[Recommended algorithms of prescription in the diagnosis of iron deficiency and overload]. / Algorithmes de prescription recommandés pour le diagnostic d'un déficit et d'une surcharge en fer.

In view of the recent development of new tests of biochemistry and molecular biology the assessment of iron status should be reconsidered and updated. The French Society of Clinical Biology (SFBC) and the French Society of Hematology (Cellular Hematology Group) recommend algorithms in the diagnosis of iron deficiency and iron overload bearing in mind the best efficiency and health economy. These recommendations are based on the known sensibility and specificity of each test. The analytical requirements for the determination of the tests as well as the clinical and biological signs evoking an iron deficiency or overload are recalled.

Evaluation of the Abbott system in maternal serum screening for Down syndrome: the AxSym analyzer, AFP and hCG reagents and Maciel Prenatal Interpretive Software.

Multi-marker maternal serum screening for Down syndrome in the second trimester is now part of routine care in many centers. Most protocols use a combination of hCG (or its free beta-subunit) and alpha-fetoprotein (AFP) or unconjugated estriol (UE3), or both. Risk calculation is based on these maternal serum marker values combined with maternal age and trisomy 21 maternal age-related risk. Computer programs are therefore necessary. Both technical and statistical efficiency are included in the final risk evaluation. We studied the Abbott system, comprising AxSym analyzer, AFP and hCG kits and Prenatal Interpretive Software (Maciel). Median values were established between 14 and 18 weeks of amenorrhea in a population of 1822 patients and in twin pregnancies in 157 cases. Forty maternal sera from trisomy 21 affected pregnancies were analyzed. Software was evaluated in a population of 429 patients and in 124 cases of trisomy 21. We conclude that this system constitutes an accurate and efficient method of maternal serum screening for Down syndrome.

Insulin-like growth factor binding protein 1 level in amniotic fluid: correlation with birth weight.

Insulin-like growth factor binding protein 1 is the predominant insulin-like growth factor binding protein in amniotic fluid. It is produced by the decidua and by fetal tissues, and it is thought to play an important role in fetal growth. We have measured this protein in 58 samples of amniotic fluid, from 13 to 19 gestational weeks, and found a highly significant negative correlation with fetal weight at birth. We conclude that the level of insulin-like growth factor binding protein 1 in amniotic fluid at midpregnancy is a good marker of fetal growth failure.

[Value of the protein profile in unexplained inflammatory syndromes]. / Intérêt du profil protéique dans les syndromes inflammatoires inexpliqués.

UNLABELLED: The diagnosis of unexplained inflammatory syndromes requires many investigations which are commonly expensive, often invasive and must be repeated several times. A means for physicians to improve the diagnosis procedure would be to have new tests available to select the best diagnosis procedures. In order to test the value of the protein profile (PP) in the case of unexplained inflammatory syndromes, we prospectively studied 95 among 650 patients admitted in our unit for an inflammatory syndrome defined by a C Reactive Protein level > 2 mg/dL and a sedimentation rate > 30 mm, which remained unexplained after a 5 day hospitalization (49 men, 46 women; mean age: 62.9 +/- 12.3 years). PP has been considered as a useful test for the diagnosis in 21 cases (22%) having been definitively established by pathologic examination (42%), radiologic procedures (24%), endoscopy (19%), immunological tests (19%), and serological test (9.5%). The definitive diagnosis was a systemic disease in 12 cases, infection (four cases), malignancy (three cases), amyloidosis (one case) and occult intestinal bleeding (one case). CONCLUSION: Our data indicate that PP is a useful test for the diagnosis of unexplained inflammatory syndromes; its main utility is the disclosure of some specific biochemical syndromes available for better selecting the definitive diagnosis procedures.

Familial ligand-defective apolipoprotein B-100: simultaneous detection of the ARG3500-->GLN and ARG3531-->CYS mutations in a French population.

