IGg and IGe

[Caden's Mom]

Can anyone explain to me what those mean? How do I know if DS's allergies are IGg or IGe or both?

[mhr1406]

I think that IgE is more so a histamine (hives, shock, breathing difficulty) reaction and IgG more likely to be annoyance type reactions like in the digestive tract.

[USAmma]

Here's some more:

IgE Mediated Allergies
Immediate onset (within minutes)
Circulating half life of 1-2 days
Permanent allergies
Stimulates histamine release
Includes foods, inhalants & molds


IgG Mediated Allergies
Delayed onset (4-72 hours)
Circulating half life of 21 days
Temporary allergies
Stimulates histamine release
Includes foods, herbs & spices

I just noticed IgG's might be temporary! Wow wouldn't that be great?!

[Crisstiana]

Hi, Heather:

IgG and IgE are different types of immunoglobuins (the "Ig" part), which is another way of saying they are different types of antibodies. They are a little different structurally and perform different functions.

IgE is involved in the immediate allergic responses that most people think of when they think of allergies. These include anaphylactic reactions to beestings or peanuts, and more moderate allergic reactions to pet dander or pollen. These are called Type 1 allergic responses and is the most common type of allergic responses. IgE binds to cells involved in allergies (mast cells and basophils). When two IgE molecules bind one piece of an allergen (e.g., part of peanut protein in peanut allergies), they cause these cells to dump histamine and other substances into the body. This stimulates nerves and causes pain and itching; increases mucous production and causes congestion; constricts the smaller airways and causes wheezing and coughing; makes the small blood vessels dilate and become more "leaky" and causes swelling and redness. In folks with allergies, the amount of IgE in the bloodstream can be thousands of times that of people without allergies.

IgG is often involved in autoimmune diseases and in blood group reactions and transplant rejection. It can work by a couple of mechanisms that result in destruction of cells inside the body. So IgG helps to "tag" cells inside the body that are identified as foreign by the body's immune system, and these tagged cells are then killed. This may include truly foreign cells, such as those in a transplanted organ that is being rejected, or by normal body cells that have bound an antigen and so look foreign to the body. Specific examples of these types of reactions (Type 2 allergic reactions) include rheumatic heart disease, multiple sclerosis, and some drug reactions.

So a major difference between IgE- and IgG-mediated allergic responses is histamine: In IgE reactions, the net effect is to release histamine immediately into the body. The effect of histamine (and other substances triggered by IgE) are all of the classic ones of "allergy": congestion, redness, swelling, coughing, hives, etc. When the reaction is especially severe, everything is worse (the coughing turns into wheezing and possible airway obstruction, the changes in the blood vessels causes shock, etc) and this is an anaphylactic reaction. An EpiPen works by overriding the effects of IgE and histamine on the system. In contrast, IgG does not result in the immediate release of histamine.

Another big difference is time of onset. IgE allergic responses can appear in a matter of seconds, while IgG-based responses usually takes hours to a day.

Hope that made some sense.

[Mrs. MAT]

This link has some info on the difference:
http://www.gdx.net/home/assessments/allergy/

My doctor explained that IgE tended to be permanent, immediate reactions. For example, peanut, shellfish etc. tend to be IgE. IgG tends to be more changeable; delayed onset, varies with time (can get better).

[Caden's Mom]

Can I just say dang? That means DS is IgE to strawberry and dairy and IgG to tomato and egg. I really want him to outgrow that dairy allergy!

Oh, and thanks for the explanations! I really appreciate the help.

[wendy1221]

There's still a chance of outgrowing IgE allergies, it's just not as likely if they haven't outgrown them by age 2. Even IgE allergies tend to be outgrown in kids under 2. I outgrew an IgE dairy allery when I was a kid. Dairy started making me really sick in college, which also when I was exposed to more b/c my mom never cooked w/ milk and cheese the way most people do, I guess, or at least the way the cafeterias do. It was all GI stuff, plus messed up sinuses, so I'm thinking it had turned into an IgG allergy. I SPT'd positive to it (and egg) but I RAST neg to both of them. After taking probiotics for a few years, and doing Liam's TED (top 8 free except fish) for a year, I am now able to handle cheese and yogurt if I don't do them every day. Milk might be ok, but it's too disgusting. I gag on one sip. I don't know how people can drink that stuff!

Even if the dairy allergy isn't outgrown, dairy allergy tends to be one that isn't as severe by the time you reach adulthood. Nuts, fish and shellfish are some of the only ones that tend to stay the same or get worse (sesame is another.) Most other allergies tend to get better, even if they aren't outgrown completely.

[cat19]

Here's some more:

IgE Mediated Allergies
Immediate onset (within minutes)
Circulating half life of 1-2 days
Permanent allergies
Stimulates histamine release
Includes foods, inhalants & molds

Okay--in general that may be true, but my son has IgE allergies and some of his reactions are not instant; for example, eczema is a fairly common allergic reaction--often an IgE reaction-and you may well not see it immediately.

[Crisstiana]

I don't know if this makes any difference, but there are two components to Type 1 allergic reactions: early phase, which may appear in seconds, and late phase, which appears hours later. Eczema is a nonspecifc term that encompasses a number of allergic skin conditions. Contact dermititis, commonly seen as a form of eczema, is often classified as Type 4 allergic reaction (delayed hypersensitivity). Type 4 reactions involve T-cells, not IgE, and symptoms may not appear for up to 3 days after exposure.

Does this matter to anyone? Probably not, but I thought I would add it to this interesting discussion.

- Microbiology and Immunology Online: HYPERSENSITIVITY REACTIONS
- FPNotebook: Hypersensitivity Reactions

[WC_hapamama]

If it makes anyone dealing with IgE food allergies feel any better, most of the allergies that my oldest son has outgrown, he's outgrown after age 5. He only outgrew one before age 3. He started out with 12+, and he's down to 5 (at age 9.5).

[wendy1221]

Right after I posted about outgrowing by 2, I checked my other allergy forums and someone had posted a link to reserch on outgrowing egg allergy. THey were tracking a large number of egg allergic kids and checking percentages outgrowing every few years. At age 16, a large percentage of kids were still outgrowing, so I guess there's always a chance!