Clinical and laboratory factors contributing to uninterpretable beryllium lymphocyte proliferation tests (BeLPT).

Abstract

The beryllium lymphocyte proliferation test (BeLPT), has become the principal clinical test for detecting beryllium sensitization and chronic beryllium disease. Uninterpretable BeLPT results can occur in a small but significant proportion of tests from poor lymphocyte growth (PG) or over proliferation of lymphocytes (OP). The clinical and laboratory causes of uninterpretable results are not known. BeLPT data from the US Department of Energy-supported Former Worker Screening Program were analyzed for a 10-year period. Drivers of uninterpretable BeLPTs were investigated using multivariable models and classification techniques. Three participant attributes were significantly associated with PG, while OP showed no significant associations. Serum lot for the lymphocyte growth medium accounted for 21% of the variation in PG and 16% in OP. Serum lots influence the likelihood of having uninterpretable BeLPT. To better understand uninterpretable results and possibly reduce their occurrence, additional laboratory-related factors should be addressed.