Lymphocytes do not contain leukocyte esterase and would not produce a positive leukocyte esterase reaction on the reagent strip.
Positive results should be confirmed by performing microscopic examination of the sediment. Note that white blood cells would not be seen in the sediment if they have lysed; however, the leukocyte esterase reaction on the reagent strip would still be positive because esterase is still present in the urine.
