Maternal ultrasonography for the antenatal diagnosis of surgically significant neonatal anomalies

CRISPR-Cas9-Mediated Gene Therapy in Neurological Disorders

Neurological disorders are primarily diseases with sophisticated etiology that are always refractory and recrudescent. The major obstruction to effective therapies for neurological disorders is the poor understanding of their pathogenic mechanisms. CRISPR-Cas9 technology, which allows precise and effective gene editing in almost any cell type and organism, is accelerating the pace of basic biological research. An increasing number of groups are focusing on uncovering the molecular mechanisms of neurological disorders and developing novel therapies using the CRISPR-Cas9 system. This review highlights the application of CRISPR-Cas9 technology in the treatment of neurological disorders, including Alzheimer's disease, amyotrophic lateral sclerosis and/or frontotemporal dementia, Duchenne muscular dystrophy, Dravet syndrome, epilepsy, Huntington's disease, and Parkinson's disease. Hopefully, it will improve our understanding of neurological disorders and give insights into future treatments for neurological disorders.

Somatic gene editing ameliorates skeletal and cardiac muscle failure in pig and human models of Duchenne muscular dystrophy

Frameshift mutations in the DMD gene, encoding dystrophin, cause Duchenne muscular dystrophy (DMD), leading to terminal muscle and heart failure in patients. Somatic gene editing by sequence-specific nucleases offers new options for restoring the DMD reading frame, resulting in expression of a shortened but largely functional dystrophin protein. Here, we validated this approach in a pig model of DMD lacking exon 52 of DMD (DMDΔ52), as well as in a corresponding patient-derived induced pluripotent stem cell model. In DMDΔ52 pigs1, intramuscular injection of adeno-associated viral vectors of serotype 9 carrying an intein-split Cas9 (ref. 2) and a pair of guide RNAs targeting sequences flanking exon 51 (AAV9-Cas9-gE51) induced expression of a shortened dystrophin (DMDΔ51-52) and improved skeletal muscle function. Moreover, systemic application of AAV9-Cas9-gE51 led to widespread dystrophin expression in muscle, including diaphragm and heart, prolonging survival and reducing arrhythmogenic vulnerability. Similarly, in induced pluripotent stem cell-derived myoblasts and cardiomyocytes of a patient lacking DMDΔ52, AAV6-Cas9-g51-mediated excision of exon 51 restored dystrophin expression and amelioreate skeletal myotube formation as well as abnormal cardiomyocyte Ca2+ handling and arrhythmogenic susceptibility. The ability of Cas9-mediated exon excision to improve DMD pathology in these translational models paves the way for new treatment approaches in patients with this devastating disease.

Prenatal diagnosis of a rare form of congenital mid-ureteral stricture: a case report and literature revisited

Background

Congenital mid-ureteral stricture is a rare malformation of the ureter leading to prenatal and neonatal hydronephrosis. Site characterization of the narrowing is important to optimize the surgical approach to the newborn affected by hydronephrosis.

Case presentation

We report a female EM with a rare form of hydronephrosis, (i.e. mid-ureteral stricture) which was detected early during pregnancy by imaging techniques. During fetal life both conventional fetal Ultrasound and maternal Magnetic Resonance Imaging (MRI) were used to diagnose the obstruction. Magnetic Resonance pyelography and retrograde Ureteropyelography were performed after delivery and before surgical correction and confirmed the finding.

Furthermore, we revisited the literature using online MEDLINE and EMBASE databases. The literature reported only a few cases of prenatal diagnosis of early onset mid-ureteral stricture.

Conclusion

Mid-ureteral stricture is a rare cause of prenatal hydronephrosis. The diagnosis should not be delayed in order to apply the appropriate surgical approach. As a result, we showed the usefulness of fetal MRI and postnatal Magnetic Resonance pyelography, in the event that radionuclide renography with Tc-MAG3 was less informative, to allow the detection of the site of ureteral narrowing. Intrasurgical retrograde ureteropyelography confirmed these findings.

