Non-reproductive Effects of Anovulation: Bone Metabolism in the Luteal Phase of Premenopausal Women Differs between Ovulatory and Anovulatory Cycles.

Introduction: Several authors have linked subclinical ovulatory disturbances in normal length menstrual cycles to premenopausal fracture risk and bone changes. This study systematically examined the influence of ovulation and anovulation on the bone metabolism of premenopausal women. Participants and Methods: In 176 cycles in healthy premenopausal women, FSH, 17ß-estradiol (E2) and progesterone (P4) as well as bone alkalic phosphatase (BAP), pyridinoline (PYD) and C-terminal crosslinks (CTX) were measured during the follicular and during the luteal phase. The probability and timing of ovulation was self-assessed by a monitoring device. In addition, bone density of the lumbar spine was measured by quantitative computed tomography (QCT) at baseline and at the end of the study. Analysis was restricted to blood samples taken more than three days before the following menstruation. Results: 118 cycles out of the 176 collected cycles were complete with blood samples taken within the correct time interval. Of these, 56.8 % were ovulatory by two criteria (ovulation symbol shown on the monitor display and LP progesterone > 6 ng/ml), 33.1 % were possibly ovulatory by one criterion (ovulation symbol shown on the monitor display or LP progesterone > 6 ng/ml), and 10.2 % were anovulatory by both criteria). Ovulation in the previous cycle and in the same cycle did not significantly influence the mean absolute concentrations of the bone markers. However, bone formation (BAP) was higher in the luteal phase of ovulatory cycles than in anovulatory cycles (n. s.) and the relative changes within one cycle were significantly different for bone resorption (CTX) during ovulatory vs. anovulatory cycles (p < 0.01). In 68 pairs of cycles following each other directly, both ovulation in the previous cycle and ovulation in the present cycle influenced CTX, but not the differences of other bone markers. Conclusion: Ovulatory cycles reduce bone resorption in their luteal phase and that of the following cycle. The interaction between ovulation and bone metabolism is complex. Since anovulation may occur in low estrogen states such as pre-anorexic dietary restraint, as well as with high estrogenic circumstances e.g. from functional perimenopausal ovarian cysts, the association with bone changes has been variable in the literature. Accumulating physiological and clinical evidence however point towards a role for ovulation in enhancing bone formation and limiting bone resorption.

Bone loss in premenopausal, perimenopausal and postmenopausal women: results of a prospective observational study over 9 years.

INTRODUCTION: Few longitudinal data about rates of bone loss in women in midlife exist. Fewer still with their reproductive states having been carefully assessed and sequentially followed-up. METHODS: Complete data from 50 women younger than 60 years (mean age at baseline 48.3 ± 5.4 years) were prospectively collected over 9 years. This was done by standardized interviews, measurement of endocrinological parameters as well as bone markers and repeated bone mineral density (BMD) measurements using quantitative computer tomography (QCT). Women were classified in three groups according to their reproductive characteristics over 9 years. RESULTS: Significant BMD loss was found in women going through the menopausal transition. In perimenopause, there was a correlation (multiple regression results, r = -0.396 and r = -0.527) between accelerated bone density loss and increased gonadotropin levels (follicle stimulating hormone, luteinizing hormone). Although significantly higher levels of bone markers (osteocalcin, bone-specific alkaline phosphatase, c-terminal telopeptide cross-linked collagen type I) were measured in postmenopause, the greatest increase in these markers was seen during the menopausal transition. No individual marker's increase, however, was predictive for perimenopausal bone density loss. The major risk factors for rapid bone loss were a lower initial body weight (< 57 kg), a body mass index < 20 kg/m(2) as well as a positive family history of fragility fractures. CONCLUSIONS: Women in the menopausal transition lose trabecular bone at a rapid rate despite intermittently high and usually normal estrogen levels. This is the only prospective study to date that documents trabecular bone changes in women through the entire perimenopause, which may last up to 10 years.

Autoantibodies to double-stranded DNA--intermethod comparison between four commercial immunoassays and a research biosensor-based device.

