Eczema

[msbbc833]

Advertisement - Members don't see this ad

Hi yall,
FA 2010 says eczema is a type I hypersensitivity, but qbank just gave me a question that I got wrong which says it is a type IV. Whom do I trust?

 

[Step1Hash]

Hi yall,
FA 2010 says eczema is a type I hypersensitivity, but qbank just gave me a question that I got wrong which says it is a type IV. Whom do I trust?

I think its type I. Eczema = atopic dermatitis. And all atopy is type I.

 

[SDF1]

Its a type IV hypersensitivity.

Urticara and certain angioedemas are type 1.

 

[coralis]

eczema can be due to different causes, it's an all encompassing term, so it's variable. Your history is your best bet for getting those right.

If it came on in a few seconds following exposure --> Type 1
If it came on 24-48hrs later (ie: after exposure)--> Type 4

There are others that can be Type 3, such as an SLE rash.... so it depends!
And of course you can have your bullous ones that are type 2!!!!

 

[bruinhd]

eczema can be due to different causes, it's an all encompassing term, so it's variable. Your history is your best bet for getting those right.

If it came on in a few seconds --> Type 1
If it came on 24-48hrs later --> Type 4

There are others that can be Type 3, such as an SLE rash.... so it depends!
And of course you can have your bullous ones that are type 2!!!!

errrm...how can you tell if a case of eczema came on today or 48 hours ago...it comes on when it comes on...

 

[coralis]

errrm...how can you tell if a case of eczema came on today or 48 hours ago...it comes on when it comes on...

errrmmm... the patient tells you the rash appeared yesterday, and that he went camping 2 days ago...?! --> rash came on 24hrs after camping... type IV. Different from, rash appearing 2 minutes after I put latex gloves on. That sounds like a timeline to me. No?

 

[bruinhd]

errrmmm... the patient tells you the rash appeared yesterday, and that he went camping 2 days ago...?! --> rash came on 24hrs after camping... type IV. Different from, rash appearing 2 minutes after I put latex gloves on. That sounds like a timeline to me. No?

are you referring to campzema or poison oak/poison ivy (Type IV)?

 

[coralis]

are you referring to campzema or poison oak/poison ivy (Type IV)?

your question is the same like the OPs question!!!! And my point was to explain that eczema is an all encompassing term and can be ALL SORTS of hypersensitivity reactions depending on the patient's history.

Eczema is term for a group of medical conditions that cause the skin to become inflamed or irritated

 

[bruinhd]

your question is the same like the OPs question!!!! And my point was to explain that eczema is an all encompassing term and can be ALL SORTS of hypersensitivity reactions depending on the patient's history.

Eczema is term for a group of medical conditions that cause the skin to become inflamed or irritated

it's an all-encompassing term to the layperson/wikipedia.

In the medical world, "eczema" is usually referring to Dyshidrotic Eczema, a vesicular rash associated with atopy, classified under Type I hypersensitivity. It can be precipitated by episodes of Type IV hypersensitivity such as contact with nickel or other metals (which is where your 48 hr thing comes in to play).

So I would classify it as Type I hypersensitivity, with associations to Type IV. But I wouldn't throw an umbrella over all of the hypersensitivities for "eczema". A rash that is streaked or linear is likely Type IV hypersensitivity. A rash surrounding the belt buckle area or earrings, or necklace area is likely Type IV to nickel. A vesicular rash in the elbow creases is likely a Type I hypersensitivity (eczema).

If it's a vesicular, eczematous rash involving hypersensitive mast cell degranulation, then it's Type I hypersensitivity - regardless of whether it was triggered by seasonal allergies, playing basketball, or even a concomitant Type IV nickel/poison ivy exposure.

If it's a CD4/interferon mediated cell response, just nickel for example, then it is a Type IV hypersensitivity. Which can be a 48 hour response, but this is not always true. People who have had multiple exposures throughout their lives build up faster subsequent responses than 48 hours. It can happen the same day.

Sorry to troll you so hard. Figured I'd better explain myself instead of confusing the OP 😀

 

[coralis]

Lool.. I don't mind you trolling me but make it more complete sentences.
I agree with you that most commonly it's associated w/ Type 1 and 4 in the forms of atopic dermatitis and delayed type reactions to irritants. However there are tons other kinds.... ex: asteatotic eczema (winter dry skin), stasis dermatitis etc... many have unknown cause. The main issue I had with the OPs thinking is trying to classify eczema in his head as one thing only. And the truth is, in a clinical question they can say "eczema" to describe many things and try to throw you off, which will work if you classify eczema as only one thing 😉

Eczema is a clinical term that embraces a number of conditions with different underlying etiologies. All are characterized by red, papulovesicular, oozing, and crusted lesions at an early stage. The degree of these changes varies with clinical subtype. With persistence, these lesions develop into raised, scaling plaques. Clinical differences permit classification of eczematous dermatitis into: (1) allergic contact, (2) atopic, (3) drug-related eczematous, (4) photoeczematous, and (5) primary irritant forms. Most of these forms resolve completely when the offending stimulus is removed or exposure to it is limited, thus stressing the importance of investigating the underlying cause.

"Robbin's 8th Edition"