Morquio syndrome

Morquio's syndrome (referred to as mucopolysaccharidosis IV or Morquio's) is an autosomal recessive mucopolysaccharide storage disease (see also lysosomal storage disorder), usually inherited. It is a rare type of birth defect with serious consequences. When the body cannot process certain types of mucopolysaccharides, they build up or are eliminated, causing various symptoms.

It involves accumulation of keratan sulfate.

History
The condition was first described, simultaneously and independently, in 1929, by Luis Morquio in Montevideo, Uruguay and James Frederick Brailsford in Birmingham, England.

They both recognized the occurrence of corneal clouding, aortic valve disease, and urinary excretion of keratan sulfate. Morquio observed the disorder in 4 siblings in a family of Swedish extraction and reports his observations in French.

Symptoms
The following symptoms are associated with Morquio's syndrome:


 * Abnormal heart development
 * Abnormal skeletal development
 * Hyper mobile joints
 * Large fingers
 * Knock-knees
 * Widely spaced teeth
 * Bell shaped chest (ribs flared)
 * Compression of spinal cord
 * Enlarged heart
 * Dwarfism

Patients with Morquio's syndrome appear healthy at birth. They often present with spinal deformity, there is growth retardation or genu valgus in the second or third year of life.


 * Short stature (flat vertebrae cause a short trunk), short neck
 * Moderate kyphosis or scoliosis
 * Mild pectus carinatum (pigeon chest)
 * Cervical spine: odontoid hypoplasia, atlanto-axial instability; may be associated with myelopathy with gradual loss of walking ability
 * Joint laxity, mild dysostosis multiplex, dysplastic hips, large unstable knees, large elbows and wrists, and flat feet
 * The combined abnormalities usually result in a duck-waddling gait
 * Mid-face hypoplasia and mandibular protrusion
 * Thin teeth enamel
 * Corneal clouding
 * Mild hepatosplenomegaly

Treatment
The treatment consists of prenatal identification and of enzyme replacement therapy.