Toxocariasis mimicking liver, lung, and spinal cord metastases from retinoblastoma

Area of Science:

• Ophthalmology
• Infectious Diseases
• Pediatric Oncology

Background:

• A boy with bilateral retinoblastoma, characterized by extensive choroid and optic nerve invasion, underwent metastatic surveillance.
• The patient had an increased risk for systemic and central nervous system metastasis due to the advanced nature of the retinoblastoma.

Observation:

• Two years post-chemotherapy, surveillance MRI revealed new lesions in the liver, lungs, and spinal cord.
• Laboratory results indicated high Toxocara antibody titers, marked eosinophilia, and elevated immunoglobulin E (IgE) levels.

Findings:

• The clinical presentation and laboratory findings supported a diagnosis of toxocariasis, a parasitic infection, rather than retinoblastoma metastasis.
• This case represents the first reported instance of early, asymptomatic spinal cord toxocariasis detected incidentally during oncologic surveillance.

Implications:

• This finding highlights the importance of considering parasitic infections in patients with a history of cancer, especially when metastasis is suspected.
• Incidental diagnosis through metastatic surveillance underscores the need for comprehensive differential diagnoses in pediatric oncology patients.
• Early detection of spinal cord toxocariasis can prevent potential neurological complications and guide appropriate treatment.