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W Tenschert

Publications and source records attributed to W Tenschert.

67 records · Page 4Linked to original sources

[Diagnosis and therapy of hormonally active cancer of the adrenal cortex. Study of 5 cases].

Adrenocortical carcinomas are very rare tumors. The diagnosis and therapeutic results in 5 female patients are reported. In 4 cases the tumor displayed biochemical and clinical features of Cushing's syndrome, while one was an adrenocortical carcinoma with hypersecretion of aldosterone only. The mean age was 53.6 +/- 8.2 years. In all four cases with Cushing's syndrome the diagnosis was established by measurement of urinary free cortisol extraction rates and excretion rates of 17-ketogenic steroids (mean 1794.5 +/- 1968 micrograms/24 h for free cortisol and 50.5 +/- 24.9 mg/24 h for 17-ketogenic steroids), while the excretion of 17-OH-steroids was in the normal range in one case with hypercortisolism. The patient with mineralocorticoid excess showed markedly elevated plasma aldosterone levels (840 pg/ml) and undetectable plasma renin activity (less than 0.2 ng/ml/3 h), but normal urinary excretion rates of 17-hydroxy- and 17-ketosteroids. The adrenal lesions were localized by intravenous pyelography or sonography and by angiographic procedures, while radioscanning by 131I-cholesterol showed no uptake of activity. Unilateral adrenalectomy was performed in four cases. After appearance of hormonally active metastases o,p'DDD was administered as an antitumor agent in 3 patients. Two of these patients died 10 and 25 months after surgery. One patient with multiple lung metastases is still alive, with a postoperative course of more than 80 months.

Adrenal Cortex Hormones↗

Receptor dysfunctions in human disease.

The characterization of binding parameters of hormones and drugs to specific receptors at various human cell types have introduced an interesting approach for the evaluation of pathogenic mechanisms involved in endocrine and metabolic disorders. The dysregulation of cellular receptors in those disease include changes in receptor number, changes in binding affinity and production of antibodies against receptor molecules. It can be concluded from these observations that altered receptor physiology may be of important value for abnormalities in cellular recognition and control mechanisms which can be observed in neoplastic, inflammatory, immune and developmental diseases.

Adenylyl Cyclases↗

[Receptor dysfunction as a pathogenetic principle in hormone resistance and metabolic diseases].

The characterisation of receptor sites of hormones to various tissues in vivo and in vitro have introduced new insights for the evaluation of pathogenic mechanisms involved in endocrine and metabolic human diseases. Disorders at the receptor level are characterized by changes in the number of receptor sites, the affinity of the hormone to its specific receptors or by generation of anti-receptor antibodies, which impair hormone binding procedures or post-receptor metabolism. Altered receptor physiology may be of an important value as well for diagnosis and treatment of endocrine, metabolic and neoplastic diseases as for the understanding of their pathogenetic mechanisms.

Acanthosis Nigricans↗

[Special diagnosis in Cushing's syndrome].

The diagnostic results in 32 patients (23 female, 9 male) with Cushing's syndrome are presented. 20 patients had pituitary Cushing's syndrome (mean age 36.2 +/- 15.9 years), 7 unilateral adrenal adenoma (mean age 37.1 +/- 15.3 years) and 4 (mean age 54.8 +/- 10.8 years) carcinoma of one adrenal gland. One patient had an ectopic ACTH syndrome based on a Zollinger-Ellison syndrome. Hypertension was observed in 84% of the 32 patients. The basal urinary excretion rates were pathologically high in 99% of all measurements, while the excretion rates for 17-OH-steroids were pathologically elevated only in 61% of all measurements. Radioscanning of the adrenal glands was performed in 11 patients with 131I-cholesterol derivatives of NP-59. 4 patients with pituitary Cushing's syndrome had bilaterally increased uptake of activity, while 3 patients with adenoma had uptake of the radiolabeled drug on the side of the lesion. In all 4 patients with a carcinoma, uptake was absent or insufficient. The results show that measurement of the basal urinary excretion rate of free cortisol is a more sensitive means for detection of hypercorticism than measurement of 17-hydroxysteroids. Radioscanning of the adrenal glands provides reliable results in pituitary Cushing's syndrome and adenomas, but, in our cases, not in carcinomas.

17-Hydroxysteroid Dehydrogenases↗

125I-8-L-arginine vasopressin binding to human mononuclear phagocytes.