Autoamputation of ovarian cyst in an infant

A right ovarian cyst was detected in a 34-week-gestation fetus on antenatal ultrasound scan (USS). Postnatal USS confirmed the presence of the cyst and showed it to be 4.6 cm in diameter. The cyst failed to resolve after a period of conservative management, and therefore surgical removal was performed. During the operation a free autoamputated right ovarian cysts was found. The complication had not been detected preoperatively in spite of regular USS follow-up.

Intestinal dilatation in the fetus

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Antenatal fetal diagnosis and maternal transport gastroschisis. A maternal-infant case report

Gastroschisis is a rare congenital birth defect of the abdominal wall that invariably is fatal if not managed appropriately. Early in utero diagnosis is now possible using maternal serum alpha-fetoprotein and ultrasound. As with other serious congenital disorders, antenatal diagnosis allows therapeutic options and time for preparation. Even if the diagnosis is made late, however, efforts to achieve prenatal maternal transport are still reasonable. The neonatal outcome of an unplanned delivery of an anomalous child requiring immediate attention is likely to be better if the delivery occurs in a tertiary center. These facilities generally have specialized services and teams available for critical care around the clock. The authors describe the maternal transport and delivery of a neonate with a serious disorder that required specialized attention at an hour when most hospitals are staffed with a skeleton crew. The necessary resources were available immediately, and the neonatal outcome was favorable. Although this report describes gastroschisis specifically, the concept of tertiary site delivery for potentially seriously ill neonates applies to any condition. With a late diagnosis, possible other anomalies, and a logistically unfavorable hour, the advantages of maternal transport are evident. This report also briefly reviews the area of antenatal ultrasound diagnosis and the newer mechanisms used to develop a perinatal care plan.

Unexpected dystocia secondary to a fetal sacrococcygeal teratoma: a successful outcome

Sacrococcygeal teratoma is a rare cause of dystocia. With recent advances in perinatal care, particularly the increasing use of maternal ultrasound, it is unlikely that unexpected dystocia secondary to this tumor will be seen by many physicians. Recent reports of this type of dystocia are rare and infant mortality secondary to it is high. However, if and when encountered, such dystocia need not imply a bad prognosis for either mother or infant. This is a report of successful management of one case as well as a presentation of recently reported cases and recommendations for management.

Intrauterine Diagnosis of Abdominal Wall Defects

Ultrasound is an important tool in the evaluation of fetal development and detection of fetal abnormalities. The ability to detect abnormalities in utero can help improve perinatal care; therefore, a detailed sonographic examination of the fetus should always be obtained. Abdominal wall defects that can be recognized by sonography include omphalocele, gastroschisis, umbilical cord hernia, and limb/body wall complex. The sonographer should attempt to give a detailed description of the defect including the organs involved, the presence of a sac, the site of cord insertion, and the presence of any associated anomalies. This information can aid the physician and parents in determining the course of management of the pregnancy.

Management of ovarian cyst detected antenatally

Ovarian cyst was diagnosed in nine fetuses by antenatal ultrasonographic examination. All deliveries were uncomplicated; two were delivered by cesarean section. The clinical condition in all cases was good. Five of the neonates with a large cyst (more than 5 cm in diameter) were managed surgically, while four were merely followed with repeated ultrasonic examinations. In three of the latter four infants, the cysts disappeared without clinical complications during the subsequent 12 months, and one has been followed for only 2 weeks. The treatment of neonatal ovarian cyst is controversial. Since small ovarian cysts are not clinically significant and may involute, conservative treatment after birth is possible. Repeated ultrasonographic examination may be used to follow small cysts in asymptomatic patients. However, surgical excision in the newborn period has been suggested for larger lesions and/or those with solid components inside the cyst before life-threatening complications occur.

