Related Experiment Videos
Mannosidosis in two brothers: prolonged survival in the severe phenotype
Abstract:
Two cases of mannosidosis are reported in brothers, one aged 41 years at death, the other aged 40 years and still alive. These patients are the oldest reported in the literature. Prolonged survival has previously been associated with the milder Type II phenotype. In addition to the characteristic clinical and radiological features of mannosidosis, both had severe joint destruction, which may be related to abnormal lysosomal enzymes in cartilage. The activity of acidic alpha-mannosidase was markedly reduced in plasma, leucocytes and fibroblasts, and the altered kinetic and physical properties are described.
Insights
This study reports two brothers with mannosidosis, the oldest documented cases. Their prolonged survival and severe joint issues highlight the complex nature of this rare lysosomal storage disease.
Area of Science:
- Biochemistry
- Genetics
- Medical Case Reports
Background:
- Mannosidosis is a rare lysosomal storage disease caused by deficient activity of the enzyme acidic alpha-mannosidase.
- It leads to the accumulation of mannose-containing oligosaccharides in various tissues, causing progressive cellular damage.
- Type II mannosidosis is generally associated with a milder clinical phenotype and slower progression.
Observation:
- Two brothers with mannosidosis are presented, with one dying at 41 and the other alive at 40, representing the oldest reported cases.
- Both patients exhibited characteristic clinical and radiological features of mannosidosis, alongside severe joint destruction.
- Reduced activity of acidic alpha-mannosidase was observed in plasma, leucocytes, and fibroblasts.
Findings:
- The patients' prolonged survival suggests a potential link between specific genetic mutations and extended lifespan in mannosidosis.
- Severe joint destruction in both brothers indicates a significant impact of abnormal lysosomal enzymes on cartilage integrity.
- Detailed analysis of the altered kinetic and physical properties of the deficient acidic alpha-mannosidase provides insights into enzyme dysfunction.
Implications:
- These findings expand the known spectrum of clinical manifestations and survival rates in mannosidosis.
- Understanding the mechanisms behind prolonged survival and severe joint involvement can inform future therapeutic strategies.
- Further research into lysosomal enzyme function in cartilage may lead to targeted treatments for joint degradation in mannosidosis and related disorders.