Discussion
Sensitisation to food antigens has been thought to occur through multiples routes including cutaneous, respiratory tract, and via the gastrointestinal tract through direct exposure or in breast milk. In this case, prior exposure to banana through the oral route has not been reported; however, sensitisation may have been established via other routes. Given that the patient has eczema and that impairment in skin barrier and exposure through the cutaneous route has been implicated in the pathogenesis of other food allergies, this might have contributed to prior sensitisation. Other possibilities include inadvertent oral exposure, or exposure through breast milk. Given that some of the major banana allergens may be heat sensitive it is possible that exposure to fresh banana may have contributed to the severity of his symptoms.