D. Verbeelen

Acute tubulointerstitial nephritis and uveitis syndrome in the elderly.

A case of acute tubulointerstitial nephritis and uveitis syndrome (TINU syndrome) in an elderly woman is reported. The present case demonstrates that this entity originally observed in children, and more recently in adults, may also occur in the elderly. The aetiology and treatment are briefly discussed.

Biocompatibility of a 1.1 % Amino Acid-Containing Peritoneal Dialysis Fluid Compared to a 2.27% Glucose-Based Peritoneal Dialysis Fluid

The biocompatibility of a 1.1% amino acid-containing peritoneal dialysis fluid (AA-PDF) was compared to that of a 2.27% glucose-based peritoneal dialysis fluid (G-PDF). Peritoneal macrophages (PMO), isolated from the peritoneal dialysis (PD) effluents of 10 chronic ambulatory PD patients, were tested for their phagocytosis capacity and peak chemiluminescence response. A subset of PMO was cultured for 24 h with and without lipopolysaccharide (LPS) to study the release of interleukin-1 beta (IL-1 beta) and 8 (IL-8). As control, the interleukin release by blood monocytes of healthy donors was tested. The opsonic activity of the PD effluent was tested as well. Compared to PMO isolated from G-PDF, PMO from AA-PDF showed a significantly better phagocytosis capacity. There was no difference in the peak chemiluminescence response between PMO from AA-PDF and G-PDF. The release of IL-1 beta by unstimulated PMO isolated from the two fluids did not differ. Compared to control monocytes, however, PMO from both fluids showed a considerable spontaneous release of IL-1 beta. When stimulated with LPS, IL-1 beta production by PMO from G-PDF exceeded that of PMO from AA-PDF (p < 0.002). The release of IL-8 by PMO from G-PDF was significantly higher in comparison with PMO from AA-PDF, both spontaneously and after stimulation with LPS (p < 0.02). The opsonic activity of undiluted and to 75% diluted effluents was significantly higher for G-PDF than for AA-PDF (p < 0.01). Thus, compared to the regularly used G-PDF, the phagocytosis capacity as measure for PMO function seems to be better preserved after in vivo exposure to AA-PDF. In addition, the higher release of IL-1 beta and IL-8 by PMO isolated from G-PDF suggests a stronger intra-abdominal activation of PMO, with G-PDF acting as a chemical inflammatory agent. Whether the lower opsonic activity of the AA-PDF is more important for biocompatibility than the other parameters is not clear. Therefore, it is concluded that, although macrophage function is better preserved, it is not proven that the 1.1% AA-PDF studied has an improved biocompatibility compared to 2.27% G-PDF.

Carvedilol Protects against Glomerulosclerosis in Rat Remnant Kidney without General Changes in Antioxidant Enzyme Status

Nephron loss leads to increased production of reactive oxygen intermediates. We measured the effect of carvedilol, a beta-blocking drug with radical scavenging properties, on renal function, glomerulosclerosis, antioxidant enzyme status and in vivo hydrogen peroxide (H2O2) production in rats with chronic renal failure caused by 5/6 nephrectomy (remnant kidney) and compared results to data obtained with propranolol, a beta-blocking drug without scavenging characteristics. Carvedilol and propranolol were administered during 11 weeks following reduction of nephron number. Kidneys were examined using enzymatic and histological techniques. Both carvedilol and propranolol decreased systolic blood pressure. Compared to propranolol, carvedilol offered some additional beneficial effects on renal function, particularly with regard to glomerulosclerosis. Lipid peroxidation, evaluated by malonaldehyde and 4-hydroxynonenal concentration in cortex homogenates, was decreased in carvedilol-treated rats only. Superior beneficial effect of carvedilol treatment is not linked to a significant up-regulation of the activities of the remnant kidney antioxidant enzymes (catalase, glutathione peroxidase and superoxide dismutase) or to a decreased in vivo H2O2 production.

Recurrent Hemolytic Uremic Syndrome and Metastatic Malignancy

A 64-year-old patient with a prostatic adenocarcinoma presented two well-documented episodes of hemolytic-uremic syndrome (HUS) occurring 8 months apart and resolving without renal sequelae. The temporal relationship between these episodes and the natural progression of the underlying disease as well as the absence of chemotherapy favor the hypothesis of cancer-associated HUS. The clinical, laboratory and pathological findings of this patient and 3 additional patients reported in the literature are discussed. These cases suggest that malignancy should be suspected in adults developing the HUS and that this form of HUS need not have a poor prognosis despite progressive cancer.

Diabetes delaying the diagnosis of RPGN.

The present case describes the unusual association of a crescentic glomerulonephritis (GN), diabetes mellitus and a monoclonal gammopathy. After an unexplained deterioration of renal function, a kidney biopsy was performed. The finding of crescentic glomerulonephritis was unexpected. This case illustrates the usefulness of kidney biopsy in diabetes to exclude concomittant disease.

Renal failure in sarcoidosis. Case report of granulomatous interstitial nephritis and review of the literature.

We present the case of a 74-year-old male patient with granulomatous nephritis due to sarcoidosis. We review the different possibilities of renal involvement in sarcoidosis and treatment modalities are discussed.