Systemic allergic reaction and diarrhoea after pineapple ingestion.

Some foods may initiate allergic reactions. Anaphylaxis due to mangoes, oranges, nuts and other foods has been reported earlier. We report the clinical and laboratory features of 32 patients who became symptomatic shortly after they had eaten pineapples. Seventeen patients were males and 15 females with ages ranging from 5 to 70 years. Most of the patients complained of intense itching and urticarial rashes, followed by abdominal pain, vomiting and diarrhoea. Sixty-eight percent of the patients became symptomatic within half an hour of eating the pineapple. On examination 18 patients had an urticarial rash and a flushed face. Although none of the patients were severely dehydrated, 20 patients presented with shock. Their peripheral pulse and blood pressure were low or absent suggesting an anaphylactoid reaction. The median total eosinophil count was 1850 (250-6375/mm3). The serum IgE level measured in 4 patients was raised. The patients were treated with intravenous fluids and antihistamine. Some patients also received steroid and adrenaline. All patients recovered uneventfully. Our findings suggest that ingestion of pineapple may occasionally cause an anaphylactoid reaction.