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Blood samples were obtained by fetoscopy from 30 fetuses in the middle trimester of pregnancy. The results indicate that high concentrations of renin and relatively low levels of renin substrate are present in the fetus early in pregnancy. These values are similar to those previously demonstrated in the full-term fetus.
Increase in maternal anti-D concentrations after intrauterine investigation has been studied retrospectively in 95 rhesus (D) alloimmunized pregnancies; 48 were managed by fetal blood sampling (FBS) procedures (using fetoscopy or ultrasound-guided needle sampling) and 47 using amniocentesis. In those pregnancies where the fetus was rhesus (D) positive, the frequency of procedure-related increases (greater than 50%) in maternal anti-D potency was estimated following single procedures and found to be similar for the two methods of FBS employed (28%) and for amniocentesis (31%). The proportion of pregnancies showing an increase in anti-D potency was higher after ultrasound-guided needle sampling (75%) than after fetoscopic FBS (40%) and after amniocentesis (44%).
Complement factors (C3, C4, C5; Factors B, H and I) were measured in maternal and fetal serum and amniotic fluid obtained from 55 women with singleton pregnancy undergoing diagnostic fetoscopy at 15 to 28 weeks gestation. Maternal serum levels were consistently 10 times higher than fetal levels which in turn were 10 times higher than levels in amniotic fluid. Spearman rank correlation analysis at weeks 20 to 22 (n = 20) revealed a statistically significant correlation between maternal and fetal levels of C3 and Factors B and I, and between maternal and amniotic fluid levels of Factors B and I. A significant increase in fetal levels of C3, C4 and Factor H, and in amniotic fluid levels of C3 and Factor B was seen in relation to advancing gestational age. These differences were not seen in maternal serum during the short interval of pregnancy studied. These data confirm earlier assumptions of fetal synthesis of complement factors, and provide normal reference ranges of complement factors in fetal blood and amniotic fluid.
OBJECTIVE: To investigate maternal and fetal folate and vitamin B12 concentrations in pregnancies affected by neural tube defects (NTD). DESIGN: Measurement of folate and vitamin B12 concentrations in amniotic fluid, fetal blood and maternal blood samples in midgestation. SUBJECTS: 32 women undergoing termination of pregnancy at 14-21 weeks gestation for social reasons (n = 24) or for fetuses with neural tube defects (n = 8). INTERVENTIONS: Fetoscopy before intra-amniotic injection of prostaglandins. RESULTS: In normal pregnancies there was a positive correlation between maternal and fetal serum folate, and the fetal serum and red blood cell folate concentrations were higher than the maternal. There were no differences in amniotic fluid, maternal blood or fetal blood folate concentrations between pregnancies with NTD and normal pregnancies. Although amniotic fluid vitamin B12 was lower in pregnancies with NTD, maternal serum vitamin B12 concentration was not reduced. CONCLUSION: In this small group of pregnancies with NTD at mid-gestation there is no evidence to suggest folate or vitamin B12 deficiency.
A female infant born to a mother who had an elevated serum alpha-fetoprotein during early pregnancy, presented a combination of epidermolysis bullosa and aplasia cutis congenita. She developed evidence of upper gastrointestinal obstruction and died at the age of 43 hours. Post-mortem examination showed the presence of pyloric atresia and electron microscopy of skin biopsies showed epidermolysis bullosa simplex. Examination of the placenta revealed a unique abnormality of the membranes, indicating the existence of two sacs. This case and the previously reported cases, which are reviewed, suggest an autosomal recessive inheritance. Serum alphafetoprotein estimation, ultrasonography and fetoscopy with skin biopsy are suggested as a means of pre-natal diagnosis in future pregnancies.
