ACOX1 and X-linked adrenoleukodystrophy: All infants that screen positive are referred to Gifu University, and ALD can be diagnosed within 5 days, and PD with increased VLCFA other than ALD, such as PBD, Acyl-CoA oxidase 1 deficiency, and D-bifunctional protein deficiency can be diagnosed promptly using our diagnostic system (Figure 1).