Search PubMed⌕ Search

Biomedical subjects

M Labeeuw

Publications and source records attributed to M Labeeuw.

At least 73 records · Page 4Linked to original sources

Acute renal effects of beta-blockers.

The effects on renal function of a single dose of six different beta-blockers (atenolol, propranolol, metoprolol, acebutolol, nadolol, and pindolol) have been evaluated in 51 hypertensive patients with normal glomerular filtration rate (GFR). Most drugs, except pindolol, induce a 10-20% decrease in GFR and renal plasma flow, although differences in the magnitude and the pattern of this fall are evident. The fractional excretion of sodium is generally depressed by 20-40%. These data suggest a limited renal tolerance of most beta-blockers during acute administration, irrespective of their pharmacological characteristics.

Adrenergic beta-Antagonists↗

Surgical versus medical treatment in renovascular hypertension. Retrospective study of 166 cases.

A retrospective study of 166 cases of renovascular hypertension was performed. Before 1979, 114 patients were treated for renovascular hypertension. Forty underwent surgery. In this group, therapy resulted in cure or improvement in 45% of the patients. Seventy-four patients underwent medical therapy: 88% of these patients had improvement of blood pressure when beta-blockers were used, but only 41% when they were not. More recently (from 1979 to 1983), 52 patients were treated for renovascular hypertension, of which 31 patients have been operated for fibromuscular renal artery stenosis (62%) or atherosclerotic renal artery stenosis (32%). In this group, 90% of the patients were considered to be cured or improved with a mean follow-up of 36 months. Eighteen of thirty-one patients underwent autotransplantation with satisfactory results on blood pressure control. Twenty-one patients were treated by antihypertensive drugs: 86% of the patients were improved or cured (71.5% of the patients had atherosclerotic lesions) with a mean follow-up of 46.8 months.

Adult↗

[Course of renal function in malignant hypertension. Effect of treatment. Study of 30 cases followed for 5 to 18 years].

Renal insufficiency is the most frequent complication of malignant hypertension (MHT). The initiation of effective hypotensive treatment is generally followed by a rapid improvement of renal functions, but the long-term evolution has been only rarely studied. A group of 30 patients was retrospectively selected on the following criteria: Malignant hypertension: mean DBP 138 +/- 20 mmHg, hypertensive retinopathy stage III-IV; Early renal insufficiency: mean Inulin clearance (CIN) 66 +/- 26 ml/min, mean PAH clearance (CPAH) 364 +/- 161 ml/min; Clinical and functional follow-up ranging from 5 to 18 years. Among these patients, two groups were defined according to the quality of BP control: good or fair responders (GR) with a DBP always less than 110 mmHg, poor responders (PR) with a DBP occasionally greater than or equal to 110 mmHg. The results show in the two groups an improvement of CIN at 3 years, followed by a stabilization then a decrease after the 6th year. However the early improvement is significantly lower in PR. Despite similar initial values (GR = 54.7 +/- 31.3; PR = 51.4 +/- 13.2), CIN remains always lower in PR (at 9 years = GR 72.4 +/- 30.6; PR 56.0 +/- 19.8). During the first 3 years, CPAH increases in GR, whereas it decreases in PR, resulting in significantly different values at 3 years. At 9 years, CPAH remains improved in GR (329.1 +/- 109.3 vs 281.7 +/- 173.8 initially) but decreased in PR (256.0 +/- 166.9 vs 307.3 +/- 119.5 initially). The parallel improvement of CIN and CPAH in GR confirms a favorable effect of BP control on early vascular lesions.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Recurrent myalgias associated with cimetidine.

A chronically hemodialyzed patient experienced recurrent episodes of myalgia while on cimetidine treatment (400 mg/day). After two uneventful courses of cimetidine, the pain appeared at the end of a third fourteen-weeks long course. Severe myalgia occurred at the sixth week of a fourth exposure to cimetidine. Pain was predominant in the hip area, disappeared within a few days after withdrawal and recurred three weeks after resuming therapy. There was no sign of neurological involvement and CPK remained consistently normal. Ranitidine was subsequently administered for four months whereby the patient showed no symptoms of myalgia. This observation suggests that, in susceptible individuals, a progressive decrease in tolerance to cimetidine might occur with repeated courses.

Cimetidine↗

Hypercalcemia in 25 OH D3 treated patients receiving a calcium exchange resin.

Seven patients with advanced renal failure, six of whom were dialysed, received a cation exchange resin in the calcium cycle because of severe hyperkalemia, together with their usual preventive treatment of renal osteodystrophy, including 25 hydroxycholecalciferol. Hypercalcemia developed in four subjects within less than thirty days and disappeared within four days following the withdrawal of the resin. Patients who exhibited hypercalcemia had higher calcium intake, lower predialysis blood calcium and higher PTH values before introduction of the treatment. Three of the four hypercalcemic patients were diabetics. It is therefore advised to frequently monitor blood calcium when using calcium exchange resin in patients treated with vitamin D analogs.

