Niraj Butala, MD

Cutaneous amyloidosis encompasses a variety of clinical presentations. Primary localized cutaneous amyloidosis comprises lichen amyloidosis, macular amyloidosis, and nodular amyloidosis.¹ Macular and lichen amyloidosis result from keratin deposits, while nodular amyloidosis results from cutaneous infiltration of plasma cells.² Primary systemic amyloidosis is due to a plasma cell dyscrasia, particularly multiple myeloma, while secondary systemic amyloidosis occurs in the setting of restrictive cardiomyopathy, congestive heart failure, renal dysfunction, or chronic inflammation, as seen with rheumatoid arthritis, tuberculosis, and various autoinflammatory disorders.² Plasma cell proliferative disorders are associated with various skin disorders, which may result from aggregated misfolded monoclonal immunoglobulins, indicating light chain–related systemic amyloidosis. Mucocutaneous lesions can occur in 30% to 40% of cases of primary systemic amyloidosis and may present as purpura, ecchymoses, waxy thickening, plaques, subcutaneous nodules, and/or bullae.^3,4 When blistering is present, the differential diagnosis is broad and includes autoimmune bullous disease, drug eruptions, enoxaparin-induced bullous hemorrhagic dermatosis, deposition diseases, allergic contact dermatitis, bullous cellulitis, bullous bite reactions, neutrophilic dermatosis, and bullous lichen sclerosus.⁵ Herein, we present a case of a woman with a bullous skin eruption who eventually was diagnosed with bullous amyloidosis subsequent to a diagnosis of multiple myeloma.

Case Report

A 70-year-old woman presented to our dermatology clinic for evaluation of well-demarcated, hemorrhagic, flaccid vesicles and focal erosions with a rim of erythema on the distal forearms and hands. A shave biopsy from the right forearm showed cell-poor subepidermal vesicular dermatitis. Enzyme-linked immunosorbent assays for bullous pemphigoid antigens 1 and 2 as well as urinary porphyrins were negative. Direct immunofluorescence showed granular IgM at the basement membrane zone around vessels and cytoid bodies. At this time, a preliminary diagnosis of pseudoporphyria was suspected, though no classic medications (eg, nonsteroidal anti-inflammatory drugs, furosemide, antibiotics) or exogenous trigger factors (eg, UV light exposure, dialysis) were temporally related. Three months later, the patient presented with a large hemorrhagic bulla on the distal left forearm (Figure 1) and healing erosions on the dorsal fingers and upper back. Clobetasol ointment was initiated, as an autoimmune bullous dermatosis was suspected.

Approximately 1 year after she was first seen in our outpatient clinic, the patient was hospitalized for induction of chemotherapy—cyclophosphamide, bortezomib, and dexamethasone—for a new diagnosis of stage III multiple myeloma. A workup for back pain revealed multiple compression fractures and a plasma cell neoplasm with elevated λ light chains, which was confirmed with a bone marrow biopsy. During an inpatient dermatology consultation, we noted the development of intraoral hemorrhagic vesicles and worsening generalization of the hemorrhagic bullae, with healing erosions and intact hemorrhagic bullae on the dorsal hands, fingers (Figure 2), and upper back.

A repeat biopsy displayed bullous amyloidosis. Histopathologic examination revealed an ulcerated subepidermal blister with fibrin deposition at the ulcer base. A periadnexal, scant, eosinophilic deposition with extravasated red blood cells was appreciated. Amorphous eosinophilic deposits were found within the detached fragment of the epidermis and inflammatory infiltrate. A Congo red stain highlighted these areas with a salmon pink–colored material. Congo red staining showed a moderate amount of pale, apple green, birefringent deposit within these areas on polarized light examination.

A few months later, the patient was re-admitted, and the amount of skin detachment prompted the primary team to ask for another consultation. Although the extensive skin sloughing resembled toxic epidermal necrolysis, a repeat biopsy confirmed bullous amyloidosis.

