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A desmopressin-induced ACTH increase has been recently suggested to be specific for pituitary-dependent Cushing's disease. We present the case of a 47-year-old woman with Cushing's syndrome due to ectopic ACTH production by a bronchial carcinoid. While CRH failed to induce an ACTH or cortisol response, intravenous administration of desmopressin led to a 47% increase in serum ACTH and a 42% increase in serum cortisol concentration. After surgical removal of the tumour, the desmopressin response became negative. In vitro, ACTH production by tumour cells obtained at surgery was also stimulated by desmopressin but not by CRH. Additional receptor mRNA expression studies using RT-PCR revealed expression of both V2 and V3 vasopressin receptor subtypes in the carcinoid tumour at a level comparable to that recently described in pituitary corticotroph adenomas. This case illustrates that ACTH stimulation by desmopressin is not specific for pituitary-dependent Cushing's syndrome as vasopressin receptor subtypes known to interact with desmopressin may also be found in ectopic tumours producing ACTH.

Goitre is the cardinal symptom of most thyroid diseases and treatment is often influenced by the evaluation of thyroid size. Quantitative palpation of the thyroid gland could offer a quick and easy initial examination method for discovering most thyroid diseases. However, this clinical technique is frequently underestimated and its accuracy is not evaluated. Therefore, we examined the question whether thyroid volume can be determined with sufficient precision by manual palpation. 316 patients with suspected thyroid diseases were selected at random at our hospital and prospectively studied. Thyroid volume of each patient was assessed by palpation followed by ultrasonically scanning. The examinations were performed by two physicians: an endocrinologist (A) and a resident (B) who had undergone a structured palpation training. Ultrasonic scanning of 99 thyroid glands revealed a high level of agreement (r2 = 0.87) between both physicians. Examiner A evaluated 111 patients by palpation and ultrasonic scanning. The mean volume determined by ultrasound was 35.9 ml (SD = 27.1 ml) with a range of 4-152 ml. This correlated well with the results of palpation (r2 = 0.872). Examiner B evaluated 215 patients. These ultrasonically determined volumes had a mean value of 37.3 ml (SD = 24.2 ml; range 4-145 ml) and correlated well with the results obtained by palpation (r2 = 0.856). A total of 53 patients were examined by both physicians. The interobservers' comparison of the palpation results yielded an excellent correspondence (r2 = 0.893). We conclude that the manual palpation technique yields sufficiently precise quantitative results for clinical purposes and can be taught. Clinical assessment of thyroid size on a routine basis should result in better diagnostic strategies for thyroid diseases and in cost savings.

History and Clinical Findings: A 54-year-old man was hospitalised because hypercalcaemia and associated renal failure were suspected. He had a history suggesting gastric ulcer, with nonspecific back and shoulder pain and spontaneously passed kidney stone. On admission the patient reported reduction in physical fitness, fatigue, headache and nausea without vomiting. Physical examination was unremarkable except for pain on pressure over the thoracic and lumbar vertebrae., Investigations: Hypercalcaemia of 3.9 mmol/l was found while parathormone was low. Serum creatinine concentration was 2.8 mg/dl. Malignancy was excluded after extensive tests. A florid gastric ulcer was demonstrated, together with Helicobacter pylori infection. Computed tomography revealed stippled calcifications in the kidneys., Treatment and Course: Renal function markedly improved, the hypercalcaemia disappeared and the parathormone level rose within four days of the administration of sodium chloride (2.51 daily of a 0.9% solution) and of furosemide (40 mg daily). Repeat questioning of the patient revealed that because of stomach pains he had for four years been taking up to 6 g calcium carbonate daily in the form of a prescription-free antacid. He was thereupon treated for a milk-alkali syndrome. Calcium concentration became normal, while renal function has remained slightly impaired a year later. The ulcer has healed without recurrence on eradication of the Helicobacter pylori infection with amoxicillin and omeprazole., Conclusions: The danger of some "over the counter" prescription-free medications should not be underestimated and patients should be routinely questioned about them. Absorbable antacids should no longer be taken in the treatment of peptic complaints now that effective antacids, H2-receptor antagonists and proton-pump inhibitors have become available.