Patients with systemic lupus erythematosus (SLE) often develop a wide variety of serological manifestations including the presence of antibodies to double-stranded DNA (anti-dsDNA). Positivity for anti-dsDNA constitutes one of the laboratory criteria for the diagnosis of SLE and is therefore clinically relevant. We analyzed the diagnostic accuracies of four commercial anti-dsDNA immunoassays and compared the results with a recently established surface plasmon resonance (SPR) biosensor chip with covalently chip-immobilized dsDNA. The anti-dsDNA measurements were performed retrospectively in 50 patients with clinically proven SLE, 39 patients with other autoimmunopathies and 20 healthy controls. Data were evaluated by Receiver-Operator Characteristic (ROC) analysis, with special regard to SLE patients suffering from lupus nephritis. The ROC analyses for the four immunoassays and the SPR biosensor resulted in the following area-under-the-curve (AUC) and diagnostic efficiency (DE) values in descending order: Bindazyme AUC, 0.89; DE, 0.88; ELiA AUC, 0.89; DE, 0.86; SPR biosensor AUC, 0.82; DE, 0.80; Farrzyme AUC, 0.77; DE, 0.77; Farr AUC, 0.77; DE, 0.70. When considering the 22 nephritis SLE patients the following AUC were observed: Bindazyme 0.98; EliA 0.95; SPR biosensor 0.93; Farr 0.89; Farrzyme 0.88. Although various methodologies for the determination of anti-dsDNA were compared, the overall diagnostic accuracy was found satisfactory in all immunoassays. Best data were found for the Bindazyme assay. We referenced the measurements to our in-house SPR biosensor device which showed good AUC and DE values. When optimized, this technique, allowing to monitor antigen/ antibody interactions in real-time, may add a new analytical quality to the existing methods, potentially beneficial in diagnosis and clinical monitoring of SLE.

[Efficient and rational laboratory diagnostics in otolaryngology]. / Rationelle und rationale Laboratoriumsdiagnostik in der Hals-Nasen-Ohren-Heilkunde.

This article describes the value of laboratory diagnostic procedures in the diagnostic arsenal of otolaryngologists. The rational and therefore the rationale of the application of laboratory medical methods are critically evaluated. In the era of diagnosis-related groups a high value is placed on a rational laboratory diagnostic, in the sense of a cost-oriented medicine, so that the laboratory diagnostic procedure is always carried out in stages, just as in other diagnostic procedures. The possibilities of clinical chemistry, separated into the theme blocks "clinical chemical basic diagnostics", "haematological parameters", "coagulation investigations" and "immunological diagnostics" are demonstrated based on examples. These are aimed at the needs of otolaryngologists, in that the emphasis in each theme block is centred on the indications and evaluation of the individual laboratory investigation.

[Transport of blood gas samples: is the pneumatic tube system safe?]. / Transport von Blutgasproben: Ist die Rohrpost sicher?

BACKGROUND: Transport of blood gas samples via a pneumatic tube system and subsequent analysis in the central laboratory can reduce costs and errors compared to on-site testing in the operating theatre or the intensive care unit. In this study, a modern pneumatic tube transport system was tested for its usability for this purpose. METHODS: A total of 4 consecutive blood gas samples were obtained intraoperatively from 54 different patients and sent to the central laboratory. Of these, 3 samples were transferred using the pneumatic tube system but by different methods and 1 sample was transported personally which served as a reference. The results of sample analysis concerning blood gases, electrolytes and haemoglobin were compared and examined for differences. RESULTS: No statistically significant differences could be determined between the different modes of transportation. CONCLUSION: Transport of samples for blood gas analysis via a modern pneumatic tube system is safe when samples are correctly prepared.

Influence of pattern of menopausal transition on the amount of trabecular bone loss. Results from a 6-year prospective longitudinal study.

