Derm Dx: A rare type of urticaria

Adrenergic urticaria is a rare type of urticaria induced by stress and is characterized by transient outbreaks of widespread pruritic, urticarial papules surrounded by a striking halo of hypopigmented, vasoconstricted skin. It must be distinguished from the more common cholinergic...

Submit your diagnosis to see full explanation.

Adrenergic urticaria is a rare type of urticaria induced by stress and is characterized by transient outbreaks of widespread pruritic, urticarial papules surrounded by a striking halo of hypopigmented, vasoconstricted skin. It must be distinguished from the more common cholinergic urticaria, which consists of a papule in the center of a large erythematous flare rather than the blanched halo of adrenergic urticaria.¹

Adrenergic urticaria typically happens due to stress, while cholinergic urticaria commonly occurs with sweating and exercise. Adrenergic urticaria occurs more commonly in patients with a history of emotional lability or psychiatric diagnoses, and flares typically occur 10 to 15 minutes after patients experience a significant stressor and anxiety.^1,2 Episodes can result from a variety of triggers, including emotional upset, tension, stress, coffee, chocolate, spices, and ginger.^1,3 While the precise mechanism of pathogenesis has yet to be elucidated, it is likely related to high levels of circulating catecholamines, with the characteristic surrounding pale halo resulting from catecholamine-induced vasoconstriction.

 

In terms of laboratory values in patients with adrenergic urticaria, serum catecholamine and immunoglobulin E (IgE) levels are elevated, while histamine and serotonin levels remain within normal limits.² Histologically, biopsies demonstrate edematous tissue with a nonspecific, inflammatory infiltrate.

Unlike patients with cholinergic urticaria, the lesion will not be replicated with an intradermal injection of acetylcholine. Instead, diagnosis of adrenergic urticaria can be made by intradermal injection of 5 to 15 ng of epinephrine or 3 to 10 ng of norepinephrine in 0.02 mL of saline, which reproduces the characteristic rash.² Alternatively, clinical response to propranolol can be used to make the diagnosis of adrenergic urticaria.

To treat adrenergic urticaria, in addition to trigger avoidance, up to 40 mg of propranolol administered 3 times a day has been shown to be the most effective.² Propranolol both resolves the rash and decreases the chance for future episodes. Flares will likely recur if propranolol is discontinued in these patients. Antihistamines can also provide some relief. In cases that are refractory to propranolol, anxiolytic benzodiazepines such as clotiazepam have been shown to be efficacious.⁴

Emily Guo, BA, is a medical student, and Maura Holcomb, MD, is a dermatology resident at Baylor College of Medicine in Houston, Texas.

References

1. Shelley WB, Shelley ED. Adrenergic urticaria: a new form of stress-induced hives. Lancet. 1985;2(8463):1031-1033.
2. Hogan SR, Mandrell J, Eilers D. Adrenergic urticaria: review of the literature and proposed mechanism. J Am Acad Dermatol. 2014;70(4):763-766.
3. Chedraoui A, Uthman I, Abbas O, Ghosn S. Adrenergic urticaria in a patient with anti-double-stranded DNA antibodies. Acta Derm Venereol. 2008;88(3):263-266.
4. Kawakami Y, Gokita M, Fukunaga A, Nishigori C. Refractory case of adrenergic urticaria successfully treated with clotiazepam. J Dermatol. 2015;42(6):635-637.