FAH and Tyrosinemia type 1: Phenylalanine and tyrosine restricted formula without lactose should be a better option rather than overall protein restriction; (6) Genetic testing may take weeks or months before diagnosis, but polymerase chain reaction (PCR) screening for population specific hot-spot mutations in SLC25A13 and FAH (fumarylacetoacetase) gene, serum pancreatic secretory trypsin inhibitor (PSTI), and blood/urine succinylacetone will be available within days, and should be considered for differential diagnosis of NICCD from tyrosinemia type 1.