The Lymphocyte Toxicity Assay
The LTA is a safe in vitro test used to identify patients who are at high risk of developing DHS. The test has been used for decades to test patient susceptibility to DHS. The principle of the test is based on a clinical finding that DHS-susceptible patients have an impaired ability to detoxify toxic reactive metabolites of drugs leading to accumulation of these toxic entities in their bodies, as compared to healthy (non-hypersensitive) individuals. Lymphocytes isolated from blood samples from DHS patients exhibit higher degree of cell death upon incubation with the suspected drug (or its metabolite). The test has been proven to have a clinical sensitivity between 80% and 90% in identifying patients at risk. These tests can be used to aid diagnosis of suspected DHS to a wide variety of commonly used rugs including Sulfonamides, aromatic anticonvulsants, antibiotics and NSAIDs.