Cataracts are most often found in the elderly (age-related cataracts); however, some unfortunate babies have a type of cataract present at birth or shortly afterwards – these are known as congenital cataracts.
Children sometimes may develop cataracts, known variously as infantile, juvenile or developmental cataracts.
Finding cataracts in babies and children is rare. It is thought to affect 3 or 4 children per 10,000 born in the UK.
Some congenital cataracts only involve a small part of the lens of the eye and do not affect vision sufficiently to require surgery.
Some congenital cataracts, though, depending on their location within the lens or how opaque they are, will cause vision problems and require congenital cataract surgery to remove cataracts from the child’s eye.
Cataracts may also be diagnosed later on, e.g. in an older baby and child. Here they may be known as infantile cataracts or paediatric cataracts.
In older children, trauma such as a strike to the child’s eye has been found to be the underlying reason in four out of every ten cases of cataracts.
It is also important to remember that some childhood cataracts may actually have been present at birth and be true congenital cataracts that were not initially seen and only found during the child’s first eye test with an ophthalmologist.
Congenital cataracts and amblyopia (lazy eye)
Cataract surgery is performed in infancy to allow the baby’s eye to develop normal vision and avoid a condition called amblyopia, or lazy eye.
Amblyopia is when the visual part of the brain (at the back of the brain in the occipital cortex) fails to develop sufficient ‘processing power’.
The occipital part of the brain needs a clear image to develop the best ‘computing’ ability in early life to process and perceive images in high detail.
If this high-level wiring isn’t developed because the incoming image is blurry, vision can be left permanently poor or result in blindness.
Causes of a congenital cataract
Congenital cataracts can be found in newborns for a variety of reasons, including:
- Genetic traits
- Disorders of metabolism
- Maternal infections
- Maternal factors – e.g. malnutrition, alcohol abuse
- Reaction to medications – e.g. tetracycline, steroids
- Traumatic injury – particularly older children
Congenital cataracts can be inherited from the parents; in fact, one in three cataracts in babies are inherited.
Cataracts can occur in isolation or may be part of a more widespread abnormality in the eye, e.g. including failure to develop the iris, a small front portion of the eye or retinal problems.
Congenital cataracts can also occur with other abnormalities in the body, e.g. chromosomal irregularities, Lowe syndrome (cataracts plus kidney and brain problems) or neurofibromatosis.
Maternal and fetal factors linked to cataracts
Drug use in pregnancy can cause congenital cataracts. For example, the usage of tetracycline (a common antibiotic), when used to treat infections in pregnant women, has been shown to lead to the formation of cataracts in the newborn.
Congenital cataracts can arise if the mother acquires an infection during pregnancy. Some of the most common infections leading to cataracts are:1
- Measles (rubeola) or German measles (rubella) – most frequent cause of congenital cataracts
- Herpes (simplex or zoster)
- CMV (cytomegalovirus)
- Epstein-Barr virus
1Khurana AK. 4th ed. New Delhi: New Age International (P) Ltd; 2007. Diseases of the lens, Comprehensive Ophthalmology; pp. 167–204.