Figure 2
From: Suggested guidelines for the diagnosis and management of urea cycle disorders
Diagnostic algorithm for neonatal hyperammonemia. Unless indicated, plasma is used for the analytical determinations. Non-standard abbreviations include: A-FP, α fetoprotein; CIT 2, citrullinemia type 2; CPSD, CPS1 deficiency; HI-HA, hyperinsulinism-hyperammonemia syndrome; HMG, 3-hydroxy-3-methylglutaryl-CoA lyase deficiency; LPI, lysinuric protein intolerance; OATD, ornithine aminotransferase deficiency; PA, propionic acidemia; PC, pyruvate carboxylase; P5CSD, Δ1-pyrroline-5-carboxylate deficiency; THAN, transient hyperammonemia of the newborn; TPD, trifunctional protein deficiency; U, urine. Grade of recommendation, D. * In some patients with late-onset OTCD, plasma citrulline levels are in the lower part of the normal range.