Dermatology disorders

Interactive Quiz: Abdominal Rash

What's Your Diagnosis?

Welcome to Consultant360's latest interactive diagnostic quiz. Over the next few pages, we'll present a case and ask you to make the diagnosis and treat the patient. Along the way, we'll provide details about the case, and at the end, we'll share the patient's outcome.

Ready to get started?

First, let’s meet the patient.

A 22-year-old male college student presented to primary care with a pruritic rash on his mid abdomen for the past 2 weeks. He reported mild to moderate pruritus and had been scratching the area above his belt buckle.

History. He had not tried any treatments. He had no other comorbidities but stated that he had developed a similar rash in the past. He is physically active on and off campus, and he has frequent contact with recreational equipment, a laptop, a cell phone, ear buds, musical instruments, costume jewelry, keys, coins, sunglasses, belt buckles, and jeans.

Physical examination. The patient’s initial physical examination revealed a localized, 4.0 × 2.5-cm, erythematous, eczematous rash, with a symmetric pattern localized at the site of contact, the mid-central abdomen above his belt buckle. The erythematous base had overlying pruritic papules but no vesicles, lichenification, or hyperpigmentation.

Take a look at the patient’s intake photo

The Patient's Intake Photo

What's your diagnosis?

See if you were correct!

Answer: B, Allergic contact dermatitis

The patient received a diagnosis of nickel allergic contact dermatitis (Ni-ACD) based on his history and clinical presentation, without the definitive diagnosis of patch testing, which is the gold standard for ACD diagnosis.1 Nickel is the most commonly detected cutaneous allergy.2

Who has a higher risk for ACD?

Find out!

Answer: A, Atopic dermatitis

Discussion. ACD is a complicated delayed-hypersensitivity reaction requiring previous sensitization and an external trigger.1 Patients with a history of atopic dermatitis have an increased risk of developing Ni-ACD.3 There are various metal allergy presentations ranging from localized to systemic reactions.2 Females are 4 times more likely to develop Ni-ACD than are males.4

In the United States, ACD has an annual estimated cost of $1.6 billion.5

What are the most prevalent metal allergens?

See the answer!

Answer: C, Nickel, cobalt, chromium

Metal allergy is an environmental disorder that is provoked by increased cutaneous exposure to metal ions. Nickel, cobalt, and chromium are the 3 most prevalent metal allergens. Cutaneous symptoms of metal allergy usually appear within 24 hours up to days after exposure.3 The occurrence rate of metal allergy is high in the general population, with approximately 17% of women and 3% of men being allergic to nickel, and 1% to 3% of both sexes being allergic to cobalt and chromium.6 The recurrence rate of Ni-ACD is dependent on exposure, and sensitization is lifelong.

In our patient’s case, the sensitization was evoked by the exogenous allergen, nickel. The nickel from a belt buckle entered the epidermis through a compromised skin barrier at the patient’s waistband. Sweat and friction increased the release of nickel and the patient’s sensitivity to it.

The aim of Ni-ACD treatment is accurate diagnosis, avoidance, and prevention.3 First-line treatment is avoidance of the nickel allergen,7 particularly among patients with atopic dermatitis, in whom the preemptive avoidance of nickel may decrease sensitization and related morbidity.3

Other ACD therapies are directed at alleviating the symptoms and preventing recurrence.2 Topical midpotency corticosteroids and antihistamines offer temporary relief of pruritus. Corticosteroid ointments contain fewer sensitizing preservatives and are recommended over creams and lotions.1 Supportive care options include cool compresses, emollients, Burow solution, calamine, and oatmeal baths.1 Established Ni-ACD treatment options include UV-B phototherapy and corticosteroids.2

Specific patient education includes complete avoidance of sources of nickel, such as buckles, buttons, clasps, and zippers on clothing; electronics (eg, mobile phones, laptops, tablets, gaming controllers, headsets); coins; keys; jewelry and piercings; foods with nickel content; musical instruments; cooking utensils; razors; eyeglass frames; dental appliances; and the possible occupational exposure. Education also includes the use of nickel-free alternatives.8

Dimethylglyoxime-ammonia spot testing is recommended for patients to test metal-containing items for nickel content prior to purchasing or wearing them.2

Outcome of the case

Outcome of the Case

The therapy chosen for our patient was to eliminate his exposure to the nickel allergen. His symptoms resolved with avoidance of the nickel-containing belt buckle. Complete resolution of the dermatitis occurred within 2 weeks.


  1. Admani S, Jacob SE. Allergic contact dermatitis in children: review of the past decade. Curr Allergy Asthma Rep. 2014;14(4):421.
  2. Tuchman M, Silverberg JI, Jacob SE, Silverberg N. Nickel contact dermatitis in children. Clin Dermatol. 2015;33(3):320-326.
  3. Goldenberg A, Admani S, Pelletier J, Jacob S. Belt buckles—increasing awareness of nickel exposure in children: a case report. Pediatrics. 2015;​136(3):e691-e693.
  4. Lu LK, Warshaw EM, Dunnick CA. Prevention of nickel allergy: the case for regulation? Dermatol Clin. 2009;27(2):155-161.
  5. Matiz C, Hsu JW, Paz Castanedo-Tardan M, Jacob SE. Allergic contact dermatitis in children: a review of international studies. G Ital Dermatol Venereol. 2009;144(5):541-556.
  6. Thyssen JP, Menné T. Metal allergy—a review on exposures, penetration, genetics, prevalence, and clinical implications. Chem Res Toxicol. 2010;​23(2):​309-318.
  7. Fonacier LS, Aquino MR, Mucci T. Current strategies in treating severe contact dermatitis in pediatric patients. Curr Allergy Asthma Rep. 2012;12(6):​599-606.
  8. Goldberg A, Silverberg N, Silverberg JI, Treat J, Jacob SE. Pediatric allergic contact dermatitis: lessons for better care. J Allergy Clin Immunol Pract. 2015;3(5):661-668.