RESUMEN

We studied three patients with proximal tubulopathy characterized by defective reabsorption of phosphate, glucose, amino acids, urate, and low molecular weight proteins. This tubulopathy differs from Fanconi syndrome in that the patients had normal plasma bicarbonate and absorptive hypercalciuria associated with increased 1,25-dihydroxyvitamin D levels. The youngest patient was rachitic and may be classified with previously described patients, whereas the other two patients presented with nonrachitic osteopenic bone disease and their tubulopathy started during adult life. Kidney defects appeared sequentially in one of the nonrachitic patients. The two brothers of the youngest patient had similar kidney and bone disturbances. One of the other two patients had a brother with similar kidney reabsorption defects; an additional brother was probably affected and a sister presented with glycosuria, but no other reabsorption defects. The findings in these two families suggest a genetic transmission of proximal tubulopathy. The third case was sporadic. Renal histology of the three patients showed a great number of giant cells in the tubular lumen. We conclude that, at least in our adult patients, tubulopathy may represent a new entity among the proximal tubular dysfunction cases described to date. The features of this proximal defect suggest that it may be caused by a selective alteration of luminal cell membrane transport of phosphate, glucose, amino acids, urate, and proteins in the presence of a normal sodium gradient across the tubular cell membrane.

Asunto(s)

RESUMEN

On the basis of previously described effects of recombinant human erythropoietin (rhEPO) treatment on endocrine abnormalities present in uremia, we assessed the possible effect of treatment with rhEPO on growth hormone (GH) response to growth hormone releasing hormone (GHRH) in a group of uremic patients. Eight patients on maintenance hemodialysis for 12 to 228 months, not previously treated with rhEPO, were tested with 100 micrograms of GHRH i.v. in bolus before and after three months of rhEPO treatment (40 U/kg i.v. three times a week). Before treatment, the GH response to GHRH was characterized, in uremic patients, by remarkable differences in plasma GH values and in the pattern of response curve in single patients. The variability of GH response was not modified after rhEPO treatment; however, an overall potentiation of GH response with a significant increase of plasma GH (p = 0.017 at 15 min, p = 0.035 at 30 min after GHRH injection) was observed in the tests performed after treatment. rhEPO administration induced an evident improvement of anemia, blood hemoglobin concentration being 5.3-7.6 g/dl before and 9.1-11.3 g/dl after treatment; however a demonstrable correlation between the potentiation of GH response to GHRH and the increase of hemoglobin concentration was not observed.

Asunto(s)

RESUMEN

The effects of acute changes in cardiac volumes determined by hemodialysis on cardiac voltages were assessed in 18 chronically uremic patients by means of a vectorcardiographic and scalar Frank leads recording, immediately before, at the 90th and 180th minute, and immediately after hemodialysis. The following parameters were simultaneously monitored: body weight, systolic and diastolic blood pressure, heart rate, hematocrit and, in eight patients, echocardiographic systolic and diastolic diameters of the left ventricle. During hemodialysis all voltages considered except R wave in X lead increased significantly. They were inversely correlated with body weight, blood pressure, and systolic and diastolic diameters and directly with hematocrit (volemia-dependent parameters). The maximal vector on the left sagittal plane and the R wave amplitude in Z lead, representing left ventricular posterolateral wall activation, showed the greatest increase. When, at the end of hemodialysis, an amount of fluids ranging from 300 to 800 ml was restored, these cardiac voltages decreased paralleling the increase of left ventricular diameters. In conclusion, these results demonstrate that cardiac voltage and volumes are inversely related.

Asunto(s)

Asunto(s)

RESUMEN

For the purpose of assessing the cardiovascular effects of hemodialysis (HD), M-mode echocardiography was performed 24 hours before and 2 hours after this procedure in 15 patients with chronic renal failure. The results, which include computer analysis of digitized interventricular septum (IVS) and left ventricular posterior wall (LVPW), show the following statistically significant changes after HD: reduction of end-diastolic and end-systolic internal diameters of the left ventricle (LVID), increase of mean velocity of circumferential fiber shortening, of peak rate of systolic and diastolic LVID variation, of systolic and diastolic LVPW movement, and of IVS movement in systole. These results demonstrate that after HD the left ventricle not only decreases in size but also its performance improves in both contraction and relaxation. These changes did not correlate with the reduction in body weight and arterial pressure following HD; hence HD seems to act on left ventricular function by reducing mainly afterload and, possibly, by modifying some humoral parameters. In conclusion, M-mode echocardiography, especially when utilized in conjunction with the computerized analysis of the recordings, is useful and reliable in monitoring hemodynamic changes occurring during the dialytic session.

