Abstract: The invention relates to a disposable diagnostic card for detecting an analyte in a fluid sample, comprising a base with a support surface for supporting a reagent strip and a sample receiving chamber; and a cover placed tightly on the base with an opening over the chamber of the base for introducing the sample, and a window over part of the reagent strip for observing a reaction thereon. An end of the reagent strip is bent and inserted into the sample receiving chamber, the sample in the chamber being movable by capillary action through the reagent strip from said bent end. The invention also relates to an electronic reading device having a housing for inserting a diagnostic card, optical reading means for reading a change in color on the reagent strip, and display means for visually presenting the results of the reading.