11C-metomidate positron emission tomography after dexamethasone suppression for detection of small adrenocortical adenomas in primary aldosteronism.

PURPOSE: To evaluate whether dexamethasone suppression treatment can improve (11) C-metomidate positron emission tomography (MTO-PET) detection of small adrenocortical adenomas in primary aldosteronism (PA). MATERIALS AND METHODS: Eleven patients with proven PA and two patients with non-hyperfunctioning adrenocortical incidentalomas and small adrenocortical tumours observed on CT underwent MTO-PET before and 3 days after administration of oral dexamethasone suppression treatment. Small "hot-spot" regions of interest comprising 4 pixels (SUVhs) and 1 pixel (SUVmax) were placed in the tumour area with the highest radioactivity concentration and their respective standardised uptake values (SUV) were recorded. RESULTS: All tumours were detected and categorised as adrenocortical by MTO-PET. SUVhs as well as SUVmax were higher in PA compared to nonfunctional adenomas. Normal adrenal cortex was suppressed after dexamethasone (p < 0.05), but tumour SUV was not significantly decreased after suppression in either PA or nonfunctional tumours (p > 0.05). However, these changes caused no significant increase in the tumour-to-normal adrenal ratio (p > 0.05). CONCLUSION: MTO-PET is a highly sensitive method for detecting and categorising even small adrenocortical tumours in PA. In this series, dexamethasone-suppressed MTO-PET was unable to increase the tumour-to-normal adrenal ratio to further facilitate detection of small adenomas in PA as an alternative to adrenal venous sampling.

Long-term effects of surgical correction of adrenal hyperplasia and adenoma causing primary aldosteronism.

PURPOSE: The purpose of this is to study long-time results of surgery for primary aldosteronism. MATERIALS AND METHODS: Thirty patients operated on for primary aldosteronism were followed for an average of 7 years. All but five required potassium substitution. Systolic as well as diastolic hypertension (mean 157/93 mmHg) was present necessitating one to five antihypertensive drugs daily (mean 2.33). Preoperative indications for surgery included presumed adenoma (aldosterone-producing adenoma (APA)) or in one case unilateral dominance of hyperplasia. RESULTS: Histopathology was classified into adenoma (n = 9), dominant nodule (n = 16), and general hyperplasia without dominating nodules (n = 5), demonstrating a higher frequency of hyperplasia than anticipated. Long-term results revealed well-controlled blood pressure (BP; mean 134/80 mmHg). Antihypertensive medication was reduced (average of 1.78 per day), but only 36% of the patients were taken off these drugs completely. S-Aldosterone was normalized. All but one (a recurrence) were normokalemic without potassium substitution at follow-up. The APA group needed less medication (median 0.5 vs. 1.5 and 2 per day) and more patients in this group were totally medication free (50%). Two recurrences occurred in the group with general hyperplasia without dominating nodules. CONCLUSION: Nodular hyperplasia is more common than anticipated. Hypersecretion of aldosterone may be released from a large nodule identified as an adenoma, as well as from a generally hyperplastic gland that has not been identified as such. Nevertheless, surgery for lateralized disease results in good long-term control of BP with less antihypertensive medication. However, patients with dominant nodule or general hyperplasia without dominating nodules need more postoperative treatment than patients with APA. The majority of patients do not achieve normotension without medications, but they do become normokalemic.

Reduced food intake after jejunoileal bypass: a possible association with prolonged gastric emptying and altered gut hormone patterns.

The object of this study was to examine whether eating behavior, food preference, gastric emptying, and gut hormone patterns are altered after jejunoileal bypass (JIB) in patients with severe obesity. Eight obese [mean (+/- SD) body mass index (BMI; in kg/m2) 42.9 +/- 4] subjects were studied prospectively before and 9 mo after JIB with eight age- and sex-matched normal-weight control subjects. Total energy intake, data from the universal eating monitor (VIKTOR), eating motivation measured by visual analog scales, a food-preference checklist, a forced-choice list, solid-phase gastric emptying, and postprandial concentrations of cholecystokinin, motilin, and neurotensin were studied. BMI was reduced by 29% after JIB. Compared with normal subjects, the JIB patients showed a reduced desire to eat, decreased hunger, and reduced prospective consumption before a test meal. After surgery, obese subjects selected fewer food items and showed a reduced preference for high-carbohydrate and high-fat items before a test meal. There was a trend from an accelerated toward a decelerated eating pattern in obese subjects after JIB. After JIB, gastric emptying of obese subjects was slowed and similar to that in control subjects. Obese subjects had lower postprandial cholecystokinin concentrations that were lower than those of control subjects both before and after JIB. Postprandial concentrations of neurotensin were higher after JIB. We conclude that after JIB, the desire to eat and preference for high-carbohydrate and high-fat items is reduced, resulting in decreased energy intake. That gastric emptying is prolonged and gut hormone patterns are altered with low postprandial plasma cholecystokinin and high neurotensin plasma concentrations may at least partly account for these observations.

