About morquio disease

What is morquio disease?

Morquio syndrome (mucopolysaccharidosis type IV; MPS IV) is a mucopolysaccharide storage disease that exists in two forms (Morquio syndromes A and B) and occurs because of a deficiency of the enzymes N-acetyl-galactosamine-6-sulfatase and beta-galactosidase, respectively. A deficiency of either enzyme leads to the accumulation of mucopolysaccharides in the body, abnormal skeletal development, and additional symptoms. In most cases, individuals with Morquio syndrome have normal intelligence. The clinical features of MPS IV-B are usually fewer and milder than those associated with MPS IV-A. Symptoms may include growth retardation, a prominent lower face, an abnormally short neck, knees that are abnormally close together (knock knees or genu valgum), flat feet, abnormal sideways and front-to-back or side-to-side curvature of the spine (kyphoscoliosis), abnormal development of the growing ends of the long bones (epiphyses), and/or a prominent breast bone (pectus carinatum). Hearing loss, weakness of the legs, and/or additional abnormalities may also occur.

The mucopolysaccharidoses (MPS) are a group of inherited lysosomal storage disorders. Lysosomes function as the primary digestive units within cells. Enzymes within lysosomes break down or digest particular nutrients, such as certain carbohydrates and fats. In individuals with MPS disorders, deficiency or malfunction of specific lysosomal enzymes leads to an abnormal accumulation of certain complex carbohydrates (mucopolysaccharides or glycosaminoglycans) in the arteries, skeleton, eyes, joints, ears, skin, and/or teeth. These accumulations may also be found in the respiratory system, liver, spleen, central nervous system, blood, and bone marrow. This accumulation eventually causes progressive damage to cells, tissues, and various organ systems of the body. There are several different types and subtypes of mucopolysaccharidosis. These disorders, with one exception, are inherited as autosomal recessive traits.

What are the symptoms for morquio disease?

Mucopolysaccharidosis type IV (MPS IV), also known as Morquio syndrome, is a rare metabolic condition in which the body is unable to break down long chains of sugar molecules called glycosaminoglycans. As a result, toxic levels of these sugars accumulate in cell structures called lysosomes, leading to the various signs and symptoms associated with the condition. Affected people generally develop features of MPS IV between the ages of 1 and 3. These signs and symptoms may include abnormalities of the skeleton, eyes, heart and respiratory system. 

What are the causes for morquio disease?

There are two forms of MPS IV:

  • MPS IVA is caused by changes (mutations) in the GALNS gene.
  • MPS IVB is caused by mutations in the GLB1 gene.

Both forms are inherited in an autosomal recessive manner

What are the treatments for morquio disease?

Morquio disease is a rare inherited metabolic disorder in which the body has trouble processing specific kinds of sugar molecules (glycosaminoglycans). This condition, also known as mucopolysaccharidosis type IV (MPS IV), manifests as a skeletal disorder with aberrant spine curvature, a short neck, knock knees, and hip issues. Children who are affected by the syndrome may exhibit an expanded head and recognisable facial features. Infants with the disease are typically diagnosed. For the management of the physical repercussions, supportive care is necessary. This condition has no effect on intellectual ability. Treatment for the morquio disease Since morquio disease can impact a number of different physiological systems, there are numerous treatment options available. The type of care a child needs is determined by how severe his symptoms are. Some kids might merely need attentive supervision. To treat particular parts of their ailment, others could require non-surgical or surgical procedures. Because every child's condition is unique, the best course of action is chosen for each individual youngster. Orthopaedic issues such as scoliosis, kyphosis, skeletal dysplasia, narrow chest, joint problems, and limb deformities are often diagnosed in children with morquio disease. These problems can sometimes be treated when a child is very small even though they are present at birth. For affected individuals with ventricular hypertrophy, the installation of a bioprosthetic or prosthetic valve may be necessary (overgrowth). It could be necessary to remove enlarged tonsils and adenoids to treat upper airway blockage and sleep apnea. For those who have hearing loss, ventilation tubes and hearing aids could also be required. When the cornea becomes scarred or cloudy, a procedure called penetrating keratoplasty (corneal replacement) may be required to restore eyesight

What are the risk factors for morquio disease?

An uncommon genetic birth condition called morquio disease is estimated to influence one in every 200,000 babies. The condition may not be evident at birth, and symptoms typically appear between the ages of one and three. The symptoms of morquio disease worsen as a child gets older because it is a progressive illness. A mucopolysaccharidosis is a group of diseases that includes morquio disease (MPS). MPS IV is another name for morquio disease. Children with morquio disease are unable to break down glycosaminoglycans, which are sugar chains that are essential for the development of connective tissue, bone, cartilage, and the corneas of the eyes (such as tendons, ligaments, etc.). Risk factors for morquio disease These are risk factors for the morquio disease- An individual will be a carrier for the disease but will not exhibit any symptoms if they inherit one normal gene and one disease gene. With each pregnancy, there is a 25% chance that two carrier parents will carry the faulty gene to their offspring as well. With each pregnancy, there is a 50% chance that the child will carry the same gene as one of the parents. A child has a 25% probability of inheriting normal genes from both parents and being genetically normal for that specific trait. Both men and women are at the same level of danger. All people have four to five defective genes Consanguineous parents are more likely than unrelated parents to share a defective gene, which raises the likelihood that their offspring may develop a recessive genetic condition. As your child gets older, the morquio disease's problems might not be as obvious or troublesome. This frequently holds for joint problems, limb deformities, and spine malformations.

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