Mucopolysaccharidoses

Mucopolysaccharidosis on the nature of the emerging changes in the bone system are related to diseases in which the epiphyses of the bones are affected. It is with this circumstance that difficulties in their recognition are associated, since they have great similarity with other epiphyseal dysplasias. In some cases, when there is no possibility of a fuller examination of persons with the existing pathology of the musculoskeletal system in a hospital, an incorrect diagnosis is possible. This leads to incorrect orthopedic treatment and medical and genetic counseling on issues of further childbearing. All mucopolysaccharidoses are divided into two groups, depending on the manifestations of this pathology that appear in humans: Hurler-like and Morkio-like.

All possible manifestations of mucopolysaccharidosis in the Hurler-like group are of the same type and differ among themselves to a greater extent only in the severity of the manifestation. In the case of such a disease, children are born absolutely normal, and over time, various bone deformations gradually begin to appear and progressively increase. Such children are often ill with respiratory diseases, they have chronic rhinitis, it can be noted the appearance of noisy breathing. Subsequently, the gap between children in growth from peers becomes more obvious. They have a short neck, shoulder blades are located higher than in healthy children. Gradually appear and constantly progressing rough features( Hurler-like face), contractures in the joints. First of all, the upper limbs are affected: the fingers of the hands are bent, the brushes become wide, strong, they do not have the possibility of extension. Under the influence of contractures in the joints of the lower extremities in children there is a change in gait: they walk on bent legs, often on "tiptoes".Such changes in the musculoskeletal system are combined with various extra-skeletal changes.

Radiographic examination reveals the most characteristic changes of the pelvis, hip joints and hands for the given disease. The pelvis is squeezed from the sides, the thighs are small in size, flattened, the thighs are thin. In the study of the bones of the hand, the delay in the appearance of the nuclei of ossification of the bones of the wrist is revealed, the metacarpal bones become short and wide, the phalanges of the fingers are wide, the nail phalanges are hypoplastic.

There are several variants of mucopolysaccharidosis in the Hurler-like group.

The most severe mucopolysaccharidosis type 1Н. The first manifestations of this disease appear in the first months of the child's life and rapidly progress. There is a sharp decline in mental development. By 2-3 years, a typical picture of the disease develops. But we must remember that manifestations of mucopolysaccharidosis type 1Н in the first year of life are very similar to manifestations of congenital hypothyroidism. In the case of hypothyroidism, the child also has a mental retardation. The appearance of such children is also characteristic: a puffy face, the tongue is often stuck out, large, the skin is dry, the child is overweight, moves very little, frequent constipations are observed. Early detection of hypothyroidism is necessary to initiate early treatment, since children who begin to receive treatment during the first half of life can develop completely normally, which does not occur in the event of a later onset of treatment.

Another type of mucopolysaccharidosis from the Hurler-like group is similar in pattern to bone changes to type 1H.The difference is that only boys always suffer, most of which have blond hair and dark, thick brows. This type of mucopolysaccharidosis is characterized by the disappearance of coordination of movements to 2-6 years. The child thus often begins to fall when walking. The behavior of children becomes uneven, and in some cases even aggressive. They do not eat strong food. Between the shoulder blades, some children can see the appearance of nodular skin lesions. The facial features do not change as dramatically as with the above-described form of mucopolysaccharidosis.

In mucopolysaccharidosis type IS, which also belongs to this group of mucopolysaccharidoses, the first signs appear late, usually at 3-6 years of age, and develop extremely slowly. The full picture of the disease is revealed by the time of sexual maturity of the child. In adolescence, when the oculist is examined, the opacity of the cornea is often seen. The increase in the size of the liver and spleen is rare. For this type of mucopolysaccharidosis, aortic valve lesion is typical, which is manifested by characteristic signs of this disease. Mental development of children is reduced not so much, and sometimes does not suffer at all. The defeat of the osteoarticular system with this disease in severity is the easiest of all mucopolysaccharidoses of the Hurler-like type.

The next type of mucopolysaccharidosis from the Hurler-like group is the mucopolysaccharidosis type VI - the Maroto-Lamy syndrome .The first signs of this syndrome appear after 2 years of age and by 7-9 years become very characteristic. Such children reach a height of not more than 145-155 cm. They also have gross facial features, but not so much as with type VI mucopolysaccharidosis, joints are expressed in contractures, children are "hooked" in the course of making any movements. A characteristic feature of this type of mucopolysaccharidosis is that, despite the sharp manifestation of all the main manifestations, the mental development of children never suffers. The last two considered types of mucopolysaccharidosis are accompanied by all the characteristic changes in the skeleton, indicated above.

Manifestations of Morky-like mucopolysaccharidosis differs sharply from the Hurler-like group. Individuals with this disease of the musculoskeletal system are dwarfs, have specific facial features and a short torso. The first signs of the disease appear after 2 years of age and are rapidly growing. The head is quite large, rough features: widely set eyes, bridge of the saddle of the form, the lower part of the face protrudes. The neck is short, the thoracic cage is keel-shaped, many children have a curvature of the spine. The blades are unusually high, the forearm bones are deformed, the brushes are soft. The wrist, knee and ankle joints are enlarged in size. This is particularly noticeable due to the low weight of these children due to a decreased appetite. The lower limbs are twisted, the feet are spread out. Children quickly get tired, gait deteriorates rapidly, and many stop walking because of bone marrow damage due to its compression. Radiographic examination reveals the underdevelopment or complete absence of the dentate process of the 2nd cervical vertebra, as well as signs of instability of the articulation of the first cervical vertebra with the skull. There is a universal platiposition. Changes in the pelvic bone are also characteristic. Cervical hips valgus, their heads sharply flattened and, as it were, divided into several fragments. Changes in the hands are similar to those in the Hurler-like group of mucopolysaccharidosis.

In this disease, in addition to the bone system, connective tissue, which forms the basis of various internal organs and systems, suffers. Often, children do not hear well because of the development of their early hearing loss. In addition, there is a tendency to frequent colds. Quite often, children with mucopolysaccharidosis develop umbilical and( or) inguinal hernias. Intellect in most cases remains normal. In some of the sick children, changes are detected from the side of the cardiovascular system, an increase in the liver, and more rarely a spleen. Especially pronounced changes from the eyes: corneal lesion, most often detected when viewed by the oculist with a slit lamp.

One of the most informative methods for diagnosing mucopolysaccharidosis is the study of the structure of connective tissue cells. The most accessible material for such a study is the skin.