Cause
MPS is hereditary. In nearly all cases a child receives a recessive gene from each parent. MPS II is the only exception where the gene may be passed from a mother to her male children. A couple’s chance of having another child with one of these disorders is 1 in 4 with each pregnancy. Unaffected siblings may be gene carriers of the disorder.
The occurrence of MPS in the general population is thought to be one in 25,000 births.
Symptoms
While the symptoms of the diseases may vary from one syndrome to another, there are similarities. Affected individuals may have mental retardation, cloudy corneas, short stature, stiff joints, incontinence, speech and hearing impairment, chronic runny nose, hernia, heart disease, hyperactivity, depression, pain and a dramatically shortened life span.
Diagnosis
Diagnosis for these disorders is often delayed because of the heterogenous nature of MPS and also because the initial symptoms may be perceived as common medical problems that children of similar age experience. In addition, because these children have various seemingly unrelated medical problems, they often receive care from a number of independent specialists (cardiologist, ophthalmologist, orthopedist, etc.), further delaying an appropriate diagnosis.
