Differential Diagnosis
- Retinoblastoma
- Toxocariasis
- Retinopathy of prematurity
- Coat’s disease
Diagnosis
The little boy’s ocular symptoms are caused by retinoblastoma, a tumor that arises from a mutation of the retinoblastoma tumor suppression gene.
Discussion
Retinoblastoma is the most common primary intraocular tumor in children, with an incidence of approximately 1 in every 15,000 live births. Approximately two-thirds of cases affect only one eye.
The tumor may be present at birth and is usually diagnosed by age 5. In the United States, the average age at presentation for a familial-inherited retinoblastoma is 14 months (24 months for sporadic nongermline retinoblastoma). The inherited form has no sex, race/ethnicity, or other predisposing factors, and it occurs equally in left and right eyes. Advanced paternal age has also been associated with the sporadic form of retinoblastoma.
Leukocoria (white pupillary reflex) is by far the most common presenting sign in patients with retinoblastoma. In the United States, leukocoria as the presenting sign accounts for nearly 60% of all cases of retinoblastoma. Strabismus is the second most common presenting sign, seen in 20% of retinoblastoma patients in the United States. Patients with atypical signs and symptoms including a red, painful eye with glaucoma, cloudy cornea, poor vision, floaters, vitreous hemorrhage, and signs of orbital inflammation tend to be diagnosed at a later age, with more advanced disease.
From an urgent care perspective, immediate referral to an ophthalmologist is warranted.
Acknowledgment: Image courtesy of Logical Images, Inc. (www.VisualDx.com/JUCM).