Fibromuscular dysplasia of the renal artery--management and outcome.

Fifty-seven patients (48 women, 9 men) with fibromuscular dysplasia (FMD) of the renal artery were investigated. Mean age at detection of hypertension was 37 years. The diagnosis was established by angiography. Patients with lateralization of renin secretion to the stenotic side had a significantly higher peripheral renin level than those without. The patients were initially treated with surgery (n = 19), percutaneous transluminal renal angioplasty (PTRA) (n = 9), or pharmacologically (n = 29). During a mean follow-up period of 6.2 years, thirteen pharmacologically treated patients were transferred for surgical treatment or PTRA, because of progression of the FMD or inadequate blood pressure control. The long-term effect of surgery (n = 22) on the blood pressure was satisfactory in 91% and that of PTRA (n = 18) in 55%. The low success rate after PTRA seems to be due to an inappropriate selection of patients. Age, duration of hypertension and renal vein renin ratio seem to be important prognostic factors for the outcome of surgery or PTRA.

Role of surgery in infective endocarditis.

One-hundred-and-thirteen patients with endocarditis and valvular insufficiency were studied retrospectively with special regard to indications for operation and the optimum time for cardiac valve surgery. Thirty patients (group I) had acute, 63 (group II) subacute and 20 (group III) prosthetic valve endocarditis. Group I: Eleven patients underwent surgery in the acute stage, 8 while bacteremic; 5 of the latter died perioperatively. Of the 19 patients treated medically, 16 died. Group II: All patients underwent operation in a bacteria-free state. The mortality was 5%. Group III: Eight patients had early (less than 60 days postoperatively) and 12 late endocarditis. Total mortality was 40% (71% early and 25% late mortality). Ten patients underwent reoperation, with a mortality of 20%, compared with 60% in the medically treated group. The results support the indication for early operation in acute endocarditis with progressive cardiac failure and renal failure and prosthetic valve endocarditis, even during bacteremia.

Progressive fibromuscular dysplasia of the renal artery. Angiographic and clinical follow-up.

Eight patients with unilateral and 12 patients with bilateral fibromuscular dysplasia of the renal arteries were re-examined after 3 to 11 (mean 6) years. Angiographic progression was evaluated in a score system and occurred in 19 of the 20 patients, 83 per cent had progression on the right and 54 per cent on the left side. The most frequent indications of progressive disorder were increase in the length of the lesion and the number of membraneous stenoses. Less sensitive was the determination of least luminal diameter, mainly due to difficulties in measuring this in the majority of cases. Nine of the patients had clinical progression of hypertension. These patients did not differ in angiographic score from the 11 without such progression. Because of the progressive nature of the disease and the existing problems to evaluate the hemodynamic significance of fibromuscular dysplasia, a frequent use of percutaneous transluminal angioplasty is recommended.

Percutaneous transluminal renal artery dilatation for fibromuscular dysplasia with special reference to the acute effects on the renin-angiotensin-aldosterone system and blood pressure.

Twelve hypertensive patients (mean age 46.6 years, range 37-55 years) with fibromuscular dysplasia of the renal artery were treated with percutaneous transluminal renal angioplasty (PTRA) and the effects on the renin-angiotensin-aldosterone system and blood pressure were studied in the acute phase. The technical result of PTRA measured by angiography and reduction of PRA and aldosterone excretion was satisfactory in 11 patients. In spite of this only three patients were cured of their hypertension and two patients were improved at six months follow-up. During PTRA an immediate rise in plasma renin activity was noted in patients without beta-receptor blockade but not in patients treated with beta-receptor blocking agents suggesting a beta-receptor mediated release. This peak in renin release was not accompanied by any rise in systemic blood pressure. The blood pressure response in the acute phase did not show any regular pattern. We conclude that PTRA can serve as a model for studying effects of 'clamping' and 'declamping' of the renal artery in man.