Individuals with<unk>  typically have normal development in infancy. Around the age of 2–4 years, they begin showing signs of developmental delay, but development is still progressing. Initial symptoms may present as clumsiness and/or speech delay. Individuals with<unk>  also show increased upper respiratory infections. Development continues until about puberty; however, an individual at 13–16 years of age typically shows mental and motor development similar to a 5-6 year old. Around puberty, a gradual decline in mental abilities and motor skills occurs. This progressive decline continues until about age 25–28, when rapid impairment of abilities occurs, resulting in severe intellectual disability.
Aspartylglucosaminuria
Hawkinsinuria
Alkaptonuria
Essential fructosuria
Orotic aciduria
Cystathioninuria
Dicarboxylic aminoaciduria
Urocanic aciduria