Symptoms
In marble bone disease, the disturbed bone structure leads to instability of the bone with an increased susceptibility to fractures. These fractures are characterized by a poor healing tendency, which can lead to a permanent loss of stability in the skeletal system or to repeated fractures. Bone pain may also occur.
The marble bone disease also causes bone proliferation due to the lack of degradation, especially in the area of the skull bone. The bone proliferation in the area of the face leads to a narrowing of the cranial nerves running there. In this way, parts of the nerves that are responsible for our mimic muscles or for the perception of our sense of hearing and balance can be pinched off.
The result would be a lack of expressiveness in the representation of emotions by the paralyzed facial muscles, hearing loss and dizziness. If the optic nerve is compressed, marble bone disease can lead to blindness in the worst case. The remodelling processes within the bone even extend so far that the bone marrow, which fills the inner spaces of the bones and embodies an important part of our blood formation and defence system, is replaced by bone substance.
As a result of the diminishing bone marrow spaces, marble bone disease stimulates the so-called extramedullary blood formation in the liver and spleen that takes place outside the bone marrow. This form of haematopoiesis occurs naturally in the unborn child in the womb, but after birth it represents a pathological process. An enlarged liver and spleen are therefore also part of the marble bone disease picture.Since the cells of our blood system are also attributed with defense functions during disease processes, the disturbed blood formation leads to a weakened immune defense with increased susceptibility to infections.
The most important mineral for the structure of our skeletal system is calcium. Marble bone disease consumes the calcium reserves of our body and uses them to build up bone substance when there is no degradation. The lack of calcium in the blood can lead to an increased excitability of the musculature, which can appear in the form of cramp attacks. Ultimately, the severity of the symptoms of marble disease can vary greatly depending on which form of the disease is present, i.e. the somewhat milder autosomal dominant or the usually poorly progressing autosomal recessive form of the disease.
