Summary about Disease
Aspartylglucosaminuria (AGU) is a rare, inherited lysosomal storage disorder caused by a deficiency of the enzyme aspartylglucosaminidase (AGA). This enzyme is responsible for breaking down certain glycoproteins. Due to the deficiency, these glycoproteins accumulate in lysosomes throughout the body, leading to various developmental, neurological, and skeletal abnormalities.
Symptoms
Symptoms of AGU vary in severity and onset but commonly include:
Infancy: Hypotonia (floppy baby syndrome), recurrent respiratory infections, diarrhea, umbilical hernia.
Early Childhood: Delayed speech development, intellectual disability, coarse facial features, skeletal abnormalities (thickened skull, scoliosis), behavioral problems (hyperactivity, aggression).
Later Childhood/Adolescence: Progressive intellectual decline, seizures, ataxia (lack of coordination), joint stiffness, heart valve problems, and skin lesions (angiokeratoma).
Causes
AGU is caused by mutations in the AGA gene. This gene provides instructions for making the aspartylglucosaminidase enzyme. The disease is inherited in an autosomal recessive pattern, meaning that both parents must carry a copy of the mutated gene for a child to be affected.
Medicine Used
4. Medicine used There is currently no cure for AGU. Treatment focuses on managing the symptoms and improving the quality of life.
Enzyme Replacement Therapy (ERT): Currently, enzyme replacement therapy is under research and is not yet available in the market.
Symptomatic Management: Medications may be used to control seizures, manage behavioral problems, and treat infections. Physical therapy and occupational therapy can help with motor skills and coordination.
Bone Marrow Transplantation: In some cases, hematopoietic stem cell transplantation (HSCT) (bone marrow transplant) has been considered, however, the results are not very successful and the complications are high.
Is Communicable
No, AGU is not communicable. It is a genetic disorder and cannot be spread from person to person.
Precautions
There are no specific precautions to prevent AGU, as it is a genetic disorder. Genetic counseling is recommended for families with a history of AGU to assess the risk of having an affected child.
How long does an outbreak last?
AGU is not an infectious disease and does not involve outbreaks. It is a chronic, progressive condition.
How is it diagnosed?
Diagnosis of AGU typically involves:
Clinical Evaluation: Assessment of symptoms and physical examination.
Urine Analysis: Detection of elevated levels of aspartylglucosamine in urine.
Enzyme Assay: Measurement of aspartylglucosaminidase enzyme activity in leukocytes (white blood cells) or fibroblasts.
Genetic Testing: Confirmation of the diagnosis by identifying mutations in the AGA gene.
Timeline of Symptoms
9. Timeline of symptoms
Infancy (0-12 months): Hypotonia, recurrent respiratory infections, diarrhea, umbilical hernia.
Early Childhood (1-5 years): Delayed speech development, intellectual disability, coarse facial features, skeletal abnormalities, behavioral problems.
Childhood (6-12 years): Progressive intellectual decline, seizures, ataxia, joint stiffness.
Adolescence/Adulthood (13+ years): Continued intellectual decline, heart valve problems, skin lesions. The severity and progression of symptoms vary between individuals.
Important Considerations
Early Diagnosis: Early diagnosis and intervention are crucial for maximizing the individual's potential and quality of life.
Multidisciplinary Care: Management of AGU requires a multidisciplinary team of specialists, including geneticists, neurologists, pediatricians, physical therapists, and occupational therapists.
Genetic Counseling: Genetic counseling is essential for families affected by AGU to understand the inheritance pattern and recurrence risk.
Support Groups: Connecting with support groups can provide emotional support and valuable information for families and individuals affected by AGU.