Comment

Amyloidosis Histopathology—Amyloidoses represent a wide array of disorders with deposition of β-pleated sheets or amyloid fibrils, often with cutaneous manifestations.^2,3 Primary systemic amyloidosis has been associated with underlying dyscrasia or multiple myeloma.⁶ In such cases, the skin lesions of multiple myeloma may result from a collection of misfolded monoclonal immunoglobulins or their fragments, as in light chain–related systemic amyloidosis.³ Histopathologically, both systemic and cutaneous amyloidosis appear similar and display deposition of amorphous, eosinophilic, fissured amyloid material in the dermis. Congo red stains the material orange-red and will display a characteristic apple green birefringence under polarized light.⁴ Although bullous amyloid lesions are rare, the cutaneous forms of these lesions can be an important sign of plasma cell dyscrasia.⁷

Presentation of Bullous Amyloidosis—Bullous manifestations rarely have been noted in the primary cutaneous forms of amyloidosis.^5,8,9 Importantly, cutaneous blistering more often is linked to systemic forms of amyloidosis with multiorgan involvement, including primary systemic and myeloma-associated amyloidosis.^5,10 However, patients with localized bullous cutaneous amyloidosis without systemic involvement also have been seen.^10,11 Bullae may occur at any time, with contents that frequently are hemorrhagic due to capillary fragility.^12,13 Bullous manifestations raise the differential diagnoses of bullous pemphigoid, epidermolysis bullosa acquisita, linear IgA disease, porphyria cutanea tarda, pseudoporphyria, bullous drug eruption, bullous eruption of renal dialysis, or bullous lupus erythematosus.^5,13-17

In our patient, the acral distribution of bullae, presence of hemorrhage, chronicity of symptoms, and negative enzyme-linked immunosorbent assay initially suggested a diagnosis of pseudoporphyria. However, the presence of intraoral hemorrhagic vesicles and subsequent confirmatory pathology aided in differentiating bullous amyloidosis from pseudoporphyria. Nodular localized primary cutaneous amyloidosis, a rare form of skin-restricted amyloidoses, can coexist with bullous lesions. Of note, reported cases of nodular localized primary cutaneous amyloidosis did not result in development of multiple myeloma.^5,10

Bullae are located either subepidermally or intradermally, and bullous lesions of cutaneous amyloidosis typically demonstrate subepidermal or superficial intradermal clefting on light microscopy.^5,10,12 Histopathology of bullous amyloidosis shows intradermal or subepidermal blister formation and amorphous eosinophilic material showing apple green birefringence with Congo red staining deposited in the dermis and/or around the adipocytes and blood vessel walls.^12,18-20 In prior cases, direct immunofluorescence of bullous amyloidosis revealed absent immunoglobulin (IgG, IgA, IgM) or complement (C3 and C9) deposits in the basement membrane zone or dermis.^13,21,22 In these cases, electron microscopy was useful in diagnosis, as it showed the presence of amyloid deposits.^21,22

Cause of Bullae—Various mechanisms are thought to trigger the blister formation in amyloidosis. Bullae created from trauma or friction often present as tense painful blisters that commonly are hemorrhagic.^10,23 Amyloid deposits in the walls of blood vessels and the affinity of dermal amyloid in blood vessel walls to surrounding collagen likely leads to increased fragility of capillaries and the dermal matrix, hemorrhagic tendency, and infrapapillary blisters, thus creating hemorrhagic bullous eruptions.^24,25 Specifically, close proximity of immunoglobulin-derived amyloid oligomers to epidermal keratinocytes may be toxic and therefore could trigger subepidermal bullous change.⁵ Additionally, alteration in the physicochemical properties of the amyloidal protein might explain bullous eruption.⁹ Trauma or rubbing of the hands and feet may precipitate the acral blister formation in bullous amyloidosis.^5,11

Due to deposition of these amyloid fibrils, skin bleeding in these patients is called amyloid or pinch purpura. Vessel wall fragility and damage by amyloid are the principal causes of periorbital and gastrointestinal tract bleeding.²⁶ Destruction of the lamina densa and widening of the intercellular space between keratinocytes by amyloid globules induce skin fragility.¹¹

Although uncommon, various cases of bullous amyloidosis have been reported in the literature. Multiple myeloma patients represent the majority of those reported to have bullous amyloidosis.^{6,7,13,24,27-30} Plasmacytoma-associated bullous amyloid purpura and paraproteinemia also have been noted.²⁵ Multiple myeloma with secondary AL amyloidosis has been seen with amyloid purpura and atraumatic ecchymoses of the face, highlighting the hemorrhage noted in these patients.²⁶

Management of Amyloidosis—Various treatment options have been attempted for primary cutaneous amyloidosis, including oral retinoids, corticosteroids, cyclophosphamide, cyclosporine, amitriptyline, colchicine, cepharanthin, tacrolimus, dimethyl sulfoxide, vitamin D₃ analogs, capsaicin, menthol, hydrocolloid dressings, surgical modalities, laser treatment, and phototherapy.¹ There is no clear consensus for therapeutic modalities except for treating the underlying plasma cell dyscrasia in primary systemic amyloidosis.

