A 4-year-old girl is brought to the office by her parents due to frequent squinting of the left eye. That eye also seems more prominent than the right, according to the mother. The child was born full term after a normal pregnancy and delivery. Developmental milestones have been age appropriate. Left eye examination reveals mild proptosis, esotropia, and optic disc pallor. Visual acuity is decreased in the left eye but is normal in the right. There are several large café-au-lait macules and marked axillary freckling. Which of the following is the most likely cause of this patient's ocular findings?

Question

A 4-year-old girl is brought to the office by her parents due to frequent squinting of the left eye.  That eye also seems more prominent than the right, according to the mother.  The child was born full term after a normal pregnancy and delivery.  Developmental milestones have been age appropriate.  Left eye examination reveals mild proptosis, esotropia, and optic disc pallor.  Visual acuity is decreased in the left eye but is normal in the right.  There are several large café-au-lait macules and marked axillary freckling.  Which of the following is the most likely cause of this patient's ocular findings?

Quizplus · Accepted Answer

11ec25c8_d701_d0c4_bc81_8fc2cbffb6a0_MD0003_00 This child with café-au-lait macules, axillary freckling, and monocular eye proptosis and vision changes likely has neurofibromatosis type 1 (NF1) with optic pathway glioma. café-au-lait macules NF1 is an autosomal dominant disease caused by a mutation to the NF1 gene, which codes for neurofibromin. Starting in childhood, patients usually develop characteristic skin and soft tissue findings, including café-au-lait macules, freckling in skinfolds, and Lisch nodules. Lisch nodules Approximately 15% of patients with NF1 who are age <6 also develop low-grade optic pathway glioma. These tumors are often asymptomatic but can grow large enough to compress the optic nerve and cause decreased visual acuity, alterations in color vision, optic nerve atrophy, and proptosis. (Choice A) Acoustic neuromas, or vestibular schwannomas, are benign tumors that arise from the eighth cranial nerve (CN VIII). They are seen in patients with neurofibromatosis type 2 and typically present with hearing loss and difficulty with balance. (Choice B) Craniopharyngioma is a rare tumor that usually arises in the pituitary stalk and typically affects children age 5-14. Manifestations arise from compression of the optic chiasm (eg, visual field defects) or pituitary stalk (eg, growth hormone deficiency). This tumor type is not associated with NF1 and is unlikely to cause proptosis. (Choice C) Medulloblastoma is a malignant pediatric brain tumor that typically results in increased intracranial pressure (eg, headache, nausea, vomiting) and cerebellar dysfunction (eg, gait ataxia, incoordination). Proptosis and esotropia would be uncommon; there is no association of medulloblastoma with NF1. (Choice E) Retinitis pigmentosa is an inherited degenerative disease of the retinal photoreceptor cells that causes bilateral tunnel vision and, eventually, binocular blindness. Uniocular vision loss, proptosis, and skin findings would be uncommon. (Choice F) Retinoblastoma is a rare intraocular malignancy that usually affects children age <2. Suspicion typically arises when a child has leukocoria, an abnormal white reflex of the eye. Patients may also have progressive deterioration of monocular vision, strabismus, and proptosis. This patient with café-au-lait spots and axillary freckling is more likely to have NF1 with an optic tract glioma. Retinoblastoma Educational objective: Neurofibromatosis type 1 is a genetic disorder that causes café-au-lait macules, freckling in skinfolds, Lisch nodules, and neurofibromas. Approximately 15% of children with this disorder develop optic pathway gliomas, which often manifest with unilateral vision loss, proptosis, esotropia, and optic disc pallor. References: Café-au-lait macules and neurofibromatosis type 1: a review of the literature. (http://www.ncbi.nlm.nih.gov/pubmed/27212418) Use of the National Institutes of Health criteria for diagnosis of neurofibromatosis 1 in children. (http://www.ncbi.nlm.nih.gov/pubmed/10699117)

A 4-Year-Old Girl Is Brought to the Office by Her