Bone health in patients with inborn errors of metabolism

Abstract

Inborn errors of metabolism encompass a wide spectrum of disorders, frequently affecting bone. The most important metabolic disorders that primarily influence calcium or phosphate balance, resulting in skeletal pathology, are hypophosphatemic rickets and hypophosphatasia. Conditions involving bone marrow or affecting skeletal growth and development are mainly the lysosomal storage disorders, in particular the mucopolysaccharidoses. In these disorders skeletal abnormalities are often the presenting symptom and early recognition and intervention improves outcome in many of these diseases. Many disorders of intermediary metabolism may impact bone health as well, resulting in higher frequencies of osteopenia and osteoporosis. In these conditions factors contributing to the reduced bone mineralization can be the disorder itself, the strict dietary treatment, reduced physical activity or sunlight exposure and/or early ovarian failure. Awareness of these primary or secondary bone problems amongst physicians treating patients with inborn errors of metabolism is of importance for optimization bone health and recognition of skeletal complications.

Evaluation of Body Composition, Physical Activity, and Food Intake in Patients with Inborn Errors of Intermediary Metabolism

“…Nonetheless, in our series, despite significant positive correlations between weight and BMI measured at almost all bone sites, total body BMD and BMD measured at the femoral neck, femoral trochanter, and Ward’s triangle were lower in IEiM patients than healthy controls. Factors proposed to contribute to reduced bone mineralization in IEiM include nutritional deficiencies linked to the dietary regimens of patients with these diseases, reduced physical activity and sunlight exposure, and early ovarian failure [ 11 ]. We observed a significant negative correlation between age and BMD measured in the lumbar spine, femur, and trochanter.…”

“…Dietary recommendations for IEiM patients ( Supplementary Table S1 ) are based on or extrapolated from estimated requirements for healthy populations, including recommendations from the World Health Organization (WHO) [ 10 ]. However, because IEiM diets often diverge from recommendations for natural food and energy intake, their impact on long-term growth and body composition necessitates ongoing assessment [ 11 , 12 , 13 ]. Effective treatment requires an understanding of both the biochemistry of metabolic defects and the individual nutritional requirements in order to provide an adequate intake and maintain the metabolic balance [ 14 ].…”

Skeletal Biology and Disease Modeling in Zebrafish

“…Metabolic and hormonal problems cause a wide range of human disorders that frequently involve bone. ( 212 ) Several related bone disease models, eg, mimicking osteoporosis‐like phenotypes, have been developed in zebrafish, ( 213 ) often by using unique anatomical bone structures such as exoskeletal zebrafish fin rays or scales. ( 214 )…”

Phenylketonuria, co‐morbidity, and ageing: A review

“…In summary, there is currently no conclusive evidence indicating a higher fracture risk in ETAwPKU, but the effect of ageing on fracture rate cannot yet be established. 27…”