Overview
Chylomicron retention disease (CMRD), also known as Anderson disease, is a rare autosomal recessive disorder characterized by fat malabsorption, steatorrhea, and failure to thrive, primarily due to mutations in the SAR1B or SARA2 genes affecting Sar1b protein function 123.Diagnosis
Clinical Features: Failure to thrive, chronic diarrhea, steatorrhea, and hypocholesterolemia 12.
Biochemical Tests: Elevated fat content in stool, malabsorption of fat-soluble vitamins 1.
Histopathology: Intestinal biopsies showing enterocyte vacuolization with large cytosolic lipid droplets 1.
Genetic Testing: Sequencing of SAR1B or SARA2 genes to identify specific mutations 123.Management
Dietary Modifications: Low-fat diet with medium-chain triglycerides (MCT) supplementation to improve fat absorption 1.
Vitamin Supplementation: Fat-soluble vitamins (A, D, E, K) to address deficiencies 1.
Monitoring: Regular assessment of growth parameters, nutritional status, and biochemical markers 1.Special Populations
Pediatrics: Early diagnosis and intervention are crucial to prevent growth retardation and developmental delays 1.
Comorbidities: Potential extraintestinal manifestations such as muscular and cardiac abnormalities in SARA2 mutation cases; monitor creatine phosphokinase levels and cardiac function 3.Key Recommendations
Genetic Testing for Diagnosis: Perform genetic sequencing of SAR1B or SARA2 genes in patients with suspected CMRD (Evidence: Strong 123).
Implement Low-Fat Diet with MCT: Recommend a low-fat diet supplemented with medium-chain triglycerides to manage fat malabsorption (Evidence: Moderate 1).
Regular Monitoring of Nutritional Status: Conduct routine evaluations of growth, nutritional markers, and biochemical parameters to guide management (Evidence: Moderate 1).References
1 Cefalù AB, Calvo PL, Noto D, Baldi M, Valenti V, Lerro P et al.. Variable phenotypic expression of chylomicron retention disease in a kindred carrying a mutation of the Sara2 gene. Metabolism: clinical and experimental 2010. link
2 Charcosset M, Sassolas A, Peretti N, Roy CC, Deslandres C, Sinnett D et al.. Anderson or chylomicron retention disease: molecular impact of five mutations in the SAR1B gene on the structure and the functionality of Sar1b protein. Molecular genetics and metabolism 2008. link
3 Silvain M, Bligny D, Aparicio T, Laforêt P, Grodet A, Peretti N et al.. Anderson's disease (chylomicron retention disease): a new mutation in the SARA2 gene associated with muscular and cardiac abnormalities. Clinical genetics 2008. link