Anaphylaxis following the ingestion of flour contaminated by house dust mites--a report of two cases from Singapore.

This study presents two patients who developed anaphylaxis after eating mite-contaminated food, and also contains a survey of dust-mites contamination in flour samples from Singapore households. The clinical records of each patient was studied. Patient A developed anaphylaxis twenty minutes following the ingestion of home-made fried fish coated with Japanese flour, while Patient B developed similar life-threatening symptoms one hour after the ingestion of home baked scones. Both patients were NSAID-intolerant and had a history of allergic rhinitis. Skin prick tests showed a strong positive result for dust-mites and for extracts prepared from the ingested flour. Flour samples were also examined microscopically which revealed large numbers of live Dermatophagoides farinae dust-mites. A survey of 57 flour samples showed that 4 samples (7%) were contaminated with dust mites. The findings in the present study confirm that mite-contamination of flour exists in Singaporean households, and it may trigger anaphylaxis in susceptible individuals.