INTRODUCTION: Bone density is lower in postmenopausal than in premenopausal women. Recent findings have suggested that accelerated bone loss already begins before menopause. Despite numerous cross-sectional studies on menopause-related bone density, longitudinal data on perimenopausal bone density changes are scarce. This study sought to characterize the dynamics of changes leading to postmenopausal osteopenia and to possibly find the time point at which accelerated bone loss begins. METHODS: We prospectively followed 34 pre-, peri- and early postmenopausal women without prior external hormone use, measuring their lumbar spine trabecular bone density with quantitative computer tomography at 0, 2 and 6 years. The analysis of the changes over time was done in a tri-parted fashion, since menopausal status changed variably for individual subjects: we grouped the participants according to their currently valid menopausal classification for prospective (baseline classification), interim (2 years) and retrospective (6-year classification) analysis. RESULTS: Six different patterns of menopausal transition were identified in our sample. Bone loss in the groups not reaching postmenopause during 6 years of observation was >50% of the maximum bone loss observed during the study period. Invariably for all analyses, the perimenopausal phase with estrogen levels still adequate was associated with the greatest reduction of trabecular bone mineral density, reaching 6.3% loss annually in the lumbar spine. By comparison, the average rate of loss was slower in the early postmenopause; total bone loss differed by pattern of menopausal transition (one-way ANOVA p<0.05). CONCLUSION: The presented data for the first time show the perimenopausal course of trabecular bone loss (as measured by QCT of the lumbar spine). Acceleration of bone loss during perimenopause reached half-maximal values of the total bone loss measured around menopause, despite adequate serum estradiol levels.

[Bone metabolism, bone density and estrogen levels in perimenopause: a prospective 2-year-study]. / Knochenstoffwechsel, Knochendichte und Ostrogenspiegel in der Perimenopause: eine prospektive 2-Jahres-Untersuchung.

Bone metabolism and trabecular bone density were studied prospectively in 69 pre-, peri- and early postmenopausal women. Markers of bone resorption (OC = osteocalcin, BAP = bonespecific alkalic phosphatase) and bone formation (PYD = pyridinolin, DPD = desoxypyridnolin, NTX = N-terminal telopeptide crosslinked collagen type I, CTX = C-terminal telopeptide crosslinked collagen type I) in serum and urine were followed over a course of two years with five points of examination (0, 3, 6, 12 and 24 months). Bone density was measured at 0 and 24 months. The results of 40 hormonally untreated women who completed all examinations were compared regarding menopausal status and changes over the 2-year-period. While baseline tracecular bone density was lowest in early postmenoapusal women, perimenopausal women showed greatest bone loss (- 10,6 %) during the two year study period. Bone metabolism markers were highest in the postmenopausal group. Perimenopause was associated with a gradual rise in OC, PYD and CTX. Perimenopausal women showed the highest serum estradiol at 0 and 12 months with values exceeding those of premenopausal women. Whether the increased perimenopausal bone loss could be related to the increase in anovulatory cycles during the perimenopausal transition is subject to ongoing investigation.

Induction of a T helper cell response against the tumor-associated antigen HER2 using monocyte-derived dendritic cells.

Tumor-reactive CD4(+) T helper (Th) cells play a criticalrole in antitumor immunity, due to their ability to induceCD8(+) T cell-mediated cytotoxic activity and humoralresponse. This study focuses on the in vitro generationand expansion of Th cells specific for the tumor-associatedantigen ;human epidermal growth factor receptor-2' (HER2). Aprotocol for efficient HER2 presentation was developed usingautologous monocyte-derived dendritic cells (DC) as antigenpresenting cells (APC) and purified HER2 protein as antigensource. Our data suggest that DC pulsed with recombinantprotein of the extracellular domain (ECD) of HER2 (ECD/HER2)induce an ECD/HER2-specific Th cell response. This finding mayfacilitate the development of immunotherapy regimens withoutrequiring defined immunogenic epitopes of the antigen.

Immunosensors--principles and applications to clinical chemistry.

