Latex allergy is probably similar to other sensitivities or allergies, such as penicillin allergy or insect allergy, with a decline in sensitivity with time if no additional exposure occurs. Rash as you mention could be contact urticaria or contact dermatitis, depending on the characteristics of the rash and the time course of onset and resolution.
The diagnosis of latex allergy is based upon in vitro demonstration of specific-IgE to natural latex proteins or the more specific skin test to latex proteins, although there is no approved extract in the US although it is available in other countries. Prick skin testing is performed with 0.001 to 1 mg/ml of latex proteins. Some allergists/immunologists use “homemade” latex extracts utilizing latex gloves incubated in saline or buffer or prick testing through a latex glove. These tests are non-standardized and could expose your patient to a high level of latex protein. However, I would not consider your patient at great risk since the original reaction was confined to the skin. I could not find any specific epidemiologic studies describing a decline in sensitivity with avoidance, only an increase in sensitivity with exposure.
I would reassure the patient’s mother with information related to other allergens and the potential to lose sensitivity with time. I would be confident that the lack of symptoms with contact with natural rubber products is reliable evidence of lack of sensitivity. However, I would perform the in vitro test for latex specific-IgE if the original rash was urticarial or immediate in onset. Although I could not find medical literature specifying the magnitude of decline in latex specific-IgE with time, the experience of describing the increase in latex allergy with exposure (Tarlo), the lack of reports of latex allergy prior to the increased use of latex gloves in general medical and dental care (Charous; Kelly) and the decline in specific-IgE to other allergens with avoidance are sufficient for me to reassure her that allergic subjects can have resolution of latex allergy.
I hope this information is of help to you and your practice. I have copied a question from the ATE archives related to diagnosis of latex allergy.
Latex Allergy: Where Are We Now and How Did We Get There?
Kelly KJ, Sussman G
J Allergy Clin Immunol Pract. 2017;5(5):1212.
Latex allergy emerged as an epidemic of anaphylaxis, occupational asthma, and clinical dilemmas in the 1980s. A systematic recognition, investigation, discovery, epidemiology, and prevention strategy followed. International attention and collaborations of investigators, government agencies, manufacturing, and health policy resulted in near elimination of a global epidemic. This article summarizes nearly 4 decades of work in control of this epidemic and focuses attention on future problems that still require resolution.
Tarlo, Susan M., Gordon L. Sussman, and D. Linn Holness. "Latex sensitivity in dental students and staff: a cross-sectional study." Journal of allergy and clinical immunology 99.3 (1997): 396-400.
Charous, B. Lauren, et al. "Natural rubber latex allergy in the occupational setting." Methods 27.1 (2002): 15-21.
30 year old female wants to know if she is allergic to latex. Relevant history: putting on gloves causes hand swelling and she feels dyspneic. Healthy otherwise, no hx of spinda bifida, no frequent surgeries, no asthma, no allergic rhinitis, no food allergies. No hx of anaphylaxsis. Works in office position as clerk, no hx of working in the medical field or rubber/tire industry. Latex IgE (Quest) 0.31 ClassII. Do I tell her she is allergic?
Unfortunately, there is no definitive answer with the information we have. So you might consider a latex skin test and challenge. I would consider asking her to bring in the latex gloves that have caused a reaction (hand swelling and dyspnea) in the past and observe her wearing the gloves. If no reaction occurred it would strongly support a position that she was not allergic to latex. You might also, simultaneously, perform pre- and post- pulmonary function tests as objective confirmation of obstruction if she complained of shortness of breath but did not exhibit and visible cutaneous manifestations. If this type of challenge was negative, what we normally do is prick with the liquid from the soaked latex glove, and then if that is negative, apply a wet glove to the forearm and prick through the glove. A positive test to any one of these challenges would then give you much more confidence in making a diagnosis of latex allergy. if all of the above were negative using the same gloves she has used in the past it would certainly put in question a diagnosis of latex allergy.
If, however, you do not wish to perform such tests, then on the basis only of her in vitro tests, I would think the safest thing to do would be to say she is allergic to latex, but as you know, we would not know this with any certainty.
Thank you again for your inquiry and we hope this response is helpful to you.
Phil Lieberman, M.D.
All my best.
Dennis K. Ledford, MD, FAAAAI