Thyroid sonography was used to assess 2322 patients attending our clinic over a 3-year period. Sonography, in combination with clinical and laboratory findings, enabled us to detect autoimmune thyroiditis in 123 patients, 67 of whom could be classified as euthyroid, 17 as latent hypothyroid, and 39 as overtly hypothyroid. Consequently without the use of sonography (or thyroid antibody measurements) it would not have been possible to make a diagnosis in over half of our patients with autoimmune thyroiditis. Sonography was also of considerable value in establishing the absence of autoimmune thyroiditis as out of the 2322 patients we examined, autoimmune thyroiditis could be excluded on the basis of sonography alone (absence of diffuse hypoechoicity) in 1962 (84%). Thyroid volume ranged from less than 5 to 112 ml with the majority of patients having a volume of 21-30 ml and the overtly hypothyroid group showing a shift to smaller volumes. The data suggested that thyroid volume changes over the range of the disease from euthyroid to overtly hypothyroid.

PTH antibodies were raised in two sheep (S 469 and S 478) by immunizing with porcine and bovine parathyroid extracts. Both antisera were characterized with various PTH preparations and fragments. Both antisera cross react with human, bovine and porcine PTH, one antiserum also binds rat PTH. Region specificity could be attributed to the mid region of the PTH molecule with particularly high affinities of both antisera for the fragment 44-68 hPTH. S 478 has similarly high affinity for intact hormone (affinity constants 0.6 x 10(13) l/mol), while S 469 has much higher affinity for the 44-68 fragment (affinity constant 0.84 x 10(13) l/mol) than for intact hormone. The antibodies are useful not only for clinical radioimmunoassay, but also for experimental work. They have been distributed to many laboratories.

The basis for the radioimmunoassay of parathormone (PTH) as a routine method is a new sheep antiserum and a labelled PTH stabilised by a modification of the purification technique. The antiserum is obtained by immunisation with pig and cattle parathormone, it is C-terminal specific and is used in the assay in a final dilution of 1:35000. The affinity to human PTH is markedly greater than of the antisera used up to now. Two purification steps of 125J labelled bovine PTH lead to a tracer with a nonspecific binding of approximately 5% which increases to approximately 10% within 6 weeks. All normal sera investigated so far were measurable quantitatively (normal range 0.7 to 2.5 mul/equiv.). The lower sensitivity range was at 0.3 mul/equiv. All patients with chronic renal insufficiency and dialysis patients have an increased PTH concentration (3.9 to greater than 20 mul/equiv.). This also applies to patients with primary hyperparathyroidism (2.9 to greater than 20 mul/equiv.).

A 2-compartmental analysis of 47Ca kinetics was carried out in 21 patients with primary hyperparathyroidism (pHPT) and 7 healthy control subjects. The results were compared with serum concentrations of calcium, inorganic phosphorus, alkaline phosphatase, and immunoreactive parathyroid hormone (iPTH). The well known increase in exchangeable calcium was found to be not uniform in its subcompartments and with a marked predominance of the osseous fraction. The most important result was the increase of calcium efflux from osseous into extraosseous exchangeable calcium in agreement with the results of Talmage et al. studying PTH actions on calcium flux rates between blood and bone in rats. The increased calcium efflux in pHPT was the only kinetic parameter correlated with serum iPTH. Neither increased calcium accretion indicating high bone turnover, nor serum calcium concentrations and exchangeable calcium fractions correlated with serum iPTH. These results lead to the following conclusions: radiocalcium kinetics provides valuable parameters of bone calcium turnover (osseous exchangeable calcium, bone-calcium efflux, and calcium accretion). Calcium efflux from exchangeable bone calcium, determined kinetically, might be related to PTH induced calcium transport from bone fluid compartment to extracellular fluids according to the concept of Talmage 1977.

Out of 2,322 patients attending a thyroid clinic in north west Germany over a three year period, 123 were found to have evidence of autoimmune thyroiditis (hypothyroid, latent hypothyroid or euthyroid) and 96 were available for further analysis. TSH receptor antibodies (TRAb) were detectable by receptor assay in five of these patients (and a further two who attended the clinic later) and all the TRAb positive sera showed TSH blocking activity by bioassay. All of the patients with blocking activity were hypothyroid (on treatment) and represented 15% of this group of 34 patients. This suggests that in hypothyroid patients with autoimmune thyroiditis, the prevalence of TSH receptor antibodies with blocking activity is similar in northern Europe and Japan (21% of 43 patients; (1]. In the present study, no relationship between thyroid volume as assessed by sonography and the presence or absence of blocking antibodies was apparent. As blocking antibodies were undetectable in patients at early stages of the disease (i.e., in the euthyroid or latent hypothyroid groups) it seemed unlikely that these antibodies were a major causative factor in the development of hypothyroidism.