Reviewer: S. Randhawa, M.D., Allergist/Immunologist and Assistant Professor at NSU
A 22-year-old African American female is referred to the clinic for suspected latex allergy. She is to start work as a nurse at the local medical center and she is referred by occupational medicine. The patient has a history of intolerance to latex. Three years ago, she was taking care of her ailing grandmother and was using latex gloves when she reacted with “bumps” on her hands. She also reports that she used an eyelash extender with latex-based glue 5 months ago and she had eyelid swelling after she removed the eyelashes. She also reports history of irritation and itching in the vaginal area when using condoms. A month ago, she was at the hairdresser who was applying hair extenders to her scalp using a latex-based glue. Within six minutes of applying the extenders, she started to complain of feeling a lump in her throat; she started to have shortness of breath, and hives which affected her face, arms, legs, and back. She was sent to the ER where she was given an injection of Benadryl and injection of corticosteroid. Her symptoms resolved within an hour. She has not used the same hair extenders with latex glue or the eyelash application with latex base since then. She denies any reactions to food that may closely react with latex allergens, including kiwi, papaya, passion fruit, bananas, or almonds.
Past medical history (PMH)
Negative.
Medications
None.
Social history
Nonsmoker. No pets. Nursing student.
Family history
No history of allergic disease or reaction to latex.
Physical examination
Vital signs stable. Normal nose and throat exam. Respiratory system: Clear to auscultation bilaterally. Cardiovascular system: Clear S1, S2. Abdomen: Soft, non-tender, non-distended. Extremities: no edema. Skin: no rashes.
What tests would you suggest?
Skin prick testing with latex. If negative, ImmunoCAP test for specific IgE for latex allergens.
Sample form for latex skin prick testing (click to enlarge).
What happened?
Test results (click to enlarge).
Skin prick testing with latex was done using the standard protocol at the clinic. She reacted to histamine with 5 x 5 mm wheal, erythema 20 x 15 mm. She reacted to "wet glove one" with a wheal 5 x 6 mm, erythema 25 x 25 mm. She reacted to "wet glove one solution" with a 3 x 7 mm, erythema 15 x 20 mm. She reacted to "wet glove 2" with a wheal 3 x 10 mm, erythema 15 x 20 mm. She reacted to "wet glove 2 solution" with a wheal 1 x 1 mm, erythema 2 x 2 mm. She reacted to "dry glove" with wheal 2 x 2 mm, erythema 3 x 3 mm. The reaction to saline was negative.
What treatment would you suggest?
This is a patient with latex allergy and she was advised to avoid all latex products including gloves, latex-based glue, hair extenders, condoms, etc. She was advised to discuss workplace avoidance measures and also to avoid foods, which may cross react with latex. She was prescribed an EpiPen and education was provided how to use the EpiPen. Considering the relatively strong reaction to latex during the skin prick test, we gave her Alavert (loratadine) oral dissolving tablet 10 mg x 1 and she was discharged from the clinic without symptoms. A comprehensive list of latex-containing products and cross-reactive foods was provided to the patient.
Final diagnosis
Latex allergy.
Summary
Latex is most often referred to the cytoplasmic exudate of the Hevea brasiliensis tree, hence the name Hev b allergens. There are more than 250 latex proteins but only 13 proteins have been characterized and designated as Hev b allergens. Skin prick reactivity to Hev b 5, 6, 7 identifies 93% of workers allergic to latex.
Latex being collected from a "wounded" rubber tree. Image source: Wikipedia, public domain.
Hevea brasiliensis (Rubber Tree). Image source: Wikipedia, public domain.
Latex allergy, a mind map diagram (click to enlarge).
Tests to rule out latex allergy
- Skin prick test 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. If all of the above are negative using the same gloves the patient has used in the past it would make the diagnosis of latex allergy unlikely. This should be followed by a challenge when appropriate.
- Specific IgE blood test may be helpful but the skin testing is the preferred diagnostic method. sIgE for latex allergy has much lower sensitivity than previously reported - sensitivity was 35%; specificity 98% (Ann of Allergy, Asthma, Imm, 2012). Sensitivity, specificity, NPV, and PPV of latex-specific IgE assay are 91, 72, 96 and 50%, respectively (http://goo.gl/9gX0F).
- Pre- and post- pulmonary function tests as objective confirmation of obstruction if a patients complains of shortness of breath but did not exhibit visible cutaneous manifestations
An approach to performing a test for immediate hypersensitivity to latex:
1. Prick test with the solution obtained from a soaked latex glove left in saline for one hour. Await 15 minutes.
2. If test 1. is negative, place a wet latex glove on the arm for 15 minutes.
3. If there is no response to test 2., prick through the wet latex glove. Await 15 minutes.
4. Simultaneously draw an ELISA for IgE-anti-latex (ImmunoCAP). Await the results of the ELISA before clearing for the surgical procedure.
Evaluation of patient with possible latex allergy. AAAAI Ask the Expert, 2012.
35% of sensitized patients develop allergic reactions to fruits and vegetables that contain proteins that cross-react with latex allergens (passion fruit, kiwi, avocado, banana, chestnuts, papaya, mango, tomato, and wheat).
Patients with history of anaphylaxis should be prescribed emergency epinephrine kits.
References
Latex Allergy: A Short Review. V. Dimov. Allergy Cases, 2008.
Latex Allergy. AFP, 1998.
Latex Allergy. eMedicine Specialties > Emergency Medicine > Allergy & Immunology, 2008.
Latex allergy. Constance H Katelaris. MJA 2006; 185 (6): 339.
Hidden Hazard: Hospitals Target Lurking Latex. WSJ, 02/2008 (subscription may be required).
IgE-mediated latex allergy - An exciting and instructive piece of allergy history. http://goo.gl/i5Tn
Profilin may be a pan-allergen among plants that crossreacts between pollen, fruits, vegetables and latex http://goo.gl/ZUPRQ
Multiple choice questions
Chapter 58: Latex Allergy. Allergy and Immunology Review Corner: Chapter 58 of Pediatric Allergy: Principles & Practices, edited by Donald Y.M. Leung, et al.
Patient information
Latex Allergy. National Institutes of Health.
Latex allergy. Mayo Clinic staff.
Tips to Remember: Latex allergy. AAAAI.
Related reading
Knowing your allergies can save your life - there are different types of latex allergy. Arizona Daily Sun, 2011.
Anaphylaxis caused by latex surgical gloves immediately after starting surgery. Korean J Anesthesiol. 2010 Dec;59(Suppl):S99-S102.
Latex Medical Gloves: Time for a Reappraisal. Int Arch Allergy Immunol 2011;156:234-246 (DOI: 10.1159/000323892).
Diagnosis of latex allergy. AAAAI Ask the Expert, 2011.
Contact dermatitis to latex surgical gloves? There are limited choices for non-latex gloves: vinyl or nitrile. AAAAI, 2011. Hypersensitivity reactions due to nitrile gloves - presence of latex was the cause of the symptoms (JACI, 2012).
Latex immunotherapy: state of the art. Guidelines do not consider allergy to latex as indication to desensitization http://goo.gl/j5UaA
Published: 04/15/2009
Updated: 07/15/2012
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