Lindsey Dolohanty, MD

Localized bullous pemphigoid

Bullous pemphigoid is a systemic, autoimmune bullous disease that classically presents as widespread urticarial plaques or tense bullae with a predilection in the elderly population.¹

Localized variants of bullous pemphigoid (BP) are rare and have been reported to arise at sites of mechanical trauma, prior radiation, lymphedema, surgical scars, burns, fistulas, and ostomies.^1-3 Although the mechanism remains unclear, the Koebner phenomenon is thought to induce dysregulation of immunologic and vascular factors in sites of mechanical shear and trauma in susceptible individuals.³

Localized BP is an important entity for the dermatologist to be familiar with, as the diagnosis is often delayed. The localized, well-defined skin lesions frequently mimic contact dermatitis. In fact, previous reports have shown the most likely misdiagnosis of localized BP is acute allergic contact dermatitis, stasis dermatitis, and eczematous dermatitis.^4,5

In this patient, histopathologic examination of a biopsy revealed a subepidermal blister with numerous eosinophils. Direct immunofluorescence study of perilesional skin showed strong linear IgG and C3 deposits at the basal membrane level. Serum level of autoantibody to BP180 antigen was elevated. Bacterial culture was positive for Staphylococcus aureus. These findings were suggestive of unilateral, localized BP with superimposed bacterial infection. Initial treatment with an extended course of doxycycline 200 mg twice daily, topical triamcinolone 0.1% ointment twice daily with compression therapy, and leg elevation led to clinical improvement with healing of previous lesions on the leg. At follow-up 3 weeks later, the patient had continued to develop new bullous lesions on the trunk and upper thighs. He was subsequently started on systemic immunosuppressive therapy for generalized bullous pemphigoid.

Importantly, localized BP generally follows a more benign disease course, although long-term follow-up is recommended for monitoring given the potential risk of developing the generalized form of BP of approximately 15%.3 Topical corticosteroids and oral antibiotics are recommended as the first-line therapy in these patients, with an escalated systemic therapy if needed for disease progression.^3,5

Our case represents an important differential diagnosis to consider when evaluating an acute localized bullous eruption in an elderly patient.

Dr. Cusick and Dr. Dolohanty are with the department of dermatology, University of Rochester (N.Y.), and provided the case and photo. Donna Bilu Martin, MD, edited the column.
 

Dr. Bilu Martin is a board-certified dermatologist in private practice at Premier Dermatology, MD, in Aventura, Fla. More diagnostic cases are available at mdedge.com/dermatology. To submit a case for possible publication, send an email to [email protected].

References

1. Kohroh K et al. J Dermatol. 2007 Jul;34(7):482-5.

2. Nguyen T et al. Dermatology 2014;229(2):88-96.

3. Sen BB et al. Indian J Dermatol Venereol Leprol. 2013;79(4):554.

4. Salomon RJ et al. Arch Dermatol. 1987 Mar;123(3):389-92.

5. Tran JT, Mutasim DF. Int J Dermatol. 2005 Nov;44(11):942-5.

Localized bullous pemphigoid

Bullous pemphigoid is a systemic, autoimmune bullous disease that classically presents as widespread urticarial plaques or tense bullae with a predilection in the elderly population.¹

Localized variants of bullous pemphigoid (BP) are rare and have been reported to arise at sites of mechanical trauma, prior radiation, lymphedema, surgical scars, burns, fistulas, and ostomies.^1-3 Although the mechanism remains unclear, the Koebner phenomenon is thought to induce dysregulation of immunologic and vascular factors in sites of mechanical shear and trauma in susceptible individuals.³

Localized BP is an important entity for the dermatologist to be familiar with, as the diagnosis is often delayed. The localized, well-defined skin lesions frequently mimic contact dermatitis. In fact, previous reports have shown the most likely misdiagnosis of localized BP is acute allergic contact dermatitis, stasis dermatitis, and eczematous dermatitis.^4,5

