Evaluation of lymphocyte transformation test results in patients with delayed hypersensitivity reactions following the use of anticonvulsant drugs

Background/Aim: Administration of the anticonvulsant drugs phenobarbital, phenytoin, carbamazepine and lamotrigine can be associated with severe hypersensitivity reactions. The lymphocyte transformation test (LTT) is a method to determine which drug has caused the hypersensitivity reaction. This study was done to evaluate the results of LTT in patients with delayed hypersensitivity reactions following the administration of anticonvulsants. Methods: Twenty-four patients with hypersensitivity reactions, e.g. drug-induced hypersensitivity syndrome/drug rash and eosinophilia with systemic symptoms (DIHS/DRESS), Stevens-Johnson syndrome (SJS) and toxic epidermal necrosis (TEN), following the administration of anticonvulsant drugs, and 24 patients who had used anticonvulsant drugs but did not have hypersensitivity reactions (the control group) were included in this study. Peripheral blood mononuclear cells were isolated. The cells were stimulated with the drugs, phytohemagglutinin as a mitogen and Candida as an antigen (positive controls). Lymphocyte proliferation was measured using the BrdU proliferation assay kit (Roche, Germany). The stimulation index was calculated as the mean ratio of the OD of stimulated cells divided by the OD of unstimulated cells. The results in the case and control groups were compared. Results: Of 24 patients in the test group, 14 (58.3) had positive LTT results and 10 (41.7) had negative results. Among patients in the control group, 1 (4.2) had a positive LTT result and 23 (95.8) had negative results. Among the patients who had received carbamazepine and phenytoin, there was a significant difference between the results of LTT in the case and control groups (p = 0.002 and p = 0.028, respectively). Although patients receiving lamotrigine and phenobarbital had more positive LTT results in the case group than in the control group, these differences were not statistically significant. The sensitivity, specificity, positive predictive value and negative predictive value of LTT were 58.4, 95.8, 93.3 and 69.9, respectively. Conclusions: Considering the significant difference in LTT results between the case and control groups in patients receiving carbamazepine and phenytoin, and not observing such a difference in patients receiving phenobarbital and lamotrigine, LTT results are more valuable for the diagnosis of hypersensitivity reactions following the administration of carbamazepine and phenytoin. The LTT has good specificity but low sensitivity for the diagnosis of drug hypersensitivity reactions. © 2016 S. Karger AG, Basel

ATP-Binding Cassette transporters' gene expression in pediatric patients with acute leukemia; a comprehensive analysis of published reports through PubMed search engine

Multidrug resistance based on ABC transporters' gene expression is one of the most important health challenges through chemotherapy of patients. This resistance can cause relapse or treatment failure. The goal of this conducted study was to evaluate the results of published reports which considered ABC transporters' gene expression in pediatric patients with acute leukemia. PubMed as a free search engine was chosen. The following Mesh terms were used as: "ATP-binding cassette transporters" OR "ABC-transporters*" AND "gene expression*" AND "leukemia" OR "ALL" OR "AML" OR "acute leukemia*". Age was set as an additional filter with the age range of birth to 18 years old. Initial screening was performed according to inclusion and exclusion criteria and the quality of the selected papers was assessed. Papers categorized into three sections as: pediatric patients with ALL (6 papers from 1998-2015); pediatric patients with AML (3 papers from 1992-2011) and pediatric patients with ALL and AML (7 papers from 1992-2014). Totally 1118 patients enrolled in the searched studies (ALL and AML: 488; ALL: 405; AML: 225). The common method for evaluating gene expression of ABC transporters was RT-PCR. More than 50 of the papers showed the influence of ABC transporters' gene expression on prognosis and treatment failures of patients. Despite controversial results, the gathered information in the current report serves as a comprehensive referential resource, which can be beneficial for future planning around this title, especially in developing countries