Cataracts in childrens

A cataract means any opacity of the lens.Cataract is not the common problem in pediatric practice, but it is the most common cause of treatable childhood blindness. Some are detected incidentally on clinical examination, majority are observed by the parents or caretakers & others may present with visual complaints. Cataracts are more common in low birth weight infants (< 2500 g). The differential diagnosis of cataracts in infants & children includes a wide range of causes like developmental disorders, congenital infections, inflammatory disorders, metabolic diseases and toxic and traumatic insults. Cataracts may also develop secondary to intraocular diseases, such as retinopathy of prematurity, retinal detachment, retinitis pigmentosa, uveitis etc. Inherited & syndromic conditions also have cataracts, besides other features. Prematurity: A special type of lens changes are seen in preterm babies, called a cataract of prematurity. The cluster of tiny vacuoles in the distribution of the ‘Y’ sutures of the lens are seen in these infants. They can be visualized with an ophthalmic examination, but best seen with the well dilated pupil. The exact reason is not known, but the opacities disappear within few week by its own. Developmental Variants Early developmental process may lead to various congenital lens opacities. Discrete dots or white plaque like opacities of the lens capsule are common & sometimes involve the contiguous sub capsular region. Congenital Infections Cataracts in infants & children can be due to congenital infections like rubella, toxoplasmosis, cytomegalovirus, herpes simplex virus etc. Metabolic disorders Cataracts are a prominent manifestations of many metabolic disorders. Galactosemia is the most common cause of cataract amongst metabolic disorders. In classic infantile galactosemia, galactose – I- phosphate uridyl transferase deficiency, the cataract is typically of zonular type. Persistent jaundice, hepatomegaly, hypoglycemia, seizures & cataract in an infant are classical features of galactosemia. With early treatment (galactose free diet) the lens changes may be reversible. In galactokinase deficiency, cataracts are the sole clinical manifestation. In children, with juvenile onset diabetes mellitus, lens examination at certain intervals is mandatory. Some develop snowflake like white opacities & vacuoles of the lens. Others develop cataracts that may progress & mature rapidly, sometimes in a matter of days, especially during adolescence. Congenital lens opacities may be seen in children of diabetic & pre diabetic mothers. Hypoglycemia in neonates can also be associated with early development of cataracts. Ketotic hypoglycemia is also associated with cataracts. An association between cataracts & hypocalcemia is known. Various lens opacities may be seen in patients with hypoparathyroidism. Oculocerebrorenal syndrome (Lowe syndrome) is associated with cataracts in infants. Sunflower cataract is known to occur in Wilson disease, but is not commonly seen. Mucopolysaccharidoses, Niemann - Pick disease & Fabry disease are other metabolic conditions associated with cataracts. · Inherited diseases Many cataracts unassociated with other diseases are hereditary. The most common mode of inheritance is autosomal dominant. Autosomal recessive inheritance occurs less frequently. It is sometimes found in community with high rates of consanguinity. X – linked inheritance of cataracts unassociated with other diseases is relatively rare. · Chromosomal defects Lens opacities of different types may occur in association with chromosomal disorders like Down Syndrome (Trisomy 21), Edward syndrome (Trisomy 18), Patau syndrome (Trisomy 13), Turner syndrome (45,X), Noonan syndrome, various deletion & duplication syndromes. · Trauma Trauma to the eye is a significant cause of cataracts in children. It may result from blunt or penetrating injuries. Cataracts can be an important manifestation of child abuse. · Radiation Cataract formation after exposure to therapeutic radiation is dose & duration dependent. · Drugs & Toxins Of the various drugs & toxic substances that may cause cataracts, steroids are of major importance in children. Steroid related cataracts are posterior capsular type. Steroids induced cataracts may be reversible in some cases. All children receiving long term steroid treatment should have periodic eye examination. · Miscellaneous Several multisystem diseases & eye anomalies are known to manifest with cataracts. ·Idiopathic

Many a times, clinician may not get a cause of cataracts in children in spite of good evaluation. Common causes of cataracts · Congenital infections × Rubella. × Cytomegalovirus. × Toxoplasmosis. × Herpes Simplex Infection × Syphilis · Developmental variants × Prematurity × Low birth weight babies · Metabolic disorders × Galactosemia. × Homocystinuria. × Wilson disease. × Fabry disease. × Abetalipoproteinemia. × Niemann - Pick disease. × Refsum disease. × Mucopolysaccharidosis. · Chromosomal Disorders × Down syndrome (Trisomy 21). × Edward syndrome (Trisomy 18). × Patau syndrome (Trisomy 13). × Turner syndrome (45, XO). × Noonan syndrome. · Multisystem Genetic Disorders × Cockayne disease × Marfan syndrome. × Apert syndrome. × Crouzon disease. × Ectodermal dysplasia. × Lowe syndrome (Cerebrooculorenal syndrome). × Laurance Moon Biedel Syndrome × Nail - patella syndrome. × Prader - Willi syndrome. · Endocrinal Disorders × Diabetes Mellitus × Hypoparathyroidism. × Hypoglycemia. · Ocular anomalies × Retinitis pigmentosa × Coloboma. × Retinoblastoma. · Miscellaneous × Trauma. × Radiation. × Juvenile Idiopathic arthritis. × Toxins × Drugs (Cortiosteroids)