INTRODUCTION: Immunosensors are affinity ligand-based biosensor solid-state devices in which the immunochemical reaction is coupled to a transducer. The fundamental basis of all immunosensors is the specificity of the molecular recognition of antigens by antibodies to form a stable complex. This is similar to the immunoassay methodology. Immunosensors can be categorized based on the detection principle applied. The main developments are electrochemical, optical, and microgravimetric immunosensors. In contrast to immunoassay, modern transducer technology enables the label-free detection and quantification of the immune complex. METHODS: The analysis of trace substances in environmental science, pharmaceutical and food industries is a challenge since many of these applications demand a continuous monitoring mode. The use of immunosensors in these applications is most appropriate. Similarly, a series of clinical problems may be solved by continuous monitoring of certain analytes. CONCLUSIONS: Clinical chemists should take advantage of immunosensors in clinical diagnostics. There are many recent developments in the immunosensor field which have potential impacts. The future role of this technique in intralaboratory, as well as bedside testing, will become even more important as the clinical laboratory is faced with increasing pressure to contain costs.

Sensitive chemiluminescence immunoassay for the determination of rat serum alpha1-acid glycoprotein.

We present the establishment of a sensitive immunoassay for the determination of alpha1-acid glycoprotein (orosomucoid, AGP) in rat serum. The assay is based upon antigen capture by surface-immobilized specific polyclonal rabbit anti-AGP antibodies with biotinylated rat AGP (rAGP) as the tracer, and formatted as competitive enzyme immunoassay. Signaling is performed by streptavidin-conjugated horseradish peroxidase. Enzyme activity is quantified by an enhanced chemiluminometric method, allowing the sensitive detection of rAGP serum levels in small sample volumes.

Concepts for the syntheses of biotinylated steroids. Part II: 17beta-estradiol derivatives as immunochemical probes.

Biotinylated 17beta-estradiol (E2) derivatives are helpful probes for a better understanding of biospecific E2 interactions with steroid-binding proteins such as the estrogen receptor and anti-steroid antibodies. We describe synthetic strategies for the biotinylation of E2 toward the 3, 6alpha, and 7alpha positions using biotinyl-N-hydroxysuccinimide esters with different spacers, varying in structure and chain length. Key reaction for biotinylation at the 3 position is the regioselective ether formation of the phenolate E2 anion with a linker mesylate without protecting the 17beta-hydroxyl group. The 6alpha position is accessible via a 3,17beta protected 6alpha-hydroxy E2, prepared by stereospecific sodium borohydride reduction of 6-oxo E2. Direct cyanoethylation of the alcohol followed by reduction to the amine allows the biotinylation to 6alpha-O-coupled cyanoethyloxy linker E2 derivatives. Alternatively, 6alpha-O-coupled cyanoalkyloxy polyether linker E2 probes are obtained by a Williamson ether synthesis of the alcohol precursor with omega-t-butyl-dimethylsilyloxy-5-oxa-nonylmesylate. Cyanoethylation of the desilylated compound and further reduction of the nitrile led to the terminal amine. Reductive amination of the 3, 17beta acetylated 6-oxo E2 compound with 6-cyanoethyloxyhexyl ammonium acetate yields in a mixture of 6alpha/beta-N-alkylated E2 nitriles. The epimers are separated by reversed-phase HPLC and the 6alpha-compound subsequently reduced to the terminal amine. The 7alpha-biotinylated E2 compound is derived from 7alpha-(11'-undecyl-N-methyl-N-butylamide) E2, which is already known from literature. Subsequently, the 3 and 17beta positions are protected, and the amide is reduced to the 7alpha-(11'-undecanol) compound. Further cyanoethylation and reduction led to the 11'-amino-ethyloxyundecyl E2. Using (1)H NMR analysis, it could be shown that the biotin moiety of the biotinylated 6alpha- and 7alpha-E2 derivatives has an axial position which results in a vertical orientation of the substituent toward the alpha-face of the planar tetracyclic backbone. Thus, a negligible alteration of the original structure of the upper beta-face offers the feasibility of applying the 6alpha- and 7alpha-derivatives as optimal tracers in competitive immunoassays.