Calcifediol↗

[Diagnosis of relative hypomagnesurea in calcium lithiasis: reference values for a new parameter].

In calcium stone formers, the ratio of urinary magnesium concentration to urinary calcium concentration (Mg/Ca) is used to express the already reported low Mg excretion relatively to Ca excretion. However the Mg/Ca value depends on the Ca excretion rate, decreases after oral Ca load and is not directly related to Mg excretion. Therefore when studying patients with different Ca excretion rates, or when performing an oral Ca load, Mg/Ca is not directly useful to express a relative hypomagnesuria. We established a new parameter from the normal relationship between urinary Mg and Ca excretion rates. Its value is above - .065 in 97.5% of 99 control urinary samples. It is stable for any studied Ca excretion rate, including post Ca load excretion rates, and is highly correlated with Mg excretion rate. This parameter allows for the accurate diagnosis of relative hypomagnesuria in stone formers.

Adult↗

Ranitidine kinetics in chronic renal impairment.

The effects of moderate to severe renal impairment on kinetics of the H2-blocker ranitidine were investigated in 16 patients divided into two groups. Mean inulin clearance (ClIn) was 35 +/- 18.3 ml/min/1.73 m2 in group I and 7.4 +/- 3.5 ml/min/1.73 m2 in group II. Each patient received a single 150-mg oral dose of ranitidine. Values determined were maximum plasma concentration (MC) and time of occurrence, AUC, elimination t 1/2 (t 1/2 beta), total amount of unchanged ranitidine recovered in urine, and ranitidine renal clearance (ClR). MC values were higher and longer delayed than values reported in subjects with normal renal function. The t 1/2 beta was longer in group I and group II and correlated with the degree of renal impairment. The amount of ranitidine excreted within the first 24 hr decreased (18% of the dose in group I and 6% of the dose in group II), and ClR correlated strongly with ClIn, indicating that the observed changes in ranitidine kinetics are mainly related to changes in its renal excretion.

Adult↗

[Comparative effects on renal function of 4 beta-blockers injected intravenously].

Four beta-blockers: atenolol 15 mg i.v., metoprolol 25 mg i.v., acebutolol 45 mg i.v. and labetalol 50 mg i.v. were administered to 106 patients suffering from hypertension and with normal or disturbed renal function. During an identical test protocol, measurements of clearance of inulin, of PAH, urine sodium and the fraction of sodium excreted were recorded one hour before and four or five hours after administration of the antihypertensive. Mean blood pressure and heart rate were also recorded. The three pure beta-blockers reduced inulin and PAH clearance and lowered urine sodium. These modifications were the same for all three drugs. Labetalol, which also possesses alpha-blocking properties, did not reduce renal function values or urine sodium. While a slight fall in blood pressure occurred with all the antihypertensives, heart rate was reduced only by the three pure beta-blockers. The action of the four drugs was very similar whatever the state of the subject's renal function. The study of the renal effects of the beta 1-selective atenolol and metoprolol, and acebutolol which has a higher intrinsic sympathomimetic activity does not demonstrate any significantly different renal action among these three drugs, but the effects of labetalol on renal function values and urine sodium are slighter. The renal action of the beta-blockers cannot be fully explained. Though the fall in the renal plasma flow and in the glomerular filtration rate can be related partly to the decrease in the cardiac output consequent to induced bradycardia, stimulation of renal alpha-receptors must be considered.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenergic beta-Antagonists↗

The nephrotic syndrome in adults aged over 60: etiology, evolution and treatment of 76 cases.

A study of the clinical, etiological and histological features of the nephrotic syndrome occurring in 76 adults aged over 60 was performed. Membranous nephropathy was the most frequent type (40%). 32% of the cases of membranous nephropathy were associated with another disease which was a malignant one in 22% of the cases. In 2 cases a renal vein thrombosis was associated with the malignant disease. Amyloidosis appeared to be the most frequent cause of the secondary nephrotic syndrome (13%), and was often associated with plasma cell dyscrasia. The study also showed the importance of lipoid nephrosis among elderly patients with the nephrotic syndrome (20%). Amongst these cases it is necessary to consider the association of minimal changes with a systemic disease, and the histological diagnosis of focal hyalinosis. Indeed the presence in elderly patients of arteriolar, interstitial and glomerular lesions of hyalinosclerosis makes interpretation difficult. With corticosteroid therapy complete remission was frequent in patients with lipoid nephrosis.

Age Factors↗