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Christoph Reiners

Publications and source records attributed to Christoph Reiners.

35 records · Page 2Linked to original sources
PubMed2004

Prevalence of thyroid disorders in the working population of Germany: ultrasonography screening in 96,278 unselected employees.

Germany continues to be iodine deficient despite considerable improvement in the past years. To assess the current prevalence of diffuse and/or nodular thyroid disorders, a cross-sectional observational study in a nonrandom sample of the working population was carried out throughout Germany in 2001 and 2002. A total of 96,278 employees 18-65 years of age from 214 companies or other private or public institutions voluntarily underwent ultrasonographic examinations by 230 experienced investigators. To compare the prevalence of different abnormal findings in relation to age and gender, descriptive statistics and the Kruskal-Wallis test were used. Data from volunteers with previous thyroid treatment (13.0% of total sample) were not included in the analysis. Abnormal findings (goiter and/or nodules > 0.5 cm) were observed in 33.1% (men, 32.0%; women, 34.2%) of the examined patient population, an enlarged thyroid without nodules in 9.7% (men, 11.9%; women, 7.6%), nodules only without enlargement of the thyroid in 14.3% (men, 11.5%; women, 17.0%), and nodular goiter in 9.1% (men, 8.6%; women, 9.6%). Nodules (with or without goiter) between 0.5 and up to 1.0 cm were found in 10.0%, and nodules above 1.0 cm in 11.9% of the population. Rates of abnormal findings increased with age in both genders. Goiter was more common in men, nodules in women. In light of these findings, the prevalence of thyroid disorders in Germany continues to be high. Although the study may slightly overestimate the prevalence, about one third of the working population is affected and remains unaware of this condition. These results emphasize the importance of effective sonographic screening to detect early thyroid abnomalities in order to initiate preventive and therapeutic measures to prevent the onset or progression of disease and its sequels.

Adult↗
PubMed2004

Follow-up of low-risk patients with differentiated thyroid carcinoma: a European perspective.

OBJECTIVE: Because differentiated (follicular and papillary) thyroid cancer (DTC) may recur years after initial treatment, the follow-up of patients with DTC is long term. However, this population has changed, with more individuals being discovered at an earlier stage of the disease, so that previous follow-up protocols based mostly on data from high-risk patients no longer apply. We sought to develop an improved protocol for the follow-up of low-risk patients with DTC based on the findings of recent studies. METHODS: We analysed recent literature on the follow-up of DTC. RESULTS: Recent large studies have produced three important findings: (i) in patients with low-risk DTC with no evidence of disease up to the 6- to 12-month follow-up, diagnostic whole-body scan adds no information when serum thyroglobulin (Tg) is undetectable and interference from anti-Tg antibodies is absent; (ii) use of recombinant human thyroid-stimulating hormone to aid Tg measurement is effective and provides greater safety, quality-of-life and work productivity than does levothyroxine withdrawal with its attendant hypothyroidism; and (iii) ultrasonography performed by an experienced operator is the most sensitive means of detecting neck recurrences of DTC. CONCLUSIONS: We present a revised follow-up protocol for low-risk patients taking into account the above findings. This protocol should help clinicians enter a new era of monitoring characterized by greater safety, simplicity, convenience and cost savings.

Adenocarcinoma, Follicular↗
PubMed2004

Three-dimensional ultrasonography for volume measurement of thyroid nodules in children.

OBJECTIVE: The aim of this study was to compare the accuracy of thyroid nodule volume measurements performed by 2- and 3-dimensional ultrasonography and to evaluate the dependence of volume measurement results on nodule size and echographic characteristics. METHODS: Results of multiple 2- and 3-dimensional ultrasonographic volume measurements of thyroid nodules in 102 children with different variants of thyroid nodular disease were reviewed retrospectively. The standardized difference, within-observer variability, and repeatability were estimated for both 2- and 3-dimensional ultrasonography. The mean age of the patients +/- SD in the examined group was 14.9 +/- 2.8 years; the mean volume of thyroid nodules was 0.78 +/- 0.13 mL. RESULTS: The SD of the normalized difference for 3-dimensional ultrasonography (2.8%) showed the clear superiority of its accuracy over 2-dimensional ultrasonography (15.9%; F test, P < .01). Intraobserver variability and repeatability for both examined methods had significant dependence on the nodule outline. For 2-dimensional ultrasonography, the intraobserver variability increased from 14.0% in nodules with a regular outline to 24.5% in those with an irregular outline (P < .001), and for 3-dimensional ultrasonography, it increased from 5.1% to 9.3% (P < .001). Intraobserver repeatability dropped from 85.4% in regular nodules to 74.6% in irregular nodules (P < .001) for 2-dimensional ultrasonography and from 94.7% to 90.4% (P < .001) for 3-dimensional ultrasonography. CONCLUSIONS: Volume measurements by 3-dimensional ultrasonography are more accurate, showing lower intraobserver variability and higher repeatability, than those made by 2-dimensional ultrasonography with less dependence on nodule size and echographic characteristics.

