Internal Medicine

0521779407-16 CUNY1086/Karliner 0 521 77940 7 June 4, 2007 21:18

1098 Osteogenesis Imperfecta

Genetic Testing

■Gene sequencing to determine type I collagen alpha 1 or alpha 2

mutations:

■Large genes, 50 exons

■Collagen protein analysis: obtain skin biopsy: culture fibroblasts

■Prenatal diagnosis: Ultrasound at 16–18 weeks; chorionic villus sam-

pling, amniocentesis with DNA testing

differential diagnosis

■Infants and Children:

➣Thanatophoric dwarfism

➣Achondroplasia

➣Hypophosphatasia: severe perinatal and infantile

■Teenagers

➣Idiopathic juvenile osteoporosis

➣Occult endocrinopathy

➣Leukemia, lymphoma

➣Malabsorption syndromes

■Adults

➣Hypophosphatasia: adult, recessive

➣Osteomalacia

➣Idiopathic osteoporosis

➣Endocrinopathy

➣Malignancy: multiple myeloma, leukemia, lymphoma

management

■Team Concept

➣Orthopedic

➣Medicine

➣Physical therapy

➣Social support

specific therapy

Fracture Treatment

■Scoliosis surgery advised to limit deterioration of pulmonary func-

tion

■Fixed and extensible rods to correct deformities, improve function

and assist ambulation: advise rodding when function requires inter-

vention

Medical

■Maintain calcium and vitamin D intake appropriate for age and

weight.