Familial ligand-defective apolipoprotein B-100 (FDB) is an autosomal dominant disorder leading to plasma LDL cholesterol elevation and coronary artery disease (CAD). Two specific mutations in the APOB gene--R3500Q and R3531C--induce FDB. We report an original method to detect both mutations simultaneously, based upon PCR-mediated, site-directed mutagenesis and double restriction of a unique PCR product. With this method we have investigated the prevalence of these mutations in 1,040 French patients. The R3500Q mutation was found in five probands. Genotypes were determined for 10 APOB polymorphic markers and were consistent with the common European ancestral haplotype previously reported. The only exception was one FDB proband who did not harbor the 48 repeat allele of the 3'HVR. Additionally, the first two R3531C mutations were identified in French probands. Genotypes were consistent with a previously reported haplotype, suggesting that this is another mutation of European ancestry.

Maternal serum human chorionic gonadotropin level at fifteen weeks is a predictor for preeclampsia.

OBJECTIVE: Our purpose was to study the correlation between maternal serum human chorionic gonadotropin levels measured at 15 to 18 weeks of amenorrhea and pregnancy-induced hypertension, preeclampsia, and small-for-gestational-age neonates. STUDY DESIGN: Prospective trisomy 21 human chorionic gonadotropin screening data from 5776 patients were examined in a retrospective investigation of the relationship between human chorionic gonadotropin and pregnancy-induced hypertension (234 cases), preeclampsia (34 cases), and small-for-gestational-age neonates (238 cases). RESULTS: Maternal serum human chorionic gonadotropin (multiples of the median) was higher in the three populations with pathologic disorders. This difference was statistically significant in patients with small-for-gestational-age neonates (p < 0.0163) and preeclampsia (p < 0.0001) but not in those with pregnancy-induced hypertension. In the preeclampsia subgroup, with a cutoff value of 2 multiples of the median, specificity was 32% and sensitivity was 10%; with a cutoff value of 1 multiples of the median, specificity was 100% and sensitivity was 50%. CONCLUSION: High maternal serum human chorionic gonadotropin levels at 15 weeks are related to a risk for preeclampsia. Depending on the human chorionic gonadotropin cutoff value, 32% or 100% of preeclampsia patients would be selected. The usefulness of preventive aspirin treatment from the fifteenth week needs more investigation in a larger multicenter study of preeclampsia.

[Protein profile and iron deficiency: value of the study of the albumin-transferrin couple]. / Profil protéique et carence martiale: intérêt de l'étude du couple albumine-transferrine.

From a clinical standpoint, the search for iron deficiency is based upon serum ferritin. However, serumferritin values may be pathologic in other numerous pathological conditions such as inflammation, liver diseases, malignant hematologic disorders, hemolysis, etc. Proteic profile combines the analyze of proteins variations: protein results are converted in percent of normal values referenced for the technique used. It has been suggested that on the protein profile, an increase in serum transferrin level compared to a normal serum albumin level (DAT: difference albumin-transferrin), appears early in the course of iron deficiency. In order to know the value of a pathologic DAT > or = 28% in the diagnosis of iron deficiency, we prospectively studied 156 patients consecutively hospitalized in an internal medicine department. Iron deficiency was defined by a low serum ferritin level. Diagnosis performance (sensitivity, specificity, positive and negative predictive values) of different biologic markers of iron deficiency (serum iron, saturation of total iron-binding capacity, low mean erythrocyte volume) and DAT was compared to the performance of low serum ferritin values. With the exception of low serum ferritin (which have by definition a specificity and a positive predictive value of 100%), pathologic DAT appeared as the best index of iron deficiency with the highest sensitivity (67.4%), specificity (97.3%), positive predictive value (91.2%), negative predicitive value (87.7%) and diagnosis efficacy (sensitivity x specificity = 0.66). A pathologic DAT associated to a low serum ferritin level increased the diagnosis performance of both tests to 0.72. Diagnosis efficacy of DAT was not changed (0.66) in 83 patients with a confounding factor for serum ferritin analysis (inflammation, liver diseases, malignant hematologic disorders, hemolysis) when diagnosis efficacy of all other tests decreased. There was a negative correlation between serum ferritin level and DAT level (r = 0.55; P < 0.0001). In conclusion, an increase of serum transferrin of more than 28% compared to serum albumin on a proteic profile gives a significant benefit for the diagnosis of iron deficiency. This benefit increases when data of both DAT and serum ferritin are associated.

