[Unusual behavior of serum markers in risk evaluation for trisomy 21]

Screening of Down syndrome using serum markers is based on statistic risk determination calculated from the results of markers. An increased risk of fetal Down syndrome is associated with high hCG levels and low AFP levels in maternal serum. In the daily practice, the use of these two markers also leads to observation of different analytical patterns. We reviewed these patterns according to published data and our own experience. Some patterns are well documented (neural tube defects or trisomy 18) some of them remain unexplored. Numerous difficulties are encountered in the clinical use of these markers patterns: lack of consensus for their analytical definition, problems in interpretation, lack of regular dispositions.

[Ascites with "activated" lymphocytes in a case of hydrops fetalis related to a parvovirus B19 infection]

A case of non immunologic hydrops fetalis associated with parvovirus B19 infection is reported. Viral etiology was suspected by the pattern of overstimulated lymphocytes in fetal ascites and confirmed later by identification of parvovirus B19 by PCR. The cytologic finding center helps the precocious diagnosis.

Comparative study of three vaginal markers of the premature rupture of membranes. Insulin like growth factor binding protein 1 diamine-oxidase pH

OBJECTIVE

To assess the diagnostic value of three vaginal markers-insulin-like growth factor binding protein 1 (= IGFBP1), diamine-oxidase (= DAO) and pH-for diagnosis of the premature rupture of membranes.

STUDY

One hundred pregnant women participated in the study. They were divided into three groups: group A (34 cases with intact membranes), group B (35 cases with total rupture of the membranes), group C (31 cases of suspected rupture of the membranes). Each patient underwent three successive tests for each of the three markers. The test order was allocated at random. For pH the reaction is colorimetric, for DAO the reaction is radio-enzymatic and for IGFBP1 the reaction is immuno-chromatographic. All three reactions are qualitative in nature. The parameters studied were conventional statistical parameters (sensitivity = SN, specificity = SP, positive predictive value = PPV and negative predictive value = NPV).

RESULTS

The analysis of the statistics gave the following results in percentages for SN, SP, PPV and NPV respectively; pH: 90.7%, 77.2%, 75%, 91.7%. DAO: 83.7%, 100%, 100%, 89%. IGFBP1: 95.3%, 98.2%, 97.6%, 96.5%.

CONCLUSION

The determination of variations in pH is not satisfactory. IGFBP1 is at least better than DAO with, additionally, advantages of rapidity and simplicity.

Micro-albuminuria analysis and pregnancy. An approach to detect placentary insufficiency?

OBJECTIVE

To assess the value of micro-albuminuria analysis (MA) in predicting clinical complications of placentary insufficiency in women with no known risk factor.

STUDY DESIGN

A blind prospective investigation 20-24 weeks into pregnancy in a nulliparous population with no known risk factor. A reactive strip with a positive threshold value of 10 mg/l is used to detect MA. Judgment criteria concerning the progress of pregnancy are based on blood pressure during the 8th and 9th month of pregnancy and on the 2nd day after delivery, on albuminuria analysis in the 8th and 9th month of pregnancy and by the existence of fetal hypotrophia at birth.

RESULTS

Some 218 patients participated in the investigation. MA was positive in 62 cases (28.4%). Of the 197 births which occurred 54 (27.4%) cases of positive MA, 34 (17.2%) cases presented positive judgment criteria indicating placentary insufficiency. The 21 others pregnancies are in course. MA sensitivity was thus 79.4% and specificity 83.4%. Negative predictive value (NPV) was 95.1% and positive predictive value (PPV) 50%.

CONCLUSION

Our test is a reliable, simple and easily reproducible indicator of micro-albuminuria. In comparison with other tests it gives a good detection rate of a risk group for complication of placentary insufficiency. NPV is excellent, virtually excluding the occurrence of excessive blood pressure or intra-uterine growth retardation. PPV is less good.

