Pica and Parasites

Abstract & Commentary

Synopsis: Exposure to and possible ingestion of soil contaminated by raccoon feces was associated with eosinophilic meningitis and severe neurologic consequences in 2 children.

Source: Raccoon roundworm encephalitis—Chicago, Illinois, and Los Angeles, California, 2000. MMWR Morb Mortal Wkly Rep. 2002;50:1153-1155.

A 2-year-old boy with iron deficiency anemia and pica was noted to have dirt on his mouth while playing in a suburban Chicago park. Two and a half weeks later, he developed low-grade fever, lethargy, and ataxia with eosinophilia in his blood (28% of 21,000 white cells per mm³) and cerebrospinal fluid (CSF, 32% of 80 white cells per mm³). Blood and CSF antibody testing were positive for antibodies to Baylisascaris procyonis as was subsequent soil testing for ova in the park where the child had played. The child survived but has profound neurologic compromise and requires continuous nursing care.

A 17-year-old boy with developmental disabilities and geophagia regularly played in a yard at his group home for handicapped adolescents. He became comatose following 2 days of low-grade fever and incoordination. Eosinophilia was noted in peripheral blood (15% of 15,900 white cells per mm³) and spinal fluid (37% of 19 white cells per mm³). Brain biopsy, blood serology, and CSF antibody testing, as well as analysis of sand box soil in the yard where the boy had played, were all positive for B procyonis. The boy remained comatose for a year and then died.

Comment by Philip R. Fischer, MD, DTM&H

B procyonis is a roundworm that infects more than two thirds of raccoons in many parts of the United States.¹ Eggs in raccoon feces become infective 2-4 weeks after defecation and can remain viable for years. Infection in a variety of birds and mammals (including pet rabbits² and humans) occurs with ingestion of parasite egg-contaminated soil; for humans, this is a particular problem in children with pica. In the gastrointestinal tract, larvae emerge from the eggs and migrate to cause neural larva migrans or, less commonly, ocular or visceral larva migrans.

Pica (geophagia), as noted by the 2 cases reported in Morbidity and Mortality Weekly Report, usually occurs in children with iron deficiency anemia or neurodevelopmental compromise. Especially when it involves pet feces, pica is socially bothersome and can facilitate the transmission of diseases such as toxocariasis³ and toxoplasmosis.⁴ Pica has also been linked to intestinal parasite infections in children in Jamaica,⁵ Kenya,⁶ and Guinea.⁷

CSF pleocytosis with eosinophilia is uncommon. Eosinophilic meningitis can be found with some tumors and following some surgical procedures. Usually, however, eosinophilic meningitis is due to infection with Angiostrongylus cantonensis, a parasite obtained by eating raw snails. This is reported from areas bordering the Pacific Ocean⁸ as well as in travelers to the Caribbean and elsewhere.^9,10

Each of the children reported recently in the Morbidity and Mortality Weekly Report failed to respond noticeably to albendazole. Once larva migrans is established, there is no proven therapy for B procyonis infection. Due to the possibility of extremely poor outcomes with this infection, however, presumptive therapy with albendazole (25-50 mg/kg/d for 10 days) could be considered for any child who was noted to eat soil that might have been contaminated by B procyonis eggs.

Clearly, one need not leave urban America to get “exotic” parasitic infections. Pica, when noted, should prompt medical evaluation to ensure that no treatable iron deficiency goes unrecognized. Travelers, like children playing in American parks, need to be particularly cautious about washing their hands before eating. B procyonis eggs can be widespread in residential communities,¹¹ and environmental interventions will be important in the control of this infection.

References

1. Kerr CL, et al. Baylisascariasis in raccoons from southern coastal Texas. J Wildl Dis. 1997;33:653-655.

2. Deeb BJ, DiGiacomo RF. Cerebral larva migrans by Baylisascaris sp in pet rabbits. J Am Vet Med Assoc. 1994;205:1744-1747.

3. American Academy of Pediatrics. 2000 Red Book: Report of the Committee on Infectious Diseases. Elk Grove Village, Ill: American Academy of Pediatrics; 2000:582-583.

4. MacKnight KT, Robinson HW. Epidemiologic studies on human and feline toxoplasmosis. J Hyg Epidemiol Microbiol Immunol. 1992;36:37-47.

5. Robinson BA, et al. Childhood pica. Some aspects of the clinical profile in Manchester, Jamaica. West Indian Med J. 1990;39:20-26.

6. Geissler PW, et al. Geophagy as a risk factor for geohelminth infections: A longitudinal study of Kenyan primary schoolchildren. Trans R Soc Trop Med Hyg. 1998;92:7-11.

7. Glickman LT, et al. Nematode intestinal parasites of children in rural Guinea, Africa: Prevalence and relationship to geophagia. Int J Epidemiol. 1999;28:169-174.

8. Tsai HC, et al. Eosinophilic meningitis caused by Angiostrongylus cantonensis: Report of 17 cases. Am J Med. 2001;111:109-114.

9. Fischer PR. Eosinophilic meningitis. West J Med. 1983;139:372-373.

10. Re VL, Gluckman SJ. Eosinophilic meningitis due to Angiostrongylus cantonensis in a returned traveler: Case report and review of the literature. Clin Infect Dis. 2001;33:e112-115.

11. Park SY, et al. Raccoon roundworm (Baylisascaris procyonis) encephalitis: Case report and field investigation. Pediatrics. 2000;106:e56.

Published: February 2002