As the disease continues to progress through the adolescent years, other signs and symptoms may become apparent:

• Intellectual disability will progressively worsen
• Sleep disturbance
• Anxiety, restlessness, and inability to understand the concept of time
• Emotional, behavioral, and psychiatric issues can arise
• Dental complications such as tooth decay, large tongue, and enlarged tonsils
• Progressive thickening of facial features: widely-spaced eyes, small ears, full lips, large tongue, broad nose
• Gastrointestinal symptoms including diarrhea or constipation
• Gait (walking) disturbance