In this patient, histopathologic examination of a biopsy revealed a subepidermal blister with numerous eosinophils. Direct immunofluorescence study of perilesional skin showed strong linear IgG and C3 deposits at the basal membrane level. Serum level of autoantibody to BP180 antigen was elevated. Bacterial culture was positive for Staphylococcus aureus. These findings were suggestive of unilateral, localized BP with superimposed bacterial infection. Initial treatment with an extended course of doxycycline 200 mg twice daily, topical triamcinolone 0.1% ointment twice daily with compression therapy, and leg elevation led to clinical improvement with healing of previous lesions on the leg. At follow-up 3 weeks later, the patient had continued to develop new bullous lesions on the trunk and upper thighs. He was subsequently started on systemic immunosuppressive therapy for generalized bullous pemphigoid.

Importantly, localized BP generally follows a more benign disease course, although long-term follow-up is recommended for monitoring given the potential risk of developing the generalized form of BP of approximately 15%.3 Topical corticosteroids and oral antibiotics are recommended as the first-line therapy in these patients, with an escalated systemic therapy if needed for disease progression.^3,5

Our case represents an important differential diagnosis to consider when evaluating an acute localized bullous eruption in an elderly patient.

Dr. Cusick and Dr. Dolohanty are with the department of dermatology, University of Rochester (N.Y.), and provided the case and photo. Donna Bilu Martin, MD, edited the column.
 

Dr. Bilu Martin is a board-certified dermatologist in private practice at Premier Dermatology, MD, in Aventura, Fla. More diagnostic cases are available at mdedge.com/dermatology. To submit a case for possible publication, send an email to [email protected].

References

1. Kohroh K et al. J Dermatol. 2007 Jul;34(7):482-5.

2. Nguyen T et al. Dermatology 2014;229(2):88-96.

3. Sen BB et al. Indian J Dermatol Venereol Leprol. 2013;79(4):554.

4. Salomon RJ et al. Arch Dermatol. 1987 Mar;123(3):389-92.

5. Tran JT, Mutasim DF. Int J Dermatol. 2005 Nov;44(11):942-5.

Localized bullous pemphigoid

Bullous pemphigoid is a systemic, autoimmune bullous disease that classically presents as widespread urticarial plaques or tense bullae with a predilection in the elderly population.¹

Localized variants of bullous pemphigoid (BP) are rare and have been reported to arise at sites of mechanical trauma, prior radiation, lymphedema, surgical scars, burns, fistulas, and ostomies.^1-3 Although the mechanism remains unclear, the Koebner phenomenon is thought to induce dysregulation of immunologic and vascular factors in sites of mechanical shear and trauma in susceptible individuals.³

Localized BP is an important entity for the dermatologist to be familiar with, as the diagnosis is often delayed. The localized, well-defined skin lesions frequently mimic contact dermatitis. In fact, previous reports have shown the most likely misdiagnosis of localized BP is acute allergic contact dermatitis, stasis dermatitis, and eczematous dermatitis.^4,5

In this patient, histopathologic examination of a biopsy revealed a subepidermal blister with numerous eosinophils. Direct immunofluorescence study of perilesional skin showed strong linear IgG and C3 deposits at the basal membrane level. Serum level of autoantibody to BP180 antigen was elevated. Bacterial culture was positive for Staphylococcus aureus. These findings were suggestive of unilateral, localized BP with superimposed bacterial infection. Initial treatment with an extended course of doxycycline 200 mg twice daily, topical triamcinolone 0.1% ointment twice daily with compression therapy, and leg elevation led to clinical improvement with healing of previous lesions on the leg. At follow-up 3 weeks later, the patient had continued to develop new bullous lesions on the trunk and upper thighs. He was subsequently started on systemic immunosuppressive therapy for generalized bullous pemphigoid.

Importantly, localized BP generally follows a more benign disease course, although long-term follow-up is recommended for monitoring given the potential risk of developing the generalized form of BP of approximately 15%.3 Topical corticosteroids and oral antibiotics are recommended as the first-line therapy in these patients, with an escalated systemic therapy if needed for disease progression.^3,5

Our case represents an important differential diagnosis to consider when evaluating an acute localized bullous eruption in an elderly patient.

