Patrick Hohlfeld

Prenatal Diagnosis of Congenital Toxoplasmosis with a Polymerase-Chain-Reaction Test on Amniotic Fluid

BACKGROUND Congenital infection with Toxoplasma gondii can produce serious sequelae. However, there is little consensus about screening during pregnancy, and the tests used to establish a prenatal diagnosis of toxoplasmosis are complex and slow. We evaluated a simpler approach that is based on a polymerase-chain-reaction (PCR) test. METHODS Prenatal diagnostic tests, including ultrasonography, amniocentesis, and fetal-blood sampling, were performed in 2632 women with T. gondii infection acquired during pregnancy. In 339 consecutive women, a competitive PCR test for T. gondii was performed on amniotic fluid, and its results were compared with those of conventional diagnostic tests. The PCR test targets the B1 gene of T. gondii, uses an internal control, and can be completed in a day. Positive tests were confirmed by serologic testing of newborns or by autopsy in terminated pregnancies. RESULTS Overall, the risk of fetal infection was 7.4 percent, but it increased sharply with gestational age. Congenital infection was demonstrated in 34 of 339 fetuses by conventional methods, and the PCR test was positive in all 34. In three other fetuses, only the PCR test gave positive results, and follow-up testing confirmed the presence of congenital toxoplasmosis. The PCR test gave one false negative result but no false positive results. The PCR test performed better than conventional parasitologic methods (sensitivity, 97.4 vs. 89.5 percent; negative predictive value, 99.7 vs. 98.7 percent). CONCLUSIONS For the prenatal diagnosis of congenital T. gondii infection, an approach based on a PCR test performed on amniotic fluid is rapid, safe, and accurate.

Fetal toxoplasmosis: outcome of pregnancy and infant follow-up after in utero treatment.

Eighty-nine cases of fetal Toxoplasma infection are reported in women treated with spiramycin during pregnancy. Thirty-four pregnancy terminations were performed (2.7% of the total number of acquired Toxoplasma infections during pregnancy). Fifty-two pregnancies were allowed to proceed (43 being additionally treated with pyrimethamine and sulfonamides), leading to the birth of 54 live infants. After a mean follow-up period of 19 months, 41 infants had evidence of subclinical Toxoplasma infection, 12 had a benign form, and one had severe congenital toxoplasmosis (this infant did not receive the additional treatment during pregnancy). Efficacy of the additional treatment with pyrimethamine and sulfonamides was demonstrated by a significant reduction of severe congenital toxoplasmosis and the relative decrease of the ratio of benign to subclinical forms. We recommend that spiramycin treatment be started as soon as possible once the diagnosis of maternal Toxoplasma infection during pregnancy is proved or strongly suspected, because a prolonged time interval between onset of infection and start of treatment seems to be associated with the presence of severe fetal lesions at the time of prenatal diagnosis.

Tissue engineered fetal skin constructs for paediatric burns

Autologous skin-grafting is the gold standard for treatment of deep second and third degree burns. Available bioengineered skin products also necessitate this two-step surgical procedure. Therefore, we developed fetal skin constructs to improve healing of such degree burns. A bank of fetal skin cells was developed from one organ donation (4 cm2 of skin allowing the preparation of several million three-dimensional skin constructs, 9x12 cm, on native horse collagen). Successive fetal constructs were applied to eight patients at every change of dressing during 1-3 weeks in an outpatient setting. Complete closure was rapid (mean 15.3 days [SD 5.5]) with little hypertrophy of new skin and no retraction seen. This simple technique provided complete treatment without auto-grafting, showing that fetal skin cells might have great potential to treat burns and eventually acute and chronic wounds of other types.

Prenatal diagnosis of congenital cytomegalovirus infection

Objective To assess prospectively the diagnostic reliability and prognostic significance of prenatal diagnosis of cytomegalovirus (CMV) infection. Methods One hundred ten pregnant women (four with twin pregnancies) with a risk of congenital CMV infection were investigated. Prenatal diagnosis was carried out by amniocentesis and fetal blood sampling (n = 75) or amniocentesis alone (n = 35). Serial ultrasonographic examinations were performed from time of referral until pregnancy end. All infected neonates were given long-term follow-up. Autopsy was performed in all cases of termination of pregnancy. Results Nearly 23% (26 of 114) of fetuses were infected and prenatal diagnosis was positive in 20 cases. Sensitivity of prenatal diagnosis was 77% and specificity 100%. In eight cases, parents requested termination of pregnancy on the basis of abnormal ultrasonographic findings and/or biologic abnormalities in fetal blood. In 12 cases, parents decided to proceed with the pregnancy. In this group, one intrauterine and one neonatal death were observed. In one case, prenatal diagnosis revealed an abnormal cerebral sonography and the infant had bilateral hearing loss at birth. In 15 cases (nine positive and six false-negative prenatal diagnoses), no apparent lesion was present at birth, nor did it develop during the follow-up period (mean 31 months). In 88 (77.2%) of 114 infants, no evidence of vertical transmission was found during the pre- or postnatal period. Conclusion Prenatal diagnosis provides the optimal means for both diagnosing fetal infection (amniocentesis) and identifying fetuses at risk of severe sequelae (ultrasound examination, fetal blood sampling), thus allowing proper counseling.

