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Summary: In children, caustic ingestion is due to accidents at home and inadequate storage of caustic agents. In emergency, it is useful to remove the soiled clothes, rinse the affected area, and prevent vomiting and feeding. Caustic ingestion (pH<2 or>12) induces burns of the upper gastrointestinal tract requiring esophagogastro-duodenoscopy between H12 and H24. Strong alkalis cause necrosis with liquefaction of the esophagus, penetrating deeply with a high-risk of perforation. Management of these children requires a specialized care center with an intensive care unit, endoscopic equipment, and a surgical team. Esophageal stricture is the main complication; no prophylactic treatment (steroids) is effective. Strictures occur after the 3rd week, and barium swallow should be performed by the end of the 1st month. Stricture are often multiple, long, and tortuous; endoscopic dilatation is difficult with a high-rate of perforation and a low-rate of success. In situ application of mitomycin C or injection of triamcinolone could reduce the recurrence rate of stricture. In recalcitrant or recurrent strictures, it is recommended to perform an esophageal replacement using a colonic interposition or a gastric tube. Endoscopy should also be performed 15–20years after caustic ingestion to screen for early neoplastic lesions. Prevention is very important for avoiding caustic ingestions. Information and education should be given specifically to the parents of toddlers; caustic products should be stored out of reach of children and they should not be kept with food. [ABSTRACT FROM AUTHOR]

Steroid hormone measurement, first developed with radioimmunoassay, is now becoming easier with the use of automated platforms of immunoassay. However, some hormones remain uneasily detectable because of their low blood concentration, their structural homology or the presence of interferences. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) can be considered as an alternative to immunoassays. This approach allows the simultaneous determination of several parameters thanks to its selectivity led by the detector mass spectrometer and the separate dimension of chromatography liquid. In addition, recourse to UHPLC (ultra high performance liquid chromatography) allows improving selectivity and sensitivity while limiting the samples volumes. The "ready-to-use" kits are now available and added to the "homemade" techniques developed by laboratories, thus giving opportunity for measurement of a wide steroid panel with only one sample. Finally, mass spectrometry methods, including a prior extraction step, allow the use of varied biological fluids (blood, urine, saliva…). Also, several clinical indications could gain from mass spectrometry, especially when hormone levels are low, when several steroids have to be identified, when the sample volume is low. However, this technology represents an important financial investment and in-depth staff training. In addition, some steroids are not easily quantifiable by mass spectrometry. It is likely by immunoassay and mass spectrometry, well-matched technologies, that we could answer the best to clinical questions about steroids.

1.) Total renin, active renin, prorenin, angiotensin II, estradiol and progesterone were measured in maternal, placental and fetal blood and in trophoblastic and uterine tissues of the guinea pig. Furthermore, membrane angiotensin II receptors were measured in trophoblastic tissues. 2.) Blood and tissue concentrations of total renin, active renin, angiotensin II and steroids are shown to increase with gestational age. At the full term of pregnancy (70th post-coital day), tissue concentrations of total renin in chorion (23,900 +/- 2,752 ng/g of tissue/h), maternal placenta (14,210 +/- 1,131), fetal placenta (12,475 +/- 927) and uterus (7,677 +/- 798) are 100 time higher than those observed in placental, fetal and maternal blood. Distribution of blood and tissue prorenin (inactive renin) is similar to that found for total renin. Active renin/Total renin ratio reaches 1% in uterine, placental and chorion tissues and 9.3 +/- 1.0% in maternal, placental and fetal blood. 3.) Angiotensin II levels in systemic maternal blood (690 +/- 99 pg/ml) and in uterine blood (467 +/- 84) are higher than those found in placental blood (266 +/- 39) and in different trophoblastic tissues (between 200 and 400 pg/g). Angiotensin II receptor concentrations are highest in chorion. 4.) Regarding the steroid hormones, it is noted that placental and maternal blood contain more progesterone than trophoblastic tissues. The highest concentrations of estradiol are found in chorion tissue and uterine blood. 5.) A positive correlation is observed between angiotensin II and estradiol in uterine blood (r = 0.69, P less than 0.01) and in chorion (r = 0.71, P less than 0.01). These findings indicate that angiotensin II and estradiol could, by their interactions, play an important role in the physiology of pregnancy.

