Frequency and specificity of red blood cell alloimmunization in chilean transfused patients.

BACKGROUND: Alloimmunization is an adverse effect of blood transfusions. In Chile, alloimmunization frequency is not established, and for this reason the aim of this study was to investigate the prevalence and specificity of red blood cell (RBC) alloantibodies in Chilean transfused subjects. METHODS: Records from 4,716 multi-transfused patients were analyzed. In these patients, antibody screening was carried out prior to cross-matching with a commercially available two-cell panel by the microcolum gel test, and samples with a positive screen were analyzed for the specificity of the alloantibody with a 16-cell identification panel. RESULTS: The incidence of RBC alloimmunization in transfused patients was 1.02% (48/4,716) with a higher prevalence in women (40/48). We detected 52 antibodies, the most frequent specificities identified were anti-E (30.8%), anti-K (26.9%), anti-D (7.7%), and anti-Fy(a) (5.8%). The highest incidence of alloantibodies was observed in cancer and gastroenterology patients. CONCLUSION: The data demonstrated a low alloimmunization frequency in Chilean transfused patients, principally associated with antibodies anti-E, anti-K, anti-D, and anti-Fy(a).

Fecal calprotectin and alpha-1 antitrypsin predict severity and response to corticosteroids in gastrointestinal graft-versus-host disease.

Diagnosis of gastrointestinal GVHD (GI-GVHD) is based on clinical symptoms and histologic findings. No biomarkers predicting responses to treatment are routinely available even though 30% to 50% of patients will not respond to corticosteroids. In this study, we aimed to evaluate fecal calprotectin, α-1-antitrypsin (α(1)-AT), and elastase at the time of first symptoms as diagnostic and prognostic tools for GI-GVHD in 72 consecutive patients, of whom 51 developed GI-GVHD. The prognostic value of markers was evaluated by their association with complete response (CR) and steroid-resistant (SR) GVHD. Calprotectin and α(1)-AT concentrations increased with GI-GVHD initial stages but patients with initial stage 1 GI-GVHD had similar marker levels to patients without GI-GVHD, so sensitivity to diagnose GI-GVHD was weak. In contrast, calprotectin and α(1)-AT were predictors for SR-GVHD and CR. Multiple regression modeling identified calprotectin and α(1)-AT concentration as independently predicting SR-GVHD together with initial stage > 2 GI-GVHD. Our results showed that fecal calprotectin and α(1)-AT levels at the time of diagnosis are predictive for responses to treatment but are not diagnostic markers for initial stage 1 to 3 GI-GVHD.

Rituximab and escalated chemotherapy in elderly patients with aggressive diffuse large-cell lymphoma: a controlled clinical trial.

The treatment of elderly patients with aggressive malignant lymphoma has not been defined. The addition of rituximab to conventional chemotherapy has been reported to improve the outcome, but most patients have good prognostic factors (performance status < 2, no severe associated diseases, low or low-intermediate clinical risk). Thus, we developed a combined regimen, including escalated doses of anthracycline and rituximab. The endpoint was to improve event-free survival (EFS) and overall survival. Two hundred and four (204) patients were randomly assigned to receive an escalated chemotherapy regimen (CEOP) with escalated dose of epirubicin, compared to the same regimen and addition of rituximab. All patients had poor prognostic factors: high- or high-intermediate clinical risk, poor performance status, bulky disease, and more than 2 with extranodal involvement. In an intent-to-treat analysis, all patients were evaluable for efficacy and toxicity. The complete response rates were similar in both arms: 74% in chemotherapy and 78% in the rituximab + chemotherapy program. EFS and overall survival were similar: 77% and 84%, respectively, in combined chemotherapy and 75% and 81% in the rituximab-chemotherapy regimen. Toxicity was mild and well tolerated. In elderly patients with diffuse large-cell lymphoma and poor prognostic factors, rituximab did not improve their outcome.

Dose dense (CEOP-14) vs dose dense and rituximab (CEOP-14 +R) in high-risk diffuse large cell lymphoma.

To assess efficacy and toxicity of rituximab and dose chemotherapy in high-risk diffuse large cell lymphoma, we conducted a controlled clinical trial to assess efficacy and toxicity of a dose-dense regimen CEOP- 14 (cyclophosphamide, epirubicin, vincristine, and prednisone every 14 d) compared to CEOP-14 plus rituximab. One hundred and ninety-six patients were randomized to received CEOP-rituximab (cyclophosphamide 1500 mg/m2, epirubicin 120 mg/m2, vincristine, and prednisone at standard dose and rituximab at 375 mg/m2) compared with the same chemotherapy administered every 14 d (CEOP-14). In an intent-to-treat analysis all patients were available for efficacy and toxicity. Complete response in CEOP-14 was observed in 73 cases (74%) and in 75 patients (76%) in the CEOP-R regimen (76%) (p = 0.8). With a median follow-up of 53.4 mo, median has not been reached in time to tumor-progression (TTP) and overall survival (OS). Actuarial curves at 5 yr showed that TTP and OS in patients treated with CEOP-R were 74% and 67%, respectively, that were not statistical different when compared to CEOP-14, 72% and 65%, respectively (p = 0.8). Acute toxicity was mild and well tolerated. The use of a dense-dose regimen is useful and well tolerated in patients with very high risk diffuse large cell lymphoma. The addition of rituximab did not improve outcome in these setting of patients.

Inhibition of mitogen-activated protein kinase activity of human lymphocytes after oral administration of Oltipraz.

Several preclinical studies indicated that Oltipraz appears to be one of the most potent cancer chemopreventive agents. Pharmacological studies in humans provided substantial amounts of information related to doses and schedules. Oltipraz has been reported to induce phase II drug-metabolizing enzymes. However, its chemopreventive activity suggests that it may also interact with cellular processes associated with cancer cell growth and proliferation. During a clinical trial designed to monitor eventual Oltipraz toxicity in high-risk population for development of lung cancer, we performed companion studies related to cell proliferation. Human lymphocytes were chosen as surrogate tissue to assess the in vivo effects of Oltipraz on cell signaling pathways involved in cell proliferation. The results of this study demonstrate that Oltipraz markedly inhibited the activation state of the extracellular signal-regulated kinases of the mitogen-activated protein kinase family of kinases in lymphocytes of subjects treated with two different doses and schedules of Oltipraz. Individual variations were observed that were not related to Oltipraz dosing or schedule of administration. The results from this study indicate that lymphocytes could be used as surrogate tissue for the development of biomarkers for studies of anticarcinogenic agents.