Osteopetrosis( or marble disease) is a severe congenital skeletal disease characterized by excessive ossification( generalized or localized).In most known cases, pathology is inherited. Very rarely the disease occurs in a healthy family.
Pathology was first studied and described by the German doctor Albers-Schoenberg in 1904.In the literature, marble osteopetrosis is also known as congenital systemic osteosclerosis. In children, the diagnosis is made almost immediately after birth. The disease is severe, and deaths are frequent. With an easier flow, osteopetrosis is only determined in adulthood and is usually an accidental finding in radiography due to a fracture of the bones.
For many years scientists can not agree on the etiology of Albers-Schoenberg disease. It is believed that the body starts pathological processes that interfere with the normal absorption of calcium and phosphorus. Serious disturbances in the exchange of minerals lead to the appearance of a disease called osteopetrosis. What is it and why the mechanism of destruction of bone tissue is activated, it is not possible to find out.
In most cases, it is possible to trace the unique hereditary nature of the disease. Osteopetrosis( "deadly marble") can be transmitted both autosomal dominant and autosomal recessive. In the first case, pathology is detected already in adulthood and passes relatively easily. In the recessive transmission of the trait, Albers-Schoenberg disease is diagnosed immediately after birth and proceeds with a large number of complications.
How does the pathology develop?
The pathogenesis of osteopetrosis has not been studied enough. It is assumed that the normal interaction between the bone and hemopoietic tissue is still in utero. Osteoclasts - the cells responsible for the destruction of the skeleton - do not fulfill their function. As a result, the structure of bones changes, they deform and cease to cope with their task. In addition, the blood supply and innervation of the skeleton is significantly impaired. Most often affected are long tubular bones, bones of the skull, pelvis and spine.
Classification of osteopetrosis
- Autosomal recessive form( develops from birth, proceeds with severe complications and frequent fatal outcome).
- Autosomal dominant form( revealed in adulthood, has a benign course).
Osteopetrosis - what is it? Symptoms of the disease
In the recessive path of transmission, the first signs of pathology appear immediately after birth. Boys and girls get sick the same way. The face of the child has a characteristic appearance: broad cheekbones, far-apart eyes from each other. The root of the nose is always impressed, the nostrils are turned outward, the lips are thick. Soon, progressive anemia and hydrocephalus develop, there is a pronounced increase in the liver and spleen. Very often hemorrhagic diathesis occurs. The inevitable ending is the multiple defeat of bones. When the process spreads onto the cranial box, the visual and auditory nerves are compressed, blindness and deafness develop.
Osteopetrosis is a lethal process affecting almost all long tubular bones. Most children do not live up to 10 years. Develops purulent osteomyelitis of bone tissue, leading to disability. The cause of death, as a rule, is severe anemia and sepsis.
With the dominant variant, pathology is detected in school-age children, as well as in adults. As a rule, the patient does not even suspect that such an insidious disease has settled in his body. Osteopetrosis is usually an accidental finding in radiography for bone fracture. In many cases, the pathology is completely asymptomatic. Some patients complain of periodic pains in the bones, others become frequent clients of traumatologists, continually getting on the operating table with pathological fractures. Anemia, as a rule, is negligible, neurological disorders due to compression of nerve fibers are rare.
With mild forms of Albers-Schoenberg disease, there is no mental abnormality in development. Very characteristic for this pathology is the later teething, their incorrect development, the tendency to caries. Low growth at birth is not inherent, the lag in physical development is revealed closer to a year.
Osteopetrosis( death marble).Diagnostics
In the case of early development of pathology, a small patient falls into the hands of doctors in the first months of life. In this case, diagnosis is usually not particularly difficult. The characteristic appearance of the patient makes it possible to suspect osteopetrosis. At the older age, patients are usually already registered with an orthopedic surgeon due to frequent fractures. In adults, the clinical picture is smeared, many signs do not appear, which makes it difficult to diagnose.
In all cases, irrespective of age, an X-ray examination can confirm or disprove osteopetrosis. What is this and what is the meaning of the method? In a specially equipped office, a photograph of the affected area is made in two projections. Radiographs clearly show the compaction of bones, with the border between tubular and spongy substances absent. The bones are deformed, the metaphyses( areas near the joints) are significantly enlarged. Usually, the spine, skull and pelvis are involved in the process. The wavy course of the disease provides a transverse striation of the vertebrae and long tubular bones, which is clearly visible on the X-ray.
Treatment of osteopetrosis
Radical healing from this severe disease has not been developed. Treatment is mainly symptomatic, aimed at improving the general condition and improving the quality of life. If the Albers-Schoenberg disease is detected at an early age, the patient can undergo bone marrow transplantation. This is a relative new procedure that allows to save a child's life even in case of severe skeletal lesions. The earlier the bone marrow transplant is performed, the more chances for a successful outcome of the disease.
For the operation, it is required to obtain material from a close relative with which the patient will show maximum compatibility for HLA-genes. Otherwise, the bone marrow will not survive, serious complications that threaten the patient's life will arise. To determine compatibility, special blood tests are performed to determine the similarity of the genome of the donor and recipient.
With a successful outcome of the operation, the structure of bone tissue is gradually restored. There is an improvement in the general condition, vision and hearing are normalized. Transplantation is the only chance for those patients who have not received any visible results from other treatments.
The transplantation of bone marrow stem cells is also a very promising direction for healing from a disease such as osteopetrosis. What it is? In this case there is a transplantation not only of the organ, but only of individual cells. They take root in the patient's bone marrow and restore normal hematopoiesis. This procedure is much easier to tolerate by small patients, since it does not require intravenous anesthesia.
For the treatment of adults, calcitriol or γ-interferon is used, which normalizes the activity of osteoclasts, thereby inhibiting the process of destruction and compaction of bone tissue. Such therapy can significantly reduce the risk of new fractures, which has a positive effect on the quality of life of the patient.
Frequent fractures of long tubular bones are a problem that sooner or later every patient faces. The hip suffers the most, the injuries to the lower jaw, spine, and thorax are not excluded. Against the background of the disturbed hematopoiesis process develops purulent osteomyelitis, which is difficult to treat. Expressed deformities of the limbs - the inevitable result of a serious illness called osteopetrosis. Photos of the consequences of this pathology look dignifiedly scary.
The course of the disease largely depends on the age of the patient. In some cases, the development of pathology can suddenly stop and not remind yourself of anything for many years. In other cases, the disease progresses with severe anemia and frequent purulent infections. The younger the child, the greater the likelihood of serious complications and death. And, on the contrary, in adulthood the disease manifests itself as much less actively, annoying only by the increased fragility of the bones of the skeleton.
Regardless of the severity of the disease, all patients with a confirmed diagnosis should be observed for life at the orthopedist. An experienced doctor will be able to identify any complications that arise in time and, if necessary, assign additional methods of examination and treatment.