Cystinosis is a rare genetic disorder caused by a mutation in the CTNS gene, which leads to the accumulation of the amino acid cystine within cells. This buildup primarily affects the kidneys, eyes, and other organs, resulting in various health issues. Symptoms often begin in childhood and can include kidney dysfunction, growth delays, and eye problems such as photophobia. Treatment for cystinosis typically involves the use of cystine-depleting agents, such as cysteamine, which help reduce cystine levels in the body. Early diagnosis and management are crucial to prevent severe complications, particularly kidney failure, and to improve the quality of life for affected individuals.