Symptoms and red flags

Alpha-mannosidosis is a rare lysosomal storage disorder that generally presents in early childhood. It is a progressive, highly heterogeneous disease that is difficult to recognize, and a diagnosis is usually reached after referrals to multiple specialists.1

Multi-disciplinary approach and early diagnosis in alpha-mannosidosis

Patients may present a continuum of clinical findings: most children appear normal at birth but clinical manifestations begin at a very early age followed by progression of clinical symptoms.2, 3

The rare, highly heterogeneous nature of alpha-mannosidosis hampers diagnosis, which is often delayed or overlooked: the disease is underdiagnosed and the long-term prognosis for untreated alpha-mannosidosis is poor.1

Therefore, in order to offer the patients a therapy as personalized as possible and aimed to improve their condition or to slow down the progression of the disease, a multi-disciplinary approach is crucial for diagnosis and disease management.1

Together with the multi-disciplinary approach, early diagnosis remains the best mean of initiating prompt treatment and minimising progressive symptoms.3

Early diagnosis of alpha-mannosidosis is important for genetic counseling because there is a 25% risk of disease recurrence (autosomal recessive disease), and parents can undergo prenatal or preimplantation diagnosis procedures.4

Recognising “red flags” to aid early diagnosis in alpha-mannosidosis

In alpha-mannosidosis, some of the main clincal features are:2, 5, 6

  • hearing loss;
  • skeletal involvement;
  • cognitive impairment;
  • immunodeficiency;
  • recurrent infections.
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  1. Verrecchia, E. et al. Caregivers’ and Physicians’ Perspectives on Alpha-Mannosidosis: A Report from Italy. Adv Ther 38, 1–10 (2021).
  2. Malm, D. & Nilssen, Ø. Alpha-mannosidosis. Orphanet Journal of Rare Diseases 3, 21 (2008).
  3. Guffon, N. et al. Recognition of alpha-mannosidosis in paediatric and adult patients: Presentation of a diagnostic algorithm from an international working group. Molecular Genetics and Metabolism 126, 470–474 (2019).
  4. Lehalle, D. et al. Hearing impairment as an early sign of alpha-mannosidosis in children with a mild phenotype: Report of seven new cases. Am J Med Genet A 179, 1756–1763 (2019).
  5. Borgwardt, L. et al. Alpha-mannosidosis: correlation between phenotype, genotype and mutant MAN2B1 subcellular localisation. Orphanet J Rare Dis 10, 70 (2015).
  6. Beck, M. et al. Natural history of alpha mannosidosis a longitudinal study. Orphanet J Rare Dis 8, 88 (2013).

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.