Plasma infusion for hemolytic-uremic syndrome in children: results of a multicenter controlled trial. Antiplatelet agents in thrombotic thrombocytopenic purpura (TTP). Results of a randomized multicenter trial by the Italian Cooperative Group for TTP. Design of the prospective randomized study for the treatment of patients with thrombotic microangiopathy. PRODROMI Study Group. Heparin therapy in the hemolytic-uremic syndrome. Does cryosupernatant plasma improve outcome in thrombotic thrombocytopenic purpura? No answer yet. Treatment of the childhood haemolytic uraemic syndrome with plasma. A multicentre randomized controlled trial. The French Society of Paediatric Nephrology. Heparin plus dipyridamole in childhood hemolytic-uremic syndrome: a prospective, randomized study. Effect of an oral Shiga toxin-binding agent on diarrhea-associated hemolytic uremic syndrome in children: a randomized controlled trial. Comparison of plasma exchange with plasma infusion in the treatment of thrombotic thrombocytopenic purpura. Canadian Apheresis Study Group. Steroids in the hemolytic uremic syndrome. Cryoprecipitate poor plasma does not improve early response in primary adult thrombotic thrombocytopenic purpura (TTP). [Treatment of childhood hemolytic-uremic syndrome with urokinase. Cooperative controlled trial].
The results of a controlled trial to ascertain the usefulness of plasma infusion for the treatment of hemolytic-uremic syndrome (HUS) are reported. Criteria for admission were (1) observation within 8 days from first symptoms, (2) dialysis treatment required, and (3) no special treatments and no more than 25 ml blood/kg previously received. Children were subdivided according to age (less than or more than 3 years) and then randomly assigned to treatment with plasma or symptomatic therapy. Thirty-two children ranging in age from 4 months to 6 years entered this study; 17 received plasma (P+ group) and 15 only symptomatic therapy (P- group). The mean follow-up period was 16 months in both groups. Surgical renal biopsy was performed 29 to 49 days after onset in 11 P+ and 11 P- children, and 33 histologic findings were semiquantitatively evaluated. No death occurred in either group. No differences were found in blood pressure, proteinuria, or hematuria at the end of the follow-up period; in no case were severe arteriolar lesions found. There were no significant differences for the scores of the individual histologic measurements; on electron microscopy, no vascular changes were observed in seven children of the P+ group, whereas in five of seven of the P- group, thickening of the lamina rara interna and arteriolar damage were present. The ability of plasma to stimulate prostacyclin (PGI2) production, measured as its stable derivative 6-keto-PGF1 alpha, was within the normal range for all patients. In our patients with predominant glomerular involvement who were treated in a very early phase of HUS, infusions of plasma did not significantly influence the short- and medium-term clinical outcome and were not effective in severe HUS when given later in the course of the disease. A longer follow-up is needed to ascertain whether the presence of endothelial damage, demonstrated by electron microscopy in children who were not given plasma, is of clinical relevance. Antiplatelet agents are often included in plasma exchange-based regimens for thrombotic thrombocytopenic purpura (TTP) patients; however, the opportuneness of their use in TTP is still controversial. The italian Cooperative Group for TTP carried out a randomized trial to investigate their actual effectiveness, both in acute TTP and as maintenance treatment.
                Seventy-two TTP patients were randomized to receive plasma exchange and steroids with (group B) or without (group A) aspirin and dipyridamole. Treatment efficacy was evaluated after 15 days and salvage treatments were also considered for non-responders. Upon disease remission, the patients already treated with antiplatelet agents received ticlopidine for one year.
                Regarding the treatment of acute phase TTP, similar overall response rates were observed in the two groups (91.4% in group B vs. 75.6% in group A), but lower mortality rates were observed at 15 days in the patients treated with antiplatelet agents; as a matter of fact, 5 patients from arm A died in the first 15 days (13.5%) versus only one in arm B (2.8%). These figures, while not statistically significant, seem to suggest that antiplatelet agents might be useful in preventing deaths in acute TTP; moreover, bleeding did not worsen in antiplatelet agent-treated patients. As for the role of maintenance treatment, our results support the efficacy and safety of one-year ticlopidine therapy since the current relapse rate is significantly higher in non-treated patients; as a matter of fact, 6 patients (21.4%) in the non-ticlopidine group and only 2 (6.25%) in the ticlopidine group relapsed (P = .0182 in favor of maintenance treatment).
