Diagnosis and Treatment

Mucolipidosis Type IV (MLIV) is characterized by:

Psychomotor delays, similar to cerebral palsy
Cognitive delays
Children typically reach a maximum developmental age of 18-24 months in expressive language and fine motor function
Receptive language abilities are better than expressive abilities
Hypotonia (low muscle tone), but tendon reflexes are usually spastic
Corneal clouding
Pseudo-strabismus (false appearance of crossed eyes)
Progressive retinal degeneration, resulting in blindness by late teenage years
MRI of the brain typically shows a thin corpus collosum, and delayed growth in white matter of brain (myelination)
Achlorhydria (lack of acid in the stomach)
Elevated gastrin levels in stomach
Anemia (iron deficiency)
Individuals with MLIV typically survive to early adulthood

Some children with MLIV may appear with a milder presentation early in life marked by the ability to walk (assisted or unassisted), crawl, and speak a few words. Typically, these skills are lost in the second decade as the disease progresses.

DIAGNOSIS

Individuals with clinical findings (symptoms) for MLIV can have a simple blood test to check for elevated gastrin levels.
Molecular genetic testing will confirm the diagnosis in most individuals.
Two mutations of the gene account for a majority of mutations in individuals of Ashkenazi (Eastern European Jewish) heritage. However, increasingly, many new mutations account for a great number of newly diagnosed individuals.

TREATMENT

There is no medical treatment available at the present time.
Intensive physical therapy for spasticity and ataxia is highly recommended for acquisition of speech, feeding, and motor skills, and prevention of secondary complications such as tightened ligaments and difficulties with balance.
Some individuals may develop the ability to sit independently or crawl. Some have learned to walk with the aid of ankle-foot orthotics (AFO’s) and gait trainers.
Occupational, speech, and vision therapies are also highly recommended to improve life skills.
Spoken language is usually limited to a few or no words. Many individuals use some sign language to communicate.
Some children have had success with the use of “auditory scanning” to make choices.
Iron supplements may be important to prevent anemia.
Pureed foods and thickened liquids can be necessary to prevent choking and aspirating while eating as children progress into early adulthood.
Botox can be useful for managing tightness and tone. If tone becomes pervasive and too encompassing for localized botox injections, some families have found Baclofen to be useful in bringing overall tone down. With overall tone reduced, botox can still be useful.