The binding of vasopressin to human circulating blood cells was examined. Direct binding studies with preparations of single cell types indicated that the mononuclear phagocyte system is almost entirely responsible for binding of the hormone. Binding of 125I-8-L-arginine vasopressin (AVP) (40 pM) in the presence of excess unlabeled hormone was saturable (2.8 +/- 0.4 fmol/2 x 10(6) cells per ml), was linear with cell number, was dependent upon the concentration of the radioligand used, and was reversible. Binding equilibrium was achieved in 30--40 min at 22 degrees C. Scatchard analysis of binding at this time showed an apparent dissociation constant of 25 +/- 0.21 pM, providing an estimate of 640 +/- 80 sites/cell. Pretreatment of the cells with cytochalasin B, an agent that can block phagocytosis, did not modify radioligand binding, which indicates that 125I-AVP uptake by the cells is due to binding and not to endocytosis. Specificity of vasopressin-sensitive sites on mononuclear phagocytes was demonstrated with a series of vasopressin analogues with various degrees of antidiuretic potency, and with peptide hormones that bind to specific receptors on circulating blood cells but that lack antidiuretic activity. AVP (40 pM) elevated the intracellular level of cyclic AMP from 137 +/- 8.6 to 350 +/- 20.5 pmol/mg cell protein. The binding affinities of the various analogues were correlated with their ability to stimulate intracellular cyclic AMP synthesis (Lys8-vasopressin less than deamino(8-D-Arg)-vasopressin less than oxytocin).

Arginine Vasopressin↗

Lateralization procedures in primary aldosteronism.

The diagnostic validity of adrenal isotopic scanning, adrenal venous aldosterone, adrenal phlebography and computed abdominal tomography (CT) was studied in 44 patients with primary aldosteronism. In all patients the diagnosis was confirmed by surgery (unilateral adrenal adenoma n = 32, bilateral adrenal hyperplasia n = 12). Both adrenal scintiscan, adrenal venous aldosterone and CT allowed in a comparable high percentage of patients (71%0 the exact classification of the adrenal lesion(s), whereas adrenal phlebography could distinguish adenoma from hyperplasia in 57%. Marked differences between the lateralization procedures, however, were observed in predicting incorrect preoperative indentification: adrenal scintiscan 29%, adrenal venous aldosterone 3%, adrenal veno-graphy 6% and CT 0%. Finally, the percentage of patients in whom no differentiation between the two main subgroups of primary aldosteronism could be obtain varied between 0% with adrenal isotopic scanning and 37% with adrenal phlebography (CT 29% and adrenal venous aldosterone 26%). Both scintiscan and adrenal venous aldosterone were not improved by the administration of dexamethasone. Our findings document that adrenal venous aldosterone determinations, adrenal isotopic scanning and computed tomography are equally valid in differentiating unilateral adenoma from bilateral adrenal hyperplasia in primary aldosteronism. However, adrenal scintiscan is hampered by a relative high percentage of incorrect results independant whether dexamethasone was used or not. Contrary, adrenal venous aldosterone and computed tomography seemed to have no or only a minor risk in assuming an incorrect classification of the adrenal lesion(s).

Adenoma↗

[Hypertension in unilateral (non-vascular) nephrosclerosis: renin activity in the venous kidney blood and effect of nephrectomy].

13 patients (9 females, 4 males) with hypertension and unilateral (non-vascular) small kidney underwent nephrectomy. Before surgery, renin activity (PRA) was measured in renal vein blood before and/or 15 and 30 minutes after intravenous stimulation with 40 mg furosemide. From these PRA values renin rations (PRA affected side/PRA unaffected side) were calculated. A ratio of greater than or equal to 1.5 was considered to be significant. After a mean postoperative observation period of 3.9 +/- 1.3 years 6 patients (46%) were cured and 6 were improved. In only 1 patient (8%) did hypertension remain unchanged. No differences could be observed between the renin ratios of cured and improved cases. Furthermore, in no patient was a correlation found between preoperative renin ratios and the degree of postoperative blood pressure reduction. Finally, both patients with renin ratios less than or equal to 1.4 were cured by surgery. Marked differences between cured and improved patients were seen in preoperative blood pressure values, age, duration of hypertension and renal function. Cured patients were younger and had much lower mean systolic and diastolic blood pressure values, shorter duration of hypertension and better renal function than improved patients. These results show that the diagnostic and prognostic validity of renal venous renin ratios is very limited in patients with a unilateral (non-vascular) small kidney. In these patients the effect of nephrectomy can already be predicted by analyzing simple anamnestic, clinical and chemical data.