Surgical problems in the fetus: a multidisciplinary approach

Over a 2 year period, 90 cases of potential fetal pathologic conditions were presented to a multidisciplinary fetal board. Members, including persons from perinatology, neonatology, genetics, radiology, pathology, pediatric surgery, neurosurgery, and urology, met monthly to discuss new referrals, follow-up ongoing cases, and present findings and treatment in delivered cases. Of 90 referred cases, 76 surgical diagnoses occurred in 71 fetuses (79 percent), with central nervous system and genitourinary anomalies predominating. A formal presentation during a single meeting with the variety of specialists necessary to manage surgical problems in the fetus facilitated perinatal management and allowed for the appropriate specialist to counsel the parents as early as possible.

Prenatal diagnosis and management of congenital defects of the anterior abdominal wall

Between the years 1980 and 1985, 25 cases of anterior abdominal wall defects were identified within the University of Toronto Perinatal Complex. There were 17 cases of omphalocele and eight cases of gastroschisis. Associated anomalies were found in 71% of infants with omphalocele and 50% with gastroschisis. They were the major cause of neonatal death. Prematurity was the second most common cause of death. The neonatal death rate was 59% in omphalocele and 38% in gastroschisis; the prematurity rates were 53% and 50%, respectively. In omphalocele, there was a 47% cesarean section rate, with a 50% neonatal death rate. Vaginal delivery was associated with a 67% death rate. In gastroschisis, there was a 50% cesarean section rate, with a 50% neonatal death rate. Vaginal delivery was associated with a 25% death rate. There is no evidence that cesarean section offers improved neonatal survival.

Prenatal ultrasonic diagnosis of anterior abdominal wall defects

Nine cases of different types of anterior abdominal wall defects were diagnosed prenatally by ultrasound: gastroschisis (one case), omphalocele (five cases), exstrophy of the cloaca (one case) and the extreme form of prune belly syndrome (two cases). The ultrasonic features of gastroschisis and omphalocele are well recognized by most experienced sonographists. The ultrasonic prenatal diagnosis of exstrophy of the cloaca has not been reported previously and it is a very rare entity. The anterior abdominal wall defect is larger than in omphalocene and is located infraumbilically. Fetal ascites and a lumbosacral myelomeningocele are present as well. The extreme form of prune belly syndrome is associated with the absence of the abdominal wall musculature and marked dilatation of the urinary tract, presented ultrasonically as multiple large cysts occupying the distended fetal abdominal cavity. The differential diagnosis of these entities and guidelines for their correct prenatal ultrasonic diagnosis will be discussed.

Prenatal diagnosis of fetal malformations by ultrasonography

Ultrasonography is today able to detect many details of the fetal anatomy, so that prenatal diagnosis of malformations becomes possible. However, as 60% of all detected fetal abnormalities develop spontaneously, a screening program is recommended. At least two ultrasonic examinations should be performed. To cope with the huge number of examinations obstetricians in their offices are integrated in this program. Women carrying fetuses with identified or suspected anomalies are sent for further evaluation, management, and counseling to special clinics. The task is to differentiate between lesions which are incompatible with postnatal life, lesions which will necessitate a supporting person for the life of the patient, and lesions which are correctable by surgery. To gain more experience, close cooperation with neonatologists, pediatric surgeons, neurologists, and geneticists is recommended. The first advantages of early prenatal diagnosis have been elective cesarean and reduction of postnatal evaluation and treatment required.

Ultrasonographic anatomy and diagnosis of fetal uropathies affecting the upper urinary tract. I. Obstructive uropathies

The authors describe the ultrasonographic anatomy and semiology of allowing detection of the main types of fetal uropathies. The results of the author's personal experience in this domain are compared to data from the literature. Differential features of the uropathies are given and the limitations and practical significance of prenatal and postnatal ultrasonography are discussed.

