Background: Helminths induced eosinophilia is well known. Recent studies have been demonstrating that Giardia Lamblia is also able to cause eosinophilia and suggest that children with giardiasis have a higher risk of food allergy.
Case report: Newborn premature male patient, admitted to neonatology unit since birth, who presented persistent eosinophilia, associated with vomiting and abdominal distention when he ingested a not hydrolyzed milk formula. The subsequent study revealed milk allergy (grade II/III) but also of Giardia on stool. The child was treated with metronidazol with clinical improvement.
Conclusion: This case pretends to underline the importance of person-to-person transmission as far as Giardia infection is concerned and especially among young children. We also would like to emphasize a possible relation between giardiasis and food allergy, which has occasionally been described in recent literature.