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B Nonnast-Daniel

Publications and source records attributed to B Nonnast-Daniel.

35 records · Page 2Linked to original sources
PubMed1990

Skin microcirculation and regional peripheral resistance in patients with chronic renal anaemia treated with recombinant human erythropoietin.

Skin microcirculation and regional peripheral resistance were studied in 14 patients with renal anaemia during therapy with recombinant human erythropoietin. Haematocrit was raised from 20.0 to 31.3% after 10-12 weeks of treatment and remained stable over another period of 12 weeks. Antihypertensive treatment had to be intensified in five patients. Regional calf blood flow decreased significantly; accordingly, calculated peripheral vascular resistance was increased by more than 100%. However, transcutaneous oxygen pressure (37 degrees C and 44 degrees C) increased significantly. The pathological vasoconstrictor response of skin capillaries was not influenced. There were no significant differences of any parameter between the patients requiring reinforced antihypertensive therapy and those with stable blood pressure. In conclusion skin oxygenation may be improved by erythropoietin treatment to a large extent despite an increase in calculated total limb vascular resistance.

Adult↗
PubMed1990

Two years experience of daily self-administered subcutaneous erythropoietin.

Recombinant human erythropoietin (EPO) has been used for 4 years in end-stage renal disease patients, administered intravenously 3 times a week. A study was undertaken to determine the optimal way of administration comparing 3 times weekly intravenous EPO to self-administered daily subcutaneous EPO (SADSCEPO). In a first group of 4 patients, we demonstrated that the change from 3 times weekly intravenous EPO to SADSCEPO permitted a dose reduction of 70%. In a second group of 20 patients who started the EPO therapy with the daily subcutaneous route at a median dose of 12 U/kg/day, the hematocrit increased from 20 to 30% in 4 months and remained over 30% in spite of a median dose reduction to 9 U/kg/day. The patients' acceptance of SADSCEPO was good. The mechanism allowing such a dose reduction is unknown. However, the significant reduction in median dosage requirement with the subcutaneous route should allow a greater number of patients to be treated more cost-effectively.

Adult↗
PubMed1990

Adverse cardiovascular effects of partial correction of renal anemia by recombinant human erythropoietin.

The analysis of the hemodynamic parameters involved in the regulation of blood pressure during correction of anemia shows - although peripheral resistance and cardiac output behave qualitatively as in the nonuremic patient - that the extent of change may be inadequate resulting in an increased blood pressure. The underlying mechanisms are not yet fully understood but to a greater part may be related to preexisting pathology due to a history of long-lasting hypertension. To avoid cardiovascular complications under rhEPO therapy the following should be considered: patients with a history of hypertension, even if they are normotensive in the anemic state, are at a higher risk for developing hypertension under rhEPO. Hypertensive complications may be rare events when anemia is corrected slowly. Further studies will demonstrate whether in addition to the benefit of a very low maintenance dose of rhEPO subcutaneous administration will also contribute to the reduction of the incidence of hypertension.

Anemia↗
PubMed1989

Specific imaging of dialysis-related amyloid deposits using 131I-beta-2-microglobulin.

Dialysis-related amyloidosis (DRA), characterized by its association with beta 2-microglobulin (beta 2m), has become a major concern in long-term hemodialysis patients. Hitherto the diagnosis was based on histological examinations of tissue obtained by biopsy or during surgery. In this preliminary study a new noninvasive diagnostic method was developed using the affinity of beta 2m for its derived fibrils. 3 patients on long-term hemodialysis for 10-16 years with biopsy-proven DRA and 1 patient on chronic hemodialysis for only 6 months were examined after intravenous injection of 131I-labelled beta 2m. Specific local accumulation of radioactivity was noted in the DRA patients after 48 h, persisting for further 96 h and corresponding to clinically or radiologically evident sites of amyloid deposition and to several other hitherto unsuspected sites. Examination of an excised amyloid tumor subsequent to in vivo labelling confirmed a highly specific accumulation of radioactivity in the amyloid tissue but not in control tissue. In the patient on chronic hemodialysis for only 6 months, no specific local accumulation was detected even after 1 week. These findings provide in vivo evidence in man that a specific uptake of circulating amyloid precursor molecules into deposits occurs and that this uptake may be used to radiolabel even small tissue infiltrates of amyloid. This method therefore may not only allow an objective, noninvasive detection of DRA but may also be used to obtain new pathophysiologic insights into amyloid formation in man, as well as permitting the evaluation of preventive therapeutic strategies in prospective studies on new patients.

Amyloidosis↗
PubMed1989

Subcutaneous amyloid-tumor of beta-2-microglobulin origin in a long-term hemodialysis patient.

beta 2-Microglobulin (beta 2M)-derived amyloidosis has become a major concern in long-term hemodialysis patients. Clinical symptomatology is largely restricted to the articular and periarticular sites and in rare cases systemic manifestations have been described. We present a long-term hemodialysis patient, who after 16 years of hemodialysis with regenerated cellulosic membranes not only had a bilateral carpal tunnel syndrome, cystic bone translucencies and humeroscapular periarthritis but also developed two subcutaneous tumors in both gluteal regions, causing discomfort when sitting. Histology, immunohistology and electron microscopy of the tumor from the right side showed that it consisted of beta 2M-derived amyloid with concurrent scattered amyloid infiltration of the overlying skin. This report therefore adds a new clinical manifestation to the symptomatology of this type of amyloid.

