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G Pieters

Publications and source records attributed to G Pieters.

At least 19 recordsLinked to original sources
PubMed1992

Residual adrenocortical function after bilateral adrenalectomy for pituitary-dependent Cushing's syndrome.

The incidence of residual, functioning adrenal tissue in patients treated by total bilateral adrenalectomy for Cushing's disease is not known. Between 1962 and May 1988 50 patients with Cushing's disease were treated by bilateral adrenalectomy. Of these patients, 29 underwent surgery between 1962 and 1980, when bilateral adrenalectomy was the treatment of first choice in our hospital in patients with pituitary-dependent Cushing's syndrome. In 37 patients the presence or absence of cortisol-producing tissue could be evaluated (follow-up period, median and range, 8.3 and 0.1-18.9 yr). Evidence of functioning cortisol-producing tissue (plasma cortisol level > 50 nmol/L after stopping glucocorticoid and mineralocorticoid substitution therapy for 24 h) was found in 9 patients (24%). Plasma cortisol levels in these 9 patients varied between 60 and 330 nmol/L (mean +/- SD, 180 +/- 100 nmol/L). Signs and symptoms of recurrent Cushing's syndrome were present in only 1 patient. There was no difference in plasma ACTH levels and duration of follow-up between the patients with and without evidence of functioning cortisol-producing tissue. In all 9 patients detectable aldosterone levels indicated endogenous mineralocorticoid production, whereas in only 1 patient adrenaline was detectable in the circulation. In 8 of the 9 patients suspected of functioning cortisol-producing tissue we performed a stimulation test with synthetic ACTH (1-24). In 2 patients plasma cortisol levels rose, in 6 they remained virtually unchanged. Although we found clinically relevant signs and symptoms of Cushing's syndrome in only 1 of the 50 patients, the relatively high incidence of residual, functioning adrenal tissue after "total" adrenalectomy for pituitary-dependent Cushing's syndrome necessitates continuous surveillance for recurrent Cushing's syndrome. There is no place for routine administration of full replacement doses of glucocorticoids after total adrenalectomy.

Adolescent↗
PubMed1992

The natural course of multiple endocrine neoplasia type IIb. A study of 18 cases.

BACKGROUND: Multiple endocrine neoplasia (MEN) type IIb is an autosomal dominantly inherited disorder associated with medullary thyroid cancer, pheochromocytoma, and a characteristic phenotype. The present study was performed to investigate the natural course of the syndrome and to describe its expression. METHODS: The medical records of 18 patients with MEN IIb, seven male and 11 female, were reviewed. RESULTS: The mean age at diagnosis of MEN IIb was 18 years (range, 8 to 41 years). All 18 patients had medullary thyroid cancer. In three patients, medullary thyroid cancer was diagnosed via screening. In two of these patients, the calcitonin value normalized after thyroidectomy. One patient died of metastases from medullary thyroid cancer at the age of 20 years (median duration of follow-up, 10 years). Eight of the 18 patients had pheochromocytomas. All of our patients had neuromas and bumpy lips, and all but one had a marfanoid habitus. A large proportion of the patients had intestinal abnormalities (75%), thickened corneal nerves (69%), skeletal abnormalities (87%), and delayed puberty (43%). CONCLUSIONS: The course of medullary thyroid cancer in MEN IIb is not always as aggressive as is generally thought. Periodic examination of relatives who are at risk may lead to early diagnosis and curative treatment. Intestinal abnormalities, skeletal abnormalities, and delayed puberty are commonly found in association with MEN IIb.

Adolescent↗
PubMed1991

Pathophysiology of thermoregulation in patients with poikilothermia.