We reviewed the hepatic features in 136 children with alpha 1 antitrypsin deficiency (PiZ). Eighty two were studied prospectively, 74 of whom had chronic liver disease. Sixty seven children with liver disease presented in the first four months of life, four were older infants and children with chronic liver disease, 10 (three with liver disease) were identified in studies of the family of these propositi, and one was identified when she had liver disease associated with infectious mononucleosis. By 17 years of age 20 of these 74 children with chronic liver disease had died, 20 had established cirrhosis, 19 had persisting liver disease, and only 15 had made a complete, clinical and biochemical recovery. The outcome of liver disease was similar in a further 39 previously unreported PiZ infants and children with liver disease who were not prospectively studied. Because liver disease affects only a proportion of infants with PiZ phenotype and because the severity of their liver disease is so variable, we have analysed the outcome of liver disease in 27 observed families and in 20 previously reported families with more than one child with PiZ. In 34 families the outcome of liver disease was similar in the two children. From an analysis of the families with a severely affected child, we conclude that if the first PiZ child of PiZ heterozygote parents has unresolved liver disease, there is a 78% chance that a second PiZ child will have similar liver disease. After careful counselling, fetoscopy, fetal blood sampling, and protease inhibitor phenotyping, possible termination of pregnancy should be carefully considered in these families.
Normal reference ranges for sodium, potassium, urea, creatinine, calcium, phosphate, total protein, albumin, bilirubin, alkaline phosphatase, and aspartate transaminase were determined from 344 fetal and maternal plasma samples between 15 and 38 weeks' gestation. Pure fetal blood was obtained by fetoscopy in the second trimester and in the third trimester by umbilical cord puncture at delivery. All biochemical substances were measured by continuous flow (SMAC, Technicon) except albumin, which was measured by turbidimetry (CobasBio, Roche). The resulting data were analysed on an AMDAHL 470A computer and reference ranges covering 2.5 to 97.5 percentiles were defined. Analysis of variance was performed to examine the overall effect of gestational age on the analytes measured and on the changes in the fetal compartment relative to the mothers'. A paired t test was performed to examine how these biochemical substances in fetal plasma related to maternal plasma from the same pregnancy.
The prenatal diagnosis of bullous ichthyosiform erythroderma (BIE) has been achieved at 20 weeks' gestation by electron microscopic identification of a pathognomonic cytoskeletal abnormality within fetal epidermal cells obtained by fetoscopic skin biopsy. The same abnormality was also observed in skin derived amniotic fluid cells. The question whether amniocentesis might be used instead of fetoscopy for future prenatal detection of BIE is discussed.
Three new cases of the Fraser syndrome are presented and 68 published cases are reviewed. A quantitative estimate of the frequency of clinical manifestations is given. Craniofacial abnormalities were reported in all patients, cryptophthalmos in 93%, and syndactyly in 54%. Abnormalities of the ears, nose, genitalia, and urinary system were reported in 44%, 37%, 49%, and 37% of cases respectively. This variability should be taken into account when attempting prenatal diagnosis; a combination of ultrasound and fetoscopy should provide the best approach. Of the reported cases 26% were stillborn and 19% died in the first year of life. Renal and pulmonary malformations were associated with early death.
Despite the morbidity and mortality associated with early midtrimester premature rupture of the membranes (PROM), limited therapeutic options currently exist for its treatment. A new operative approach to this condition termed embolization involves intra-uterine administration of a gelatin sponge which can remarkably reduce or eliminate further loss of amniotic fluid. A successful case of embolization for the treatment of iatrogenic previable PROM complicating therapeutic fetoscopy is described.
OBJECTIVE: To compare the electrolyte composition of pregnancies complicated with twin-twin transfusion syndrome (TTTS) with that of physiologic pregnancies. MATERIALS AND METHODS: Amniotic fluid samples from 16 pregnancies were studied. Specimens were obtained from recipient sacs in 10 pregnancies undergoing fetoscopy for severe midtrimester TTTS. Additionally, 6 amniotic fluid samples were obtained transcervically from legal second-trimester pregnancy terminations. The concentrations of sodium, potassium, chloride, bicarbonate, calcium, glucose, osmolality, pH, total protein content and albumin were determined in each sample. RESULTS: The mean gestational age at sampling was 20.2 weeks (range 17.2-27.1) in the TTTS group and 18.4 (range 16.0-22.0) in the control group (p = NS). We found significant lower levels of albumin (0.22 +/- 0.04 vs. 0.39 +/- 0.11, p = 0.01) and total protein (0.19 +/- 0.08 vs. 0.51 +/- 0.17, p < 0.001) and higher levels of bicarbonate (16.90 +/- 1.45 vs. 14.50 +/- 2.17, p = 0.02) in amniotic fluid samples taken from recipient sacs of TTTS pregnancies. CONCLUSION: Amniotic fluid from the receptor in severe midtrimester TTTS differs significantly from control amniotic fluid samples in bicarbonate concentration, total protein content and albumin concentration. These findings may help to understand the pathophysiology of TTTS and to optimise therapeutic modalities.
