Author: V. Dimov, M.D., Allergist/Immunologist, Assistant Professor at University of Chicago
Reviewer: S. Randhawa, M.D., Allergist/Immunologist, Assistant Professor at NSU
A 53-year-old female is in the clinic for evaluation of her complaints of feeling of skin "burning", discomfort and mild erythema with different clothes. These symptoms mostly affect the lower part of the body but also occasionally the upper extremities. They started approximately 6 years ago after she used a hair dye with quaternary ammonium. An allergist at the time performed contact allergy testing with T.R.U.E. Test and, as per patient, this test was positive for cobalt, nickel and quaternary ammonium. It has been a struggle for her to avoid the use of products with quaternary ammonium, also known as benzalkonium chloride, which is widely used as a disinfectant. She is able to tolerate pure cotton clothes, but she has difficulty finding those in the stores.
Past medical history
Her past medical history is remarkable for the above-referenced symptoms of contact dermatitis/textile dermatitis, as well as anxiety and panic attacks.
Drug allergies include Bactrim with rash and also possiblle allergic reactions with Augmentin, Levaquin and amoxicillin, and pruritus but no rash with Motrin and Cipro.
Her current medications include Ativan b.i.d.
Her family history and social history are unremarkable.
The physical examination is normal.
Procedures: CBC, differential and CMP were ordered.
What is the most likely diagnosis?
This is a patient with a history of contact dermatitis with positive T.R.U.E. Test to cobalt, nickel and quaternary ammonium, which is also know as benzalkonium chloride, with a suspected diagnosis of textile dermatitis. Interestingly, she does not actually have a skin rash. It is mostly manifested by burning sensation and pruritus with some mild erythema. However, the presence of rash is important for the conclusive diagnosis of dermatitis. In any case, textile dermatitis can be caused by irritant reactions to textile fibers or contact allergy to textile dyes and finishing chemicals. It is important to be aware that dispersed dyes can also cause a reaction in sensitive patients.
What would you suggest in terms of diagnostic tests?
We recommended that she has CBC with differential count and CMP for basic screening for other causes of the sensation of skin "burning" and pruritus. Also, we advised her to take loratadine 10 mg p.o. daily, and to use "All Clear" detergent without any perfumes to wash her clothing. She will request the T.R.U.E. Test results from her previous allergist. There is currently no evidence of environmental sensitization to trees, gasses, mold and no evidence of symptoms for allergic rhinitis, conjunctivitis, asthma or food allergy and we decided to postpone skin prick testing to environmental allergens and food allergens at this time because it is not likely that IgE mediated allergy plays a role in this clinical setting. After we review the T.R.U.E. Test results, it may be reasonable to refer her to a dermatologist who can perform an expanded T.R.U.E. test for more contact allergens (50 or 74 rather than the initial 25 allergens included in T.R.U.E.) to see if any other allergens play a role. It is recommended to avoid the triggering substances or textiles that cause irritation in this patient.
The patch test for contact dermatitis is expensive. The cost is $30 per potential allergen, and a 20-allergen TRUE test would cost around $160-600. The CPT code is 95044, it is paid only contact dermatitis is listed as ICD-9 code for the visit (source: http://www.aaaai.org/ask-the-expert/coding-for-the-Atopy-Patch-Test.aspx). A typical charge is in the range of $160 (professional fee of $40, facility fee $120).
Thin-Layer Rapid-Use Epicutaneous Test (patch test) misses allergens in 12.5% of patients with contact dermatitis http://goo.gl/nqUsn