The immunochemical methods take a preponderant place in the measurement of gonadotropins and ovarian steroids. If the sandwich methods for the ELISA type are almost exclusively used for peptide hormones, the measurement of steroid hormones are necessarily performed by a competition technique. The relatively easy preparation of polyclonal and monoclonal anti-gonadotropin antibodies leads to antibodies with a good specificity for these hormones whereas the anti-steroid, specially monoclonal antibodies, are much more difficult to obtain. The different labeling possibilities used in the detection of the antigen-antibody complex, the quality of existing standards and the immunoassay's reliability are successfully discussed.

The sensitivity of a radioimmunoassay depends on the intrinsic association constant of the interaction between ligand and antibody. Its specificity depends on the position of the chain which forms the link with the antigen. Thus, an antibody specific of estradiol has been obtained by coupling estradiol to albumin via a chain at position 7. For synthetic steroids the structure of which is sufficiency different from that of natural hormones, the requirements for a sensitive assay method not involving chromatography are simply maximum affinity and positioning of the couple at a site which does not undergo metabolic attack. These criteria were used to develop assays for R 2858 and R 2453 which obviate the need to administer radioactive product in clinical pharmacology. Cross-reaction with structural analogs may be used to assay competitors. Thus, R 2323 antibody, highly specific for endogenous steroids, may be used to assay other trienes such as R 1697 (trenbolone) and R 2010 (norgestrienone).

Biological diagnostic of hormonedependency of breast tumors is important for the choice of treatment. Modifications of the metabolism of steroids, oestrogens, androgens, and glucocorticoids allowed a first approach. More recently, investigations have been made on breast tissue receptors for hormones that are involved in the growth of the normal gland. It is actually suggested that one could predict the hormonedependency of a tumor when it contains both receptors for oestradiol and progesterone.

At the ultrastructural level, steroids and their receptors can be detected into their target cells by immunocytochemistry done on sections of anterior pituitary obtained by cryoultramicrotomy. An antigenic determinant is thus shown on fixed and frozen tissue with a monoclonal or polyclonal antibody. Tissue preparation is a compromise between preservation of ultrastructural features and the availability of the antigen. Specificity requires several controls knowledge of crossreaction of the anti-steroid or anti-receptor serum, immunological and biochemical analysis of the antigen, a check of the immunocytochemical reaction itself, specific absorbtion tests, modification to the immunocytochemical reaction in various experimental conditions. Specificity is also modulated by the dilution of the anti-steroid or anti-receptor serum as well as other experimental and physiological variations. Finally a hormone detected in its target cell may not be bound to its specific binding sites. Specific binding is characterized by: tissue and cell specificity, limited number or sites, hormonal specificity and a high affinity. Only thus is it possible to localise by immunocytochemistry the receptor or the hormone bound to its binding site.

A test is described for the evaluation of hormone sensitivity of endometrial cancer in vivo. The concentrations of progesterone and estradiol receptors, and the activities of ornithine-decarboxylase and 17 beta-hydroxysteroid oxido-reductase enzymes have been measured in the tumor, before and after administration of the anti-estrogen tamoxifen. The responses observed, in particular the increase of progesterone receptor, could allow a more rational approach to hormonal therapy of endometrial cancer.

The use and limitations of steroid assay in saliva are presented and discussed. Salivary cortisol was well correlated with unbound cortisol plasma, the only biological active fraction of total cortisol. Assay of salivary cortisol is particularly useful in patients taking oral contraceptives or during pregnancy. Indeed, in these patients, because of the marked increase in plasma cortisol binding globulin concentration (from 41 to 100 mg% or more), plasma total cortisol concentration increases from 18 +/- 4 micrograms% to 40 +/- 10 micrograms% whereas plasma unbound cortisol usually remains within the normal range. During the menstrual cycle, salivary progesterone rises from 5.4 +/- 1.8 to 15.1 +/- 3.6 ng%. As it is well correlated with plasma unbound progesterone concentration, salivary progesterone may be considered as a convenient and reliable index of luteal function. Because of its very low concentration, salivary estradiol is difficult to assay with routinely available techniques and, at present, is of limited interest for clinical investigation.

The authors present a reliable and sensitive estimation of progesterone using a conjugate progesterone IIalpha-hémimaleate-beta galactosidase to identify the immunological reaction, the antibodies being obtained from the rabbit by means of a progesterone 11alpha-hemisuccinate bovine serum albumin. The free and bound fractions are separated by addition of rabbit antigamma globulin antibodies bound on glass beads by glutaraldehyde. This method is applied to estimations of cortisol and oestrone.