This coincides with the approximate time frame for Type IV hypersensitivity
IgE or IgG antibodies from a sensitised patient will bind appropriate allergens in the membrane (30), (31) Nasal challenge test Performed to identify the causative agent in patients with suspected rhinitis (22) Lung function test Breathing test that measures the quantity and speed of exhaled air Exhaled nitric oxide Employed in diagnosing asthma, monitoring response to therapy, evaluating current symptom control, and predicting exacerbations of asthma (32) Patch test Suspected allergens placed on patient's back induce a type IV hypersensitivity
reaction via specific T lymphocytes which is read after 72 hours to determine allergic reaction (8)
A positive reaction, indicating type IV hypersensitivity
, is defined as a SI greater than 3 and an equivocal reaction is a SI between 2 and 3.
The long duration of skin contact and the high concentration of PPD (up to 16%) dramatically increase the risk of contact dermatitis, Reactions are typically type IV hypersensitivity
presenting as pustular dermatitis, eczemarous and vesicular dermatitis, lichenoid reaction, or generalized dermatitis.
The most common are the Type I and Type IV hypersensitivity
Skin Reactions to Latex Reaction Response Irritation Contact Dermatitis red, chapped hands (rapid--minutes to hours) blistering burning or itching dry skin reaction limited to contact area Allergic Contact Dermatitis (ACD)(*) eczema Type IV Hypersensitivity
Reaction severe itching (delayed--6 to 48 hours) vesicles/blisters dryness cracking crusting desquamation reaction may extend beyond glove area (up the arm) (*) appearance similar to irritant contact dermatitis; difference is the extent (within or beyond glove border) of the reaction (*) chemical sensitivity falls within this type of reaction Immediate Allergic Urticaria itching Type I Hypersensitivity Reaction urticaria (immediate-minutes to 1 hour) erythema edema pruritis swelling Skin reactions can be affected by other factors.
This condition can be difficult to diagnose and is often confused with type IV hypersensitivity
reaction, eczema, herpes simplex virus (HSV), and burns, potentially leading to suspicion of child abuse.