Transvaginal ultrasound studies of vascular and morphological changes in uteri exposed to diethylstilbestrol in utero

The aim of this prospective study was to establish complementary data of uteri exposed to diethylstilbestrol (DES) in utero for transvaginal analysis and vascularity changes during the menstrual cycle. A total of 28 women with DES-exposed uteri were compared with 60 non-exposed women. Transvaginal ultrasound and colour Doppler imaging were performed on days 5 and 22 of the menstrual cycle. Uteri were measured on sagittal and transverse scans. Uterine length, width, thickness and uterine cavity length and width were measured. Uterine volume and uterine cavity area were calculated. DES-exposed uterine volume was equal to 31.84 +/- 3.37 cm3. The cavity area of DES-exposed uterus was equal to 35.85 +/- 3.93 cm2. Cervix length of DES-exposed uterus was significantly smaller than that of non-exposed uterus. The uterine artery pulsatility index (PI) of DES-exposed uterus was significantly higher than that of normal uterus. Blood flow remained stable throughout the menstrual cycle. The PI of DES-exposed uterus remained stable during the menstrual cycle, as in non-exposed uterus, and it decreased during the luteal phase. This lack of modification in vascularity of DES-exposed uterus may explain miscarriages and obstetric complications such as intrauterine growth retardation or pre-eclampsia. The data may have implications for the assessment of reproductive status and the design of future studies on disorders of implantation in DES-exposed uterus.

Comparative study of three amniotic fluid markers in premature rupture of membranes: fetal fibronectin, alpha-fetoprotein, diamino-oxydase

BACKGROUND

To study the comparative diagnostic value in premature rupture of membranes (PRM) of three amniotic components: fetal fibronectin (fFN), alphafetoprotein (AFP), diamino-oxydase (DAO).

METHODS

131 pregnant women took part in our prospective study. Three samples were obtained successively for each patient in a random order. Two clinical situations were studied: group A of 68 women with clinical certain PRM and group B of 63 women with a highly unlikely PRM.

RESULTS

fFN is the best marker for diagnosis of PRM (sensitivity of 94% and specificity of 97%). AFP and DAO are complementary: the NPV is greater for AFP (87% against 84%) whereas the PPV is greater for DAO (95% against 86%).

CONCLUSION

Apart from its value in predicting premature labor, vaginal fFN represents a diagnostic test of PRM with good specificity and sensitivity.

Diagnosis of premature rupture of the membranes by the identification of alpha-feto-protein in vaginal secretions

Premature rupture of membranes (PROM) is sometimes difficult to diagnose. This report proposes the use of alpha-feto-protein (AFP) values in vaginal secretions for diagnostic tests. Our investigation took place in two separate phases. The first phase validated the AFP test using an immuno-enzymatic assay method and determined a threshold value from a sample of 167 female patients (Group 1: 133 patients with an extremely low probability of PROM, and Group 2: 54 patients with confirmed PROM). In the second phase the test was applied to a sample of 145 female patients (Group 3) with suspected, but unconfirmed, PROM. Results from alpha-feto-protein (AFP) evaluation were compared with data obtained from clinical, echographic and other tests. The positive/negative threshold adopted was an AFP concentration of 30 micrograms/l. For the two first groups, 1 and 2, sensitivity and specificity was in the 98% to 99% confidence level. For Group 3, sensitivity and specificity results at the 30 micrograms/l threshold value were 94.5% and 95.4% respectively. Quantitative measurement of AFP determined by immuno-enzymatic assay of vaginal secretions with a threshold of 30 micrograms/l is a reliable, simple and rapid diagnostic test. Results obtained are significantly better than the measurement of pH, the determination of prolactin, and more practical than diamino-oxidase (DAO) assays.

[Electrophoresis of cholinesterases of the cerebrospinal fluid in the Guillain-Barré syndrome]

Polyacrylamide gel electrophoresis of cholinesterase from cerebrospinal fluid was performed in 22 patients with Guillain-Barré syndrome. Fifteen of these patients had an abnormal cerebrospinal fluid with emergence of a second electrophoretic migration band corresponding to non-specific cholinesterase. Among 182 patients with a variety of diseases who served as controls, only one presented with this abnormality. From these data the sensitivity and specificity of cerebrospinal fluid cholinesterase electrophoresis were calculated at 68 and 99 percent respectively. The second migration band seems to appear early in the course of the disease and disappears when the patient is cured. Moreover, the occurrence of this band is correlated with the severity of the condition, as shown by a greater number of patients under artificial ventilation and by a longer stay in intensive care unit. Cerebrospinal fluid electrophoresis could be used as a prognosis factor.