Amyloidosis↗
PubMed1989

Hemodynamics in hemodialysis patients treated with recombinant human erythropoietin.

The available data from experimental and clinical studies suggest that in the development of hypertension following correction of renal anemia under rhEPO three mechanisms are operative: (1) an increase in whole blood viscosity; (2) possible also a reduction of hypoxic vasodilatation, and (3) at least in some patients an inadequate reduction of cardiac output. To avoid cardiovascular complications under rhEPO therapy, the following should be considered: Patients that were hypertensive before the start of renal replacement therapy, even if they were normotensive in the anemic state - because of morphological alterations of their peripheral vascular bed-may run a higher risk for developing hypertension under rhEPO. As patients with undetected volume contraction may be more endangered by cardiovascular complications, the hematocrit should be monitored before and after dialysis, especially in patients with high weight gain and in children. Patients who are hypertensive under rhEPO therapy should be treated by antihypertensive drugs as appropriate. Drugs of the first choice are beta-blockers and vasodilating agents. Volume removal should not be the sole measure for blood pressure control and should be applied carefully. To avoid hypertensive and rheological complications, the target hematocrit should not exceed 30 vol%.

Anemia↗
PubMed1988

[Erythropoietin and hypertension].

Recombinant human erythropoietin (rhEpo) has been demonstrated in several studies to be effective in correcting the anemia of regular dialysis patients. This was accompanied by a significant improvement of the physical work capacity shown by exercise testing. The main side effect of rhEpo treatment has been the development or aggravation of hypertension in approximately 30% of the treated patients. In 2% hypertensive encephalopathy and convulsions occurred. Data obtained by measurements of regional blood flow indicate the peripheral resistance did increase probably due to rise of blood viscosity and reversal of preexisting hypoxic vasodilatation. To avoid hypertensive complications anemia should be corrected slowly over a period of 12-16 weeks. Target hematocrit should not exceed 30-35 vol. %. Blood pressure and volume status should be monitored closely.

Anemia↗
PubMed1988

Left atrial spontaneous echo contrast in mitral valve disease: an indicator for an increased thromboembolic risk.

The incidence of left atrial spontaneous echo contrast was evaluated in 52 patients with isolated or predominant mitral valve stenosis (Group 1) and 70 other patients who had undergone mitral valve replacement (Group 2). All patients were studied by conventional transthoracic and transesophageal two-dimensional echocardiography. Spontaneous echo contrast could be visualized within the left atrium in 35 Group 1 patients (67.3%) (including 7 patients with sinus rhythm) and 26 Group 2 patients (37.1%) (all with atrial fibrillation). Patients with spontaneous echo contrast had a significantly larger left atrial diameter and a greater incidence of both left atrial thrombi and a history of arterial embolic episodes than did patients without spontaneous echo contrast. Association between spontaneous echo contrast and left atrial thrombi and a history of arterial embolization (considered individually or in combination) showed a high sensitivity and negative predictive value. It is concluded that spontaneous echo contrast is a helpful finding for identification of an increased thromboembolic risk in patients with mitral stenosis and after mitral valve replacement.

Adult↗
PubMed1988

Effect of treatment with recombinant human erythropoietin on peripheral hemodynamics and oxygenation.

Slow progressive improvement of renal anemia from 21 up to 33% hematocrit by rhEPO treatment results in an increase of tissue oxygenation as indicated by a rise of the transcutaneous oxygen pressure. In normotensive patients this was accompanied by an increase in MAP (delta 6 mm Hg) within the normal range and a significant fall of the regional blood flow. These hemodynamic changes are caused by increases of the regional and presumably also of the total peripheral vascular resistance. Most likely the increase in total peripheral vascular resistance represents an autoregulatory event triggered by the rising tissue oxygenation. From the present data it is difficult to estimate to what extent the observed rise in hematocrit affects peripheral vascular resistance also via an increase of blood viscosity.

Adult↗
PubMed1987

Renal infarction with fatal bleeding--an unusual complication of Candida albicans endocarditis.

A patient with mitral valve endocarditis due to Candida albicans infection is presented. Because of persistent fever and one episode of transient right-sided hemiparesis, the patient underwent mitral valve replacement. Two weeks after successful valve replacement, the patient suddenly developed acute abdominal pain and died before a surgical intervention could be initiated. Autopsy examination revealed a renal infarction in the lower part of the right kidney with a large rupture of the capsule and retroperitoneal bleeding. A myocotic aneurysm could not be detected. The clinical significance of renal infarction in infective endocarditis is discussed.

Adult↗
PubMed1984

Is renal involvement a prognostic parameter in patients with infective endocarditis?

Renal involvement (RI)--defined as proteinuria greater than 150 mg per 24 h with haematuria or impaired glomerular filtration rate--was studied in 80 patients with infective endocarditis (IE). Proteinuria was measured quantitatively and further differentiated by the SDS-polyacrylamide-gel electrophoresis. RI was found in 40 patients (50%) with proteinuria from 150 to 8000 mg per 24 h. SDS-PAGE revealed a tubular protein pattern in 17 patients, a glomerular pattern in 6 and a glomerulo-tubular pattern in 17. Mortality rate was significantly higher in patients with RI (40%) than in those without (7.5%), and was not related to the type of infected valve, infective organisms, method of treatment (surgical or medical) or embolic events. Following successful treatment of IE, 18 out of 23 patients showed complete normalization of renal function. Renal involvement in patients with IE may be of prognostic significance--indicating an impaired prognosis.

Adolescent↗