Neonatal urine screening for metabolic disease with auxotrophic strains of Bacillus subtilis

A simplified method for neonatal urine screening for metabolic diseases is described. This procedure involves the use of two bacterial inhibition assays which can detect uracil, lysine, and homocystine, in combination with two other assays utilizing spores of amino acid auxotrophic mutants of Bacillus subtilis which can detect several amino acids and purines. These four tests have the capability to detect several treatable inherited metabolic diseases, including three disorders of the urea cycle, using a urine specimen on filter paper. This method results in savings of cost and time over chromatographic screening procedures, since only four agar trays (56 specimens per tray) are used, which can be processed with one cycle through a semi-automated punch index machine.