[Level of alpha-fetoprotein in maternal serum before and after chorionic villus sampling]

To evaluate incidence and severity of feto-maternal transfusion post-chorionic villus sampling (CVS), maternal serum AFP (MSAFP) were determined for 88 patients before and 15 minutes after CVS. To know whether MSAFP elevation could have clinical implications, a questionnaire was sent to the patients researching if they have had haemorrhages, temperature, spontaneous abortion or premature delivery in the period post CVS. Results of the present study indicate that 44.7% of patients present MSAFP significative elevation (greater than or equal to 8 micrograms/l), a variable elevation (from 8 to 423 micrograms/l). There is no relation between MSAFP elevation and unfavourable events post CVS.

Fetal valproate phenotype is recognisable by mid pregnancy

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[Results of pregnancies characterized by a decrease in the level of alpha-fetoprotein in the maternal blood]

Pregnancy outcome was followed in 123 women showing maternal serum alpha-fetoprotein, less than or equal to 0.50 MOM. In 28 cases AFP was secondarily considered as normal either after ultrasonography and correction of gestation age or after a second sample normal result. In 95 cases AFP level was confirmed lowered; perinatal outcome was normal in 70 cases and abnormal in 25. Among these 25 cases, 3 autosomal trisomies occurred, 2 trisomies 18 and 1 trisomy 21; in the 22 other cases, we observed antepartum risk factors (10 cases with impending premature labor or premature labor, 9 cases with chronic hypertension, 2 cases with Ag HBs hepatitis and 1 case with diabetes).

[Alpha-fetoprotein and trisomy 21]

In 31 affected pregnancies with Down syndrome, the median maternal serum alpha-fetoprotein value was lower than normal, 0.76 MoM, and median amniotic fluid value was quite normal, 0.98 MoM. Selecting an arbitrary cutoff-point of 0.5 MoM, 4.1 percent of normal gestations show values less than 0.5 MoM. Authors discuss problems about screening for fetal Down's syndrome by measuring maternal serum AFP levels.

[Biochemical markers of neural tube closure defects during the second half of pregnancy]

Increasing number of amniocentesis done during the second half of gestation with indication "signe d'appel" made necessary for authors to study amniotic fluid markers in late pregnancy. Normal evolution curve must be established with samples obtained after 20 weeks gestation. Study reveals more false-negative results with AFP than before 20 weeks. AChE remains constantly positive in cases with NTD, band aspect being specific. For other malformations, AChE positivity seems inconstant, with a different aspect. Some normal gestation cases can be associated with faint AChE band.

[Unusual increase in amniotic fluid alpha fetoprotein and trisomy 13]

From 10 observations of trisomy 13, 3 presented an elevated amniotic fluid alpha-fetoprotein level considered as unusual in 2 cases, superior to cut-off level in the other case. Macroscopic examination of the three fetus could not reveal a cause of AFP elevation, neural tube defect or abdominal wall defect. The authors discuss the role of an undetected abnormality such as minor scalp defect with very thin membrane and for one case false-negative result of Kleihauer test.

[Prenatal diagnosis of 4 cases of spina bifida in mothers treated with valproate]

The potential risk of spina bifida (SB) after fetal exposure to Valproate led the authors to apply the following protocol: in case of first trimester exposure to Valproate, prenatal diagnosis is offered and consists of both amniotic fluid examination and fetal ultrasound to detect open spina bifida. In the period 1983 to June, 1986, this program allowed early detection of three cases of SB and pregnancy termination. Another case escaped the programme: neural tube defect was detected lately and the child had to be operated upon. These four cases of SB underline the necessity of prenatal diagnosis with combined use and confrontation of ultrasound examination and biochemical amniotic fluid tests.

[Diagnosis of amniotic embolism by bronchoalveolar lavage]

A broncho-alveolar lavage performed in a patient who developed pulmonary oedema a few hours after a caesarian section, produced foetal squamae which led to the diagnosis of amniotic fluid embolism.