[Prenatal diagnosis of neural tube defects. Value of electrophoresis of cholinesterases]. / Diagnostic prénatal des défauts de fermeture du tube neural. Intérêt de l'électrophorèse des cholinestérases.

Cholinesterase electrophoresis was performed in 802 amniotic fluids and its value in the detection of neural tube defects was compared with those of ultrasonography and amniotic fluid alpha-foetoprotein levels. Cholinesterase electrophoresis confirmed the ultrasonic diagnosis in 51 cases of neural tube abnormality and made it possible to diagnose neural tube defect in 6 other cases which had remained undetected by ultrasound and by alpha-foetoprotein level measurements. When our technique is used before the 28th week of gestation, false-positive results concern abnormalities which are easily detected by ultrasound (omphalocele, Bonnevie-Ullrich syndrome, sacrococcygeal tumour). We did not observe any false-negative result.

[The concept of protein profile]. / Le concept du profil protéique.

From their own experience of the simultaneous immunonephelometry of eight serum proteins, the authors propose a definition of protein profile from the point of view both of laboratory technique and interpretation. The assay should be performed quickly and the results expressed diagrammatically in normalised values, in such a way that the relative variation in protein levels can be easily visualised. A protein profile should thus comprise a minimum of proteins to be measured, chosen according to protein physiopathology and the type of abnormality under investigation. Interpretation is based on inter-protein correlations that may appear or disappear depending on the underlying physiopathology. This makes it possible to study inter-protein variation and thus avoid the probabilistic "interpretation" of single proteins taken in isolation. From this approach syndromes can be divided into two groups, elementary or complex. The authors provide examples of each, and propose an interpretation model based on this dichotomy.

[Decrease of the 3rd fraction of serum complement. Study in a hospital population of 13000 patients]. / Baisse de la troisième fraction du complément sérique. Etude dans une population hospitalière de 13 000 sujets.

Patients with serum concentrations of C3 lower than 0.40 g/l among 13 000 patients in a general hospital seen over an 18 months period were studied. 95 cases were eligible for study. Diffuse and severe liver disease accounts for 50% of cases. Immunologic diseases represent little more than 10% of cases. The other common causes are severe infections and nutritional deficiencies. Besides the immunological diseases, low C3 serum concentration represents a poor prognosis factor since 55% of patients died during hospitalization.

[Location of an insulinoma by transhepatic phlebography with staged insulin assays (author's transl)]. / Localisation d'un insulinome par phlébographie transhépatique avec dosages étagés de l'insulinémie.

Insulinoma was easily diagnosed in a 73-year-old woman who had organic hypoglycaemia associated with hyperinsulinism, but the tumour could not be located by echotomography and computerized tomography. The state of the patient's arteries precluded arteriography. Pancreatic phlebography was carried out by the portal transhepatic route and blood was collected at different levels for plasma insulin assays. A very high gradient at the pancreatic isthmus indicated the site of the tumour, which was found on surgery to be precisely there and could be enucleated. This technique cannot be used systematically to locate insulinomas, but it is unquestionably helpful when the tumour cannot be located by other methods or when these are contra-indicated.

[Does the insulin-secretion capacity of non-diabetic subjects possess a prognostic value? (author's transl)]. / La capacité d'insulino-sécrétion des sujets non diabétiques possède-t-elle une valeur pronostique?

Twenty-two patients, whose initial oral glucose tolerance test (OGTT) was not diabetic, but who possibly had predisposition for diabetes, underwent iterative OGTT with plasma insulin determination and estimate of insulin-secretion capacity (plasma insulin area/blood glucose area ratio, and insulin-secretion coefficient). With a 30 months mean time interval between the two tests, a highly significant negative correlation was found between insulin-secretion capacity of the first test and blood glucose area of the last one. Glycemic curve of the OGTT was diabetic in 3 cases at the final test. Thus, it seems possible to select subjects most prone to future diabetes with simple parameters estimating insulin-secretion capacity during OGTT.