Conclusion

We report the case of a patient displaying signs of pseudoporphyria that ultimately proved to be bullous amyloidosis, or what we termed pseudopseudoporphyria. Bullous amyloidosis should be considered in the differential diagnoses of hemorrhagic bullous skin eruptions. Particular attention should be given to a systemic workup for multiple myeloma when hemorrhagic vesicles/bullae are chronic and coexist with purpura, angina bullosa hemorrhagica, fatigue/weight loss, and/or macroglossia.

Cutaneous amyloidosis encompasses a variety of clinical presentations. Primary localized cutaneous amyloidosis comprises lichen amyloidosis, macular amyloidosis, and nodular amyloidosis.¹ Macular and lichen amyloidosis result from keratin deposits, while nodular amyloidosis results from cutaneous infiltration of plasma cells.² Primary systemic amyloidosis is due to a plasma cell dyscrasia, particularly multiple myeloma, while secondary systemic amyloidosis occurs in the setting of restrictive cardiomyopathy, congestive heart failure, renal dysfunction, or chronic inflammation, as seen with rheumatoid arthritis, tuberculosis, and various autoinflammatory disorders.² Plasma cell proliferative disorders are associated with various skin disorders, which may result from aggregated misfolded monoclonal immunoglobulins, indicating light chain–related systemic amyloidosis. Mucocutaneous lesions can occur in 30% to 40% of cases of primary systemic amyloidosis and may present as purpura, ecchymoses, waxy thickening, plaques, subcutaneous nodules, and/or bullae.^3,4 When blistering is present, the differential diagnosis is broad and includes autoimmune bullous disease, drug eruptions, enoxaparin-induced bullous hemorrhagic dermatosis, deposition diseases, allergic contact dermatitis, bullous cellulitis, bullous bite reactions, neutrophilic dermatosis, and bullous lichen sclerosus.⁵ Herein, we present a case of a woman with a bullous skin eruption who eventually was diagnosed with bullous amyloidosis subsequent to a diagnosis of multiple myeloma.

Case Report

A 70-year-old woman presented to our dermatology clinic for evaluation of well-demarcated, hemorrhagic, flaccid vesicles and focal erosions with a rim of erythema on the distal forearms and hands. A shave biopsy from the right forearm showed cell-poor subepidermal vesicular dermatitis. Enzyme-linked immunosorbent assays for bullous pemphigoid antigens 1 and 2 as well as urinary porphyrins were negative. Direct immunofluorescence showed granular IgM at the basement membrane zone around vessels and cytoid bodies. At this time, a preliminary diagnosis of pseudoporphyria was suspected, though no classic medications (eg, nonsteroidal anti-inflammatory drugs, furosemide, antibiotics) or exogenous trigger factors (eg, UV light exposure, dialysis) were temporally related. Three months later, the patient presented with a large hemorrhagic bulla on the distal left forearm (Figure 1) and healing erosions on the dorsal fingers and upper back. Clobetasol ointment was initiated, as an autoimmune bullous dermatosis was suspected.

Approximately 1 year after she was first seen in our outpatient clinic, the patient was hospitalized for induction of chemotherapy—cyclophosphamide, bortezomib, and dexamethasone—for a new diagnosis of stage III multiple myeloma. A workup for back pain revealed multiple compression fractures and a plasma cell neoplasm with elevated λ light chains, which was confirmed with a bone marrow biopsy. During an inpatient dermatology consultation, we noted the development of intraoral hemorrhagic vesicles and worsening generalization of the hemorrhagic bullae, with healing erosions and intact hemorrhagic bullae on the dorsal hands, fingers (Figure 2), and upper back.

A repeat biopsy displayed bullous amyloidosis. Histopathologic examination revealed an ulcerated subepidermal blister with fibrin deposition at the ulcer base. A periadnexal, scant, eosinophilic deposition with extravasated red blood cells was appreciated. Amorphous eosinophilic deposits were found within the detached fragment of the epidermis and inflammatory infiltrate. A Congo red stain highlighted these areas with a salmon pink–colored material. Congo red staining showed a moderate amount of pale, apple green, birefringent deposit within these areas on polarized light examination.

A few months later, the patient was re-admitted, and the amount of skin detachment prompted the primary team to ask for another consultation. Although the extensive skin sloughing resembled toxic epidermal necrolysis, a repeat biopsy confirmed bullous amyloidosis.