[Contribution of amniocentesis to prenatal screening of neural tube closing defects: evaluation of 10 years of a center's experience]

The authors report retrospective data on analysis of amniotic fluid DFTN markers (AFP and AChE) from 306 cases. Data were obtained from 261 amniocentesis done because there was a recurrence risk of DFTN and from 45 amniocentesis done because an anomaly as DFTN was diagnosed with ultrasonography. Results first show that the risk of recurrence is 3.03% in Rhône-Alpes area. In utero exposure to valproate appears as new indication for amniocentesis, in view of the possible association between Spina-Bifida and prenatal-valproate exposure (1/8 in the study). In contrast to anencephaly, Spina Bifida can be difficult to diagnose with ultrasonography before 20 weeks and require amniocentesis with AFP and AChE study.

[Fetal ascites as a manifestation of infantile sialidosis. Significance of a study of oligosaccharides in amniotic fluid]

Non immune hydramnios and fetal ascite are demonstrated at 31 weeks gestation. There is no familial story. All etiologic investigations (repeated ultrasonographic examinations, amniocentesis) are negative. The delivered girl has a normal development. She presents a congenital ascite and edema. The diagnosis of sialidosis (mucolipidosis type I) is supported by the early finding of vacuolated lymphocytes, the excretion of oligosaccharides in the urine and, finally, the results of the study of alpha-D-neuraminidase fibroblasts and others lysosomal enzymes activities. Oligosaccharides and enzymic studies provide same results in amniotic fluid. Authors point the particular interest of amniotic fluid oligosaccharides study when the etiologic diagnosis of idiopathic fetal ascite or hydrops is to be done.

Transient neutrophil aggregation in a patient with infectious mononucleosis

Transient neutrophil aggregation is reported in a case of infectious mononucleosis. The phenomenon was observed on a blood film patient just before splenic infarction and decreased after splenectomy. The aggregation was so important that differential blood count could not be done. A high serum level of circulating immune complexes was found, and fluorescent spots inside of granulocytes, presumably engulfed immune complexes, could be observed. It is suggested that C activation associated with high immune complexes in infectious mononucleosis is a possible pathogenetic mechanism inducing PMNs aggregation and immune tissue damage.

[Amniotic fluid acetylcholinesterase and prenatal diagnosis of neural tube defects. II. Qualitative test]

The qualitative acetylcholinesterase (AChE) test has been used in conjunction with alpha-fetoprotein (AFP) assay on 255 amniotic fluid samples: 191 from normal pregnancies, 44 from abnormal pregnancies (foetal anomalies or intrauterine death). In all cases of normal amniotic fluid obtained before 25 weeks, gel revealed a single major band of non specific cholinesterase, even in fluids contaminated by maternal of foetal blood, whereas 5 fluids contaminated by foetal blood were false positive on AFP. In 8 normal specimens with clear aspect, obtained after 25 weeks, gel revealed a second (AChE) faint band, inhibited by BW 284 C 51. That result shows the risk of false-positive for samples obtained in late pregnancy. All 20 cases of neural tube defect gave a characteristic AChE band: large and intense band. In 9 cases of abdominal wall defect, 3 presented an AChE faint band, just as 2 cases of atresia and 2 cases of hydronephrosis. Negative AChE results were found un 1 case of congenital nephrosis, 3 cases of hydrocephaly and 1 case of teratoma. The main value of qualitative AChE test seems today in diagnosing neural tube defects with a greater sensibility and in classifying bloody fluids in which the AFP is at or above the cut-off level.

[Acetylcholinesterase of amniotic fluid: application to prenatal diagnosis of neural tube closing defects. I. Quantitative tests]

