Morphology
Black spot poison ivy Carole McClanahan1, BA, Adam Asarch2, MD, and Brian L. Swick2,3,4, MD
1
Carver College of Medicine, 2 Department of Dermatology, 3Department of Pathology, University of Iowa, Iowa, IA, USA, and 4 Iowa City Veterans Affairs Medical Center, Iowa, IA, USA Correspondence Brian Swick, MD Department of Dermatology University of Iowa 40025 Pomerantz Family Pavilion 720 Melrose Avenue Iowa City, IA 52246, USA E-mail: [email protected] Conflicts of interest: None.
Case report A previously healthy 11-year-old girl presented with an intensely pruritic widespread eruption. The patient reported that this had been ongoing for two days. It initially started with itching and redness of the inner thighs and spread to involve the entire face as well as the arms, neck, and abdomen. She notably developed black spots on her arms as well. Physical examination revealed erythematous eczematous papules and plaques on the neck, arms, legs, and abdomen. Diffuse erythema and swelling of the face was noted (Fig. 1). In addition, there were scattered erythematous papules with central black discolored macules on her arms (Fig. 2). The black material could not be removed with saline gauze or isopropyl alcohol. No other skin lesions of concern were identified in the areas examined. A diagnosis of black spot poison ivy (Toxicodendron dermatitis) was made.
necrosis, in addition to classic features of acute allergic contact dermatitis.2 When Toxicodendron plants are injured and their sap is exposed to air, oleoresin turns coal-black.3 Contact with a sufficient concentration of this oleoresin will produce black spot poison ivy.4 The resultant black spots are quite evident; thus, diagnosis can generally be made clinically. If there is doubt, diagnosis can be aided by pathology.
Discussion
752
Poison ivy is characterized by a generalized, pruritic, erythematous rash with vesicles and papules in a linear distribution.1 Black spot poison ivy presents in a similar fashion, with the addition of black lacquer-like macules with surrounding erythema. Our patient presented with these classic erythematous papules and plaques studded with black shiny spots. Histology of these lesions reveals yellow material in the stratum corneum with epidermal International Journal of Dermatology 2014, 53, 752–753
Figure 1 Eczematous erythematous plaques on the face and neck with prominent facial erythema and swelling ª 2014 The International Society of Dermatology
Black spot poison ivy
McClanahan, Asarch and Swick
Morphology
Although a rare phenomenon, black spot poison ivy remains an important diagnosis to consider in evaluating a patient with a pruritic, erythematous rash studded with glossy black macules. An accurate diagnosis can alleviate patient fears about pigmented or necrotic lesions and can allow for prompt treatment. An accurate diagnosis can also allow for proper patient counseling to prevent future re-exposure.7 References
Figure 2 Eczematous plaque with areas of vesiculation and focal circular black macule
Treatment of black spot poison ivy, like poison ivy, involves oral and topical steroids, combined with antihistamines if the patient continues to experience pruritus.4,5 Typically, the rash resolves within 1–3 weeks, and patients do not require further monitoring.6 We treated our patient with a 20-day prednisone taper, topical clobetasol, and hydroxyzine. She responded well to treatment and did not require further follow-up.
ª 2014 The International Society of Dermatology
1 Fisher A. Poison ivy/oak dermatitis part I: prevention – soap and water, topical barriers, hyposensitization. Cutis 1996; 57: 384–386. 2 Hurwitz RM, Rivera HP, Guin JD. Black-spot poison ivy dermatitis: an acute irritant contact dermatitis superimposed upon an allergic contact dermatitis. Am J Dermatopathol 1984; 6: 319–322. 3 Guin JD. The black spot test for recognizing poison ivy and related species. J Am Acad Dermatol 1980; 2: 322–333. 4 Mallory SB, Miller OF, Tylor WB. Toxicodendron radicans dermatitis with black lacquer deposit on the skin. J Am Acad Dermatol 1982; 6: 363–368. 5 Schram SE, Willey A, Lee PK, et al. Black-spot poison ivy. Dermatitis 2008; 19: 48–51. 6 Baer RL. Poison ivy dermatitis. Cutis 1990; 46: 34–36. 7 Kurlan JG, Lucky AW. Black spot poison ivy: a report of 5 cases and a review of the literature. J Am Acad Dermatol 2001; 45: 246–249.
