Congenital cataract is a severe ocular disease that should be detected as early as possible to ensure prompt management and the prevention of blindness. Etiologies include genetic mutations, chromosomal abnormalities, metabolic disorders, and intrauterine infections. Congenital cataract is identified on the red reflex screening in the newborn exam.
Congenital cataract, defined as opacification of the lens, is a significant eye disease that may result in childhood blindness if not treated early and promptly . The leading cause of this condition is a genetic mutation which accounts for 25% of cases and is transmitted in an autosomal dominant pattern . Congenital cataract can appear as part of trisomies 21 and 18 or metabolic disorders such as galactosemia, Wilson's disease, hypocalcemia, etc  . This eye disease may also develop as a result of a congenital infection syndrome. Diseases such toxoplasmosis, rubella, cytomegalovirus (CMV), and herpes simplex infections (known as the TORCH) could cause damage to the eyes, brain, limbs, and possible death  . Other intrauterine infectious causes include Treponema pallidum and varicella zoster virus (VZV) . It is of utmost importance to detect this disease at birth in order to ensure prompt referral to ophthalmology and adequate treatment for prevention of blindness.
The clinical presentation in neonates includes the absence of a red reflex . Additionally, these infants exhibit nystagmus, unawareness of their surroundings and fail to fix and follow . Note that cataract may affect one or both eyes.
Screening for congenital cataracts is performed easily with the red reflex examination, which is highly recommended for all newborns  . This test also assesses for other ocular pathologies as well .
During the newborn ocular screen, white reflex (also called leukocoria) is indicative of cataracts . This is followed by further types of examination such as the slit lamp and dilated fundus.
Exam findings in patients with metabolic or systemic diseases will reflect related clinical syndromes.
Neonates exhibiting an abnormal red reflex warrant a prompt workup and consultation with an ophthalmologist. During the assessment, the medical team should elicit the maternal history which includes diet, exposure to pets, lifestyle, and living environment . Also very important is a thorough newborn physical exam including a hearing test. Moreover, the evaluation will include pertinent studies.
Infectious causes should be investigated with TORCH titers and the Venereal Disease Research Laboratory (VDRL) test. Additionally, the workup may include a complete blood count (CBC) and urine studies measuring calcium, amino acids, phosphorous, etc.
Finally, another component of the workup includes genetic testing .
Brain computed tomography (CT) may also be indicated.