ALPHA-MANNOSIDOSIS: WHAT IS ALPHA-MANNOSIDOSIS?
Definition: What is "Alpha-mannosidosis"?
Alpha-mannosidosis is an "autosomal recessive metabolic disorder" that leads to physical & mental deterioration. When the a-mannosidase enzyme becomes defective, it causes impaired cell function & sugar buildup. Since this enzyme normally helps in breaking down complex sugars, absence of this functional enzyme may lead to death on children caused by deterioration of the central nervous system.
Symptoms & Signs
Patients with alpha-mannosidosis experience cerebral symptoms, including brain dysfunction & gait. For mentally retarded patients, learning problems may also occur. However, these problems can be reduced by enrolling children in special schools taught by professional teachers. Some patients may also experience hearing loss & problems with transferring sound through the middle ear, which are both caused by nerve dysfunction. Because of this, patients may also experience a delay in ability of speech, including restricted vocabulary, incomplete sentences & understanding of abstracts. Majority of patients with alpha-mannosidosis has recurrent infections. These infections may affect the middle ear, gastrointestinal tract & the upper or lower respiratory tract. Skeletal malformation can also be seen in the spine of the chest, which may result in back pain & deformed spine. This condition also causes damages to the joints with symptoms resembling rheumatoid arthritis. Patients may also develop muscle weakness & pain, which could lead to total immobilization.
Diagnosis is made by measuring the enzyme activity in white blood cells & measuring substances in urine. Although diagnosis is usually made late, symptoms are often mild. However, biochemical diagnosis is difficult, so most cases are under diagnosed.
Alpha-mannosidosis occurs in 1 in 500,000 worldwide. This disease is found in all ethnic groups in America, Asia, Africa & Europe.