Dr. Cusick and Dr. Dolohanty are with the department of dermatology, University of Rochester (N.Y.), and provided the case and photo. Donna Bilu Martin, MD, edited the column.
 

Dr. Bilu Martin is a board-certified dermatologist in private practice at Premier Dermatology, MD, in Aventura, Fla. More diagnostic cases are available at mdedge.com/dermatology. To submit a case for possible publication, send an email to [email protected].

References

1. Kohroh K et al. J Dermatol. 2007 Jul;34(7):482-5.

2. Nguyen T et al. Dermatology 2014;229(2):88-96.

3. Sen BB et al. Indian J Dermatol Venereol Leprol. 2013;79(4):554.

4. Salomon RJ et al. Arch Dermatol. 1987 Mar;123(3):389-92.

5. Tran JT, Mutasim DF. Int J Dermatol. 2005 Nov;44(11):942-5.

The Diagnosis: Annular Psoriasis

Because the patient's history was nonconcordant with the clinical appearance, a 4-mm punch biopsy was performed from a lesion on the left hip. Hematoxylin and eosin-stained sections demonstrated mild irregular acanthosis of the epidermis with discrete mounds of parakeratin (Figure 1A). Higher power revealed numerous neutrophils entrapped within focal scale crusts (Figure 1B). Periodic acid-Schiff stain for fungus demonstrated no hyphal elements or yeast forms in the stratum corneum. These histopathology findings were consistent with the diagnosis of annular psoriasis.

The manifestation of psoriasis may take many forms, ranging from classic plaques to pustular eruptions--either annular or generalized--and erythroderma. Primarily annular plaque-type psoriasis without pustules, however, remains an uncommon finding.¹ Psoriatic plaques may become annular or arcuate with central clearing from partial treatment with topical medications, though our patient reported annular plaques prior to any treatment. His presentation was notably different than annular pustular psoriasis in that there were no pustules in the leading edge, and there was no trailing scale, which is typical of annular pustular psoriasis.

Topical triamcinolone prescribed at the initial presentation to the dermatology department helped with pruritus, but due to the large body surface area involved, methotrexate later was initiated. After a 10-mg test dose of methotrexate and titration to 15 mg weekly, dramatic improvement in the rash was noted after 8 weeks. As the rash resolved, only faint hyperpigmented patches remained (Figure 2).

Erythema gyratum repens is a rare paraneoplastic syndrome that presents with annular scaly plaques with concentric circles with a wood grain-like appearance. The borders can advance up to 1 cm daily and show nonspecific findings on histopathology.² Due to the observation that approximately 80% of cases of erythema gyratum repens were associated with an underlying malignancy, most often of the lung,³ this diagnosis was entertained given our patient's clinical presentation.

Erythema annulare centrifugum (EAC) historically has been divided into 2 forms: superficial and deep.⁴ Both present with slowly expanding, annular, pink plaques. Superficial EAC demonstrates parakeratosis and trailing scale and has not been proven to be associated with other systemic diseases, while deep EAC has infiltrated borders without scale, and many cases of EAC may represent annular forms of tumid lupus.⁴ Inflammatory cells may cuff vessels tightly, resulting in so-called coat sleeve infiltrate in superficial EAC. Along with trailing scale, this finding suggests the diagnosis. It has been argued that EAC is not an entity on its own and should prompt evaluation for lupus erythematosus, dermatitis, hypersensitivity to tinea pedis, and Lyme disease in appropriate circumstances.⁵

Tinea corporis always should be considered when evaluating annular scaly plaques with central clearing. Diagnosis and treatment are straightforward when hyphae are found on microscopy of skin scrapings or seen on periodic acid-Schiff stains of formalin-fixed tissue. Tinea imbricata presents with an interesting morphology and appears more ornate or cerebriform than tinea corporis caused by Trichophyton rubrum. It is caused by infection with Trichophyton circumscriptum and occurs in certain regions in the South Pacific, Southeast Asia, and Central and South America, making the diagnosis within the United States unlikely for a patient who has not traveled to these areas.⁶