To investigate the thermoregulatory mechanisms underlying poikilothermia in man, we have studied 4 female patients (age 28-37 yr) with poikilothermia, most probably of hypothalamic origin, as well as 4 female volunteers of similar age. In a climatic chamber the participants were subjected to cold stress (16.5 degrees C) and subsequent heat exposure (40 degrees C). In the volunteers cold stress did not influence the rectal temperature; cooling induced a marked shivering response and an immediate peripheral vasoconstriction. Subsequent heat challenge induced a slight rise in the rectal temperature (from 36.3 +/- 0.2 to 37.0 +/- 0.3 degrees C) and a marked sweat secretion in all control subjects. All patients were hypothermic at the start of the experiment. Cooling induced a decrease in the rectal temperature of 0.3-0.9 degrees C. Three patients showed neither peripheral vasoconstriction nor a shivering response to cold stress. In contradistinction to the control subjects, in all patients an afterdrop of the rectal temperature of 0.3-0.5 degrees C was observed once heating of the environment had started; thereafter a progressive rise in core temperature occurred up to 38.5 (38.0) degrees C. In none of the patients sweat secretion was clinically visible. These results reveal that in these patients with poikilothermia the disorder of thermoregulation is accompanied by inadequate cutaneous vasomotor adjustment and disturbed sweat response and likely reduced metabolic response to cold stress.

Adult↗
PubMed1990

Concurrent hypercortisolism and hyperaldosteronism due to an adrenal adenoma.

The case of a 39-year-old woman with Cushing's syndrome, hypertension and severe hypokalemia, caused by a unilateral adrenal adenoma composed of cells of the zona fasciculata histological type, is described. Plasma renin activity, plasma levels of mineralocorticoids and the aldosterone secretion rate were determined before and after surgical removal of the adenoma. The tumor appeared to produce autonomously cortisol as well as corticosterone, 18-hydroxycorticosterone and aldosterone. This condition has not previously been described in the literature and might be explained by strong expression of the full spectrum of activities of the mitochondrial enzyme P450 C11 by the tumor cells. Interestingly, despite hyperaldosteronism, plasma renin activity was not suppressed.

Adenoma↗
PubMed1989

Do weak mineralocorticoids affect the pathogenesis of hypertension in Cushing's disease?

Few studies have examined the effect of the weak mineralocorticoids corticosterone, 18-hydroxycorticosterone and 18-hydroxydeoxycorticosterone on the pathogenesis of hypertension in Cushing's disease. Therefore we measured plasma levels of these mineralocorticoids together with plasma aldosterone, plasma renin activity and the aldosterone secretion rate in 12 patients with Cushing's disease and in seven patients with essential hypertension. Plasma levels of aldosterone, corticosterone, 18-hydroxycorticosterone and 18-hydroxydeoxycorticosterone and the aldosterone secretion rate were similar in both groups of patients. Plasma renin activity, determined after 4 h of ambulation, was significantly higher in Cushing's disease than in essential hypertension. We conclude that it is unlikely that either aldosterone or the weak mineralocorticoids corticosterone, 18-hydroxycorticosterone and 18-hydroxydeoxycorticosterone play a specific role in the pathogenesis of hypertension in Cushing's disease.

Adult↗
PubMed1989

Lateral decompression of a pathological disc in the treatment of lumbar pain and sciatica.

The posterolateral approach external to the vertebral canal allows decompression and the escape of disintegrating bits of abnormal nucleus pulposus. This simple, rapid, and least traumatic procedure is sufficient to relieve and to cure a significant number of patients (approximately 40%) suffering from intervertebral disc-related lumbar pain or sciatica. Among 225 patients with 338 discs operated on by the lateral decompression technique in the interval from 1978 to 1984, the overall results are encouraging.

Adult↗
PubMed1988

Hypocalcemia due to osteoblastic metastases and diminished parathyroid reserve in a patient with advanced breast cancer.

Symptomatic hypocalcemia is an uncommon finding in patients with malignant tumors. A patient with advanced breast cancer is described, who developed severe hypocalcemia in the course of her disease. The hypocalcemia was caused by the combination of enhanced calcium need due to progression of osteoblastic metastases and diminished parathyroid reserve due to tumorous infiltration of the parathyroid glands.

Bone Neoplasms↗
PubMed1987

[Poikilothermy].

Explore the source record for details and available documents.

Adolescent↗
PubMed1987

Role of proaggregatory and antiaggregatory prostaglandins in hemostasis. Studies with combined thromboxane synthase inhibition and thromboxane receptor antagonism.