Adolescent↗
PubMed2004

Impact of 131I diagnostic activities on the biokinetics of thyroid remnants.

UNLABELLED: Recent publications described many discrepant findings about thyroid "stunning" after the administration of (131)I diagnostic activities to patients with differentiated thyroid carcinoma. Stunning may play a major role in reducing the therapeutic efficacy of high (131)I activities given for ablation therapy. METHODS: Participation in a multicenter study to investigate differences in iodine biokinetics in the hypothyroid state and after the application of recombinant human thyroid-stimulating hormone enabled us to study quantitative changes in thyroid iodine biokinetics after the administration of 74 MBq of (131)I twice within 6 wk and an ablation activity of 3-4 GBq 7-12 d after the second diagnostic administration of (131)I in 6 patients. RESULTS: The uptake and half-life of the first 74 MBq of (131)I were significantly reduced to a mean of 44% and a mean of 51%, respectively, after the second diagnostic administration and further reduced to a mean of 40% and a mean of 30%, respectively, during ablation therapy. The residence times were reduced to 25% in the second dosimetric assessment and to 10% during therapy compared with the value in the first assessment. For one patient, an estimated absorbed dose as high as 38 Gy was found in the first diagnostic study. The mean dose for all patients after the first assessment was 15 Gy; after each further assessment, the dose was reduced according to the decrease in residence time. CONCLUSION: This study shows a severe impact of 74 MBq of (131)I on the biokinetics of thyroid remnants during subsequent radioiodine therapy.

Adult↗
PubMed2004

[Radioiodine therapy for Graves' disease: problems and new developments].

In Germany, patients with Graves' disease are usually treated with radioiodine after unsuccessful antithyroid drug medication, occurrence of side effects from antithyroid drugs or an increased risk from surgery. In patients with normal or only slightly enlarged thyroid glands (volume < or = 50 ml), radioiodine therapy is particularly effective. Radioiodine is the preferential treatment for Graves' patients with high titres of TSH-receptor antibodies and cigarette smoking. Children are still rarely treated with radioiodine in Germany. In contrast, treatment with radioiodine should be more liberally applied in elderly patients with subclinical hyperthyroidism and cardiac symptoms. Individual dosimetry to determine the therapeutic activity is mandatory in Germany. Patients with large goitres obviously need higher organ doses than patients with smaller goitres or normal thyroid glands. Antithyroid drug treatment may interfere with radioiodine therapy. Therefore, it is recommendable to withdraw antithyroid drugs several days before treatment with radioiodine is initiated (and a preceding radioiodine uptake test is performed). In patients with Graves' orbitopathy prophylaxis with corticosteroids can prevent the worsening of symptoms that may be induced by radioiodine treatment. Currently, a risk adapted procedure is recommended according to which prophylactic medication with corticosteroids before applying radioiodine treatment is not necessary in patients with symptoms of orbitopathy and lack of other risk factors (cigarette smoking, in particular). Present results suggest that the risks of radioiodine treatment in Graves' disease patients are very low, while at the same time the cost-effectiveness of this treatment regimen is high.

Costs and Cost Analysis↗
PubMed2004

Real time RT-PCR analysis of thyroglobulin mRNA in peripheral blood in patients with congenital athyreosis and with differentiated thyroid carcinoma after stimulation with recombinant human thyrotropin.