Erythema chronicum migrans is diagnostic of Lyme disease infection with Borrelia burgdorferi, and solitary lesions occur surrounding the site of a tick bite in the majority of patients. Only 20% of patients will develop multiple lesions consistent with erythema chronicum migrans due to multiple tick bites, spirochetemia, or lymphatic spread.⁷ Up to one-third of patients are unaware that they were bitten by a tick. In endemic areas, this diagnosis must be entertained in any patient presenting with an annular rash, as treatment may prevent notable morbidity.

The Diagnosis: Annular Psoriasis

Because the patient's history was nonconcordant with the clinical appearance, a 4-mm punch biopsy was performed from a lesion on the left hip. Hematoxylin and eosin-stained sections demonstrated mild irregular acanthosis of the epidermis with discrete mounds of parakeratin (Figure 1A). Higher power revealed numerous neutrophils entrapped within focal scale crusts (Figure 1B). Periodic acid-Schiff stain for fungus demonstrated no hyphal elements or yeast forms in the stratum corneum. These histopathology findings were consistent with the diagnosis of annular psoriasis.

The manifestation of psoriasis may take many forms, ranging from classic plaques to pustular eruptions--either annular or generalized--and erythroderma. Primarily annular plaque-type psoriasis without pustules, however, remains an uncommon finding.¹ Psoriatic plaques may become annular or arcuate with central clearing from partial treatment with topical medications, though our patient reported annular plaques prior to any treatment. His presentation was notably different than annular pustular psoriasis in that there were no pustules in the leading edge, and there was no trailing scale, which is typical of annular pustular psoriasis.

Topical triamcinolone prescribed at the initial presentation to the dermatology department helped with pruritus, but due to the large body surface area involved, methotrexate later was initiated. After a 10-mg test dose of methotrexate and titration to 15 mg weekly, dramatic improvement in the rash was noted after 8 weeks. As the rash resolved, only faint hyperpigmented patches remained (Figure 2).

Erythema gyratum repens is a rare paraneoplastic syndrome that presents with annular scaly plaques with concentric circles with a wood grain-like appearance. The borders can advance up to 1 cm daily and show nonspecific findings on histopathology.² Due to the observation that approximately 80% of cases of erythema gyratum repens were associated with an underlying malignancy, most often of the lung,³ this diagnosis was entertained given our patient's clinical presentation.

Erythema annulare centrifugum (EAC) historically has been divided into 2 forms: superficial and deep.⁴ Both present with slowly expanding, annular, pink plaques. Superficial EAC demonstrates parakeratosis and trailing scale and has not been proven to be associated with other systemic diseases, while deep EAC has infiltrated borders without scale, and many cases of EAC may represent annular forms of tumid lupus.⁴ Inflammatory cells may cuff vessels tightly, resulting in so-called coat sleeve infiltrate in superficial EAC. Along with trailing scale, this finding suggests the diagnosis. It has been argued that EAC is not an entity on its own and should prompt evaluation for lupus erythematosus, dermatitis, hypersensitivity to tinea pedis, and Lyme disease in appropriate circumstances.⁵

Tinea corporis always should be considered when evaluating annular scaly plaques with central clearing. Diagnosis and treatment are straightforward when hyphae are found on microscopy of skin scrapings or seen on periodic acid-Schiff stains of formalin-fixed tissue. Tinea imbricata presents with an interesting morphology and appears more ornate or cerebriform than tinea corporis caused by Trichophyton rubrum. It is caused by infection with Trichophyton circumscriptum and occurs in certain regions in the South Pacific, Southeast Asia, and Central and South America, making the diagnosis within the United States unlikely for a patient who has not traveled to these areas.⁶

Erythema chronicum migrans is diagnostic of Lyme disease infection with Borrelia burgdorferi, and solitary lesions occur surrounding the site of a tick bite in the majority of patients. Only 20% of patients will develop multiple lesions consistent with erythema chronicum migrans due to multiple tick bites, spirochetemia, or lymphatic spread.⁷ Up to one-third of patients are unaware that they were bitten by a tick. In endemic areas, this diagnosis must be entertained in any patient presenting with an annular rash, as treatment may prevent notable morbidity.

