Q:

9/5/2012
I have a patient in consultation that breaks out in localized hives after carrying plastic grocery bags. Patient states she is okay with all other plastics. Any information regarding this?

A:

Thank you for your inquiry.

There is no information of which I am aware in the medical literature about localized hives related specifically to carrying plastic grocery bags. However, the Internet itself is full of anecdotal reports of localized hives due to carrying plastic grocery bags. There are a number of links to these anecdotal reports, and I have copied three below for you.

If you visit these links, you will see that these reactions appear to be due not to the plastic, but actually due to the pressure induced by carrying the plastic bags. As you know, the plastic bags have very narrow bands, and these exert pressure on the skin and subcutaneous tissue. Therefore such cases have probably been due to pressure urticaria/angioedema or delayed pressure urticaria/angioedema.

There is an extensive body of literature on pressure urticaria/angioedema, and one can test for this condition by applying weights to patient's forearms (see abstract below). This can be done using a plastic grocery bag and another carrier such as a purse with a thin strap loaded with weights. For the weights, you could use canned goods, for example.

You can certainly test the hypothesis that it is the pressure by seeing if you can reproduce the event in-office using another vehicle such as the purse with a thin strap loaded with weights equal to that placed in a plastic grocery bag. You can test two arms simultaneously with equal weights; one with the purse and the other with the grocery bag.

Thank you again for your inquiry and we hope this response is helpful to you.

http://www.medhelp.org/posts/Allergy/Reaction-to-certain-type-of-plastic-bag/show/4417

http://www.cnn.com/2011/11/25/health/plastics-perfumes-new-allergies/index.html

http://www.steadyhealth.com/Delayed_Pressure_Urticaria_t77793.html?page=5

Journal of the American Academy of Dermatology
Volume 29, Issue 6 , Pages 954-958, December 1993
Diagnosis and incidence of delayed pressure urticaria in patients with chronic urticaria
Abstract
Background: The incidence of delayed pressure urticaria (DPU) may have been underestimated, particularly in patients with widespread wheals of concurrent idiopathic urticaria, because of difficulty in recognizing the association between pressure-related swellings and the preceding physical stimulus. Diagnostic tests for DPU have not been done routinely in studies of urticaria and have not been compared.
Objective: Our purpose was to establish the incidence of DPU and other physical urticarias in patients with chronic urticaria and to compare two reproducible pressure challenge tests.
Methods: One hundred thirty- five patients were tested for immediate dermographism, for DPU and, when indicated by the history, for cholinergic and/or cold urticaria. In patients with pressure-related symptoms, pressure challenge testing with a dermographometer (100 gm/mm2) was compared with a test that involves the application of 1.5 cm diameter weighted rods and more closely resembles a naturally occurring pressure stimulus.
Results: Physical urticarias were present in 96 patients (71%). Thirty patients (22%) had immediate dermographism, 50 (37%) had DPU, 15 (11%) had cholinergic urticaria, and 3 (2%) had cold urticaria. A 70-second pressure challenge with the dermographometer gave results comparable to the use of the weighted rods.
Conclusion: DPU appears to be more common in chronic urticaria than previously reported and is present in some patients who do not report pressure-related wheals. (J Am Acad Dermatol 1993 Dec;29(6):954-8).

Sincerely,
Phil Lieberman, M.D.

AAAAI - American Academy of Allergy Asthma & Immunology