What causes cataracts in young individuals?

Causes of Cataracts in Young Individuals

Cataracts in young individuals are primarily caused by congenital factors, genetic mutations, systemic diseases (especially diabetes), medications (particularly corticosteroids), trauma, and environmental exposures. 1, 2

Congenital and Genetic Causes

• Hereditary or genetic predisposition is a significant factor in early-onset cataracts, with specific mutations affecting lens proteins, particularly crystallins, connexins, and membrane proteins 3
• Congenital cataracts can result from genetic mutations that severely damage lens proteins, disrupting lens microarchitecture and transparency 3
• Chromosomal abnormalities such as Down syndrome are associated with increased risk of cataract formation in young individuals 2
• Family history of congenital or genetic ocular anomalies significantly increases risk of early cataract development 4

Systemic Medical Conditions

• Diabetes mellitus is strongly associated with increased risk of cataract formation in young individuals through multiple mechanisms including sorbitol accumulation and increased oxidative stress 1, 5
• Type 1 diabetes can cause cataracts in children and adolescents, with cataracts sometimes appearing before, during, or after diabetes diagnosis 5
• Metabolic syndrome components (diabetes, hypertension, obesity, and dyslipidemia) significantly increase cataract risk even in younger populations 1
• Congenital infections such as rubella can cause cataracts in infants 2
• Certain genetic syndromes with ocular involvement predispose to early cataract formation 4

Medication-Related Causes

• Long-term use of inhaled or oral corticosteroids significantly increases risk of cataract formation, particularly posterior subcapsular cataracts, which can affect individuals of any age 1
• Phenothiazines are associated with anterior subcapsular opacities that can develop in younger patients 1
• Both systemic and topical steroids are significant risk factors for posterior subcapsular cataract formation in young individuals 6

Trauma and Environmental Exposures

• Ocular trauma, both blunt and penetrating, significantly increases risk of cataract formation regardless of age 1
• Ultraviolet-B radiation exposure is strongly associated with lens opacities, especially cortical cataracts, with cumulative exposure being important even in younger individuals 1, 6
• Ionizing radiation is a proven cause of cataracts, with risk present even at relatively low exposures 1
• Exposure to radiation therapy for cancer treatment can induce cataract formation in children 2

Visual Deprivation

• Visual deprivation amblyopia can be caused by complete or partial obstruction of the visual axis, resulting in a degraded retinal image, with congenital or early-onset cataract being a common cause 4
• Dense central cataracts are likely to cause amblyopia in young children, affecting visual development 4
• Polar cataracts and lamellar cataracts may cause mild to moderate amblyopia or have no effect on visual development 4

Clinical Presentation and Management

• Young patients with cataracts may experience decreased visual acuity, visual glare, and reduced contrast sensitivity 7
• Different types of cataracts affect vision differently - nuclear cataracts primarily affect distance vision, while posterior subcapsular cataracts cause glare and affect near vision more 8
• Early diagnosis and treatment are crucial for preventing amblyopia and ensuring proper visual development in children 4
• Children with known or suspected cataracts should be referred to a pediatric ophthalmologist 4

Prevention Strategies

• UV protection, such as wearing brimmed hats and UV-B blocking sunglasses, can reduce risk of cataract development 1
• Safety glasses are recommended for high-risk recreational or work activities to prevent traumatic cataracts 1
• Management of systemic diseases, such as diabetes, is important for reducing cataract risk in susceptible individuals 1, 5
• Monitoring patients on long-term corticosteroids and considering alternative treatments when possible may reduce cataract risk 1