TTR and metabolic acidosis: Other BTHS phenotypes include a range of metabolic aspects, such as 3-methylglutaconic aciduria, low prealbumin levels, decreased cholesterol in low-density lipoprotein, hypocholesterolemia, mildly elevated creatine kinase, hyperlactacidemia, lactic acidosis, metabolic acidosis, hypoglycemia, reduced plasma carnitine levels, raised serum transaminases, and mild hyperammonemia (Kelley et al, 1991; Donati et al, 2006; Spencer et al, 2006; Clarke et al, 2013).