No abstract

Distinguishing Graves' disease (GD) from a toxic multinodular goiter (TMG) subgroup with a diffuse but uneven Tc-distribution depends on the diagnostic power of the TSH-receptor antibody (TRAb) determination. Bioassays using CHO cell lines expressing the hTSH-receptor or a new TBII assay, which uses the hTSH-receptor as an antigen (DYNOTEST TRAK human, Brahms, Germany), showed a higher sensitivity for the detection of TRAbs in patients with GD than assays using solubilized porcine epithelial cell membranes. The aim of this study was to investigate whether the new Dynotest TRAK human assay has an increased sensitivity to distinguish GD from non-autoimmune hyperthyroidism. Therefore, we examined 21 consecutive patients with the initial diagnosis of TMG for thyroid-stimulating antibodies (TSAbs, JP26 cell assay) and TBII with the new highly sensitive Dynotest TRAK human (Brahms, Germany). The initial diagnosis of TMG was based on suppressed TSH and a patchy Tc-uptake of more than 1 % and less than 7 % or TSH of more than 0.3 mIE/l with a patchy Tc-uptake of more than 1.5 % and less than 7 % and negative TBII values in a displacement assay using solubilized porcine epithelial cell membranes (TRAK, Brahms, Germany). 11 sera from these 21 patients showed TSAb activity. Furthermore, 10 of these 11 TSAb-positive sera were also positive in the Dynotest TRAK human assay, whereas one serum sample was borderline positive. TSAb activity and inhibition of (125)I-bTSH binding in the Dynotest TRAK human assay correlated well (r = 0.7). Therefore, 11 of the 21 investigated patients initially classified as TMG actually had GD, which was undetectable using the porcine TBII assay. In conclusion, TSAbs or TRAbs detected with the Dynotest TRAK human have the highest diagnostic power to differentiate GD from TMG. Because of the less cumbersome assay technique, the Dynotest TRAK human measurements should be obtained for all patients with non-typical TMG to differentiate GD from non-autoimmune hyperthyroidism in order to select the appropriate therapy for these patients.

No abstract

No abstract

Previous studies have indicated pre-existing subclinical Graves' disease (GD) in many patients with the scintigraphic diagnosis of disseminated thyroid autonomy (DISA) or toxic multinodular goitre (TMG) type A. After radioiodine (RAI) treatment, an increase or the induction of TSH-receptor antibodies (TRAbs) in patients with GD or TMG has been repeatedly reported. In the present study, we investigated whether RAI could induce TRAbs in patients with TMG in whom pre-existing GD was excluded with highly sensitive TBII and TSAB assays. Therefore, TRAbs, anti-thyroperoxidase antibodies (anti-TPO-Abs) and anti-thyroglobulin antibodies (anti-TG-Abs) were determined in 43 consecutive patients at the nuclear medicine outpatient clinic with the scintigraphic diagnosis of toxic adenoma (TA; n = 20) or TMG type A (n = 11) or type B (n = 12) before and after RAI treatment. After RAI therapy, we detected TRAbs in 36 % (4 of 11) of patients with TMG type A only, whereas TRAbs were not detectable in patients with TMG type B or in patients with TA. Furthermore, 3 of the 4 patients with detectable TRAbs after RAI showed positive anti-TPO-Abs before RAI therapy. These findings provide further evidence for pre-existing GD in patients with TMG type A or DISA as previously suggested. Therefore, patients with TMG type A and high anti-TPO-Abs seem to be at increased risk of developing TRAbs or side-effects such as relapse of hyperthyroidism or thyroid associated ophthalmopathy. These patients therefore require more frequent evaluation after RAI treatment.

No abstract

No abstract

The present study evaluates the isotope renograms, obtained in prone and upright position of 87 patients with 93 mobile kidneys. Scintiphotos were made to determine the extent of renal movement. The transient position abnormality of the kidney was compared to the position dependent isotope renogram changes. It was possible to describe three types of floating kidney each with a characteristic motion and position dependent function disturbance. One form of renal ptosis, ptosis with ventral rotation, was commonly associated with a 2nd phase renogram abnormality and with hypertension.