Prenatal diagnosis of congenital anomalies requiring surgical correction. Implications for the future

With the use of maternal ultrasonography, 22 infants had an anomaly identified before delivery. Nine had gastrochisis. In all, ultrasonography was performed because of an elevated maternal serum alpha 1 fetoprotein level. Ultrasonography for other indications identified three infants with omphaloceles, three with cystic adenomatoid malformation of the lung, two with duodenal atresia, two with posterior urethral valves, and one each with obstruction of the ureteropelvic junction, a retroperitoneal teratoma, and an ovarian cyst. Infants were delivered in a neonatal center able to provide total care from the time of birth, thus the risks of transport over long distances were avoided. One of the infants with cystic adenomatoid malformation was incorrectly diagnosed as having a congenital diaphragmatic hernia, and the complete posterior urethral valve bilateral hydronephrosis complex was not identified in this infant until after delivery. The ability to diagnose complex anomalies correctly places new responsibilities on the surgeon who must counsel the parents on his ability to successfully treat the identified anomaly. Improved diagnostic accuracy, increased case findings, careful counselling, and delivery of high-risk infants in regional centers must be major priorities to improve neonatal surgical care in the next decade.

Gastroschisis and omphalocele: prenatal diagnosis and perinatal management

Obstetric ultrasonography has made the prenatal diagnosis of gastroschisis and omphalocele more common. We present illustrative cases and review the ultrasonographic features. Because of the increased risk of concomitant abnormalities (including trisomies) with omphalocele, full evaluation is indicated when this diagnosis is suspected. Recent perinatal approaches to delivery have favoured caesarean section, without scientific evidence that outcome is improved. Our experience, as well as a review of the literature, suggests that the outcome for vaginally delivered infants is acceptable. A prospective study of this question is needed.

Ultrasonographic antenatal diagnosis: will it change the spectrum of neonatal surgery?

The outcome of 139 fetuses with anatomical abnormalities diagnosed by ultrasonography (out of 15,180 examinations) at our institution during the last 6 years was reviewed. Of these, 56 were diagnosed before 21 weeks gestational age and 83 thereafter. Fifty-four had anomalies of the central nervous system. Of these 27 were diagnosed early. Twenty-six had anomalies of the genitourinary tract, 11 diagnosed early. Four had anomalies of the musculoskeletal system diagnosed early in 3. Thirty-seven had miscellaneous anomalies and early diagnosis was made in 6. Only the early pregnancies were terminated, 38 in number. The fetal diagnosis was clearly confirmed in 33. Of particular interest were the 18 fetuses with anomalies of the gastrointestinal tract and abdominal wall. There were nine early diagnoses. The pregnancy was interrupted in seven. In all the diagnosis was confirmed. Five of these had associated anomalies. Among the 9 fetuses whose anomalies were diagnosed late, 3 had associated anomalies and died shortly after birth before corrective surgery. In all, two fetuses with abdominal wall defects had no detectable associated anomalies and were potentially correctable but the pregnancies were terminated. With earlier, accurate imaging diagnosis possible, special attention has to be directed toward multidisciplined counseling (including a pediatric surgeon) for ultimately satisfactory fetal-neonatal salvage. Otherwise the spectrum of neonatal surgical pathology could be seriously altered.

Prenatal diagnosis of unilateral hydronephrosis with early postnatal reconstruction

Real-time ultrasound systems, being used extensively now in obstetrical practice for fetal monitoring, are providing the urologist with more opportunities for early recognition and intervention of congenital hydronephrosis. Thorough postnatal investigation to confirm a diagnosis is advocated. An early postnatal surgical repair can be performed successfully.