OBJECTIVES: To evaluate the changes in the approaches used for invasive prenatal diagnosis for beta-thalassemia and karyotyping at a single center from 1977 to 2004. METHODS: For beta-thalassemia, in 1977 placentacentesis, in 1982 amniocentesis, in 1983 fetoscopy and cordocentesis, in 1983 trancervical chorionic villi sampling (TC-CVS), in 1984 cardiocentesis, in 1986 transabdominal CVS, and in 2002 preimplantation genetic diagnosis (PGD) were introduced. For karyotyping, in 1977 amniocentesis, in 1983 cordocentesis and cardiocentesis and TC-CVS, in 1986 TA-CVS and in 1991 hepatic vein sampling were introduced. Rates of approaches used were retrospectively considered, for 5 different groups (1977-1981; 1982-1985; 1986-1993; 1994-1999; 2000-2004). RESULTS: 35,127 invasive prenatal diagnoses were considered, and 42 PGD included. For beta-thalassemia 6,547 diagnoses were performed and 42 PGD. Since 1986-1993, TA-CVS was the only approach used except for 42 PGD in the 2000-2004 group. For karyotyping 28,538 diagnoses were performed. Amniocentesis and TA-CVS have been the most frequently used in the last years, while cordocentesis and hepatic vein sampling have shown a decline after their introduction. CONCLUSION: TA-CVS is now the only technique used for beta-thalassemia. For karyotype, amniocentesis and TA-CVS are the most frequently used procedures. Obstetrical and laboratory experience, the availability of screening, and other individual factors, have influenced the choice, towards an earlier approach in pregnancy.
The hemoglobin content of single erythrocytes was determined by microspectrophotometry as total extinction (TE) at 415 nm in subjects with a wide spectrum of hemoglobin levels and erythrocyte indices. Precise measurements of the cellular area (A) and the ratio TE/A were also recorded. A significant correlation was found between TE and mean corpuscular hemoglobin (MCH), A and mean corpuscular volume, and TE/A and mean cell hemoglobin concentration (MCHC) for the cases studied. In addition, TE, A and TE/A were determined in fetal erythrocytes obtained by fetoscopy at the 20th week of gestation for prenatal diagnosis of beta-thalassemia. The mean red cell TE and TE/A of the group of fetuses diagnosed to have thalassemia major were significantly lower than those of the group of normal controls and with heterozygous beta-thalassemia. The significant differences of TE, A and TE/A between maternal and fetal blood allowed a safe distinction of the latter. The calculated MCH of the fetuses with thalassemia major was 12% less than that of the normal controls; the respective difference of the mean cell size was 5% and that of MCHC 3% lower than normal.
Blood levels of glucose, lactate, pyruvate and total ketone bodies were measured in 16 conscious mothers and their minimally stressed fetuses at 18-21 weeks gestation. Blood samples were taken from the maternal antecubital vein and from the fetal umbilical vein and artery during fetoscopy prior to termination of pregnancy. The mean concentrations of blood glucose, lactate and pyruvate were similar in maternal and fetal venous blood; no significant difference was found between the fetal umbilical artery and vein concentrations. Maternal total blood ketone body levels were significantly higher than fetal levels with no detectable umbilical venous arterial concentration difference. There was a significant inverse relationship between the umbilical artery levels and the umbilical venous-arterial concentration differences for blood glucose and lactate.
