Black-Spot Poison Ivy

Sarah E. Schram; Andrea Willey; Peter K. Lee; Kimberly A. Bohjanen; Erin M. Warshaw


Dermatitis. 2008;19(1):48-51. 

In This Article

Case Description

A 34-year-old otherwise healthy woman presented with a 10-day history of black “oil patches” on her left arm that began after exposure to her children's toys, which had been left in an outdoor wooded area. Her first symptom was a severe burning sensation of the skin, which was followed by the development of black spots; she also noticed some small asymptomatic blisters. Six days after the onset of the black spots, she applied Neosporin ointment (Johnson&Johnson, New Brunswick, NJ) to the lesions. By the next day (day 7), the area had become quite painful, and she noticed erythema extending from her left wrist to her axilla. She discontinued Neosporin and started using topical hydrocortisone cream on the involved area. On day 8, she developed swelling in her left axilla and was treated at a local urgent care facility with oral prednisone (dose unknown). Because of concern for possible left-arm cellulitis, the patient was transferred to the University of Minnesota Medical Center, where she was seen in the dermatology department. On presentation, there were erythematous and edematous papules and plaques studded with vesicles on the left dorsal forearm. The left volar forearm had numerous black and erythematous plaques with edema, vesicles, and ulcerations (Fig 1). On the abdomen, left foot, bilateral legs, and right arm, there were focal target-shaped edematous erythematous blanching patches and plaques. There were also erythematous plaques in the pubic area and palpable lymph nodes in the left axilla. The next day, the urticarial eruption had spread to involve her back, neck, and periocular area. Her past medical history included seasonal allergic rhinitis and rhinitis in response to animal dander. She had no previous history of contact allergy. A skin biopsy specimen taken from a black plaque on the left volar arm showed dermal and epidermal necrosis, and a skin biopsy specimen from an urticarial plaque on the left arm was consistent with urticaria. Stains were negative for organisms. Blood, urine, and throat cultures were negative. Treatments included a methylprednisolone taper and diphenhydramine.

Figure 1.

Patient's left volar forearm, with black spots and erythematous plaques with edema, vesiculation, and ulceration.

After discharge and 2 days after completing the oral prednisone taper, she developed immediate burning of the skin on the left face, neck, and arm shortly after handling her husband's laundry, which may have been contaminated with poison ivy resin. On day 22 (10 days after discharge), the patient was seen at a local primary care clinic, where oral prednisone was reinitiated; however, the rash continued to worsen, and she was re-admitted to the hospital. On admission (day 23), she was observed to have periorbital erythema and edema with erythematous patches and small punctate black crusts on the anterior neck, abdomen, and left arm. Lyme antibodies and Coxsackie A virus titers were negative; erythrocyte sedimentation rate, C-reactive protein, and kidney function test results were within normal limits. A biopsy specimen from the abdomen demonstrated epidermal and dermal necrosis with a superficial and deep perivascular and periadnexal infiltrate of eosinophils.

Approximately 10 months later, the patient had a recurrence of her symptoms, this time with acute respiratory involvement. She was driving along the road near her property when freshly cut plant material blew in through the window. She experienced immediate intense burning of the left arm and anterior neck and developed difficulty breathing within a few moments. She injected herself with epinephrine and drove to the emergency room, where she was given another dose of epinephrine and intravenous steroids; however, she continued to have wheezing and became unable to phonate. She was immediately intubated and admitted to the hospital. She remained intubated for 4 days before discharge. During the hospitalization, erythema, blistering, and black spots developed in an airborne distribution on the arms and neck (Fig 2 and 3). She was treated with intravenous diphenhydramine, methyl prednisolone, and cimetidine.

Figure 2.

Black spots, erythema, and edema of the anterior neck.

Figure 3.

Black spots, erythema, and edema of the anterior neck.

Since the last episode, she has strictly avoided poison ivy exposure and has not had a recurrence of symptoms; however, she has developed significant scarring from the lesions on her arms and face (Fig 4). She declined further testing including patch testing with Neosporin.

Figure 4.

Scarring on left forearm at sites of black-spot poison ivy dermatitis.


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.
Post as: