Osteogenesis Imperfecta

Stem Cell Therapy for Osteogenesis Imperfecta

Wu Medical Center, Bejing, China

Osteogenesis imperfecta:  Another name is Fragililis ossium.

Symptoms: bones are under mineralized and fracture easily, blue sclera, deafness, joint laxity. It is one type of congenital hereditary disorder which is the result of the mesenchyma organization hypoplasia, the barrier of collagen forms.

Etiology

The disease is a congenital growth barrier and the cause is unclear. Male and female morbidity probability is equal. It is divided into congenital type and hangfire type. Congenital type refers to the disease onset in utero and is divided into the embryo type and the infant type. The disease is serious, with most patients dying during birth or shortly after birth. It is a euchromosome recessive hereditary condition. The hangfire condition is less serious and is divided into child type and adult type. Most patients have long-term survival rates. It is an autosomal dominant inheritance disorder. More than 15% of patients have a family history of the disorder.

Pathological changes

The widespread mesenchymal tissue suppresses the mature collagenous fibres. During the cartilaginea process, zones of epiphyseal cartilage and calcifying cartilage are normal. The osteoblast and the osteoid tissue are scarce in the metaphysis and the bone is small and slender with a longitudinal arrangement. There is no obvious overlapping of the bone trabecula. The formation of the bone intramembrane is affected, the periosteum thickens while the cortical plate becomes weak and lacks angi-lamellar structure, and the Haversian canal's lumens expand. The medullary cavity of the bones has buildup of fat and many fibrous tissues; the bone is shorter than normal, narrow diameter in the middle, while both sides of the bone are expanded. The bones in the cranium are very thin, scattered and irregular calcified foci are visible, the severity of the patient's bones in the cranium looks like a membrane bag, with delayed fontanel closure. The skin and sclerotic lesions also have pathological change.

clinical situation

1. The brittleness of the bones has increased, any slight damage could cause a fracture, and in severe cases the patient could have a spontaneous fracture.

2. There is approximately 90% Blue sclera. This is due to the patient's cornea becoming translucent, can see the Choroidal color.

3. Deafness: Approximately 25% of patients are presented with hearing loss. Hearing loss often appears between the ages of 11 and 40. The reason may be the hardening of the meatus auditorius leading to stirrup pedal plate bony ankylosis and fixture, (the stirrup pedal plate coheres to the fenestra ovalis). But some experts argue that loss of hearing results from pressure put on the auditory nerve at the base of the skull.

4. Excessive joint laxity, especially in the wrists and malleolus joint. The reason is the tendon and ligament's collagenous tissues have growth barriers. May also have genu valgum, flatfoot. Sometimes a routine shoulder dislocation and radial head dislocation occur.

5. The muscles are weak.

6. Head and facial malformation: patient has serious maldevelopment of the cranial bones, the skin of the head had a leathery feel to it, at birth . The cranium is wide, the parietal bone and occipital bone are prominent, both temporal bones are swollen spherically, the frontal bone protrudes outward, both ears are pushed downward, the face is triangular in appearance. Some patients have accompanying hydrocephalus.

7. Poor development of dentition: The development of teeth is not maintained in a healthy manner. The primary and permanent teeth may be affected. The color of the teeth is either yellow or sky grey, tooth decay and early tooth loss frequently occurs.

8. Dwarfism: This occurs because the patient's growth is stunted, coupled with multiple fractures of the spine and lower limbs, and then there is abnormal cicatrization.

9. There is an increase in the width of the scars on the skin. This is caused by the defective collagenous tissue.

Performance: mainly lacks ossein and has universal osteoporosis.

Treatment

1.Stem cell treatment: Using transplantation of mesenchymal stem cells to treat the patient, we can increase the number of osteoblasts to promote bone proliferation and inhibit bone re-absorption, increase the bone's density and promote skeletal repair and regeneration. As a result, we can strengthen the muscles to protect against, and reduce the possibility of fractures.

Calcium medication and vitamin D supplements are given to prevent the fracturing of bones and related complications.

by Drs. Paul Xu, Xiaojuan Wang and Like Wu