Acetylcholinesterase (AChE) in amniotic fluid from 165 normal pregnancies and 38 abnormal pregnancies was measured, using a direct assay of AChE activity after inhibition of ChnS with ethopropozine ("Lysivane"). Samples from normal pregnancies of 16-24 weeks gestation have a mean AChE activity of 2,7 U/1 and those obtained at 26-40 weeks have a mean level of 0,6 U/l. Contamination of amniotic fluid with fetal or maternal blood was observed to elevate AChE activity leading to uninterpretable results. Assays in artificial mixtures of amniotic fluid with maternal or fetal blood confirm the risk related to added erythrocyte number. Higher mean AChE activity, 8 U/l, was observed in association with open NTD, but in 7 cases the level was as in normal pregnancy. Elevated levels of AChE were found in association with Turner's syndrome (1) and intra uterine death (2); no increase was observed in 7 cases of omphalocele or laparoschisis, in 6 cases of atresia and 2 cases of hydrocephaly. In practice frequent occurence of bloody samples, specially from abnormal pregnancies, limits application of the test for antenatal open NTD diagnosis. This test appears as and useful preliminary stage providing informations for realization and interpretation of gel electrophoresis of cholinesterases.

[Problems posed by prenatal diagnosis of abdominal wall malformations]

The authors present 6 observations of in utero detected abdominal wall defect : 2 laparoschisis and 4 omphaloceles. In three cases the diagnosis have been done prior week 20, by systematic AFP assay for amniocentesis performed for cytogenetic or metabolic reasons; the pregnancy was terminated. In three other cases, the pregnancy was complicated by hydramnios after week 30; amniocentesis for AFP and echography were performed to detect fetal malformations after associated with hydramnios. The detected abdominal wall anomaly was not alone: two fetus had an abnormal caryotype (trisomy 18), three other presented a polymalformative syndrome, a Beckwith-Wiedemann syndrome was discussed for the last child. The in utero diagnosis of omphalocele or laparoschisis implicates difficulties for genetic counselling, particularly if the diagnosis is done prior week 20. These anomalies can be treated with surgical management, but frequency of associated malformations must be underlined. it is important for genetic counselling to know the family history, the amniotic fluid cells caryotype, and an ultrasound scanning performed to reveal any other malformations.

[Acetylcholinesterase: an additional test for diagnosis of fetal malformations]

From an observation of in utero suspected myelomeningocele, the authors underline interest of pattern of cholinesterases using acrylamide gel electrophoresis. The AChE isoenzyme band appears in some fetal malformations, particularly NTD. This biochemical test is considered as complementary of the AF alpha-fetoprotein assay.

[Ultrasonography and alpha fetoprotein determination: two complementary tests in the prenatal diagnosis of anencephaly]

From an observation, authors underline the interest of two complementary tests: ultrasonography and amniotic fluid AFP determination. About the reported case, the chronology of facts is unusual: ultrasonography led initially to suspect anomaly, then elevated AFP result confirmed the malformation.

[Significance and limits of alpha-fetoprotein levels in the prenatal diagnosis of malformations of the central nervous system]

Amniotic fluid or/and serum alpha-foeto protein (AFP) determination is used as a test-system for screening of neural tube defects. The physiologic basis of this screening are described taking into account the evolution of AFP concentration in foetal and maternal blood, and in amniotic fluid. As for all the biologic screening systems, the acquired experience reveals a lack of sensibility and specificity. First the authors analyse the analytic and biologic problems which have an effect upon sensibility; then, they consider the mechanisms which explain the specificity lack showing itself in some foetal malformations. Practically, interpretation of AFP results requires necessarily familial story and echography results. Taking into consideration the different problems concerning AFP, a programme to utilize the test-system is presented for prenatal diagnosis of malformations of central nervous system.

Alpha-fetoprotein levels in placenta, maternal, and cord blood in normal and pathologic pregnancy

The level of placental alpha-fetoprotein (AFP) in normal pregnancy at term was found to be 5050 +/- ng/g fresh tissue. A significant increase was noted in the toxemic placenta associated with a rise in circulating maternal AFP level and a nonsignificant increase in cord blood. The increase in maternal AFP level in cases of premature delivery before 33 weeks' gestation and postmature delivery after 40 weeks' gestation predicted that maternal AFP measurement throughout the second and third trimester of pregnancy could be clinically established as an index of placental function.