Clinical value of cystatin C determination.

It has been reported that cystatin C (cys-C) is elevated in patients with malignant disease. In order to investigate whether this phenomenon is linked to or independent of renal function, and at the same time examine the role of this marker in other pathological situations, cys-C concentrations were compared with 24-h creatinine clearance values in three groups of patients; the first group were undergoing treatment for malignant disease, the second group were renal transplant patients and the third randomly taken from patients for whom a routine creatinine clearance had been requested. Several patients with malignant disease had high cys-C levels without any correspondence to creatinine clearance values. Additionally, although cys-C shows a high sensitivity for detecting impaired glomerular function in renal transplant patients, the specificity was very low, with little discrimination being observed between patients with normal and pathological creatinine clearance levels. In other patients both the sensitivity and specificity of cys-C could be shown to be very good. Thus although cys-C can generally be recommended as a marker of the glomerular filtration rate, there are some patients for whom the clinical relevance is unclear.

Biotinylated steroid derivatives as ligands for biospecific interaction analysis with monoclonal antibodies using immunosensor devices.

Systematic ligand-binding studies of the biospecific interaction between steroids and antisteroid antibodies can be performed in real time using biosensor techniques. In this study, quartz crystal microbalance (QCM) and surface plasmon resonance (SPR) biosensor systems were applied. Different biotinylated testosterone (T) and 17beta-estradiol (E2) derivatives were preincubated with streptavidin and immobilized on the sensor surfaces. We obtained low matrix densities of antigen enabling the investigation of the binding kinetics and position specificities of various anti-E2 and anti-T monoclonal antibodies (mAbs) to these steroidal compounds. The highest immunoreactivity of anti-E2 and anti-T mAbs is not necessarily for the specific modified steroid that was used as a protein-coupled hapten for immunization. The kinetic data confirm that both 3- and 19-specific anti-T mAbs do not discriminate between the 3- and 19-biotinylated T derivatives, whereas the 7alpha-biotinylated T probe showed no affinity to these two anti-T mAbs. In the case of the 3-specific anti-E2 mAb, comparable interaction data were found for 3- and 6alpha-biotinylated E2 compounds. The 6-specific anti-E2 mAb showed comparable ligand binding, but a significant higher dissociation rate to the position-specific antigen. The QCM and SPR results correspond well to the data from cross-reactivity studies in solution as well as to enzyme immunoassay equilibrium measurements.

Changes in collagen I and collagen III metabolism in patients with generalized atopic eczema undergoing medium-dose ultraviolet A1 phototherapy.

Fourteen patients suffering from acute, exacerbated atopic eczema were screened for changes in collagen I and collagen III metabolism in serum (n = 11), urine (n = 11) and skin biopsies (n = 9) before and after medium-dose ultraviolet (UV) A1 phototherapy (15 exposures of 50 J/cm2 over a 3-week period, total dose 750 J/cm2). Mature collagen I and, to a lesser extent, mature collagen III were found to be decreased after the therapy in skin samples from the irradiated patients. As markers of collagen I degradation, the cross-links pyridoline and deoxypyridoline were analysed in urine using high-performance liquid chromatography. Both cross-links were found to be mildly increased after UVA1 phototherapy, without reaching statistical significance. As markers of de novo collagen synthesis we screened for the procollagen I-carboxyterminal peptide (PICP) and procollagen III-aminoterminal peptide (PIIINP) levels in serum and skin. The ratio of PICP to PIIINP in serum dropped significantly after the UVA1 phototherapy, suggesting a different impact of UVA1 on the two collagens. These findings were paralleled by a diminished ratio of PICP to PIIINP in tissue samples. Staining for matrix metalloproteinase 1 (MMP-1) and its specific counterpart, tissue inhibitor of MMP-1 (TIMP-1), showed slight increases for both proteins by therapeutic UVA1; this was also seen in serum for TIMP-1 but not MMP-1. In our study, high-energy UVA1 doses induced changes of the skin collagens in patients with atopic eczema which are measurable by their metabolites in serum and urine.

