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Biomedical subjects

G Remuzzi

Publications and source records attributed to G Remuzzi.

At least 487 records · Page 27Linked to original sources

Bleeding in renal failure: a possible role of vascular prostacyclin (PGI2).

Specimens of venous tissues from a group of 25 patients with chronic uremia and 7 patients with acute renal failure generated significantly higher PGI2-like (platelet aggregation inhibiting) activity than venous tissues from 30 normal subjects. After repeated washings, when this activity could barely be detected in the controls, pronounced inhibitory activity was still evident in samples containing venous tissues from uremic patients. Both prolonged bleeding times and increased PGI2-like activity returned to normal in 4 acute uremic patients on restoration of their renal function. These findings may be relevant to the pathogenesis of bleeding in renal failure.

Acute Kidney Injury↗

Treatment of the hemolytic uremic syndrome with plasma.

Two patients with the hemolytic uremic syndrome were treated with plasma exchange an infusion: in both cases, the reduced platelet count reverted to normal values and the microangiopathic anemia ceased within a few days. Systemic blood pressure and requirement for antihypertensive drug therapy were also markedly reduced following treatment with plasma. Venousprostacyclin (antiplatelet aggregating) activity was undetectable in both patients before but was restored after treatment with plasma. The plasma samples collected before, but not those collected at various intervals after replacement therapy, had decreased capacity to stimulate prostacyclin activity in rat aortic rings. It is suggested that in patients with the hemolytic uremic syndrome or with other clinical conditions which can be included under this rubric (such as thrombotic thrombocytopenic purpura) a plasma factor is lacking which stimulates prostacyclin activity. Plasma would supply such a missing factor, thus representing a rational treatment for some of the life-threatening manifestations (thrombocytopenia, hemolytic anemia, hypertension) of this severe syndrome.

Antihypertensive Agents↗

Haemolytic-uraemic syndrome: deficiency of plasma factor(s) regulating prostacyclin activity?

It is suggested that patients with the haemolytic-uraemic syndrome and related disorders (such as thrombotic thrombocytopenic purpura) lack a plasma factor which stimulates prostacyclin (P.G.I2) activity. Normal plasma would supply the missing factor and is a rational treatment for some life-threatening symptoms (thrombocytopenia, haemolytic anaemia, hypertension) of this syndrome.

Anemia, Hemolytic↗

Factor VIII--related protein on vascular intima of patients with chronic renal failure and prolonged bleeding times.

To determine whether the prolonged bleeding time so common to chronic renal failure (CRF) was due to defective factor VIII-related activities, as in von Willebrand's disease, vascular-factor VIII-related protein was measured in patients with CRF. Factor VIII-related protein was detected by immunofluorescence on the vascular intima of all 13 patients with CRF and greatly prolonged bleeding times. This protein was also present on the vascular intima of a patient with CRF and moderate von Willebrand's disease. These findings support a previous suggestion that the disturbed haemostasis in patients with CRF is not linked to defective factor VIII-related activities.

Adult↗

Bleeding in renal failure: altered platelet function in chronic uraemia only partially corrected by haemodialysis.

Bleeding time, blood loss and platelet retention by glass beads, measured by standardized techniques, were significantly altered in a group of 30 non-thrombocytopenic patients with chronic renal failure undergoing maintenance haemodialysis. Bleeding time or blood loss did not correlate with platelet retention either before or after haemodialysis. No correlation could be found between the above tests and a number of biochemical parameters characterizing the uraemic condition. Haemodialysis only partially corrected the abnormal bleeding time, blood loss and platelet retention. These tests were still significantly different after haemodialysis from those of 30 normal subjects. It is suggested that some non-dialyzable material could play an important role in the aetiology of uraemic bleeding.

Adult↗

Vascular factors in the pathogenesis of uraemic bleeding.

To determine the possible role of vascular factors in the bleeding tendency of uraemic patients, three major factors of the haemostatic system normally present in vascular tissues were studied. Factor VIII-related protein (F VIII) was detected on the vascular intima of 13 patients and 10 normal subjects. Comparable values of plasminogen activator (PA) were found in tissue slices from 7 patients and 7 controls. In contrast, prostacyclin like (PGI2) activity, measured as platelet aggregation inhibitory potency, was significantly higher in specimens from 15 patients with either acute or chronic uraemia than in 10 controls. The latter abnormality, leading to impaired platelet-vessel wall interaction, might contribute to the disturbed haemostasis of uraemic patients.

Adult↗

Prostacyclin-like activity and bleeding in renal failure.

Specimens of venous tissue from three normal subjects and three patients with renal failure and very prolonged bleeding-times showed prostacyclin-like activity (inhibition of platelet aggregation) during incubation at room temperature. The specimens from all three uraemic patients showed more prostacyclin-like activity than those from the controls. After repeated washings, when this activity could hardly be detected in the controls, pronounced inhibitory activity was still evident in samples containing venous tissue from the three uraemic patients. These findings may be relevant to the pathogenesis of bleeding in renal failure.

Acute Kidney Injury↗

Bleeding in renal failure: is von Willebrand factor implicated?

Normal or increased concentrations of factor VIII procoagulant activity (VIIIC), factor VIII-related antigen (VIIIRA), and factor VIII-von Willebrand activity (VIIIVWF) were found in the predialysis plasma of 10 out of 11 patients with chronic renal failure (CRF). All patients had a bleeding time longer than 15 minutes and platelet retention to glass beads lower than 40%. The only patient who had reduced concentrations of all three factor VIII complex components was subsequently shown to have von Willebrand's disease. In four patients with CRF, very low platelet retention, and slightly prolonged bleeding time none of the three factor VIII COMPLEX COMPONENTS WERE SELECTIVely modified in predialysis samples. These findings suggest that the bleeding tendency common in CRF is not necessarily linked to defective plasma factor VIII-related activities.

Adult↗