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Poison ivy - oak - sumac dermatitis in Adult
See also in: External and Internal Eye
Other Resources UpToDate PubMed

Poison ivy - oak - sumac dermatitis in Adult

See also in: External and Internal Eye
Contributors: Susan Burgin MD, Lowell A. Goldsmith MD, MPH
Other Resources UpToDate PubMed

Synopsis

Poison ivy, poison oak, and poison sumac dermatitis is a contact dermatitis (type IV delayed hypersensitivity immune reaction) to an oily resin (urushiol) found on the leaves and in the stems and roots of plants of the Rhus genus (poison ivy, oak, and sumac). The dermatitis occurs in previously sensitized individuals, usually appearing 48 hours after antigen exposure. It is typically seen on the extremities at sites of contact with the plant and appears as erythematous, linear plaques with associated vesicles and bullae. If not washed away, the resin may be easily and unwittingly transferred to other body locations, including the trunk, genital area, and face, where it will incite the same reaction. Pruritus is generally severe.

Black dot (or black spot) poison ivy is the presence of black residue on the skin surface that occurs when a high concentration of urushiol contacts the skin and undergoes oxidization in the presence of moisture.

Poison ivy, oak, or sumac dermatitis can occur in people of all races and ethnicities and ages, although elderly individuals and very young children may be less susceptible. Pruritus is often severe. Scratching does not spread the eruption: vesicles and plaques first appear at sites of contact with high concentrations of antigen and then, as the immune response increases, skin that has contacted lower antigen concentrations becomes involved. The contact dermatitis will persist for 3-4 weeks if not treated.

Codes

ICD10CM:
L23.7 – Allergic contact dermatitis due to plants, except food

SNOMEDCT:
200823002 – Allergic dermatitis due to poison ivy

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Diagnostic Pearls

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Differential Diagnosis & Pitfalls

Black dot poison ivy:
  • Melanocytic lesions including melanoma

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Management Pearls

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Therapy

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References

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Last Reviewed:03/05/2017
Last Updated:11/10/2022
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Poison ivy - oak - sumac dermatitis in Adult
See also in: External and Internal Eye
A medical illustration showing key findings of Poison ivy - oak - sumac dermatitis : Erythema, Eyelids, Linear configuration, Scattered many, Tense vesicles, Arms, Legs
Clinical image of Poison ivy - oak - sumac dermatitis - imageId=113052. Click to open in gallery.  caption: 'Vesicular, erythematous plaques, some linear, and scattered vesicles on the arm.'
Vesicular, erythematous plaques, some linear, and scattered vesicles on the arm.
Copyright © 2023 VisualDx®. All rights reserved.