Role of Chlamydia trachomatis in Miscarriage

TOC Summary: Women experiencing miscarriage should be screened for C. trachomatis.

Mycoplasma hominis in mid-trimester amniotic fluid: relation to pregnancy outcome

Abstract Objective: The relationship between detection of Mycoplasma hominis in mid-trimester amniotic fluid and subsequent pregnancy outcome was investigated. Study design: Amniotic fluids from 456 women of European background who underwent a transabdominal amniocentesis at weeks 15–17 of pregnancy were tested for M. hominis by polymerase chain reaction (PCR). The amplicons were hybridized to an internal probe and detected by ELISA. Pregnancy outcomes and clinical data were subsequently obtained. Results: M. hominis were identified in 29 (6.4%) of the amniotic fluids. The rate of preterm labor in women positive for M. hominis (14.3%) was higher than in the negative women (3.3%) (p=0.01). Similarly, a spontaneous preterm birth with intact membranes occurred in 10.7% of the M. hominis-positive women as opposed to only 1.9% of the negative women (p=0.02). The presence of this mycoplasma was not correlated with fetal chromosomal aberrations, intrauterine growth restriction or preeclampsia. Conclusions: Detection of M. hominis in second-trimester amniotic fluids can identify women at increased risk for subsequent preterm labor and delivery.

Screening for gestational diabetes: variation in guidelines.

OBJECTIVE To compare published guidelines concerning screening for gestational diabetes. STUDY DESIGN Systematic search and comparative analysis of published guidelines. Appraisal of guidelines quality. Simulation analysis. RESULTS Ten published guidelines proposed either universal screening (5), selective screening (3) or screening when clinically indicated (2). Variations of testing schedules and blood glucose thresholds were observed. The quality of the published guidelines was low, on average 22 (8-51) percentage points on the assessment scale. These differences would have led to large variations in the number of patients to be screened. CONCLUSIONS Large variations between guidelines have been observed which would translate in large practice variations, if the guidelines were systematically applied. These variations are partially explained by the absence of definite evidence that universal or selective screening for gestational diabetes do more good than harm on infant and maternal health. The methodology of developing guidelines should be more evidence based, systematic and explicit.

Haematological parameters of parvovirus B19 infection in 13 fetuses with hydrops foetalis

Thirteen cases of fetal parvovirus B19 infection with hydrops foetalis are reported. Viral DNA was identified by polymerase chain reaction (PCR) of amniotic fluid sampled between the 19th and the 29th week of gestation. Haematological examination revealed severe anaemia in all cases and thrombocytopenia in 11/13 cases, which was severe in two cases. Six fetuses died in utero; two after intrauterine transfusion. Complete recovery was observed in seven fetuses; five cases were treated by intrauterine transfusions, and in two cases spontaneous recovery occurred. Upon follow‐up, no case of congenital anaemia was observed.

Screening for infectious diseases

IntroductionFetal brain injury is an essential cause of lifelong morbidity. Infection appears as a cause of brain damage. Apart from chorioamnionitis, screening for infectious diseases must be considered in pregnancies with a risk of congenital infection or cases with abnormal cerebral ultrasound findings.DiscussionCongenital infections include most of the major components of the TORCH complex: toxoplasmosis, rubella, cytomegalovirus, herpes, and varicella. Seronegative mothers can develop primary infection, which carries a risk of vertical transmission. The timing of the infection is a critical point, because fetal damage often depends on the gestational age at which acute maternal infection took place and occurs more likely in the first half of pregnancy. Antenatal ultrasound can detect brain abnormalities, like hydrocephalus, periventricular leukomalacia, calcifications or hemorrhage. Maternal serologic tests must be performed to look for an infectious etiology; the most frequent agents are the components of the TORCH complex. But additional serology must include parvovirus B19, HIV, and coxsackieviruses.

Pelvic floor dysfunction 6 years post-anal sphincter tear at the time of vaginal delivery

Introduction and hypothesisThis study aims to estimate fecal, urinary incontinence, and sexual function 6 years after an obstetrical anal sphincter tear.MethodsAmong 13,213 women who had a vaginal delivery of a cephalic singleton at term, 196 women sustained an anal sphincter tear. They were matched to 588 controls. Validated questionnaires grading fecal and urinary incontinence, and sexual dysfunction were completed by the participants.ResultsSevere fecal incontinence was more frequently reported by women who had sustained an anal sphincter tear compared to the controls. Women with an anal sphincter tear had no increased risk of urinary incontinence, but reported significantly more pain, difficulty with vaginal lubrication, and difficulty achieving orgasm compared to the controls. A fetal occiput posterior position during childbirth was an independent risk factor for both severe urinary incontinence and severe sexual dysfunction.ConclusionsFecal incontinence is strongly associated with an anal sphincter tear. A fetal occiput posterior position represents a risk factor for urinary incontinence and sexual dysfunction.