Signs and symptoms vary amongst people who have the condition. In general, affected individuals may have intellectual disability, distinctive facial features, immunodeficiency, hearing impairment and skeletal abnormalities.1
Characteristic facial features can include a large head, prominent forehead, low hairline, rounded eyebrows, large ears, flattened bridge of the nose, protruding jaw, widely spaced teeth, overgrown gums, and large tongue.2
Learn moreAt least three clinical types of Alpha Mannosidosis (mild, moderate, and severe) have been suggested, classified according to the severity of the symptoms.3
A mild form, clinically recognized after ten years of age, with absence of skeletal abnormalities, and very slow progression.
A moderate form, recognized before 10 years of age, with presence of skeletal abnormalities, slow progression and development of ataxia at age 20-30. This is the most common form.
A severe form, immediately recognized with skeletal abnormalities, and obvious progression, leading to an early death from primary central nervous system involvement or myopathy.
However, given the variety of mutations that have been documented, the broad range and severity of symptoms, and no link between particular mutations and symptomatology, the disease is considered clinically as a continuum, from mild to severe.4,5
Conductive and neurosensory
Celebral atrophy and demyelination
Mental retardation (>90%)
• IQ 60-80
• Delayed development of speech
• Delayed motor and mental function
• Large head and prominent forehead
• Flattened nasal bridge
• Prognathism
• Short neck
• Leading to frequent infections
• Genu valgus
• Joint contractures
The information on this website is intended only to provide knowledge of Alpha Mannosidosis disease health topics. This information should not be used in place of advice from your GP or other healthcare professional. If in doubt please contact your doctor for advice. This website has been produced by Chiesi Pharmaceuticals. The website has been developed in accordance with industry and legal standards to provide information for healthcare professionals and the general public about Alpha Mannosidosis disease health topics. Chiesi Pharmaceuticals makes every reasonable effort to include accurate and current information. However, the information provided in this website is not exhaustive.