Comment

Amyloidosis Histopathology—Amyloidoses represent a wide array of disorders with deposition of β-pleated sheets or amyloid fibrils, often with cutaneous manifestations.^2,3 Primary systemic amyloidosis has been associated with underlying dyscrasia or multiple myeloma.⁶ In such cases, the skin lesions of multiple myeloma may result from a collection of misfolded monoclonal immunoglobulins or their fragments, as in light chain–related systemic amyloidosis.³ Histopathologically, both systemic and cutaneous amyloidosis appear similar and display deposition of amorphous, eosinophilic, fissured amyloid material in the dermis. Congo red stains the material orange-red and will display a characteristic apple green birefringence under polarized light.⁴ Although bullous amyloid lesions are rare, the cutaneous forms of these lesions can be an important sign of plasma cell dyscrasia.⁷

Presentation of Bullous Amyloidosis—Bullous manifestations rarely have been noted in the primary cutaneous forms of amyloidosis.^5,8,9 Importantly, cutaneous blistering more often is linked to systemic forms of amyloidosis with multiorgan involvement, including primary systemic and myeloma-associated amyloidosis.^5,10 However, patients with localized bullous cutaneous amyloidosis without systemic involvement also have been seen.^10,11 Bullae may occur at any time, with contents that frequently are hemorrhagic due to capillary fragility.^12,13 Bullous manifestations raise the differential diagnoses of bullous pemphigoid, epidermolysis bullosa acquisita, linear IgA disease, porphyria cutanea tarda, pseudoporphyria, bullous drug eruption, bullous eruption of renal dialysis, or bullous lupus erythematosus.^5,13-17

In our patient, the acral distribution of bullae, presence of hemorrhage, chronicity of symptoms, and negative enzyme-linked immunosorbent assay initially suggested a diagnosis of pseudoporphyria. However, the presence of intraoral hemorrhagic vesicles and subsequent confirmatory pathology aided in differentiating bullous amyloidosis from pseudoporphyria. Nodular localized primary cutaneous amyloidosis, a rare form of skin-restricted amyloidoses, can coexist with bullous lesions. Of note, reported cases of nodular localized primary cutaneous amyloidosis did not result in development of multiple myeloma.^5,10

Bullae are located either subepidermally or intradermally, and bullous lesions of cutaneous amyloidosis typically demonstrate subepidermal or superficial intradermal clefting on light microscopy.^5,10,12 Histopathology of bullous amyloidosis shows intradermal or subepidermal blister formation and amorphous eosinophilic material showing apple green birefringence with Congo red staining deposited in the dermis and/or around the adipocytes and blood vessel walls.^12,18-20 In prior cases, direct immunofluorescence of bullous amyloidosis revealed absent immunoglobulin (IgG, IgA, IgM) or complement (C3 and C9) deposits in the basement membrane zone or dermis.^13,21,22 In these cases, electron microscopy was useful in diagnosis, as it showed the presence of amyloid deposits.^21,22

Cause of Bullae—Various mechanisms are thought to trigger the blister formation in amyloidosis. Bullae created from trauma or friction often present as tense painful blisters that commonly are hemorrhagic.^10,23 Amyloid deposits in the walls of blood vessels and the affinity of dermal amyloid in blood vessel walls to surrounding collagen likely leads to increased fragility of capillaries and the dermal matrix, hemorrhagic tendency, and infrapapillary blisters, thus creating hemorrhagic bullous eruptions.^24,25 Specifically, close proximity of immunoglobulin-derived amyloid oligomers to epidermal keratinocytes may be toxic and therefore could trigger subepidermal bullous change.⁵ Additionally, alteration in the physicochemical properties of the amyloidal protein might explain bullous eruption.⁹ Trauma or rubbing of the hands and feet may precipitate the acral blister formation in bullous amyloidosis.^5,11

Due to deposition of these amyloid fibrils, skin bleeding in these patients is called amyloid or pinch purpura. Vessel wall fragility and damage by amyloid are the principal causes of periorbital and gastrointestinal tract bleeding.²⁶ Destruction of the lamina densa and widening of the intercellular space between keratinocytes by amyloid globules induce skin fragility.¹¹

