conditions, and elective rather than emergency laparotomy, and primary anastomosis of the intestine rather than staged enterostomy can be performed.

Isolated fetal ascites caused by bowel perforation due to colonic atresia

An isolated fetal ascites is a rare ultrasonographic finding. It is commonly diagnosed in association with fetal genitourinary or gastrointestinal conditions, mainly bowel obstruction. We present the sonographic features and neonatal outcome of a fetus with a large bowel obstruction, perforation and subsequent development of meconium peritonitis, prenatally diagnosed as isolated fetal ascites. A colonic atresia should be also included in the differential diagnosis of isolated fetal ascites.

"Growing" meconium cyst in one of a discordant twin: a case report

Introduction

Giant meconium cyst resulting from antenatal bowel perforation is rare and hardly reported in multiple gestations. We found only four documented cases in the electronic literature.

Case presentation

We report a giant meconium cyst in an 11-hour-old Nigerian boy of a discordant twin having ultrasonographic and plain radiographic diagnosis and surgical confirmation. Increasing abdominal girth from 35 cm to 41 cm within four hours of admission without ascites, pneumoperitneum and significant bowel distension make us assumed the meconium cyst to be “growing” in size. We reviewed the literature and proposed that where the fibrinous wall of meconium cyst allows for distensibility and the communication between the perforated bowel and meconium cyst persists, the meconium cyst acting as reservoir may continue to “grow” in size without remarkable intestinal distension probably, until the elastic limit is lost.

Conclusion

Meconium cyst can occur in twin pregnancy, grow to occupy the abdomen almost completely and may cause neonatal apnoea. The outcome is good post surgery.

Clinical manifestations in infants with symptomatic meconium peritonitis

BACKGROUND

Meconium peritonitis (MP) develops when bowel perforation occurs in utero or soon after birth, resulting in leakage of meconium into the peritoneal cavity. The clinical features are often variable and prenatal ultrasonography plays an important role in prenatal diagnosis.

METHODS

We conducted a retrospective review of neonates diagnosed with MP in our hospital from January 1998 to December 2007. Prenatal examinations, postnatal presentations, investigations, management, patient outcomes, and possible causes were analyzed.

RESULTS

Ten patients (five boys, five girls) diagnosed with MP were studied. The most common prenatal ultrasonographic finding was fetal ascites (7/10, 70%), followed by polyhydramnios (3/10, 30%), bowel dilatation (3/10, 30%), intra-abdominal calcification (1/10, 10%), and hydrops fetalis (1/10, 10%). Two of our patients were completely normal on prenatal ultrasonography. Only one MP diagnosis (1/10, 10%) was definitely confirmed by prenatal ultrasonography due to the presence of ascites, bowel perforation and intra-abdominal calcification. Nine patients (90%) required surgical intervention because of bowel perforation (5), bowel atresia (2), obstruction due to ileus (1), and intussusception (1). Peritonitis was of cystic type in one case (10%), fibroadhesive in five cases (50%), and generalized in four cases (40%). All 10 patients survived without long-term gastrointestinal complications.

CONCLUSION

Prenatal ultrasonography can be diagnostic for MP, which should be considered in the differential diagnosis of patients presenting with ascites or abdominal distension at birth. Close observation of postnatal clinical manifestations and timely surgical intervention resulted in a high survival rate and favorable outcome in these patients at our hospital.

Meconium peritonitis in utero---the value of prenatal diagnosis in determining neonatal outcome

OBJECTIVE

Meconium peritonitis (MP) is a chemical peritonitis caused by fetal intestinal perforation in utero. Its incidence is rare, but serious neonatal morbidity or even mortality can occur if the diagnosis is not made until after birth. Prenatal diagnosis is important in prompting early postnatal surgical intervention, and so improving neonatal outcome.

MATERIALS AND METHODS

Fourteen cases diagnosed in utero with MP from January 1996 to December 2005 were enrolled in this study. The final diagnoses were established by surgical findings or postnatal radiography. The prenatal ultrasound features, neonatal birth characteristics, surgical findings, postnatal management and neonatal outcomes were reviewed.

RESULTS

All infants received follow-up care at our hospital. Prenatal ultrasound findings included fetal ascites (100%), intra-abdominal calcification (93%), dilated bowel loops (57%), pseudocysts (29%), and polyhydramnios (50%). Four infants (4/14; 28.5%) did not undergo postnatal surgery, but survived well. The mean gestational age at detection was significantly earlier in the non-surgery group (23+/-3.6 weeks) than in the surgery group (31.7+/-2.5 weeks). One infant (7.1%) died because of sepsis after two neonatal operations. The overall survival rate was 92.9%.

