Patch Testing to Paraphenylenediamine: The North American Contact Dermatitis Group Experience (1994-2018)

Background/Objectives: Paraphenylenediamine (PPD) is an aromatic amine dye that may cause allergic contact dermatitis. This study examines the epidemiology of allergic patch test reactions to PPD. Methods: This retrospective analysis characterizes individuals tested to PPD (1% petrolatum) by the North American Contact Dermatitis Group (1994-2018). Demographics and dermatitis site(s) were compared between PPD-allergic and PPD-negative patients. PPD reactions were analyzed by reaction strength, clinical relevance, occupational relatedness, and source as well as coreactivity with structurally related compounds. Results: Of 54,917 patients tested to PPD, 3095 (5.6%) had an allergic patch test reaction. Compared with PPD-negative patients, PPD-allergic patients had significantly greater odds of age >40 years (odds ratio [OR] 1.55 [95% confidence interval; CI 1.43-1.69]) and female gender (OR 1.52 [95% CI 1.41-1.66]), but lower odds of being White (OR 0.66 [95% CI 0.60-0.71]). The most common primary anatomic sites of dermatitis were face (25.5%), hands (21.9%), and scattered/generalized pattern (15.5%). Over half (55.3%) of PPD reactions were ++ or +++ at the final reading and 60.9% were currently relevant. Common exposure sources included hair dye (73.5%) and clothing/shoes/apparel (3.9%). Occupationally related reactions occurred in 8.3%, most commonly in hairdressers/cosmetologists (72.8%). The most common coreactions were benzocaine (11.3%), N-isopropyl-N'-phenyl-p-phenylenediamine (6.7%), disperse dye mix (6.5%), and black rubber mix (5.1%). Conclusions: The 24-year percentage of allergic reactions to PPD was 5.6%. PPD allergy was associated with female gender and age >40 years. PPD allergic patients were less likely to be White. Allergic reactions were usually clinically relevant and hair dye was the most frequently identified source.

Trends in the Prevalence of Methylchloroisothiazolinone/Methylisothiazolinone Contact Allergy in North America and Europe

Importance

The common use of isothiazolinones as preservatives is a global cause of allergic contact dermatitis. Differences in allowable concentrations of methylisothiazolinone (MI) exist in Europe, Canada, and the US.

Objective

To compare the prevalence of positive patch test reactions to the methylchloroisothiazolinone/methylisothiazolinone (MCI/MI) combination and MI alone in North America and Europe from 2009 to 2018.

Design, Setting, and Participants

This retrospective analysis of North American Contact Dermatitis Group, European Surveillance System on Contact Allergies (ESSCA), and the Information Network of Departments of Dermatology (IVDK) databases included data from patients presenting for patch testing at referral patch test clinics in North America and Europe.

Exposures

Patch tests to MCI/MI and MI.

Main Outcomes and Measures

Prevalence of allergic contact dermatitis to MCI/MI and MI.

Results

From 2009 to 2018, participating sites in North America and Europe patch tested a total of 226 161 individuals to MCI/MI and 118 779 to MI. In Europe, positivity to MCI/MI peaked during 2013 and 2014 at 7.6% (ESSCA) and 5.4% (IVDK) before decreasing to 4.4% (ESSCA) and 3.2% (IVDK) during 2017 and 2018. Positive reactions to MI were 5.5% (ESSCA) and 3.4% (IVDK) during 2017 and 2018. In North America, the frequency of positivity to MCI/MI increased steadily through the study period, reaching 10.8% for MCI/MI during 2017 and 2018. Positive reactions to MI were 15.0% during 2017 and 2018.

Conclusions and Relevance

The study results suggest that in contrast to the continued increase in North America, isothiazolinone allergy is decreasing in Europe. This trend may coincide with earlier and more stringent government regulation of MI in Europe.

Acute hemorrhagic edema of infancy: guide to prevent misdiagnosis

We report the case of a 10-month-old previously healthy boy who presented with acute rash, edema, and low-grade fever in the setting of recent diarrhea. We differentiate between acute hemorrhagic edema of infancy (AHEI) and Henoch-Schönlein purpura (HSP).

Guttate psoriasis outcomes

Guttate psoriasis (GP) typically occurs following an acute infection such as streptococcal pharyngitis. It is thought to have a better prognosis than chronic plaque psoriasis (PP). This retrospective cohort study of 79 patients with GP aims to assess the likelihood of developing PP after the first episode of GP as well as compare clinical and laboratory data in patients with GP who do and do not develop PP.

