Clinical usefulness of lymphocyte transformation in patients with coccidioidomycosis

The development of an appropriate host defense in coccidioidomycosis is predicated on the presence of a positive delayed skin test reaction to coccidioidin. In severe and/or disseminated disease, coccidioidin reactions are routinely negative. By employing serial in vitro spherulin-induced lymphocyte blast transformation (LT) studies in a group of eight severely-ill coccidioidomycosis patients, prognostic clinical data were provided which could not have been obtained from their skin test status alone. Four of the eight demonstrated positive LT responses early in the course of their disease, quickly converted their skin tests to positive, and were cured of their disease. Two patients had negative LT responses until their skin test converted after several months of therapy. The final two have continued to demonstrate negative LT values despite several years of therapy and have experienced exacerbations of their disease when treatment was discontinued. The use of LT data in such patients can be very helpful in guiding therapeutic decisions in this difficult clinical problem.