Concepts for the syntheses of biotinylated steroids. Part I: testosterone derivatives as immunochemical probes.

We describe synthetic strategies for the biotinylation of testosterone (T) at positions 3, 7alpha, 17alpha, and 19. These T probes are able to mimic ligand binding and may provide for a better understanding of the biospecific interaction with steroid-binding proteins such as the androgen receptor, anti-steroid antibodies, or steroid-binding serum globulins. For the 7alpha- and 17alpha-derivatives, biotinyl-N-hydroxy-succinimide esters with different types of spacer chains were used. The 3-biotin hydrazone derivative was produced using N-(epsilon-biotinyl)-caproyl hydrazide, whereas for the 19-biotinylation, a biotinyl-1-N-diamino-3, 6-dioxaoctane-amide was applied. Key reaction for the biotinylation at position 3 is the oximation of the 3-oxo function. The 17alpha-position is accessible by the reaction of the 3-protected 4-androsten-17-epoxide with oxygen in the beta-position, followed by nucleophilic ring opening with cyanide which provides the 17alpha-cyanomethyl derivative. The key step is the regioselective ketal protection of the 3-oxo function of androst-4-ene-3,17-dione using a stannoxane catalyst. An alternative pathway for the insertion of biotin at the 19-position was established by the synthesis of 17beta-hydroxy-androst-4-en-3-one-19-yl carboxymethyl ether. After activation by the carbodiimide method, the compound reacts with aminoterminal biotin derivatives. The copper(I)-catalyzed 1,6 Michael addition of 17-acetoxy-6,7-dehydro-T leads to 7alpha-derivatives by use of omega-silyl protected hydroxylalkyl-modified Grignard reagents. A functional group interconversion using the Staudinger reaction transforms the azide function into a primary omega-amino group. The absolute configurations of the different biotinylated derivatives were investigated by (1)H NMR studies. For the 7alpha-biotinylated T series, additionally, an X-ray analysis proved the axial position of the spacer group. This results in a vertical orientation of the biotin moiety toward the alpha-face of the planar tetracyclic backbone. Thus, a negligible alteration of the original structure of the upper beta-face offers the feasibility of applying the 7alpha-derivatives as optimal immunochemical tracers in competitive immunoassays. Biotinylated T derivatives should be also suitable for ligand-binding studies to the androgen receptor or to sex hormone-binding globulin.

[Clinical significance of allergic reactions in glucocorticoid therapy]. / Klinische Bedeutung allergischer Reaktionen bei Glukokortikoidbehandlung.

BACKGROUND: Glucocorticoids are widely used in medicine. Within the last few years, however, patients have become very suspicious of corticoids. The attending physicians frequently has to use a great deal of persuasion prior to applying this very effective and often indispensable group of medication. PATIENTS: We report on four patients who developed allergic reactions (i.e. erythema in face and on body, itching, flushing, drop in blood pressure, respiratory distress, cold sweats, etc.) immediately after intravenous administration of prednisolone-21 hydrogen succinate (Solu-Decortin H, SDH). RESULTS: Three out of four patients had a positive reaction to an intracutaneous test with SDH, but no reaction to the additive sodium succinate. The prick test was negative in all patients. No specific IgE antibodies were detected in the serum of these patients. However allergic reaction to SDH must be presumed in at least three cases as it is difficult to detect glucocorticoid antibodies in serum and standardizes techniques are lacking. One female patient had a cross-reaction to prednisolon and dexamethasone. A renewed application of SDH was tolerated well by all patients when H1- and H2-receptors were blocked and calcium was administered to stabilize membranes. CONCLUSIONS: Allergic reactions after glucocorticosteroid therapy are only occasionally mentioned in literature, appear more often when the agent is applied topically, and may lead to dangerous complications in patients if administered intravenously. Therefore, when allergic reactions result from glucocorticoid therapy (immediate reactions should be suspect), corticosteroid allergy should be considered as a differential diagnosis.

