General management of alpha-mannosidosis
There is currently no cure for alpha-mannosidosis. To date, management of the disease has focused on treating individual symptoms, improving quality of life, and preventing the development of further complications.4
After a full physical examination, physicians should focus on the known complications of alpha-mannosidosis, such as hydrocephalus, otitis media, hearing loss, dental caries, joint symptoms, kyphoscoliosis, and diminished mental state.4
A multidisciplinary care team is key to patient care.
This typically includes4,7,10:
Primary Diagnosticians/Managers
Neurologist/
Pediatric neurologist
Pediatric
neurodevelopmentalist
Geneticist
Pediatrician
Pulmonologist
Secondary Treaters/Symptom Managers
Ophthalmologist
Dentist
Otolaryngologist/
Hearing specialist/ENT
GI/Nutritionist
Immunologist
Psychiatrist/
Psychologist/Social worker
Orthopedic specialist
Preventive measures and monitoring
Prevention of secondary complications is also a vital part of management of alpha-mannosidosis.4 In this regard, due to immunodeficiency, prophylactic vaccinations are recommended.7
Medical history should be taken once or twice yearly, along with physical examination including7:
- Number and type of infections
- Weight changes
- Headache history
- Growth, giving attention to head circumference
- Otoscopy and audiometry, to detect hearing deficiencies
- Ophthalmoscopy to detect corneal opacities, myopia, hyperopia, and strabismus
- Assessment of liver and spleen size, heart, and lungs
- Orthopedic evaluation, including joint range of motion, joint aches, gait, walking distance, and bone pain
- Neuropsychological testing (including fatigue, irritability, depression, change in social, domestic, and school/work-related activities) to determine functional level
- Diarrhea or incontinence history
Also, full blood work-up and skeletal assessment with plain radiographs (head, knees, spine, and symptomatic sites) are recommended, along with bone densitometry (every 2-5 years to assess osteopenia) and CT of the brain (to evaluate size of ventricles and shape and size of cerebellum if signs and symptoms of hydrocephalus are present).7
Treatment options for alpha-mannosidosis
Hematopoietic stem cell transplantation (HSCT)
With HSCT, functioning donor cells are transferred into the body to produce enzyme which is then taken up by nearby enzyme-deficient host cells.4
The outcomes from HSCT have been reported as variable with mixed reports of the neurocognitive impact of the therapy.4
Before considering HSCT, consider the possible benefits versus the risk of morbidity and mortality. The benefits are greater in younger patients, before the disease has progressed further.4
Enzyme replacement therapy (ERT)
ERT, which involves the in vitro production of the missing enzyme and its subsequent administration to patients via intravenous infusions, is a therapeutic alternative in a number of lysosomal storage diseases.3,4