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Published on: November 25, 2017
[Beta mannosidosis: a new case]
E Gourrier1, M P Thomas, A Munnich
1Service de néonatologie et réanimation, hôpital René-Dubos, Pontoise, France.
Insights
Beta mannosidase deficiency is a rare genetic disorder. This case highlights swallowing and esophageal motility issues in a patient with beta mannosidosis, leading to recurrent infections.
Area of Science:
- Biochemistry
- Genetics
- Pediatrics
Background:
- Beta mannosidase deficiency is an extremely rare lysosomal storage disorder.
- Only 11 cases have been previously reported in medical literature.
- This report details a new case, expanding the known clinical spectrum.
Background:
Only 11 cases of beta mannosidase deficiency have been reported until now. We report a new case.
Case History:
J was born at full term to consanguineous parents; her weight was 2,080 g and her height was 44 cm. During the first months of life she was hypotonic and had feeding difficulties. At the age of 7 months, she was admitted to an intensive care unit because of a serious inhalation. Standard blood analysis, chest X-ray, abdominal ultrasonography, electroencephalogram, cerebral nuclear magnetic resonance and electromyography were normal. Blood and urine amino acids and urine organic acids were also normal. The only detected abnormality was a marked deficiency of beta mannosidase in her serum and leukocytes. Later on, she suffered from recurring respiratory infections, and she had abnormalities of esophageal mobility, hypotoria of the lower esophageal sphincter, and at the age of 2 years, achalasia requiring surgery. To date, her motor development is retarded.
Conclusions:
The main clinical manifestations of beta mannosidosis are various degrees of mental retardation, speech disorders and hearing loss. Our patient presented with abnormalities of swallowing and esophageal motility resulting in recurring respiratory infections, previously reported in some other cases.
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