Although uncommon, various cases of bullous amyloidosis have been reported in the literature. Multiple myeloma patients represent the majority of those reported to have bullous amyloidosis.^{6,7,13,24,27-30} Plasmacytoma-associated bullous amyloid purpura and paraproteinemia also have been noted.²⁵ Multiple myeloma with secondary AL amyloidosis has been seen with amyloid purpura and atraumatic ecchymoses of the face, highlighting the hemorrhage noted in these patients.²⁶

Management of Amyloidosis—Various treatment options have been attempted for primary cutaneous amyloidosis, including oral retinoids, corticosteroids, cyclophosphamide, cyclosporine, amitriptyline, colchicine, cepharanthin, tacrolimus, dimethyl sulfoxide, vitamin D₃ analogs, capsaicin, menthol, hydrocolloid dressings, surgical modalities, laser treatment, and phototherapy.¹ There is no clear consensus for therapeutic modalities except for treating the underlying plasma cell dyscrasia in primary systemic amyloidosis.

Conclusion

We report the case of a patient displaying signs of pseudoporphyria that ultimately proved to be bullous amyloidosis, or what we termed pseudopseudoporphyria. Bullous amyloidosis should be considered in the differential diagnoses of hemorrhagic bullous skin eruptions. Particular attention should be given to a systemic workup for multiple myeloma when hemorrhagic vesicles/bullae are chronic and coexist with purpura, angina bullosa hemorrhagica, fatigue/weight loss, and/or macroglossia.

Cutaneous amyloidosis encompasses a variety of clinical presentations. Primary localized cutaneous amyloidosis comprises lichen amyloidosis, macular amyloidosis, and nodular amyloidosis.¹ Macular and lichen amyloidosis result from keratin deposits, while nodular amyloidosis results from cutaneous infiltration of plasma cells.² Primary systemic amyloidosis is due to a plasma cell dyscrasia, particularly multiple myeloma, while secondary systemic amyloidosis occurs in the setting of restrictive cardiomyopathy, congestive heart failure, renal dysfunction, or chronic inflammation, as seen with rheumatoid arthritis, tuberculosis, and various autoinflammatory disorders.² Plasma cell proliferative disorders are associated with various skin disorders, which may result from aggregated misfolded monoclonal immunoglobulins, indicating light chain–related systemic amyloidosis. Mucocutaneous lesions can occur in 30% to 40% of cases of primary systemic amyloidosis and may present as purpura, ecchymoses, waxy thickening, plaques, subcutaneous nodules, and/or bullae.^3,4 When blistering is present, the differential diagnosis is broad and includes autoimmune bullous disease, drug eruptions, enoxaparin-induced bullous hemorrhagic dermatosis, deposition diseases, allergic contact dermatitis, bullous cellulitis, bullous bite reactions, neutrophilic dermatosis, and bullous lichen sclerosus.⁵ Herein, we present a case of a woman with a bullous skin eruption who eventually was diagnosed with bullous amyloidosis subsequent to a diagnosis of multiple myeloma.

Case Report

A 70-year-old woman presented to our dermatology clinic for evaluation of well-demarcated, hemorrhagic, flaccid vesicles and focal erosions with a rim of erythema on the distal forearms and hands. A shave biopsy from the right forearm showed cell-poor subepidermal vesicular dermatitis. Enzyme-linked immunosorbent assays for bullous pemphigoid antigens 1 and 2 as well as urinary porphyrins were negative. Direct immunofluorescence showed granular IgM at the basement membrane zone around vessels and cytoid bodies. At this time, a preliminary diagnosis of pseudoporphyria was suspected, though no classic medications (eg, nonsteroidal anti-inflammatory drugs, furosemide, antibiotics) or exogenous trigger factors (eg, UV light exposure, dialysis) were temporally related. Three months later, the patient presented with a large hemorrhagic bulla on the distal left forearm (Figure 1) and healing erosions on the dorsal fingers and upper back. Clobetasol ointment was initiated, as an autoimmune bullous dermatosis was suspected.

Approximately 1 year after she was first seen in our outpatient clinic, the patient was hospitalized for induction of chemotherapy—cyclophosphamide, bortezomib, and dexamethasone—for a new diagnosis of stage III multiple myeloma. A workup for back pain revealed multiple compression fractures and a plasma cell neoplasm with elevated λ light chains, which was confirmed with a bone marrow biopsy. During an inpatient dermatology consultation, we noted the development of intraoral hemorrhagic vesicles and worsening generalization of the hemorrhagic bullae, with healing erosions and intact hemorrhagic bullae on the dorsal hands, fingers (Figure 2), and upper back.

