Lysinuric protein intolerance
is a metabolic disorder caused by the body's inability to digest and use the amino acids lysine, arginine, and ornithine. Because the body cannot effectively break down these amino acids, which are found in many protein-rich foods, individuals experience nausea and vomiting after ingesting protein. Other features associated with protein intolerance may also occur, including short stature, muscle weakness, impaired immune function, and osteoporosis. A lung disorder called pulmonary alveolar proteinosis may develop in some individuals, as can end-stage renal disease, coma and intellectual disability. Symptoms usually develop after infants are weaned and begin to eat solid foods. Lysinuric protein intolerance is caused by mutations in the SLC7A7 gene. It is inherited in an autosomal recessive manner. Source: Genetic and Rare Diseases Information Center (GARD), supported by ORDR-NCATS and NHGRI.