CONCLUSION

MP can be diagnosed by prenatal ultrasound, and the neonatal outcome is favorable. Early detection is not associated with poor neonatal outcome, and selective termination is unnecessary. Resolution of dilated bowel loops and polyhydramnios predict a low rate of postnatal surgical intervention.

Prenatal detection of the cystic form of meconium peritonitis: no issues for delayed postnatal surgery

Prenatal ultrasound (US) diagnosis and postnatal outcome are reviewed in three babies with the complex form of meconium peritonitis (MP), the cystic type. Perinatal management is discussed. Large intra-abdominal cysts with signs of calcifications were detected during the second mid-trimester. Meconium ascites and polyhydramnios appeared between 32 and 35 weeks of gestation. Signs of anaemia were assessed on median cerebral artery peak systolic velocity. Sudden appearance of hydrops and anaemia required preterm delivery, neonatal resuscitation and urgent abdominal drainage. Postnatal US imaging confirmed prenatal sonographic evidence. Abdominal X-ray showed calcifications and no free abdominal air. Intestinal diversion was performed in two patients on their first day of life and evolution was uneventful. Hospital death occurred in one baby, who was submitted to delayed surgery due to unstable hemodynamic conditions. Distal ileal perforation walled off by pseudocysts was detected in all cases. One baby was found to be affected by cystic fibrosis. Ileal intussusception was described in the non-surviving infant. The cystic type of MP may have a potentially rapid lethal course and the onset of foetal anaemia and polyhydramnios is a bad prognostic factor. Severe evolution in hydrops and foetal distress may occur at any moment suggesting the persistence of a leakage or re-rupture of the cysts with new meconium spillage into the abdomen. Prenatal detection of ascites, polyhydramnios and pseudocysts requires a strict follow-up, and timing of delivery has to be planned in a tertiary centre. Postnatal radiological imaging does not offer further information over prenatal imaging and surgical decision should not be influenced by the absence of abdominal free air. Urgent abdominal drainage at birth, followed by intestinal diversion of persistent intestinal perforation on the first day of life, may prevent bacterial colonisation and improve prognosis.

Prenatal detection of the cystic form of meconium peritonitis: no issues for delayed postnatal surgery

Prenatal ultrasound (US) diagnosis and postnatal outcome are reviewed in three babies with the complex form of meconium peritonitis (MP), the cystic type. Perinatal management is discussed. Large intra-abdominal cysts with signs of calcifications were detected during the second mid-trimester. Meconium ascites and polyhydramnios appeared between 32 and 35 weeks of gestation. Signs of anaemia were assessed on median cerebral artery peak systolic velocity. Sudden appearance of hydrops and anaemia required preterm delivery, neonatal resuscitation and urgent abdominal drainage. Postnatal US imaging confirmed prenatal sonographic evidence. Abdominal X-ray showed calcifications and no free abdominal air. Intestinal diversion was performed in two patients on their first day of life and evolution was uneventful. Hospital death occurred in one baby, who was submitted to delayed surgery due to unstable hemodynamic conditions. Distal ileal perforation walled off by pseudocysts was detected in all cases. One baby was found to be affected by cystic fibrosis. Ileal intussusception was described in the non-surviving infant. The cystic type of MP may have a potentially rapid lethal course and the onset of foetal anaemia and polyhydramnios is a bad prognostic factor. Severe evolution in hydrops and foetal distress may occur at any moment suggesting the persistence of a leakage or re-rupture of the cysts with new meconium spillage into the abdomen. Prenatal detection of ascites, polyhydramnios and pseudocysts requires a strict follow-up, and timing of delivery has to be planned in a tertiary centre. Postnatal radiological imaging does not offer further information over prenatal imaging and surgical decision should not be influenced by the absence of abdominal free air. Urgent abdominal drainage at birth, followed by intestinal diversion of persistent intestinal perforation on the first day of life, may prevent bacterial colonisation and improve prognosis.

Fetal intra-abdominal calcifications from meconium peritonitis: sonographic predictors of postnatal surgery

OBJECTIVE

To study the relationship between prenatal ultrasound features and postnatal course of meconium peritonitis.