A repeat biopsy displayed bullous amyloidosis. Histopathologic examination revealed an ulcerated subepidermal blister with fibrin deposition at the ulcer base. A periadnexal, scant, eosinophilic deposition with extravasated red blood cells was appreciated. Amorphous eosinophilic deposits were found within the detached fragment of the epidermis and inflammatory infiltrate. A Congo red stain highlighted these areas with a salmon pink–colored material. Congo red staining showed a moderate amount of pale, apple green, birefringent deposit within these areas on polarized light examination.

A few months later, the patient was re-admitted, and the amount of skin detachment prompted the primary team to ask for another consultation. Although the extensive skin sloughing resembled toxic epidermal necrolysis, a repeat biopsy confirmed bullous amyloidosis.

Comment

Amyloidosis Histopathology—Amyloidoses represent a wide array of disorders with deposition of β-pleated sheets or amyloid fibrils, often with cutaneous manifestations.^2,3 Primary systemic amyloidosis has been associated with underlying dyscrasia or multiple myeloma.⁶ In such cases, the skin lesions of multiple myeloma may result from a collection of misfolded monoclonal immunoglobulins or their fragments, as in light chain–related systemic amyloidosis.³ Histopathologically, both systemic and cutaneous amyloidosis appear similar and display deposition of amorphous, eosinophilic, fissured amyloid material in the dermis. Congo red stains the material orange-red and will display a characteristic apple green birefringence under polarized light.⁴ Although bullous amyloid lesions are rare, the cutaneous forms of these lesions can be an important sign of plasma cell dyscrasia.⁷

Presentation of Bullous Amyloidosis—Bullous manifestations rarely have been noted in the primary cutaneous forms of amyloidosis.^5,8,9 Importantly, cutaneous blistering more often is linked to systemic forms of amyloidosis with multiorgan involvement, including primary systemic and myeloma-associated amyloidosis.^5,10 However, patients with localized bullous cutaneous amyloidosis without systemic involvement also have been seen.^10,11 Bullae may occur at any time, with contents that frequently are hemorrhagic due to capillary fragility.^12,13 Bullous manifestations raise the differential diagnoses of bullous pemphigoid, epidermolysis bullosa acquisita, linear IgA disease, porphyria cutanea tarda, pseudoporphyria, bullous drug eruption, bullous eruption of renal dialysis, or bullous lupus erythematosus.^5,13-17

In our patient, the acral distribution of bullae, presence of hemorrhage, chronicity of symptoms, and negative enzyme-linked immunosorbent assay initially suggested a diagnosis of pseudoporphyria. However, the presence of intraoral hemorrhagic vesicles and subsequent confirmatory pathology aided in differentiating bullous amyloidosis from pseudoporphyria. Nodular localized primary cutaneous amyloidosis, a rare form of skin-restricted amyloidoses, can coexist with bullous lesions. Of note, reported cases of nodular localized primary cutaneous amyloidosis did not result in development of multiple myeloma.^5,10

Bullae are located either subepidermally or intradermally, and bullous lesions of cutaneous amyloidosis typically demonstrate subepidermal or superficial intradermal clefting on light microscopy.^5,10,12 Histopathology of bullous amyloidosis shows intradermal or subepidermal blister formation and amorphous eosinophilic material showing apple green birefringence with Congo red staining deposited in the dermis and/or around the adipocytes and blood vessel walls.^12,18-20 In prior cases, direct immunofluorescence of bullous amyloidosis revealed absent immunoglobulin (IgG, IgA, IgM) or complement (C3 and C9) deposits in the basement membrane zone or dermis.^13,21,22 In these cases, electron microscopy was useful in diagnosis, as it showed the presence of amyloid deposits.^21,22

Cause of Bullae—Various mechanisms are thought to trigger the blister formation in amyloidosis. Bullae created from trauma or friction often present as tense painful blisters that commonly are hemorrhagic.^10,23 Amyloid deposits in the walls of blood vessels and the affinity of dermal amyloid in blood vessel walls to surrounding collagen likely leads to increased fragility of capillaries and the dermal matrix, hemorrhagic tendency, and infrapapillary blisters, thus creating hemorrhagic bullous eruptions.^24,25 Specifically, close proximity of immunoglobulin-derived amyloid oligomers to epidermal keratinocytes may be toxic and therefore could trigger subepidermal bullous change.⁵ Additionally, alteration in the physicochemical properties of the amyloidal protein might explain bullous eruption.⁹ Trauma or rubbing of the hands and feet may precipitate the acral blister formation in bullous amyloidosis.^5,11

