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There are two aspects to considerations of the value of peritoneal dialysis (PD) in the treatment of renal insufficiency with associated pathology. The first involves the effects of the treatment on the symptoms or evolution of the pathology. Examples include the improvement of dyspnea due to cardiac insufficiency (CI) and of cirrhotic ascites (CA). However, there is also an undefined risk of reactivation lupus. The second facet is the increased risk of peritoneal infection, particularly for patients who are HIV + or who are immunosuppressed due to lupus or myeloma. In certain types of case (lupus with intractable vascular thrombosis, intolerance of ultrafiltration in cases of CI, AC or generalised amyloidosis) PD has particular advantages. Nevertheless, there has been no appropriate prospective study to demonstrate or otherwise the advantages in terms of survival. The use of PD remains therefore a matter of choice for individual patients and experienced health care team.

Central venous access is an important component of hemodialysis. New materials are presently available which, during the last years, have allowed for a long term use of central venous catheters (CVC). While patients with failing fistulas still represent the majority of cases, a growing number of patients are given CVC as a primary vascular access for hemodialysis. The experience is however too short and further studies should address the question of maintenance, as well as the cost-benefit ratio of such permanent CVC.

Still few data are available on efficacy and safety of recombinant erythropoietin (rEPO) in patients with myeloma and end-stage renal failure (ESRF); two such hemodialysed patients are reported in whom only partial response was observed, despite iron, folic acid supplementation and, in one case, high doses of rEPO (320 IU/kg/week). Despite improvement in well being and no need of further transfusion, hemoglobin did not reach 80 g/l. One patient developed recurrence 4 weeks after starting rEPO. Patients with ESRF and myeloma should benefit from rEPO but particular attention should be paid to marrow proliferation.

Diseases associated with renal amyloidosis were evaluated in 216 patients observed between 1956 and 1989. The percentage of secondary amyloidosis decreased from 72 to 47%, where it has remained for the past 20 years, despite the clear diminution in the tuberculosis rate; this is due to its increased incidence of association with rheumatoid diseases. Dysglobulinemia was found in more than 75% of the patients with AL amyloidosis. Amyloidosis associated with this dysglobulinemia, of which 30% were myelomatous, represented more than 25% of the cases observed during the past decade and constituted, with rheumatoid arthritis, the two most common etiologies.

The gammaglutamyl L-dopa (or gludopa), a dopamine (DA) prodrug, may be usefull in antihypertensive therapy as an orally active specific renal vasodilator. Indeed, gludopa is selectively metabolized in vivo by the kidney. This is the consequence of the sequential action of two renal enzymes, gamma-glutamyl transpeptidase (gamma-GT) and aromatic L-amino acid decarboxylase. The aim of this work was to elucidate, in vitro, the factors regulating its metabolism and to characterize its renal vascular effects. The rat kidney was isolated and perfused at constant flow in a closed circuit with a modified Krebs-Henseleit solution (BSA 6g/100 ml). Gludopa injection (10(-5) M) led to generation of DA (measured by gaz chromatography/mass spectrometry) in the venous effluent (134 +/- 39 ng/ml, n = 3) and in the urine (257 +/- 107 ng/mn/g). In non filtering kidneys, the level of DA in recirculating medium was depressed (47 +/- 5 ng/ml, n = 5; p less than 0.05). Glomerular filtration and access to the gamma-GT localized on the brush border membrane of proximal tubular cells are thus important for optimal metabolism of gludopa. Vascular effects of gludopa were studied on the isolated rat kidney after reestablishing vascular tone by continuous perfusion with prostaglandin F2 alpha (10(-8) M/mn) and after inhibition of alpha- and beta-adrenoceptors. Gludopa (3 X 10(-6) to 4 X 10(-5) M) induced dose-dependent renal vasodilation. At 4 X 10(-5) M, the renal response (30 +/- 3 p. 100 of the relaxation induced by 10(-4) M of papaverine) was similar to that elicited by DA at 20 fold lower concentration.(ABSTRACT TRUNCATED AT 250 WORDS)

Over the last 23 years, progress in renal transplantation has dramatically decreased mortality and transplant failures, especially during the first years following the transplant. Further improvement in immunosuppression or in induction of specific unresponsiveness should, in the future, limit the incidence of late failures. More experience in transplantation has led to reduced frequency and severity of most complications. This has resulted in acceptance of patients with risk factors such as old age or infancy, poor vascular status, hyperimmunization, or requirement for several transplants (kidney + pancreas, kidney + heart, kidney + liver, etc.). Optimum organ procurement facilities will be required to meet the increased demand for kidney transplants. It is hoped that this need will be stabilized when late transplant failures will become infrequent, thus decreasing the requirements for retransplantation.