STUDY DESIGN

We reviewed our cohort of cases of meconium peritonitis (MP) (n = 13/37, 225 pregnancies or 0.3/1000) as well as those published in the English literature with prenatal ultrasonographic findings and postnatal follow-up (n = 56). The total number of cases (n = 69) was divided into 4 grades of progressive severity based on the number of pertinent sonographic findings: grade 0, isolated intra-abdominal calcifications (n = 18); grade 1, intra-abdominal calcifications and ascites (n = 17) or pseudocyst (n = 2) or bowel dilatation (n = 6); grade 2, two associated findings (n = 20); and grade 3, all sonographic features (n = 6). Presence of polyhydramnios was also recorded. Prenatal predictors of need for neonatal surgery and risk of neonatal death were identified using Chi-square and Fisher exact test, with P < 0.05 considered significant.

RESULTS

Neonatal surgical intervention was required in 0% (0/18) of newborns with grade 0 MP; in 52% (13/25) of those with grade 1; in 80% (16/20) with grade 2; and in 100% (6/6) with grade 3 MP (P < 0.001, Chi-square for trend). Moreover, neonatal surgery was more frequent in the presence than absence of polyhydramnios [69% (18/26) vs 37% (16/43); P = 0.007]. Neonatal mortality was 6% (4/69; 3 after surgery and 1 for premature delivery) and it was confined to the subgroup with polyhydramnios (4/26, 15%).

CONCLUSIONS

Prenatal sonographic features are related to postnatal outcome. Persistently isolated intra-abdominal calcifications have an excellent outcome. Delivery in a tertiary care center is recommended when calcifications are associated with other sonographic findings.

Experience with meconium peritonitis

BACKGROUND

Meconium peritonitis is a sterile chemical peritonitis resulting from intrauterine bowel perforation. With the development of neonatal care, the prognosis of meconium peritonitis improved much. We report our clinical experience.

METHODS

The medical records of patients with meconium peritonitis admitted to the Asan Medical Center from June 1989 to July 2006 were retrospectively reviewed.

RESULTS

Of 41 patients (17 males, 24 females), 38 (92.7%) were suspected to suffer from meconium peritonitis prenatally, at a median gestational age of 32 weeks (range, 21-40 weeks). The most common prenatal sonographic finding was fetal ascites followed by dilated bowel. Ten patients were managed conservatively, but 31 patients underwent operations including resection and anastomosis (22), drainage procedure (4), ileostomy (3) and primary repair (2). The operative 31 cases comprised generalized (16), fibroadhesive (10), and cystic types (5). 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. More gentle and delicate approach should be done to lower the morbidity.

Abdominal dystocia in a case of undetected intrauterine meconium peritonitis due to cystic fibrosis

The case of a 36 year-old primigravida is presented. After a normal anomaly scan at 22 weeks and a normal pregnancy, she went into labor at term. Dystocia due to massive abdominal distension complicated the second stage. The newborn girl had meconium peritonitis with colonic perforation and required colonic resection with colostomy. Genetic testing detected cystic fibrosis. In this case complex meconium peritonitis developed silently (without any clinical sign) after a normal anomaly scan. This has not been reported since the start of the widespread use of obstetric ultrasound. Late meconium peritonitis can escape detection and should be thought of in cases of unexpected abdominal distension causing dystocia.

Meconium peritonitis: prenatal diagnosis, postnatal management and outcome

OBJECTIVES

Prenatal ultrasonography (USS) is a routine screening test for fetal abnormalities. Its accuracy for detecting meconium peritonitis (MP), which may carry high mortality, is important for prenatal counseling. The aim of this study was to assess the accuracy of prenatal USS for diagnosing MP and predicting patient outcomes.

METHODS

The prenatal and postnatal medical records of all patients referred to our institutions with confirmed MP were reviewed, with emphasis on prenatal USS findings, results of postnatal investigations, operative findings, outcomes, and possible causes of MP.

RESULTS

From January 2000 to November 2004, seven fetuses were confirmed to have MP at birth. Three MP patients (3/7, 43%) were diagnosed prenatally because of USS showing ascites and calcification/dilated or hyperechoic bowel loops. One (1/7, 14.3%) suspected cystic MP was confirmed by prenatal MRI. In the other three cases, USS showed only ascites. All patients had postnatal contrast CT scans. Two patients' CT scans showed persistent intestinal perforation not visible with prenatal USS, and required emergency operations. All patients survived and prospered, and were sweat test negative.

CONCLUSIONS

Prenatal USS allows suspected MP babies to be transferred to a tertiary centre for delivery and appropriate management. In this way, the chances of survival of these babies can be excellent if they are not associated with cystic fibrosis (CF). Prenatal MRI can improve the low diagnostic yield of prenatal USS for MP. Postnatal contrast CT scan is required to define persistent intestinal perforation invisible with prenatal USS.