Anaphylactic reaction to bacitracin ointment

We report a case of an 11-year-old boy who experienced an anaphylactic reaction after administration of bacitracin ointment. After falling and scraping his left elbow, bacitracin ointment was applied to the wound. Within minutes, he experienced an adverse reaction consisting of bilateral pruritus of the feet, which quickly progressed to his head; diaphoresis; nausea; vomiting; facial pallor; and hives. An epinephrine injection was administered and the boy immediately felt better. He was taken to the emergency department and given intravenous methylprednisolone sodium succinate and intravenous diphenhydramine hydrochloride. He was kept for observation, recovered well, and was discharged with prescriptions for prednisone and diphenhydramine hydrochloride. We discuss other similar cases so physicians continue to be aware of this rare yet potentially life-threatening reaction to a commonly used medication.

Telangiectatic erythematous cutaneous reaction to an implantable cardioverter defibrillator

A 76-year-old man developed progressive blanchable reticulate erythema at the implantation site of his third implantable cardioverter defibrillator (ICD). Despite reports of allergic contact dermatitis to implantable devices, extensive routine patch testing in our patient failed to identify a responsible allergen. The clinical presentation and pathologic evidence were consistent with reticular telangiectatic erythema that has been reported overlying pacemakers and, in the English literature recently, overlying ICDs in two patients. Reticular telangiectatic erythema is a benign reactive condition that is possibly due to a combination of aberrant local circulatory and physical forces such as heat, electric fields, or magnetic fields.

Contact dermatitis due to printer's ink in a milk industry employee: case report and review of the allergen paraphenylenediamine

Paraphenylenediamine is a common cause of occupational dermatoses in hairdressers, metallurgy workers, and others. Hand dermatitis developed in an employee of a milk packaging facility. The employee's hands were exposed to milk cartons embossed with wet printer's ink on a daily basis for 2 years. The worker was evaluated through a history, physical examination, and patch testing with 50 standard allergens. Patch testing revealed a positive reaction to paraphenylenediamine. The hand dermatitis resolved once the patient instituted protective measures. The worker's reaction might represent a delayed-type hypersensitivity reaction to printer's ink that contained this agent. More likely, the inciting agent was some other ingredient of the printer's ink that cross-reacts with paraphenylenediamine.

Chloroxylenol causing hand dermatitis in a plumber

Chloroxylenol use has increased and is found in many over-the-counter preparations. Although not a common sensitizer, chloroxylenol's role as a contact allergen and relevance, when positive patch tests are found, is often high. Pre-patch test assessment generally does not identify chloroxylenol as a causative agent. It is increasingly found in liquid soaps particularly in industry and specifically in the health care environment. Even as a wash-off product, this allergen can be a hidden cause of allergic contact dermatitis.

Contact urticaria from xylene

Xylene is widely used in medical technology, but there are many concerns about its safety. A 52-year-old woman, employed as a histotechnician, presented with burning, swollen hands. Patch testing and a visit to her place of work confirmed exposure and sensitivity, in the form of contact urticaria, to xylene. The use of xylene-resistant gloves resulted in clearing of the dermatitis. Establishing the diagnosis of contact urticaria from xylene allowed the patient to be cured of her dermatitis and continue working.

Contact dermatitis to foods and spices

Cutaneous reactions to foods and spices occur in both the workplace and at home in those who grow, handle, prepare, or cook food. As spices are also used in cosmetics and perfumes other exposures are found. Several patterns have been described upon contact with food including irritant contact dermatitis, allergic contact dermatitis, contact urticaria, phototoxic contact dermatitis, and protein contact dermatitis. The purpose of this article is to review the approach to a patient suspected of having a cutaneous reaction to food or spices, as well as discuss these reactions and the allergens that cause them.

Elephantiasis nostras of the lips: a case report

Elephantiasis nostras (EN) is a clinical entity that usually presents as a persistent swelling of the lower extremities. It has been related to recurrent lymphangitis of bacterial origin that causes a fibrosis and thickening of both epidermal and connective tissue. Although very rare, EN has been previously reported in the lips. This is the first case reported in the oral medicine literature that describes EN involving the lips. We describe the clinical features and a differential diagnosis of the lip lesions and a treatment protocol to which this patient has responded. A diagnosis of EN should be entertained in patients with chronically edematous, scaling lip lesions.