[The antenatal diagnosis before 20 weeks of an omphalocoele and a failure of development of the abdominal wall (author's transl)]

We report 2 cases of malformations occuring in the region of the umbilicus which were diagnosed by amniocenteses before the 20th week of pregnancy (with levels of alphafetoprotein) and echography. Failure of development of the abdominal wall was only diagnosed for certain after the therapeutic abortion had been carried out. The omphalocoele was diagnosed for certain by echography at the 19th week after anencephaly and spina bifida had been eliminated in spite of an abnormally high rise in the level of amniotic fluid alphafetoprotein (100.000 microgram/l). We have not found any similar cases in the literature at this gestational age. These observations prove the value of combining the estimation of alphafetoprotein level in the amniotic fluid when making antenatal diagnoses because of the age of the mother (after the age of 38), with echography specially directed to searching for such apparent morphological abnormalities.

[Copper intra-uterine devices (I.U.D.) and pregnancy: a study of the metabolism of copper and of ceruloplasmin in the mother and in the products of conception (author's transl)]

The authors studied the variations in levels of copper and ceruloplasmin in the mother and in products of conception during the first trimester of pregnancy, during the 4th month of pregnancy and near term, having a series of 12 pregnancies with the copper I.U.D. in position. No change was observed between the levels of copper and ceruloplasmin in comparison with a control series.

Purification of placental alpha-1-foetoprotein

Quantitation of placental alpha-1-foetoprotein was done by the radioimmunoassay technique and gave a mean value of 6060 +/- 22.2 ng/g fresh tissue. The purification process included three methods. (1) Protein precipitation was performed using ammonium sulphate at 50 and 70% saturation. Elution on a Concanavalin A-sepharose column was used to diminish the interference of albumin with alpha-foetoprotein. (2) A coupling immunoadsorption technique using CNBr-activated Sepharose 4-B, antialbumin and antitransferrin, was found to be more reproducible. (3) Counter-immunoelectrophoresis and discontinuous gel electrophoresis gave a 60% yield with a 400-fold purification.

[Ethanol perfusions during threatened premature labor. Special study of oxytocinase activity]

The anti-oxytocic effect of perfusions of ethanol have been studied in 19 cases of threatened premature labour. Ethanol has a muscle-relaxing action on the uterus which was demonstrated in 8 out of the 19 cases. Blood alcohol levels equal at least to 1 gm per litre seem to be necessary to have any chance of success and furthermore action has to be rapid and given in loading doses. There are secondary effects from ethanol perfusions which, the authors consider, considerably limit the use of this product in threatened premature labour. Furthermore, when levels of the ocytocinase effect on the serum was studied in 10 cases before and after transfusing the ethanol, the results showed that there was little likelihood that overactivity of ocytocinase could explain the lowering in the levels of oxytocins brought about by the use of ethanol.

[Iliac crest bone CO2 and CO2/Ca ratio in man during respiratory failure (author's transl)]

The bone is often considered as a slow exchanger and bone sampling from the iliac crest, by needle-biopsy, is a commonly used and atraumatic technique; therefore the significance of the evolution of CO2 stores has been investigated in iliac crest in respiratory failure. Samples are taken before ventilation and on the first, second, and in some cases third days after ventilation. The results show that ageing is to be considered, since the CO2/Ca ratio varies according to the age group (0.84 at 30 years and 1.35 at 60 years). Patients with respiratory failure may be distributed into two main categories: hypoxic patients without hypercapnia, and patients with predominant hypercapnia. Hypercapnic patients may be differentiated from the hypoxic ones, both before assisted ventilation and on account of the dynamic phenomena that come into play during respiratory support in this group of patients. If the equilibrium state (at least five days with rigorously steady gazometry), before assisted ventilation, remains unknown, it is not possible to distribute the patients in one of these two groups. The results' significance is discussed, as well as the possible therapeutic applications.

[Alpha fetoprotein in umbilical cord blood]

Quantitative measurement of alpha-foetoprotein was made on the cord blood of 158 new-born of gestational age ranging between 15 and 43 weeks. The technique used was that of simple radial immunodiffusion of Mancini which made possible the exact measurement of A.F.P. in all the specimens apart from 3. The correlation coefficient between the A.F.P. level in cord blood and gestational age is significant (r equals 0,85 for a risk p equals 0,001). However, the degree of difference at a given point in pregnancy and the difference in levels found in certain cases of twin pregnancies, suggest that factors other than gestational age (certain complications of pregnancy, for example) may influence foetal A,F.P.