Infrared spectrophotometry of intraluminal meconium calculi in a neonate with imperforate anus and rectourethral fistula

BACKGROUND/PURPOSE

Intraluminal meconium calculi are a rare cause of neonatal abdominal calcifications in patients with anorectal malformations. To investigate their pathogenesis, we performed infrared spectroscopic analysis of meconium-calcified lesions.

METHODS

Meconium calculi were collected from the colostomy in a newborn patient with imperforate anus and rectourethral fistula. The potassium bromide method was employed to obtain the infrared absorption spectrum of the meconium calculi.

RESULTS

The wavelength pattern of the meconium calculi exhibited 4 specific peaks at 1570, 1390, 1105, and 1005 cm(-1) between 22% and 45% transmittance values. The unique absorption spectrum exclusively indicated ammonium hydrogen urate (C(5)N(5)O(3)H(7)), having the combined constituents of ammonium and uric acid.

CONCLUSIONS

These results suggest that the intraluminal meconium calculi were originally derived from meconium and fetal urine. The stasis of meconium passage and fetal urine mixing through the rectourethral fistula in a low-pH condition was deduced to be the main cause of this rare stone formation.

Intraabdominal fetal echogenic masses: a practical guide to diagnosis and management

Intraabdominal calcifications and other echogenic masses are relatively common findings during fetal sonography. Many are associated with no additional risk for the fetus or neonate. They may arise from the liver, gallbladder, spleen, kidneys, adrenal glands, gastrointestinal tract, or peritoneal cavity. Detection of such lesions should prompt a detailed survey for additional findings and a review of the maternal history. In some cases, fetal karyotyping may be indicated. In most cases, the diagnosis, management, and outcome are determined according to a combination of specific ultrasound appearances and at least one additional maternal or fetal factor. In utero diagnosis can often be achieved with careful evaluation of the lesion echotexture, associated calcifications, additional findings, and evolution over time. In most cases, expectant management is sufficient, but some patients require transfer to a facility where early postnatal intervention is available. A systematic approach to the findings aids in differential diagnosis and management.

Perforated tubular duplication of the transverse colon: a rare cause of meconium peritonitis with prenatal diagnosis

The transverse colon is an exceptional location of intestinal duplication. Perforated duplications are rarely described in neonates. Meconium peritonitis (MP) can originate from prenatal perforated intestinal duplication. The authors report a case of a baby girl with prenatal diagnosis of MP. Rapid worsening of clinical aspects at birth and the presence of a pneumoperitoneum on systematic abdominal plain radiographs led to urgent surgery on the 1st day of life. Laparotomy showed a perforated necrotizing tubular duplication of the transverse colon. Removal of the duplication followed by limited segmental colonic resection and double colostomy were carried out. Follow-up was uneventful.

Prenatal diagnosis and management of abdominal diseases in pediatric surgery

PURPOSE

The aim of this study was to investigate the prenatal courses and management of abdominal surgical diseases.

METHODS

Of the 327 patients registered with our fetal treatment board since March 2002, 83 fetuses referred to the surgical department were enrolled for the current study. The prenatal diagnosis, sequential fetal images, and perinatal courses of these cases were reviewed retrospectively.

RESULTS

Of the 83 cases, abdominal diseases were suspected in 34, lung and thoracic diseases in 25, genitourinary diseases in 12, and other anomalies in 12. Meconium peritonitis (MP), intestinal obstruction, and abdominal wall defects accounted for approximately 65% of the abdominal diseases. Five patients with prenatally diagnosed lung diseases underwent fetal surgical intervention, and 17 of the 22 liveborn patients survived. In contrast, none of the patients with prenatally diagnosed abdominal anomalies underwent fetal surgical intervention, yet, 23 of the 24 liveborn patients survived. However, preterm labor and hydrops were seen frequently in the patients with giant cystic MP, suggesting a fetal critical condition.

CONCLUSIONS

Although the clinical outcome of abdominal diseases seemed favorable with postnatal treatment, the current results suggested the occurrence of hidden mortality in utero and the potential need for fetal intervention for some abdominal conditions, such as MP.

Meconium peritonitis and pseudo-cyst formation: prenatal diagnosis and post-natal course

OBJECTIVES

Intra-uterine bowel perforation can occur secondary to a variety of abnormalities and cause sterile peritonitis in the fetus (generalised = type I). If sealing of the perforation does not take place, a thick-walled pseudo-cyst can form (type II).