                Our results suggest the usefulness of antiplatelet agents in the treatment of acute phase TTP patients. Moreover, one-year ticlopidine maintenance therapy appears to be beneficial in preventing TTP relapses; however, only the completion of an adequate follow-up for all patients will definitively confirm this observation. In thrombotic microangiopathies hemolytic uremic syndrome and thrombocytopenic purpura, plasma exchange (PE) therapy using fresh frozen plasma is standard. In almost 20% of the patients, however, this approach is ineffective. This prospective, randomized study for the treatment of patients with thrombotic microangiopathies (PRODROMI) compares PE with fresh frozen plasma (A) and cryosupernatant (B). The participating centers were the University Clinics of Freiburg, Hamburg, Düsseldorf, Essen, Göttingen, Mannheim, Ulm, Jena, Tübingen, Würzburg, Kreiskrankenhaus Offenburg, Städt Klinikum Karlsruhe, and Horst-Schmidt Kliniken in Wiesbaden, Germany. Patients (18 to 80 years) were diagnosed by the individual centers based on clinical and laboratory findings (thrombocyte/fragmentocyte count, hemoglobin, serum creatinine, haptoglobin and lactate dehydrogenase levels; negative Coombs-test is obligatory). HIV infection, bone marrow, or solid organ transplantation were exclusion criteria. After written consent, patients were randomized in the A or B group. All patients received 1.5 mg/kg methylprednisolone as a basic therapy. The first PE always was performed with fresh frozen plasma (50 ml/kg). A minimum of 5 and a maximum of 10 PEs were required. Thrombocyte count above 150,000/microl was considered to be a successful therapy. Treatment failure was defined as not responding to 10 PE with a thrombocyte count above 150,000/microl or a fall below this value within 30 days after stopping PE. Patients with clinical and laboratory signs of thrombotic microangiopathy occurring later than 30 days after having stopped PE were considered to have a relapse. Primary endpoints were survival, intensity of required PE sessions (duration, volume, and number), and relapse rate. Follow-up of clinical outcome was 2 years; von Willebrand Factor (vWF), vWF-cleaving-protease activity, and Factor H were determined. nan A randomized prospective trial compared cryosupernatant plasma (CSP) to fresh frozen plasma (FFP) for treatment of thrombotic thrombocytopenic purpura (TTP). A total of 236 patients were required: 28 patients were treated with CSP and 24 with FFP within 30 months. There were no differences in survival at 1 month. By day 9, 17 of 26 patients with CSP and 18 of 24 with FFP had a platelet count >100 x 10(9)/l. At entry, von Willebrand factor (VWF) multimers were normal in all patients (range 1.1-3.95 IU/ml). ADAMTS-13 levels showed large variations ranging from 10% to 100% activity. At entry, no individual had <5% VWF cleaving protease. By day 9 (end of cycle), 89% (FFP) and 67% (CSP) had levels >50% of the controls. At 6 months some patients showed inhibitors to the enzyme in spite of adequate or normal platelet counts. The data from this study do not show an apparent advantage to the use of CSP in TTP. A large number of patients will be required to determine appropriate replacement therapy. We were not able to find a statistically significant relationship between the low level of protease activity at presentation of TTP and response. Seventy-nine children with haemolytic uraemic syndrome (mean age 28 months) were randomly assigned either to a group receiving plasma infusions (plasma group, n = 39) or to a group treated conservatively (control group, n = 40). The duration of haemolysis, thrombocytopenia and anuria was similar in the two groups. Serum creatinine levels were similar in the two groups at the 1-month follow-up but were higher in the control group at 3 months (plasma group 49 +/- 14, control group 66 +/- 28 mumol/l; P less than 0.02) and at 6 months (plasma group 48 +/- 13, control group 63 +/- 21 mumol/l; P less than 0.005). The prevalence of proteinuria was also higher in the control group at the 6-month follow-up (plasma group 17%, control group 46%; P less than 0.02). However, differences were no longer significant after 1 year. Renal tissue was examined in 54 cases (plasma group, n = 27; control group, n = 27). Diffuse cortical necrosis was present in 7 cases in the control group but was absent in the plasma group (P less than 0.02). Taking into consideration the higher serum creatinine levels, the higher prevalence of proteinuria during the first 6 months of follow-up in the control group and the presence of diffuse cortical necrosis in this group compared with the plasma