Due to deposition of these amyloid fibrils, skin bleeding in these patients is called amyloid or pinch purpura. Vessel wall fragility and damage by amyloid are the principal causes of periorbital and gastrointestinal tract bleeding.²⁶ Destruction of the lamina densa and widening of the intercellular space between keratinocytes by amyloid globules induce skin fragility.¹¹

Although uncommon, various cases of bullous amyloidosis have been reported in the literature. Multiple myeloma patients represent the majority of those reported to have bullous amyloidosis.^{6,7,13,24,27-30} Plasmacytoma-associated bullous amyloid purpura and paraproteinemia also have been noted.²⁵ Multiple myeloma with secondary AL amyloidosis has been seen with amyloid purpura and atraumatic ecchymoses of the face, highlighting the hemorrhage noted in these patients.²⁶

Management of Amyloidosis—Various treatment options have been attempted for primary cutaneous amyloidosis, including oral retinoids, corticosteroids, cyclophosphamide, cyclosporine, amitriptyline, colchicine, cepharanthin, tacrolimus, dimethyl sulfoxide, vitamin D₃ analogs, capsaicin, menthol, hydrocolloid dressings, surgical modalities, laser treatment, and phototherapy.¹ There is no clear consensus for therapeutic modalities except for treating the underlying plasma cell dyscrasia in primary systemic amyloidosis.

Conclusion

We report the case of a patient displaying signs of pseudoporphyria that ultimately proved to be bullous amyloidosis, or what we termed pseudopseudoporphyria. Bullous amyloidosis should be considered in the differential diagnoses of hemorrhagic bullous skin eruptions. Particular attention should be given to a systemic workup for multiple myeloma when hemorrhagic vesicles/bullae are chronic and coexist with purpura, angina bullosa hemorrhagica, fatigue/weight loss, and/or macroglossia.

To the Editor:

Erythema induratum, also known as nodular vasculitis, is a panniculitis that usually affects the lower extremities in middle-aged women. Classically, it has been described as a delayed-type hypersensitivity reaction to Mycobacterium tuberculosis, also known as a tuberculid.^1,2 Other infections, however, also have been implicated as causes of erythema induratum, including bacillus Calmette-Guérin (BCG), the attenuated form of Mycobacterium bovis, which commonly is used for tuberculosis vaccination. Medications also may cause erythema induratum. The characteristic distribution of the nodules on the posterior calves helps to distinguish erythema induratum from other panniculitides. A PubMed search of articles indexed for MEDLINE using the term disseminated erythema induratum revealed few case reports documenting nodules on the arms, thighs, or chest, and only 1 case report of disseminated erythema induratum.^3-8 We describe a rare combination of disseminated erythema induratum in a patient with remote exposure to tuberculosis and recent BCG exposure.

An 88-year-old woman presented for evaluation of violaceous, minimally tender, nonulcerated, subcutaneous nodules on the legs, arms, and trunk of several weeks’ duration (Figure 1). She had a remote history of tuberculosis as a child, prior to the advent of modern antituberculosis regimens. Her medical history also included hypertension, breast cancer treated with lymph node dissection, gastroesophageal reflux disease, and bladder cancer treated with intravesical BCG 10 years prior to the onset of the nodules. She reported minimal coughing and a 25-lb weight loss over the last year, but she denied night sweats, fever, or chills.

Disseminated erythema induratum, an exceptionally rare variant of panniculitis, may be seen in patients with a remote history of M tuberculosis exposure and/or recent therapeutic BCG exposure. It is imperative to rule out active tuberculosis, especially in elderly patients whose disease predated the advent of modern antituberculosis therapy. Using an IFN-γ release assay in addition to chest radiographs and other clinical stigmata allows differentiation of the etiology of erythema induratum in those patients with tuberculosis who also were treated with BCG.

To the Editor:

Erythema induratum, also known as nodular vasculitis, is a panniculitis that usually affects the lower extremities in middle-aged women. Classically, it has been described as a delayed-type hypersensitivity reaction to Mycobacterium tuberculosis, also known as a tuberculid.^1,2 Other infections, however, also have been implicated as causes of erythema induratum, including bacillus Calmette-Guérin (BCG), the attenuated form of Mycobacterium bovis, which commonly is used for tuberculosis vaccination. Medications also may cause erythema induratum. The characteristic distribution of the nodules on the posterior calves helps to distinguish erythema induratum from other panniculitides. A PubMed search of articles indexed for MEDLINE using the term disseminated erythema induratum revealed few case reports documenting nodules on the arms, thighs, or chest, and only 1 case report of disseminated erythema induratum.^3-8 We describe a rare combination of disseminated erythema induratum in a patient with remote exposure to tuberculosis and recent BCG exposure.