Ultrasound diagnosis and perinatal management of surgically correctable fetal malformations

Among 276 fetal malformations detected during the nine year period there were 97 potentially correctable anomalies which are described in detail as are the antenatal and postnatal corrective procedures undertaken. On 35 hydrocephalic fetuses 9 were operated upon postnatally in the last 2 yr. Three months after the operation four of the babies were found to be developing normally, three moderately well while two were severely retarded. Two out six babies with cystic hygroma were successfully operated after birth and their development is now normal. Of 23 malformations of the gastro-intestinal tract (two diaphragmatic hernias, three esophageal, four duodenal and four jejunal atresias, seven omphalocele, three gastroschisis) 13 babies were successfully operated and are developing normally. In 8 out of 10 antenatally detected cases of obstructive uropathy antenatal intervention was undertaken. In one case a shunt catheter was inserted for the last three weeks before delivery. Puncture and urine evacuation was performed in seven of the babies. Five were live born and surgical correction was successfully undertaken after birth, while two died (one multiple malformations and the other respiratory distress syndrome). After excluding multiple and chromosomal anomalies the best results are obtained in the correction of gastro-intestinal tract atresia (9 of 11) and obstructive uropathy (5 of 7), where once a passage has been established the baby develops normally. Interventions such as shunts in hydrocephalic babies are always a matter for discussion in relation to the final outcome, but when there is no other choice, this too is a way of endeavouring to help such a baby. Early antenatal diagnosis is therefore extremely important when interruption of pregnancy is still feasible. In cases of malformations detected at a later gestational age early diagnosis facilitates the assessment of the development of the affected organ, possible timely antenatal correction, team consultation regarding the time and mode of delivery and preparations for postnatal correction. Such an antenatal approach makes it possible to significantly influence the perinatal outcome.

Incidental fetal hydronephrosis: clinical implication

Maternal ultrasonography performed after twenty weeks of gestation is able accurately to identify and diagnose fetal hydronephrosis. We believe this finding should serve to alert the obstetrician as well as the pediatrician to potential complications which may arise at the time of delivery or immediately thereafter. Urologic evaluation and definitive surgical repair may then be performed when indicated.

Gonococcal ventriculitis associated with ventriculoamniotic shunt placement

Use of a ventriculoamniotic shunt to control fetal hydrocephalus is a new procedure. Early experience suggests possible benefit to the fetus. Complications have been rare. This report describes the first case of Neisseria gonorrhoeae central nervous system infection associated with a ventriculoamniotic shunt and the third case reported in a neonate. On the basis of this clinical experience, we recommend that the mother be monitored closely for cervical pathogens, that delivery be performed prior to amniorrhexis, and that culturing of the shunt and ventricular fluid be carried out at delivery.

Obstetric management of the fetus with omphalocele or gastroschisis: a review and report of one hundred twelve cases

The prenatal diagnosis of an abdominal wall defect in the fetus has led some obstetricians to recommend delivery by cesarean section in order to avoid trauma to the defect and reduce the risk of dystocia. A review was made of the obstetric management of 112 infants with abdominal wall defects who were admitted to a neonatal surgical unit. Cesarean section was performed in 16%, but no cesarean sections were performed because of the prenatal diagnosis, which was made in only four cases. The mortality rate for infants with omphalocele was 29%, and that for infants with gastroschisis was 13.5%. Visceral injury from the delivery process was suggested in one case. Decisions about obstetric management were made in the absence of the knowledge of the anomaly, and vaginal delivery did not appear to adversely affect outcome. It remains to be seen whether more accurate prenatal diagnosis will identify subgroups of infants who would benefit by cesarean section. Until that time, elective cesarean section does not seem to be justified.

Maternal ultrasound in neonatal surgery

Maternal ultrasound is commonly used for the evaluation and followup of pregnancy. Increasing experience in this field has led to the accurate sonographic description of both normal and abnormal fetal anatomy and to the antenatal diagnosis of increasing numbers of surgically correctable conditions. Antenatal diagnosis has the potential of greatly benefiting obstetrical care, the counseling and advising of parents, and perinatal surgical management. The use of intrauterine fetal surgery and/or manipulation may provide increased salvage of fetuses with diaphragmatic hernia and obstructive uropathy in the future. With the known safety and noninvasiveness of maternal sonography it may become a useful screening procedure for all pregnancies.