Several gastrointestinal hormones appear to play an important developmental role in the newborn, particularly in preterm neonates. Although the cells producing these peptides develop towards the end of the first trimester, fetal secretion of these regulatory peptides has not hitherto been demonstrated. Using samples collected by fetoscopy at 19-21 weeks of gestation we have measured concentrations of several gastrointestinal and pancreatic hormones. Maternal venous and amniotic fluid hormone concentrations were measured simultaneously. Concentrations of the pancreatic hormones, insulin, glucagon and pancreatic polypeptide (PP) were similar in fetal and maternal blood. Gastrin and motilin were present in the fetal circulation but at about 30% (p < 0.05) and 60% (p < 0.01) of the maternal levels, respectively. In contrast, enteroglucagon concentrations were more than twofold higher in the fetal circulation compared with maternal levels (p < 0.05). Concentrations of gastric inhibitory polypeptide (GIP) in fetal blood were higher than levels in maternal blood but not significantly. Concentrations of GIP (p < 0.001) were higher in the amniotic fluid than the fetal circulation. Gastrin and glucagon levels were similar in amniotic fluid and fetal blood. In contrast, PP and motilin were present in amniotic fluid, but at lower concentrations than in fetal blood. Enteroglucagon was not detectable in amniotic fluid. In conclusion, several alimentary hormones are secreted in the fetus at midterm. Since these peptides have trophic, secretory and motor effects on the gut, it is likely that these regulatory peptides are involved in the functional development of the fetal intestine.
The authors report the first successful case of fetal exchange transfusion performed in Rh disease. The patient was a gravida 3, para 1; a first ultrasound guided intra-funicular transfusion was carried out at 28 gestation weeks (Coombs test: 256, Liley's chart: zone III, fetal hemoglobin: 5.7 g/l). One week later a fetal exchange transfusion was decided because of the appearance of ascites, sinusoidal heart rate pattern, and Manning's score at 4. At 29 weeks of gestation an ultrasound-guided umbilical cord puncture was performed with a 16-gauge Tuohy needle, a catheter for epidural analgesia (Perifix) was inserted through the trocar. A total exchange of +126/-96 cm3 of 50% hematocrit (Hct) concentrated and irradiated blood without leukocyte and platelet was performed increasing fetal hemoglobin concentration from 3.9 to 11.9 g/l. A 2,040-gram girl was delivered by cesarean section at 33 gestation weeks with Apgar score of 7/9/9 and she was given 4 total exchange transfusions in the Neonatal Intensive Care Unit. Two years later her development is normal. This new procedure seems easier than fetoscopy to achieve umbilical cord puncture and avoid excess blood volume while exact correction of anemia is possible. With more concentrated blood (70% Hct) the duration of the procedure is shortened.
Despite improvements in surgical techniques, the results of open fetal surgery to correct congenital diaphragmatic hernia have been disappointing. Hysterotomy induces preterm labour and, where there is a large volume of liver in the fetal chest, reduction of the liver into the abdomen induces immediate fetal death. Less invasive techniques, using both open surgery and fetoscopy, are being developed in the hope of reducing fetal demise. These techniques include blocking the trachea, the creation of an artificial gastroschisis and induction of graft tolerance for postnatal lung transplantation.
Telementoring began in the 1950s and is an advanced application of telemedicine that involves the removed guidance of a procedure where the student has no or limited experience. In the past 10 to 15 years, telemedicine has been revisited as a result of the healthcare delivery crisis, budgetary concerns, and the impact of managed care. In recent years, telementoring has had a number of successes which have led to further recent telementoring investigations and developments. Telementoring programs were established because it was impractical for specialized minimally invasive surgeons to proctor fellow surgeons during the adoption phase of new techniques. This catalyzed the establishment of formal telementoring procedural guidelines and networks. Efforts have been made in the remote direction of laparoscopic spermatic vein ligations, renal biopsy, nephrectomy, varicocelectomy, fetoscopy, and ophthalmology. Pilot studies in 2000 have statistically validated that telementoring can be as effective as on-site mentoring. In order to successfully conduct telementoring missions, however, it is important to follow a precise algorithm. If a standardized protocol is followed, it will ensure that telementoring is practiced safely and efficiently.