ADSL and adenylosuccinate lyase deficiency: ADSLD can be diagnosed by detecting elevated levels of the substrates of ADSL, SAICAR (also referred to as SZMP), and S-AMP, as well as their dephosphorylated riboside forms, SAICAr and S-Ado, in bodily fluids (Jaeken and Van den Berghe, 1984).