An analysis has been presented of the clinical features of visceral larva migrans based on the study of 20 cases seen during a 10-year period at the Ochsner Clinic. The disease is seen in small children who eat dirt and who thus ingest the ova of the canine roundworm, Toxocara canis. Larvae of the parasite invade the liver, causing hepatomegaly with extreme eosinophilia, and usually fever and anemia. Migration of the larvae to other organs may result in pneumonitis, encephalitis or myocarditis. Lesions may also be seen in skin, kidneys and possibly in bone. Proof of diagnosis requires biopsy of liver or other infected tissue. Treatment with diethylcarbamazine (Hetrazan) may be helpful, but even without treatment, once pica is stopped most patients recover. Serious sequelae are seen in the form of intraocular granulomata, sometimes causing blindness. These lesions, because they resemble retinoblastoma, have in the past led to unnecessary enucleation of the eye. Enucleation for suspected retinoblastoma, therefore, should not be performed without due consideration of the possibility of a benign granuloma caused by T. canis.