Solid-phase synthesis, isolation and analysis of a mouse protein, the macrophage migration inhibitory factor.

Murine macrophage migration inhibitory factor (mMIF) is an Mr 12,500 protein composed of all natural amino acid residues. Using the fluorenylmethoxycarbonyl chemistry for solid-phase peptide synthesis (SPPS) under special conditions, a stepwise approach was very successful leading to a crude product in unexpected high purity. After RP-HPLC isolation, a little mass difference of -12 u was determined for the received protein by matrix-assisted laser desorption ionization MS and ion spray MS and the failure sequence [Ser15]-mMIF identified by Edman degradation. The total solid-phase synthesis was repeated in the stepwise manner under the same conditions leading to the expected mMIF protein in high purity, which was confirmed by different analytical methods. Our results shows the reproducibility of our SPPS approaches to proteins and point out the importance of high-resolution mass spectrometry for a rapid and accurate analysis of such biopolymers.

Pre-evaluation and system optimization of the Elecsys thyroid electrochemiluminescence immunoassays.

We present the results of a pre-evaluation of the thyroid function test free thyroxine, free triiodothyronine and third generation TSH using the Elecsys electrochemiluminescence immunoassay system. A collaborative field study between the development center of the manufacturer and a clinical chemistry laboratory addressed the reliability and comparability of the new Elecsys assays to established methods under clinical laboratory conditions using samples from routine in vitro thyroid testing. Preliminary (reference) formulations of the reagents and several electrochemiluminescent pilot models were used for assay measurements, either in the company's research center or in the clinical setting. The new thyroid assays were compared with the respective Enzymun-Test assays, performed on the ES300 automated immunoassay analyzer. A WHO standard was used for standardization of TSH, whereas an equilibrium dialysis method was applied for free triiodothyronine. The free thyroxine assay was standardized against the Enzymun-Test free thyroxine assay, which had previously been calibrated against equilibrium dialysis. The aim of this field study was to support the optimization of the technology used for Elecsys in an early stage of development and thereby prepare the ground for the adaptation of the immunoassays to the final Elecsys 2010 random access analyzer. A subsequent multicenter evaluation demonstrated that the requirements of routine thyroid testing in terms of reliability were fulfilled by the system.

Allergic reactions after systemic administration of glucocorticosteroid therapy.

OBJECTIVE: To describe patients who developed allergic reactions (ie, erythema on their face and body, itching, flushing, drop in blood pressure, respiratory distress, and cold sweats) immediately after intravenous injection of prednisolone hemisuccinate (SoluDecortin H, E Merck, Darmstadt, Germany). SETTING: Academic medical center. RESULTS: Three of 4 patients had a positive reaction to an intracutaneous test with prednisolone hemisuccinate (SoluDecortin H) but no reaction to the additive sodium succinate. The results of the prick test were negative for all patients. Although no specific IgE antibodies were detected in the serum of these patients, allergic reaction was noted in 3 cases, since standardized techniques to detect antibodies in the serum for hydrocortisone acetate (ie, prednisolone) are lacking. One female patient had a cross-reaction to prednisolone and dexamethasone (Fortecortin, E Merck, Darmstadt, Germany). A renewed application of prednisolone hemisuccinate was well tolerated by all patients when histamine1 and histamine2 receptors were blocked with the use of cimetidine hydrochloride, 200 mg twice per day (1-0-1 ampules, Tagamet, SmithKline Beecham Pharmaceuticals, Philadelphia, Pa) and dimethindene maleate, 4 mg twice per day (1-0-1 ampules, Fenistil, Novartis, Munich, Germany); calcium was given for membrane stabilization. CONCLUSIONS: Allergic reactions to glucocorticoid therapy are only occasionally mentioned in the literature. These reactions appear more often when glucocorticoids are applied topically and may lead to dangerous complications in patients if administered systemically. Therefore, when allergic reactions result from glucocorticoid therapy, (immediate-type reactions should be suspect), consider corticosteroid allergy as a differential diagnosis.