Asunto(s)

RESUMEN

The possibility that some hereditary factors favoring the development of 'essential' hypertension in man may act through modification of kidney function was evaluated in a retrospective study of 36 renal transplant recipients followed for 1 year. The patients were divided into two groups of 18 subjects each, matched for age, sex, body surface area, familial hypertension, duration of hemodialysis before transplantation and original kidney disease. In the first group, at least one of the donor's parents was hypertensive and in the second group all the members of the donor's family were normotensive. Plasma creatinine, daily dose of prednisone, number of rejection episodes and blood pressure were almost the same in both groups, but the requirement for antihypertensive therapy was significantly greater in the first group during the first 4 months after transplantation (p less than 0.05). Therefore, it seems reasonable to consider that there is some influence of familial existence of hypertension on the renal pressure regulatory mechanisms.

Asunto(s)

RESUMEN

To define the effect of different immunosuppressive treatments on survival of long-term kidney transplant recipients, we have followed, for a period of four years, a group of 18 long-term survivors (more than three years) of kidney transplantation who were subjected to two different corticosteroid regimens (daily or alternate day corticosteroids) plus azathioprine. THis study not only confirms that an alternate day corticosteroid treatment reduces the incidence of infectious episodes and of side effects, but also suggests that it may steadily improve the survival of these patients. One of the six patients who performed an alternate day corticosteroid regimen died and only one lost renal graft function. On the contrary, three of the twelve patients who received daily corticosteroids died of causes related to immunosuppressive treatment, while another five patients lost renal graft function. A very low level of peripheral blood lymphocytes, of early E rosette and E rosette-forming cells was detected in patients who died of causes related to immunosuppressive treatment.

Asunto(s)

RESUMEN

The role of steroids, and specifically of methylprednisolone, in the pharmacological treatment of cadaver kidney transplants is discussed. The action mechanisms of the substance, and the modalities for its use in basic treatment of the transplanted organ and in rejection crisis are described. Finally, the results obtained in 147 transplanted patients, the complications involved and the measures taken to eliminate, or at least reduce, the problems of prolonged steroid therapy are reviewed.

Asunto(s)

RESUMEN

In 36 subjects in chronic hemodialysis treatment and in 36 patients with a renal transplant, well functioning for more than one year, the ocular complications related to the specific form of treatment were evaluated and compared. In the group of the dialyzed subjects ocular pathology was composed by: lens opacities in 9 cases, corneal calcifications in 7 cases, hypertensive fundus in 8 cases. In no patient these lesions produced measurable visus reductions. In the transplant group ocular pathology was composed by: lens opacities in 28 patients, hypertensive fundus in 7 and intraocular hypertension in one. One case of herpes cheratytis and one case of endophtalmytis have also been observed. In 9 patients these lesions produced a remarkable visus reduction. In conclusion renal transplantation shows a greater incidence of ocular complications if compared to hemodialysis. This situation has not important consequences on the rehabilitation of the transplanted subject for the possibility of surgical correction of the cataract.

Asunto(s)

RESUMEN

Bone scintigraphy with 99mTc-diophosphonate and a whole body scanner was performed on 18 subjects with good renal function who had received a kidney transplant more than six months previously. This demonstrated scintigraphyc abnormalities in 17 of the cases. The alterations were characterized in 44,5% of the cases by focal uptake of the tracer. Diffuse alterations were observed in 4 of the 18 cases studied (22%). In these patients increases of serum alkaline phosphatase and in PTH levels were present. Ca++ exchangeable pool values and accretion rate were normal in the subjects with focal lesions. In the cases where scintigraphy showed diffuse lesions both the above parameters were much increased.

Asunto(s)

Asunto(s)

RESUMEN

This paper evaluates the cellular immune system of 16 cadaver kidney transplant recipients more than three years after transplantation. The number and percent of active E rosette forming cells, of E rosette forming cells and of IgG and IgM bearing lymphocytes were determined; the blastogenic response of peripheral blood lymphocytes to PHA and PWM was studied in homologous and autologous serum. Significant alterations of the tests performed were found in patients who had undergone kidney transplant, suggesting a pathogenetic role of chronic immunosuppressive therapy but not excluding other possible factors.

Asunto(s)

Asunto(s)

Asunto(s)

Asunto(s)

Asunto(s)

Asunto(s)

Asunto(s)

Asunto(s)

Asunto(s)