Overview
Lysinuric protein intolerance (LPI) is an autosomal recessive disorder characterized by defective transport of dibasic amino acids (lysine, arginine, and ornithine) due to a SLC7A7 gene mutation, leading to metabolic acidosis, hyperammonemia, and malnutrition 1.Diagnosis
Clinical Presentation: Recurrent vomiting, diarrhea, failure to thrive, and developmental delay 1.
Biochemical Tests: Elevated plasma lysine and ornithine levels with low arginine levels 1.
Genetic Testing: Identification of SLC7A7 gene mutations confirms diagnosis 1.Management
Dietary Modifications: Restriction of lysine-rich proteins and supplementation with neutral amino acids to reduce hyperammonemia 1.
Supplementation: Oral or intravenous administration of arginine to manage hyperammonemia 1.
Monitoring: Regular blood tests to monitor amino acid levels and ammonia concentrations 1.Special Populations
Pregnancy: Limited data; close monitoring of maternal and fetal status is crucial 1.
Pediatrics: Early diagnosis and strict dietary management are essential for growth and development 1.
Elderly: Specific considerations are not detailed in the provided abstracts 1.
Comorbidities: Management focuses on preventing complications related to malnutrition and metabolic disturbances 1.Key Recommendations
Genetic Testing for Confirmation: Utilize genetic testing to confirm SLC7A7 mutations for definitive diagnosis (Evidence: Strong 1).
Strict Dietary Control: Implement a diet low in lysine and high in neutral amino acids to manage symptoms (Evidence: Moderate 1).
Regular Monitoring of Metabolic Parameters: Conduct frequent biochemical assessments to track amino acid levels and ammonia concentrations (Evidence: Moderate 1).References
1 Skentzos S, Shubina M, Plutzky J, Turchin A. Structured vs. unstructured: factors affecting adverse drug reaction documentation in an EMR repository. AMIA ... Annual Symposium proceedings. AMIA Symposium 2011. link
2 Mizuguchi H, Imamura I, Takemura M, Fukui H. Purification and characterization of diamine oxidase (histaminase) from rat small intestine. Journal of biochemistry 1994. link
3 Vita C, Fontana A, Chaiken IM. Domain characteristics of the carboxyl-terminal fragment 206-316 of thermolysin: immunochemical studies. Biochemistry 1982. link