group, we conclude that plasma infusions should be regarded as beneficial. Further study is needed to determine which plasma fraction is involved. From 1976 to 1985, a total of 58 infants and children with the hemolytic-uremic syndrome were randomly assigned to treatment either with heparin and dipyridamole or with supportive management only. In the treatment group, two patients died in the early weeks of the disease. Analysis of clinical and laboratory data showed no significant difference between either group of patients as to the evolution of their illness except for a significantly higher incidence of anuria and a significantly faster recovery from hypertension in the treated group. Renal biopsy studies showed no differences between the two groups in terms of incidence and severity of the histologic lesions. The long-term data on blood pressure and creatinine clearance values in the survivors were similar in both groups. This study indicates that treatment with heparin and dipyridamole has no benefit over symptomatic therapy alone in the typical form of childhood hemolytic-uremic syndrome. Diarrhea-associated hemolytic uremic syndrome (HUS) is the most common cause of acute renal failure in children. Most cases are caused by an intestinal infection with Shiga toxin-producing strains of Escherichia coli.
                To determine if administration of an oral agent that binds Shiga toxin could diminish the severity of diarrhea-associated HUS in pediatric patients.
                Multicenter, randomized, double-blind, placebo-controlled clinical trial of 145 children (96 experimental and 49 placebo) aged 6 months to 18 years with diarrhea-associated HUS conducted between July 27, 1997, and April 14, 2001, at 26 tertiary care pediatric nephrology centers in the United States and Canada. Trial included 2 phases, the hospital course for treatment of the acute illness and a 60-day outpatient follow-up period after discharge from the hospital.
                Patients were assigned to receive the binding agent, 500 mg/kg daily, or cornmeal placebo orally for 7 days in a 2:1 randomization scheme.
                Combined frequency of death or serious extrarenal events and need for dialysis in the experimental vs placebo group.
                A total of 62 patients (43%) were male and 123 (85%) were white. The median age of the patients was 4.2 years. Most patients (59%) were transferred from other hospitals to participating sites. The severity of disease at the time of randomization was comparable in the 2 groups. The prevalence of death or serious extrarenal events was 18% and 20% in the experimental and placebo groups, respectively (P =.82). Dialysis was required in 42% of experimental and 39% of placebo groups (P =.86).
                Oral therapy with a Shiga toxin-binding agent failed to diminish the severity of disease in pediatric patients with diarrhea-associated HUS. Thrombotic thrombocytopenic purpura is an uncommon disease with a high mortality rate even with current treatment. The cause of the syndrome and its optimal treatment are unknown. Although both plasma exchange and plasma infusion have been useful treatments, it is not clear which is superior. In this report we describe a prospective randomized trial comparing plasma exchange with plasma infusion for the treatment of thrombotic thrombocytopenic purpura.
                One hundred two patients with thrombotic thrombocytopenic purpura were randomly assigned to receive either plasma exchange or plasma infusion with fresh-frozen plasma on seven of the first nine days after entry into the trial. The total volume of plasma received by patients undergoing plasma exchange was three times that received by patients undergoing plasma infusion. All the patients also received aspirin and dipyridamole. The outcomes in the two groups were compared at the end of the first treatment cycle (day 9) and after six months.
                At the end of the first treatment cycle patients receiving plasma exchange had a higher rate of response as defined by an increase in the platelet count (24 of 51 patients) than those who received plasma infusion (13 of 51, P = 0.025). Of the 51 patients treated with plasma exchange, 2 died, whereas 8 of the 51 patients who received plasma infusion died (P = 0.035). After six months the outcome in the plasma-exchange group was still superior, with a response observed in 40 of 51 patients, whereas 25 of 51 patients in the plasma-infusion group responded (P = 0.002). Eleven patients in the plasma-exchange group died, as did 19 patients in the plasma-infusion group (P = 0.036). The overall mortality was 29 percent.