OBJECTIVE: Thyroglobulin (Tg), measured by immunometric assay, is the most sensitive and widely used clinical marker for thyroid cancer progression and relapse. However, these Tg determinations are of limited sensitivity and susceptible to interference by Tg autoantibodies. As a possible diagnostic alternative, we tested a real time RT-PCR protocol to determine Tg mRNA levels in peripheral blood. METHODS: Tg mRNA was determined by real-time RT-PCR using total RNA from peripheral blood. Tg mRNA blood levels were calibrated to the mRNA encoding the housekeeping enzyme glyceraldehyde phosphate dehydrogenase (GAPDH); pooled blood from ten healthy subjects served as a RT-PCR positive control. RESULTS: Tg mRNA and serum Tg were detected in twelve patients with differentiated thyroid cancer (DTC) after thyroidectomy and radioiodine therapy, however, there was no correlation with the clinical stage. An increase in Tg mRNA and protein was observed after application of recombinant human thyrotropin (rhTSH) in four patients with DTC stimulated with rhTSH for postoperative follow up. Tg mRNA and protein were also detected in four congenital athyreotic patients. Analysis of Tg mRNA levels using a commercial multiple tissue Northern blot revealed Tg hybridization signals in several extrathyroidal tissues (salivary gland, trachea, kidney, pancreas, adrenal gland, etc.). CONCLUSIONS: Our data suggests that RT-PCR detects Tg mRNA of extrathyroidal origin, from leukocytes or from metastasizing carcinoma cells under basal conditions or after TSH stimulation. However, considering the marked and highly variable individual Tg mRNA backgrounds, interpretation of real time PCR results requires caution. This limits the clinical use of Tg mRNA determination by real time PCR to an individual tumor progression marker in follow-up.

Blotting, Northern↗
PubMed2003

Comparison of radioiodine biokinetics following the administration of recombinant human thyroid stimulating hormone and after thyroid hormone withdrawal in thyroid carcinoma.

Iodine kinetics were studied in patients with differentiated thyroid cancer while euthyroid under exogenous thyroid stimulating hormone (TSH) and while hypothyroid to detect differences in radioiodine uptake, distribution and elimination. Nine patients with total or near-total thyroidectomy on thyroid hormone suppressive therapy received two or three daily doses of 0.9 mg recombinant human TSH (rhTSH) followed by administration of a diagnostic activity of 2 mCi (74 MBq) iodine-131. After the biokinetics assessments had been performed, patients stopped taking thyroid hormones to become hypothyroid. A second 2 mCi (74 MBq) diagnostic activity of 131I was administered, followed by a second set of biokinetics assessments. One week later the patients underwent remnant ablation with a therapeutic activity of 131I. A comparison of the 131I kinetics in the patients while euthyroid and while hypothyroid showed major differences in the doses to the remnant as well as in residence times and radiation exposure to the blood. In the first diagnostic assessment the remnant dose was higher in eight of the nine patients and clearance of the activity from the blood was faster in all of them. The data from this study suggest that radioiodine administration is potent and safe when administered to euthyroid patients following rhTSH administration. Enhanced residence time in the remnant and decreased radiation exposure to the blood were noted when patients were euthyroid compared to when they were rendered hypothyroid. However, all patients received diagnostic activities in the same order: first while euthyroid, followed by hypothyroidism. It is quite possible that "stunning" from the radioiodine administered in the initial uptake study inhibited the subsequent uptake of radioiodine by the remnant lesions in the second uptake study.

Adult↗
PubMed2003

High gradient magnetic cell sorting and internal standardisation substantially improve the assay for somatic mutations at the glycophorin A (GPA) locus.

In the MACS-BR6 version of the GPA assay [Int. J. Radiat. Res. 70 (1996) 131] variant red blood cells (RBC) are isolated from 5 x 10(8) normal RBC by magnetic cell separation (MACS) before detection and quantification by immunolabelling and flow cytometry as in the classical BR6 assay. In the present work it is described how the MACS-BR6 assay is improved by internal standardisation with FITC-labelled RBC. This modification of the assay has the advantage that (i) the analysis of variants is not disturbed by the overwhelming number of normal RBC that (ii) the precision of the assay is improved and finally that (iii) a sufficient number of variants is available for further investigations. Tn positive RBC behave in MACS like variants. It is demonstrated that in normal individuals Tn cells (frequency: approximately 2 x 10(-8)) do not disturb the assay.

Adult↗
PubMed2003

Osteoporosis in male hypogonadism: responses to androgen substitution differ among men with primary and secondary hypogonadism.

