Lima beans are a type of legume eaten across the world; reports of lima bean allergy are relatively rare with limited information. Studies show that clinical reactions to lima bean typically correlate with cross-reactivity to several other legumes, including soya, peanut, black gram, and mesquite tree pollen.

Main

Lima beans are ingested as food across the world (2).

Other topics

There has also been a report of occupational asthma induced by exposure to boiled, minced and dried lima bean exposure (3)

Reports of lima bean allergy are relatively limited. Studies show that clinical reactions to one legume typically correlate with cross-reactivity to several other legumes. Based on this idea, mesquite tree pollen sensitized patients also showed cross-reactivity to lima bean (2).

In a study of patients with legume hypersensitivity in the USA, 87% had positive skin prick tests to peanut (60 of 69 patients), whereas 41% were positive to lima bean (13 of 32 patients). However, none of the patients had positive oral food challenges with lima bean (4). 

Asthma

Two studies have investigated sensitization to lima beans in asthmatic patients. In one study of 470 asthma and rhinitis patients in Delhi, India, 3.4% had positive skin prick tests (2). In another study of 216 bronchial asthmatic patients, 5–6% had positive skin prick tests to lima bean, defined as a wheal of ≥3 mm (5). 

Avoidance

Despite the potential for cross-reactivity, clinical hypersensitivity to one legume does not warrant dietary elimination of all legumes. Oral food challenges have shown clinically important cross-reactivity to legumes is rare, and due to the lack of clinical relevance, skin prick test results should not be used to determine prolonged food restriction diets (5)

Allergenic molecules

One report identified 23 potentially allergenic proteins isolated from lima beans (6). 

Cross-reactivity

Studies show that clinical reactions to one legume typically correlate with cross-reactivity to several other legumes such as soya, peanut, black gram (2). Studies have identified cross reactivity between lima bean and mesquite, including mesquite tree pollen.

In a study of 20 patients with a positive skin prick test to mesquite (Prosopis juliflora), none demonstrated skin-prick positivity to lima bean. However, 4 patients were positive for IgE to lima bean measured by enzyme-linked immunosorbent assay suggesting the presence of cross-reactive IgE. This study identified five shared protein allergens between mesquite and lima bean of various sizes: 20, 26, 35, 66 and 72 kDa (2). Another report confirmed cross-reactivity between mesquite tree pollen and lima bean (7).

A 35 kDa vicilin-like major allergen isolated from mesquite showed cross-reactivity to a number of legume proteins including lima bean (8).

Author: RubyDuke Communications

Reviewer: Dr. Michael Thorpe

Last reviewed:January 2022