                Plasma exchange is more effective than plasma infusion in the treatment of thrombotic thrombocytopenic purpura. To determine whether steroids could be of clinical benefit in the treatment of the hemolytic uremic syndrome (HUS), we conducted a randomized, double-blinded, placebo-controlled trial of methylprednisone (5 mg/kg per day in four oral doses over 7 days), in children with HUS during the acute phase. Ninety-two patients with typical HUS (47 receiving placebo and 45 receiving steroids) were investigated for neurological, hematological, and nephrological variables. There were no differences between groups in the number of convulsive episodes or transfusion requirements during the hospital stay. Serum creatinine levels were slightly increased on day 10 in the placebo group compared with the steroid group (P = 0.06) and declined significantly between days 1 and 10 only in the steroid group (P = 0.001). In the 51 patients with anuria (24 placebo, 27 steroids), median serum creatinine levels were reduced in the steroid group compared with the placebo group on the 10th day (P = 0.01). Differences in median days of oliguria [11.5 versus 8 (P = 0.28)], anuria [5 versus 7 (P = 0.20)], and dialysis [12 versus 10 (P = 0.26)] for the placebo and the steroid group respectively were not significant. Our data suggest that oral steroids are not able to modify hematological, neurological, or nephrological clinical parameters during the acute phase of childhood HUS, even though they do seem to be associated with a more rapid decline in serum creatinine levels. Thrombotic thrombocytopenic purpura (TTP) is a potentially fatal disease that is treated with plasma exchange and typically with replacement with fresh frozen plasma (FFP). This approach results in an approximate 50% response rate following 1 week of therapy and 80% survival. Cryoprecipitate poor plasma (CPP) is plasma from which the cryoprecipitate fraction is removed. CPP has been reported to be successful as salvage therapy in refractory TTP and has been suggested to be superior to FFP in retrospective studies. The present report compares initial therapy of TTP with exchange using replacement with either FFP or CPP in a multi-institutional prospective randomized study performed by the North American TTP Group (NATG Group) from 1993 to 1995. Initial therapy also included corticosteroids. Antiplatelet drugs or vinca alkaloids were not employed. A severity score index, response score, and individual clinical parameters (platelet count, LDH x upper limit of normal, hemoglobin level, and creatinine) were compared at their nadir or peak values, baseline, and days +6 and +13 of therapy. Thirteen patients were randomized to FFP exchange and 14 to CPP exchange. Results were equivalent for all parameters. Survival was equal with three deaths in each group. These data indicate that the efficacy of FFP and CPP are the same in the initial treatment of TTP in adults. The results of a controlled therapeutic trial comparing 2 groups of patients presenting with hemolytic-uremic syndrome (HUS) are reported. Group A (15 children) was given urokinase (UK) and heparin; group B (18 children) received no treatment. Ages of patients, the delay before admission, the severity of anemia, thrombocytopenia and initial renal failure were similar in both groups. UK was responsible for bleedings in 12 children, minimal in 8, severe in 4. No child died in group A, 3 children died in group B (n.s.). Durations of hemolysis, thrombocytopenia and anuria were similar in both groups. Long-term evolutions of renal function and arterial pressure were comparable in both groups. Needle kidney biopsy (26 cases) showed cortical necrosis in 3 children of group A and in 2 of group B, and glomerular thrombotic microangiopathy in 10 children of group A and in 11 of group B. The average ratio of injured glomeruli was 40 (19 to 80) in group A, and 38 (21 to 75) in group B. Two children in group A and 3 children in group B presented with 50 to 80% of glomerular lesions. This trial suggests that UK is of no significant value in the treatment of HUS.
PE with FFP is still the most effective treatment available for TTP. For patients with HUS, supportive therapy including dialysis is still the most effective treatment. All studies in HUS have been conducted in the diarrhoeal form of the disease. There were no RCTs evaluating the effectiveness of any interventions on patients with atypical HUS who have a more chronic and relapsing course.