Delayed Onset
(IgG-Mediated)
|
Immediate Onset
(IgE-Mediated)
|
| Multiple foods can be involved |
Rarely more than 1-2 foods
involved. |
| Large amount of the food needed
to provoke symptoms; reactions may not occur after single food challenge. |
Even trace amounts of food
can trigger severe life threatening reactions. |
| Reactions occur 2-24 hours
after eating reactive foods; rarely up to 72 hours have reactions been
reported. |
Reactions occur 2 hours or
less after consumption of offending foods. |
| Any organ system can be involved
in reaction including the classic allergic areas. |
Primarily affects: Skin, airway,
and digestive system. Classic processes: hives, asthma, eczema, vomiting,
diarrhea, and anaphylaxis. |
| Very common (children, and
adults) Over 50 medical problems caused, provoked or worsened by food
sensitivities. |
Rare in adults. |
| Addictive cravings and withdrawal
seen in 20-30%. |
Addictive cravings never seen. |
| Because multiple foods and
delayed onset of symptoms, the offending foods rarely self-diagnosed. |
Offending food is often diagnosed
because of immediate reaction. |
| Allergic foods are favorite
foods. |
Allergic food is a rarely
eaten food. |
| Symptoms clear after avoidance
for 6 months. |
A permanent fixed allergy. |
| IgE RAST negative; IgG positive
(type II) often. |
IgE and skin test positive
(type I) reaction. |
| IgG food immune complexes (type
E) and cellular (type IV) reactions common. |
IgG not involved. |
| Sensitized lymphocytes, eosinophils,
platelets, release of leukotrienes prevalent. |
Mast cell release of histamine
and tryptase involved. |