BACKGROUND: No randomized study exists comparing the effects of different modes of androgen substitution on bone mineral density (BMD). METHODS: We performed a prospective, randomized, trial assigning 53 hypogonadal men to the following treatment groups: mesterolone 100 mg p.o. daily, testosterone undecanoate 160 mg p.o. daily, testosterone enanthate 250 mg i.m. every 21 days, or a single subcutaneous implantation of 1,200 mg crystalline testosterone. The BMD was determined by peripheral quantitative computed tomography. RESULTS: At baseline, men with secondary hypogonadism (n = 33) had a lower BMD (-1.52 +/- 0.23 SDS; Z-scores) than men with primary hypogonadism (n = 20, -0.87 +/- 0.23 SDS, p < 0.01). In men with primary hypogonadism, the BMD increased dose dependently (crystalline testosterone +7.0 +/- 1.3%, testosterone enanthate +4.8 +/- 0.2%, testosterone undecanoate +3.4 +/- 2.5%, mesterolone +0.8 +/- 1.6%) after 6 months of therapy. Only secondary hypogonadal men treated with testosterone enanthate experienced an increase of the BMD. CONCLUSIONS: In primary hypogonadal men the BMD responds dose dependently to testosterone substitution, whereas in secondary hypogonadism only testosterone enanthate treatment significantly increased the BMD.

Adult↗
PubMed2003

Differentiated thyroid cancer in childhood: pathology, diagnosis, therapy.

The incidence of thyroid cancer in childhood amounts to approximately 0,5/100.000/year. However, after exposure to ionizing irradiation, the incidence may increase more than 20 fold. In children, lymph node metastases of differentiated thyroid cancer are frequent (more than 50%); distant metastases mainly to the lung are seen in 20-30%. The method of choice for the primary diagnosis of thyroid cancer today is ultrasonography with 7,5 - 10 MHz probes, accompanied by fine-needle aspiration biopsy. Differentiated thyroid cancer has to be treated with a multidisciplinary approach comprising total thyroidectomy and lymph node dissection, post-operative radioiodine treatment and TSH-suppression by levothyroxine. The long-term results of this treatment approach are generally good with 10-year survival rates of 95% and higher. The treatment of children with disseminated pulmonary metastases however, may be complicated due to the increased risk of the induction of pulmonary fibrosis by radioiodine.

Biopsy, Fine-Needle↗
PubMed2002

Therapy of ankylosing spondylitis with 224Ra-radium chloride: dosimetry and risk considerations.

Ankylosing spondylitis (AS) is a chronic inflammatory rheumatic disease which reduces the quality of life and leads to disability in approximately one-third of the patients. The spectrum of therapeutic modalities is limited. The renaissance of the use of (224)Ra-radium chloride for AS treatment, however, gives rise to concern which should result in the reconsideration of (224)Ra dosimetry and in the discussion of the risks associated with this treatment. The present study introduces new dosimetric calculations for alpha and beta/gamma rays performed according to the model proposed by the International Commission on Radiological Protection (ICRP). After a treatment schedule of 10 intravenous injections, each with 1 MBq of (224)Ra, the absorbed doses were calculated to be highest on the bone surface of the patient (4.4 Gy) with a resulting effective dose of 2.5 Sv.

Adult↗
PubMed2002

Radioiodine therapy of thyroid autonomy.

Over half a century, treatment of thyroid autonomy with an oral dose of iodine-131 has proven to be effective. The optimum management strategy for the patient is, however, still a matter of debate. The article provides an overview of the pathogenesis of functional autonomy and its clinical relevance. According to the guidelines on both sides of the Atlantic, radioiodine treatment is considered the most comfortable and economical approach to the treatment of the toxic nodular goitre. Some differences in the preparation procedures in the guidelines of the American and the German Society of Nuclear Medicine are discussed with respect to therapy results and the subtypes of thyroid autonomy. The results of studies are summarised concerning changes in thyroid function and thyroid volume after a course of radioiodine treatment. Therapy-related risks, such as immunogenic hypothyroidism or thyroid cancer, are discussed. (131)I treatment of functional autonomy and hyperthyroidism is considered an effective and safe procedure.

Adenoma↗
PubMed2002

Impaired salivary gland function reveals autonomic dysfunction in amyotrophic lateral sclerosis.

Recent studies have revealed autonomic dysfunction in amyotrophic lateral sclerosis (ALS). We studied salivary gland function by quantitative scintigraphy in ALS patients (n = 30) and healthy controls (n = 30). Uptake of (99m)Tc-pertechnetate in the parotid and submandibular glands was significantly decreased in ALS patients. No correlation was found between radiotracer uptake and regions of onset (bulbar-limb), duration of disease, or functional scores. Our data show early subclinical autonomic involvement supporting the view that ALS is a multisystem degenerative disease.

Aged↗
PubMed2002

L-arginine deficiency and supplementation in experimental acute renal failure and in human kidney transplantation.

