Prospective registry of adult patients receiving therapeutic plasma exchange with a presumptive diagnosis of thrombotic microangiopathy (TMA): the Turkish hematology research and education group (ThREG)-TMA02 study

Thrombotic microanjiopathy (TMA) is a pathological diagnosis characterized by abnormalities of small vessels leading to microvascular thrombosis of arterioles and capillaries. The current prospective, non-interventional, multicenter study aimed to define the distribution of different TMA forms in adult Turkish patients who were referred for therapeutic plasma exchange (TPE) for presumptive diagnosis of TMA. Patients with serum ADAMTS13 activity <5% were diagnosed as having acquired thrombotic thrombocytopenic purpura (aTTP). Patients presenting with ADAMTS13 activity 6–10 % / normal renal function and patients with ADAMTS13 activity >10 %, normal renal function and no secondary TMA were treated as unclassified TMA. The study included a total of 80 patients (women: 50; man: 30) with a median age of 48 (20?74). Detailed evaluation at 1 month after hospital admission revealed aTTP, secondary TMA, infection/complement-associated hemolytic uremic syndrome and unclassified TMA in 29 (36.2 %), 22 (27.5 %), 23 (28.8 %) and 6 (7.5 %) patients respectively. As subclassification of various TMAs will dictate specific therapy, proper diagnosis in a timely manner is of utmost clinical significance.     

Pharmacokinetics of piperacillin and tazobactam in critically ill patients with renal failure, treated with continuous veno-venous hemofiltration (CVVH)

Objective: Kinetics of piperacillin (pip), in combination with the beta-lactamase inhibitor tazobactam (taz) have been studied in volunteers and patients in relatively stable conditions. The fixed drug preparation appeared to have ideal pharmacokinetic properties if renal function was normal or slightly impaired, but no data are available for critically ill patients in anuric renal failure. This study should provide such data. Patients, design: We studied the pharmacokinetics in nine patients with multiple organ failure, including anuric renal failure, treated with continuous veno-venous hemofiltration (CVVH). Patients received a standard schedule of 4 g pip and 0.5 g taz administered over 0.5 h intravenously, 8 hourly. During 2 consecutive days, the serum levels of both compounds were determined, and total clearance (CI_T) was calculated from serum concentrations. Results: All nine patients completed day 1, and 8 completed day 2 of the protocol. On day 1, single-dose kinetics showed considerable spread, but pip/taz serum levels followed the pattern as expected, with a pip / taz concentration ratio of 20 : 1. On day 2, however, taz serum concentrations showed a relative increase as compared to pip, resulting in a change in the serum pip/taz concentration ratio to 10 : 1 on day 2. The CI_T of pip was 2.52 ± 1.38 l/h (t ¹/₂ : 5.9 ± 2.9 h), and CI_T of taz 4.44 ± 2.28 l/h (t ¹/₂ : 8.1 ± 3.7 h). The CI_T and t ¹/₂ of pip and taz correlated highly significantly with clearance by CVVH. Despite a higher CI_T, taz has a longer half-life, because of a higher volume of distribution. Conclusion: In CVVH dependent patients, pip/taz fixed drug preparations can be used initially, but the pip dosage should be increased relative to that of taz (or interval-adjusted) to prevent cumulation of taz, as compared to the active antimicrobial agent pip. Received: 19 February 1997 Accepted: 20 May 1997     

The anti-emetic efficacy and tolerability of tropisetron in patients conditioned with high-dose chemotherapy (with and without total body irradiation) prior to bone marrow transplantation

Nausea and vomiting are among the most distressing side-effects of chemoradiotherapy. Conditioning protocols for patients undergoing bone marrow transplantation consist of highly emetogenic high-dose chemotherapy with or without total body irradiation. Marked improvement in controlling emesis and nausea was achieved by the introduction of a new class of antiemetic drugs, the 5HT₃ serotonin-receptor antagonists. Tropisetron is a highly potent, selective antagonist of 5HT₃ receptors. Previous studies have used a single 5-mg dose i.v. of tropisetron to control nausea and vomiting in cancer patients. The present study was undertaken to evaluate the efficacy and safety of a single daily dose of tropisetron in controlling emesis in patients receiving high-dose chemotherapy (with or without total body irradiation) prior to bone marrow transplantation. The anti-emetic efficacy was investigated in a non-homogeneous cohort in a prospective and open study. Of 11 patients evaluated, 9 (81%) showed complete or major control, 1 (9%) minor control and 1 (9%) failed to respond. The most common adverse events reported during the study included diarrhea (46%) and headache (18%), no patients being withdrawn because of side-effects. Our data suggest that a single 5-mg i.v. dose of tropisetron is safe and effective in preventing chemotherapy-induced emesis in patients receiving bone marrow transplantation conditioning. A larger randomized study is warranted to confirm our preliminary results.     

Induction of mucosal healing by intensive granulocyte/monocyte adsorptive apheresis (GMA) without use of corticosteroids in patients with ulcerative colitis: long-term remission maintenance after induction by GMA and efficacy of GMA re-treatment upon relapse

This study examined the long-term maintenance rate after inducing remission by intensive granulocyte/monocyte adsorptive apheresis (GMA) without use of corticosteroids (CS) and GMA re-treatment efficacy in the same patients upon relapse with ulcerative colitis. Patients who achieved clinical remission and mucosal healing (MH) by first-time intensive GMA (first GMA) without CS were enrolled. The cumulative non-relapse survival rate up to week 156 was calculated. Patients with relapse during the maintenance period underwent second-time intensive GMA (second GMA) without CS. Clinical remission and MH rates following second GMA were compared to those following first GMA in the same patients. Of the 84 patients enrolled, 78 were followed until week 156 and 34 demonstrated relapse. The cumulative non-relapse survival rate by week 156 was 56.4%. Clinical remission and MH rates after second GMA did not differ from those after first GMA in the same patients (week 6: clinical remission, 100% vs 88.4%, p = 0.134; MH, 100% vs 84.8%, p = 0.074). In conclusion, MH induction by intensive GMA without use of CS in ulcerative colitis patients contributes to subsequent long-term clinical remission maintenance. GMA re-treatment efficacy was comparable to that of first GMA in the same patients who had relapse.     

Evaluation of hiv p24 antigen,beta2-microglobulin,neopterin, soluble cd4, soluble cd8, and soluble interleukin-2 receptor levels in patients with aids or aids-related complex treated with 2′,3′-dideoxyinosine (ddl)

Circulating HIV P24 antigen, beta2-microglobulin, neopterin, soluble CD4, soluble CD8, and soluble interleukin-2 receptor were measured in 13 zidovudine-intolerant patients (8 with ARC and 5 with AIDS) treated with dideoxyinosine (ddI). Measurements were made at baseline and at several intervals during therapy. Mean levels of HIV P24 antigen decreased early and significantly (^P<0.01) after 2 weeks of ddI administration and remained low at weeks 8 and 12. In addition, mean SCD8 levels decreased late and significantly (^P<0.02) after 16 weeks of ddI treatment and remained low at 24 weeks. In contrast, ddI administration had no substantial effect on mean levels of beta2-microglobulin, neopterin, soluble CD4, and soluble interleukin-2 receptor. ddI administration appears to have been associated with early reduction of HIV P24 antigen levels and later reduction of SCD8 mean levels in these patients.