Thromboxane synthase inhibition can lead to two opposing effects: accumulation of proaggregatory cyclic endoperoxides and increased formation of antiaggregatory PGI2 and PGD2. The elimination of the effects of the cyclic endoperoxides by an endoperoxide-thromboxane A2 receptor antagonist should enhance the inhibition of hemostasis by thromboxane synthase blockers. We have carried out a series of double-blind, placebo-controlled, crossover studies in healthy volunteers to check if this hypothesis may be operative in vivo in man. In a first study, in 10 healthy male volunteers, the combined administration of the thromboxane receptor antagonist BM 13.177 and the thromboxane synthase inhibitor dazoxiben gave stronger inhibition of platelet aggregation and prolonged the bleeding time more than either drug alone. In a second study, in 10 different healthy male volunteers, complete inhibition of cyclooxygenase with indomethacin reduced the prolongation of the bleeding time by the combination BM 13.177 plus dazoxiben. In a third study, in five volunteers, selective cumulative inhibition of platelet TXA2 synthesis by low-dose aspirin inhibited platelet aggregation and prolonged the bleeding time less than the combination BM 13.177 plus dazoxiben. In vitro, in human platelet-rich plasma stimulated with arachidonic acid, the combination of BM 13.177 and dazoxiben increased intraplatelet cAMP while the single drugs did not affect it. Our results indicate that prostaglandin endoperoxides can partly substitute for the activity of TXA2 in vivo in man and that an increased formation of endogenous antiaggregatory and vasodilatory prostaglandins, as obtained with selective thromboxane synthase inhibitors, may contribute to the impairment of hemostasis.

Adult↗
PubMed1986

The role of epinephrine in the circulatory effects of coffee.

The circulatory response to coffee was studied in 10 normotensive, 10 bilaterally adrenalectomized, and 10 hypertensive subjects. In the normotensive group, drinking coffee exerted a rise in blood pressure (+5.1/+11.5 mm Hg), a fall in heart rate (-6.0 bpm), a rise in plasma epinephrine (+257.2%), and no change in plasma norepinephrine. The response to coffee in the hypertensive group was similar or even enhanced. In the patients who had undergone adrenalectomy, the coffee-induced rise of diastolic blood pressure was attenuated (+7.9 mm Hg; P less than 0.05), whereas plasma norepinephrine showed a fall (-20.8%) and plasma epinephrine remained undetectable throughout all tests. Additionally, a fall of plasma renin activity after coffee was observed in all three groups. We conclude that the pressor response to coffee is not purely a result of circulating epinephrine or to stimulation of the renin-angiotensin-aldosterone system. On the other hand, the coffee-induced increase of plasma epinephrine may increase the pressor response to coffee.

Adrenalectomy↗
PubMed1985

Cerebrospinal fluid rhinorrhea during treatment with bromocriptine for prolactinoma.

A 47-year-old man exhibited loss of libido and impotence in association with plasma hyperprolactinemia and a pituitary mass with downward extension of the tumor to the sphenoid sinus and to the suprasellar cisterns. Bromocriptine, 15 mg daily, reduced the hyperprolactinemia as well as tumor size. After 8 months on this therapy, the patient developed overt CSF liquorrhea. Five days after discontinuation of bromocriptine, the CSF rhinorrhea stopped, and when bromocriptine was given again 2 weeks later, CSF rhinorrhea returned within 3 days. We believe this phenomenon to be due to retraction of tumor by bromocriptine exposing a defect in the sella floor. Transient occurrence of CSF rhinorrhea can be considered as a consequence of tumor regression in patients on bromocriptine. The possibility of this complication, especially in patients with downward extension of tumor, should be noted.

Bromocriptine↗
PubMed1976

[Hydatid cyst of the lung (author's transl)].

The authors, in an international collaborative study, report on 257 cases of operated hydatid cysts. The delicate choice between resection and conservative treatment depends on a protocole and/or on experience: in the large series published in the last 10 years the rate of resections has varied between 43 and less than 20 per cent. Cure of the pulmonary hydatid cyst, be it live or ruptured, is presently a well systemized, efficient and safe operation. The authors present their data that correlate well the sparse literature related to the subject in the last decade.

Adolescent↗