International Journal of Dermatology 2014, 53, 752–753
753
Black spot poison ivy Carole McClanahan1, BA, Adam Asarch2, MD, and Brian L. Swick2,3,4, MD
1
Carver College of Medicine, 2 Department of Dermatology, 3Department of Pathology, University of Iowa, Iowa, IA, USA, and 4 Iowa City Veterans Affairs Medical Center, Iowa, IA, USA Correspondence Brian Swick, MD Department of Dermatology University of Iowa 40025 Pomerantz Family Pavilion 720 Melrose Avenue Iowa City, IA 52246, USA E-mail: [email protected] Conflicts of interest: None.
Case report A previously healthy 11-year-old girl presented with an intensely pruritic widespread eruption. The patient reported that this had been ongoing for two days. It initially started with itching and redness of the inner thighs and spread to involve the entire face as well as the arms, neck, and abdomen. She notably developed black spots on her arms as well. Physical examination revealed erythematous eczematous papules and plaques on the neck, arms, legs, and abdomen. Diffuse erythema and swelling of the face was noted (Fig. 1). In addition, there were scattered erythematous papules with central black discolored macules on her arms (Fig. 2). The black material could not be removed with saline gauze or isopropyl alcohol. No other skin lesions of concern were identified in the areas examined. A diagnosis of black spot poison ivy (Toxicodendron dermatitis) was made.
necrosis, in addition to classic features of acute allergic contact dermatitis.2 When Toxicodendron plants are injured and their sap is exposed to air, oleoresin turns coal-black.3 Contact with a sufficient concentration of this oleoresin will produce black spot poison ivy.4 The resultant black spots are quite evident; thus, diagnosis can generally be made clinically. If there is doubt, diagnosis can be aided by pathology.
Discussion
752
Poison ivy is characterized by a generalized, pruritic, erythematous rash with vesicles and papules in a linear distribution.1 Black spot poison ivy presents in a similar fashion, with the addition of black lacquer-like macules with surrounding erythema. Our patient presented with these classic erythematous papules and plaques studded with black shiny spots. Histology of these lesions reveals yellow material in the stratum corneum with epidermal International Journal of Dermatology 2014, 53, 752–753
Figure 1 Eczematous erythematous plaques on the face and neck with prominent facial erythema and swelling ª 2014 The International Society of Dermatology
Black spot poison ivy
McClanahan, Asarch and Swick
Morphology
Although a rare phenomenon, black spot poison ivy remains an important diagnosis to consider in evaluating a patient with a pruritic, erythematous rash studded with glossy black macules. An accurate diagnosis can alleviate patient fears about pigmented or necrotic lesions and can allow for prompt treatment. An accurate diagnosis can also allow for proper patient counseling to prevent future re-exposure.7 References
Figure 2 Eczematous plaque with areas of vesiculation and focal circular black macule
Treatment of black spot poison ivy, like poison ivy, involves oral and topical steroids, combined with antihistamines if the patient continues to experience pruritus.4,5 Typically, the rash resolves within 1–3 weeks, and patients do not require further monitoring.6 We treated our patient with a 20-day prednisone taper, topical clobetasol, and hydroxyzine. She responded well to treatment and did not require further follow-up.
ª 2014 The International Society of Dermatology
1 Fisher A. Poison ivy/oak dermatitis part I: prevention – soap and water, topical barriers, hyposensitization. Cutis 1996; 57: 384–386. 2 Hurwitz RM, Rivera HP, Guin JD. Black-spot poison ivy dermatitis: an acute irritant contact dermatitis superimposed upon an allergic contact dermatitis. Am J Dermatopathol 1984; 6: 319–322. 3 Guin JD. The black spot test for recognizing poison ivy and related species. J Am Acad Dermatol 1980; 2: 322–333. 4 Mallory SB, Miller OF, Tylor WB. Toxicodendron radicans dermatitis with black lacquer deposit on the skin. J Am Acad Dermatol 1982; 6: 363–368. 5 Schram SE, Willey A, Lee PK, et al. Black-spot poison ivy. Dermatitis 2008; 19: 48–51. 6 Baer RL. Poison ivy dermatitis. Cutis 1990; 46: 34–36. 7 Kurlan JG, Lucky AW. Black spot poison ivy: a report of 5 cases and a review of the literature. J Am Acad Dermatol 2001; 45: 246–249.
International Journal of Dermatology 2014, 53, 752–753
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