BACKGROUND: The "L-arginine paradox" refers to situations where L-arginine (L-Arg) supplementation stimulates nitric oxide (NO) synthesis, despite saturating intracellular concentrations. This paradox is frequently observed in acute renal failure (ARF). First, the effects of L-Arg on renal function of rats with ARF were studied. Based on the promising results from these initial studies, the second part of our study searched for a form of ARF in humans that could be studied easily under conditions with little variance and yet was linked with endothelial dysfunction. Thus, we investigated the effects of L-Arg supplementation immediately after kidney transplantation in 54 patients. METHODS: In uranyl nitrate-induced ARF in rats the effects of L-Arg and L-NNA (inhibitor of nitric oxide synthase; NOS) on glomerular filtration rate (GFR), renal plasma flow (RPF), blood pressure (BP) and NOx (NO2- +NO3-) excretion were examined. Tissue L-Arg levels, NOS activities, immunodetection of NOS and superoxide dismutase (SOD), activities of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase and xanthine oxidase, and nitrotyrosine immunoreactive protein (NT-IR) were determined and compared to sham operated animals. Secondly, in a randomized, double-blind study, the effects of L-Arg on GFR and RPF were investigated in 54 kidney transplant recipients, receiving IV L-Arg for three days. GFR and RPF were measured on days 1, 3, 5 and 10 by scintigraphy. RESULTS: In experimental ARF, decreased RPF and GFR were associated with reduced tissue L-Arg levels, endothelial NOS-III expression, NO formation and NOx excretion. Reduction in GFR, RPF and NOx excretion were reversed upon administration of exogenous L-Arg. There also was a loss of Cu,Zn-SOD, a key enzyme against oxidative stress, and an elevation of NT-IR, an indicator of nitrosative stress and suggested marker for pathological actions of NO. However, NT-IR was not dependent on de novo NO synthesis and not related to the functional effects of l-Arg administration. In kidney transplant recipients receiving organs with a short cold ischemia time (CIT) and from young donors, that is, those with a higher likelihood of a functional endothelium, early administration of L-Arg improved renal function. CONCLUSION: Both experimental and clinical data show that \L-Arg deficiency and endothelial dysfunction are pathomechanistically relevant in ARF. The data suggest a therapeutic potential for the administration of L-Arg in ARF and kidney transplantation, at least in patients receiving kidneys with shorter CIT and from younger donors.

Acute Kidney Injury↗
PubMed2002

Technical evaluation of a new immunoradiometric and a new immunoluminometric assay for thyroglobulin.

BACKGROUND: After removal of differentiated thyroid carcinoma (DTC), serum thyroglobulin (Tg) can indicate persistent or recurrent disease. We describe two novel two-step assays designed to measure low Tg concentrations. METHODS: We evaluated prototypes of the new IRMA, DYNOtest Tg-pluS, and the new immunoluminometric assay (ILMA), LUMItest) Tg-pluS. In the first step, a high-salt incubation buffer leads to dissociation of Tg-Tg antibody complexes in serum and is intended to reduce nonspecific interference and interference of potential Tg autoantibodies in the system. We studied recovery of human Tg (from thyroid glands) added to horse serum. We also studied 58 patients with DTC in whom Tg values under thyroid-stimulating hormone (TSH) suppression and TSH stimulation (without thyroxine) were available. RESULTS: The detection limits were 0.04 microg/L Tg for the IRMA and 0.02 microg/L for the ILMA. Intraassay imprecision (CV) was <10% over the range of the calibration curve in both assays. The day-to-day CV was <20% at 0.2 microg/L for the IRMA and at 0.06 microg/L for the ILMA. No high-dose hook effect was seen with up to 200 000 microg/L added Tg or in dilutions of 12 patient sera with Tg values of 307-38 880 microg/L. Mean recovery of 50 microg Tg/L was 96% in those patients. Among 77 samples with Tg antibody values of 65.2-8150 kilounits/L, recovery by the IRMA was disturbed in 7 cases (9%) and by the ILMA in 9 cases (12%). Tg increased as measured in both assays in 50 of 58 patients after thyroxine withdrawal. CONCLUSIONS: The new assays have improved precision for Tg <1 microg/L, and even low measured Tg concentrations respond physiologically to thyroxine withdrawal. The assays are free of a high-dose hook effect up to a Tg concentration of at least 38 000 microg/L and may further reduce Tg antibody interference.

Autoantibodies↗