METHODS

Over a 12-year period, 21 616 pregnancies were screened for gastro-intestinal malformations using prenatal ultrasound. We identified 1077 cases suspicious of surgically correctable malformations. Post-natal diagnoses and outcome were worked up retrospectively.

RESULT

We found 96 fetuses with suspected gastro-intestinal malformations. Prenatal bowel perforation with meconium peritonitis was confirmed in 11 cases. In 5 of these 11, the correct diagnosis had been predicted prenatally. One child presented as a fetal and neonatal emergency (case report). Ten of the eleven infants were operated on during their first day of life. Intra-operative findings were atresia (n = 4), meconium ileus (n = 6) and no obvious cause (n = 1). Two children suffered fatal complications.

CONCLUSION

Meconium peritonitis and meconium pseudo-cysts as its special manifestation are assessable by prenatal diagnosis but present in different ways. They can present as fetal ascites or echogenic bowel and cause fetal or neonatal distress, requiring close observation and highly specialised care.

Correlation of prenatal ultrasound and postnatal outcome in meconium peritonitis

OBJECTIVES

To study the relationship between prenatal ultrasound features and postnatal course of meconium peritonitis.

METHODS

Meconium peritonitis was diagnosed by prenatal ultrasound. Fetuses were treated by intrauterine paracentesis of ascites when indicated, and symptomatic newborns received surgery.

RESULTS

Totally 17 cases were enrolled. Prenatal ultrasound findings include abdominal calcification (16/17), fetal ascites (12/17), hydramnios (9/17), pseudocyst (7/17) and dilated bowel loop (6/17). Persistent ascites, pseudocyst or dilated bowel loop are most sensitive (92%) to predict postnatal surgery (p = 0.022). The survivors have a higher gestational age at birth (36.4 vs. 33.3 weeks, p = 0.008). Persistent ascites and postnatal persistent pulmonary hypertension of the newborns significantly correlate with neonatal mortality (p = 0.029 and 0.022).

CONCLUSION

Prenatal ultrasound can predict the neonatal outcome in meconium peritonitis.

Meconium dependence of bowel damage in gastroschisis

BACKGROUND/PURPOSE

Increasing evidence of physiologic in utero defecation supports the hypothesis that bowel damage in gastroschisis may be meconium dependent. In this study, the author investigated the role of meconium on parameters of bowel damage in a fetal rat model of gastroschisis.

METHODS

Pregnant rats underwent laparotomy at 18 1/2 days gestational age (GA). There were 4 experimental groups of 11 fetuses each; the G(M) group consisted of fetuses with isolated gastroschisis and was considered to have moderate meconium contamination of the amniotic fluid (MCAF); the G(L) group consisted of fetuses with gastroschisis and anal ligation, performed to prevent MCAF; the G(H) group consisted of fetuses with gastroschisis and colon perforation, performed to increase MCAF; and the Sham group consisted of sham operated controls. All fetuses were harvested by cesarean section at 21 1/2 days GA, and the fetal intestine was assessed for peel, intestinal length, intestinal weight per unit length, and histologic appearance.

RESULTS

The authors achieved the following fetal survival rates: G(M) group, 91% (10 of 11); G(L) group, 78% (7 of 9, the ligation was not successful in 2 fetuses); G(H) group, 82% (9 of 11). Sham group, 100% (11 of 11). Intestinal length was decreased in fetuses with gastroschisis, and this reduction was related directly to the grade of MCAF (Sham, 18.4 +/- 0.6; G(L), 11.5 +/- 0.5; G(M), 10.2 +/- 0.6; G(H), 9.1 +/- 0.6 cm; P <.01). In contrast, intestinal weight per unit length increased in fetuses with gastroschisis, and this increase was related directly to the grade of MCAF (Sham, 7.8 +/- 0.5; G(L), 9.4 +/- 0.5; G(M), 11.3 +/- 0.5; G(H), 16.9 +/- 0.7 mg/cm; P <.01). In comparison with the G(M) group, the degree of peel coverage and bowel adherence were increased markedly in the G(H) group, whereas the fetuses of the G(L) group had neither peel nor bowel adherence.

CONCLUSIONS

All bowel damage parameters were affected by MCAF supporting the hypothesis that bowel damage in gastroschisis is at least partially dependent on meconium exposure. Further research is required to clarify other factors that contribute to bowel damage and to identify risk factors that may allow prenatal identification of severely affected fetuses.