Lupin-induced anaphylaxis prevalence may be underestimated

Key takeaways:

• Almost 25% of patients had a coinciding peanut allergy.
• 66% of patients with lupin-induced anaphylaxis were female.

A recent study published in the European Journal of Allergy and Clinical Immunology shows that significant cross-reactivity may exist between lupin and other legumes.

Compared with other food allergens, lupin-induced anaphylaxis may present certain specificities, Guillaume Pouessel, MD, CH Roubaix, pediatrics department, Children’s Hospital, Roubaix, France, and colleagues wrote.

The true prevalence of lupin allergy is still unknown but because of increased consumption and cross-reactivity with peanuts, authors aimed to better understand it in comparison to other foods, the researchers continued.

Data were used from the Allergy-Vigilance Network between 2002 and 2020. Among the 2,708 instances of food-induced anaphylaxis, 62 (2.3%) were induced by lupin (mean age, 32.1 years; 35% in children; 66% in females).

A history of lupin allergy was found in nine (15%) patients. Four (6%) had a sensitization to lupin, whereas 22 (35%) had a known food allergy, 16 of which had a peanut allergy. Asthma history was found in 14 (23%) of patients and allergic rhinitis in 12 (19%).

Grade 2 anaphylaxis reactions were reported in 36 instances (58%), and grade 3 reactions were found in 26 cases (42%). Biphasic anaphylaxis reactions were seen in seven (11%) patients, and a cofactor was identified in 10 (16%). Also, 26 (42%) of the reactions occurred at home.

The most common foods responsible for the 62 cases of lupin-induced anaphylaxis included prepackaged food products (95%), of which 47 (76%) involved pastries, biscuits and breads.

Children aged younger than 18 years that experienced lupin-induced anaphylaxis were predominantly male (P < .001) and had a history of asthma (P = .003) and peanut allergy (P < .001) when compared with adults.

When comparing lupin-induced anaphylaxis with other foods, the reaction was seen more often in females (P = .003), in adults (P = .004), in those with a peanut allergy (P < .001) and after consumption of prepackaged foods (P < .001).

In the same comparison, the frequency of hypotension (P = .001), laryngeal oedema (P = .048), bronchospasm (P < .001), and a biphasic reaction (P < .001) were higher in those with lupin-induced anaphylaxis.

Researchers noted that lupin was linked to approximately 2.3% of anaphylaxis cases in France over the last two decades. Additionally, the frequency of lupin’s involvement in anaphylactic reactions was stable at around 1.2% to 1.4% in France in the last decade. In Europe, it is reported in around 0.8% of cases within the same timeframe, which researchers say might be evidence of an underestimation of the allergy.

Authors also emphasized that a quarter of the patients included in this study had a history of peanut allergy, whereas 8% had a history of other legume allergies, which could reveal significant cross-reactivity with lupin.