The Diagnosis: Annular Psoriasis

Because the patient's history was nonconcordant with the clinical appearance, a 4-mm punch biopsy was performed from a lesion on the left hip. Hematoxylin and eosin-stained sections demonstrated mild irregular acanthosis of the epidermis with discrete mounds of parakeratin (Figure 1A). Higher power revealed numerous neutrophils entrapped within focal scale crusts (Figure 1B). Periodic acid-Schiff stain for fungus demonstrated no hyphal elements or yeast forms in the stratum corneum. These histopathology findings were consistent with the diagnosis of annular psoriasis.

The manifestation of psoriasis may take many forms, ranging from classic plaques to pustular eruptions--either annular or generalized--and erythroderma. Primarily annular plaque-type psoriasis without pustules, however, remains an uncommon finding.¹ Psoriatic plaques may become annular or arcuate with central clearing from partial treatment with topical medications, though our patient reported annular plaques prior to any treatment. His presentation was notably different than annular pustular psoriasis in that there were no pustules in the leading edge, and there was no trailing scale, which is typical of annular pustular psoriasis.

Topical triamcinolone prescribed at the initial presentation to the dermatology department helped with pruritus, but due to the large body surface area involved, methotrexate later was initiated. After a 10-mg test dose of methotrexate and titration to 15 mg weekly, dramatic improvement in the rash was noted after 8 weeks. As the rash resolved, only faint hyperpigmented patches remained (Figure 2).

Erythema gyratum repens is a rare paraneoplastic syndrome that presents with annular scaly plaques with concentric circles with a wood grain-like appearance. The borders can advance up to 1 cm daily and show nonspecific findings on histopathology.² Due to the observation that approximately 80% of cases of erythema gyratum repens were associated with an underlying malignancy, most often of the lung,³ this diagnosis was entertained given our patient's clinical presentation.

Erythema annulare centrifugum (EAC) historically has been divided into 2 forms: superficial and deep.⁴ Both present with slowly expanding, annular, pink plaques. Superficial EAC demonstrates parakeratosis and trailing scale and has not been proven to be associated with other systemic diseases, while deep EAC has infiltrated borders without scale, and many cases of EAC may represent annular forms of tumid lupus.⁴ Inflammatory cells may cuff vessels tightly, resulting in so-called coat sleeve infiltrate in superficial EAC. Along with trailing scale, this finding suggests the diagnosis. It has been argued that EAC is not an entity on its own and should prompt evaluation for lupus erythematosus, dermatitis, hypersensitivity to tinea pedis, and Lyme disease in appropriate circumstances.⁵

Tinea corporis always should be considered when evaluating annular scaly plaques with central clearing. Diagnosis and treatment are straightforward when hyphae are found on microscopy of skin scrapings or seen on periodic acid-Schiff stains of formalin-fixed tissue. Tinea imbricata presents with an interesting morphology and appears more ornate or cerebriform than tinea corporis caused by Trichophyton rubrum. It is caused by infection with Trichophyton circumscriptum and occurs in certain regions in the South Pacific, Southeast Asia, and Central and South America, making the diagnosis within the United States unlikely for a patient who has not traveled to these areas.⁶

Erythema chronicum migrans is diagnostic of Lyme disease infection with Borrelia burgdorferi, and solitary lesions occur surrounding the site of a tick bite in the majority of patients. Only 20% of patients will develop multiple lesions consistent with erythema chronicum migrans due to multiple tick bites, spirochetemia, or lymphatic spread.⁷ Up to one-third of patients are unaware that they were bitten by a tick. In endemic areas, this diagnosis must be entertained in any patient presenting with an annular rash, as treatment may prevent notable morbidity.