Adolescent↗

[Minoxidil in treatment resistant hypertension].

22 patients (4 female, 18 male, mean age 47 +/- 10.7 years) with severe essential hypertension (n = 21) and renovascular hypertension (n = 1) were treated with a mean daily dosage of 16.3 +/- 5.1 mg minoxidil for up to 42 weeks. In addition, all patients received a diuretic (hydrochlorothiazide or furosemide) and a beta-blocker (pindolol or propranolol). 8 patients were treated simultaneously with alpha-methyl-dopa. Within one week minoxidil led to a significant reduction in both systolic and diastolic supine blood pressure (p less than or equal to 0.005) from 201.3 +/- 29.0/125.4 +/- 19.2 mm Hg to 172.8 +/- 28.3/106.0 +/- 19.9 mm Hg. The maximum initial blood pressure response was observed after 3 weeks with a mean daily dosage of 12.2 +/- 9.4 mg of minoxidil (160.5 +/- 20.7/99.4 +/- 13.8 MM Hg, p less than or equal to 0.001). Throughout the remaining period a constant and significant reduction in supine systolic and diastolic and upright diastolic blood pressure was achieved (p less than 0.005-less than 0.001) whereas at times systolic blood pressure values could not be lowered significantly. Body weight and pulse rate showed no significant changes throughout the study. In some cases furosemide had to be added by up to 500 mg/day to counteract minoxidil induced water and salt retention. Only moderate doses of beta-blockers were required to prevent a drug induced rise in pulse rate. In these patients a significant change in renal function was not observed. The results show that minoxidil is a potent drug in the treatment of severe essential hypertension.

Adult↗

[Renovascular hypertension. Prognostic value of renal venous renin determinations (author's transl)].

In the present study the effect of surgery on blood pressure was investigated in 35 patients with renovascular hypertension: 17 patients with fibromuscular hyperplasia (FMD) and 18 with atherosclerosis (ASS) of the renal artery. Patients with FMD were younger (31,8 years), showed a shorter duration of hypertension (1.8 years) and were prevalently female (82%), whereas patients with ASS were markedly older (48.2 years), showed a longer duration of hypertension (2.6 years) and were most often male (78%). In both groups of patients the intravenous urogram was positive in a comparable high percentage (FMD=64%, ASS=61%). Following surgical intervention 47%(n=8) of the 17 patients with FMD were cured, 47% (n=8) were improved and only 6% (n=1) showed insufficient reduction of blood pressure values. In ASS the respective values were 28, 55 and 17%. Consequently a good effect of surgery (cured and improved) was observed in 88.5% of all patients. Patients with ASS who failed to respond to surgery (n=3) showed a remarkable long duration of hypertension (7.0 plus or minus 1.4 years). Plasma renin activity (PRA) was determined preoperatively in both renal veins in all 35 patients. From these values the PRA-ratio (PRA affected/unaffected side) was calculated. In 27 patients PRA determinations were repeated following (15 and 30 min) intravenous injection of 40 mg furosemide. PRA-ratios of larger than or equal to 1.5 were considered to be significant. In 31 patients with unilateral renovascular hypertension PRA-ratios were correlated to the postoperative blood pressure reduction. No significant differences in mean PRA-ratios were observed between cured and improved patients. Furthermore, for the total group of 31 patients no significant correlations were obtained between PRA-ratios and postoperative blood pressure reduction. Our results do not support the widespread opinion that PRA determinations in both renal veins are useful to predict the effect of surgery in patients with unilateral renovascular disease. Therefore, from our experience this method should not be recommended as obligatory in the diagnostic work-up of renovascular hypertension.

Adult↗

Nosocomial infections by Listeria monocytogenes: analysis of a cluster of septicemias in immunocompromised patients.

From December 1994 to November 1995 an unusual accumulation of Listeria infections occurred at the University Hospital Hamburg-Eppendorf, Germany. Eleven immunosuppressed patients from different departments developed septicemia due to Listeria monocytogenes during hospitalization. In a retrospective study, serotyping and pulsed-field gel electrophoresis revealed that six isolates were identical or genetically related. Four of them had been isolated from renal transplant recipients. Listeria monocytogenes was neither detected in food samples of the renal transplantation ward, nor in stool specimens obtained from the ward staff. There had been no close contacts among the infected patients. Before transplantation, the renal transplant recipients had been dialysed in different dialysis centers. Nosocomial foodborne transmission could not be proven but seems likely.

Adult↗