Baylisascariasis Overview
Clinical Presentation
The larvae of B. procyonis are capable of invading the human spinal cord, brain, and eyes. Non-specific signs and symptoms including nausea, fever and lethargy may appear as soon as one week post infection. The clinical presentation of baylisascariasis depends on the number and location of larvae in the body.
- Neural larva migrans often presents as acute eosinophilic meningoencephalitis. Symptoms can include weakness, lack of coordination, ataxia, irritability, seizures, altered mental status, stupor, and/or coma.
- Ocular larva migrans may present as diffuse unilateral subacute neuroretinitis, photophobia, retinitis, and/or blindless.
- Visceral larva migrans can present with macular rash, abdominal pain, hepatomegaly, and pneumonitis.
Younger children as well as persons with developmental disabilities or pica are at higher risk for B. procyonis infection as they may be more likely to put contaminated objects (fingers, soil, sand, etc.) into their mouths. However, anyone can be infected if they accidentally consume infective eggs in soil, water, or objects contaminated with raccoon feces.
Diagnosis
The diagnosis of baylisascariasis can be challenging. Clinical diagnosis includes eosinophilic pleocytosis, peripheral eosinophilia, and deep white matter abnormalities on MRI. Larva or larval tracks or lesions may be visible during ocular examinations.
There is no commercially available test for B. procyonis. Serological testing of serum and CSF for anti-Baylisascaris antibody titers can be performed at the U.S Centers for Disease Control and Prevention (CDC). Testing for other parasitic infections such as Toxocara spp. and Angiostrongolis spp. should also be considered.
Upon suspicion of baylisascariasis, clinicians should immediately contact LAC DPH Acute Communicable Disease Control (ACDC) who will approve testing, if indicated, and will provide instructions for the testing of serum and CSF by the CDC. Once approved for testing, specimens should be submitted to LAC DPH PHL for processing and transport to CDC.
Treatment
No drug has been found to be completely effective against baylisascariasis. Early treatment with albendazole, a broad spectrum anthelmintic, may reduce serious damage caused by the infection. Treatment should be initiated as soon as possible after ingestion of infectious material, ideally within three days.
If baylisascariasis is suspected, immediate treatment with 25-50 mg/kg albendazole daily for 10-20 days is recommended. If albendazole is not immediately available, mebendazole or ivermectin may be used in the interim.
Concurrent corticosteroids treatment to help reduce the inflammatory reaction is indicated to attempt to control of the disease.
Prevention