An 88-year-old woman presented for evaluation of violaceous, minimally tender, nonulcerated, subcutaneous nodules on the legs, arms, and trunk of several weeks’ duration (Figure 1). She had a remote history of tuberculosis as a child, prior to the advent of modern antituberculosis regimens. Her medical history also included hypertension, breast cancer treated with lymph node dissection, gastroesophageal reflux disease, and bladder cancer treated with intravesical BCG 10 years prior to the onset of the nodules. She reported minimal coughing and a 25-lb weight loss over the last year, but she denied night sweats, fever, or chills.

Disseminated erythema induratum, an exceptionally rare variant of panniculitis, may be seen in patients with a remote history of M tuberculosis exposure and/or recent therapeutic BCG exposure. It is imperative to rule out active tuberculosis, especially in elderly patients whose disease predated the advent of modern antituberculosis therapy. Using an IFN-γ release assay in addition to chest radiographs and other clinical stigmata allows differentiation of the etiology of erythema induratum in those patients with tuberculosis who also were treated with BCG.

To the Editor:

Erythema induratum, also known as nodular vasculitis, is a panniculitis that usually affects the lower extremities in middle-aged women. Classically, it has been described as a delayed-type hypersensitivity reaction to Mycobacterium tuberculosis, also known as a tuberculid.^1,2 Other infections, however, also have been implicated as causes of erythema induratum, including bacillus Calmette-Guérin (BCG), the attenuated form of Mycobacterium bovis, which commonly is used for tuberculosis vaccination. Medications also may cause erythema induratum. The characteristic distribution of the nodules on the posterior calves helps to distinguish erythema induratum from other panniculitides. A PubMed search of articles indexed for MEDLINE using the term disseminated erythema induratum revealed few case reports documenting nodules on the arms, thighs, or chest, and only 1 case report of disseminated erythema induratum.^3-8 We describe a rare combination of disseminated erythema induratum in a patient with remote exposure to tuberculosis and recent BCG exposure.

An 88-year-old woman presented for evaluation of violaceous, minimally tender, nonulcerated, subcutaneous nodules on the legs, arms, and trunk of several weeks’ duration (Figure 1). She had a remote history of tuberculosis as a child, prior to the advent of modern antituberculosis regimens. Her medical history also included hypertension, breast cancer treated with lymph node dissection, gastroesophageal reflux disease, and bladder cancer treated with intravesical BCG 10 years prior to the onset of the nodules. She reported minimal coughing and a 25-lb weight loss over the last year, but she denied night sweats, fever, or chills.

Disseminated erythema induratum, an exceptionally rare variant of panniculitis, may be seen in patients with a remote history of M tuberculosis exposure and/or recent therapeutic BCG exposure. It is imperative to rule out active tuberculosis, especially in elderly patients whose disease predated the advent of modern antituberculosis therapy. Using an IFN-γ release assay in addition to chest radiographs and other clinical stigmata allows differentiation of the etiology of erythema induratum in those patients with tuberculosis who also were treated with BCG.

The Diagnosis: Ecthyma Contagiosum (Orf)

Orf, or ecthyma contagiosum, is a zoonotic cutaneous infection caused by the orf DNA virus of the genus Parapoxvirus of the family Poxviridae. It is transmitted to humans through direct contact with infected animals, namely sheep and goats, and as such is most commonly seen in patients with occupational exposure to these animals such as butchers, farmers, veterinarians, and shepherds.^1,2 Human-to-human transmission is exceedingly rare in immunocompetent patients.^2,3 In affected animals, lesions usually are found around the mouth, muzzle, and eyes. In humans, hands are the most commonly affected site, and lesions occur 3 to 10 days after contact. Clinically, the lesions are nonspecific, and our patient presented with tender, erythematous, edematous nodules on the left hand. The differential diagnosis is broad and includes a milker's nodule, pyogenic granuloma, tularemia, anthrax, atypical mycobacterial infection, and sporotrichosis.^1,4,5

The diagnosis usually is made with a thorough history and examination, but in cases of uncertainty, routine pathology with hematoxylin and eosin staining, electron microscopy, or real-time polymerase chain reaction may be used.^2-4 Histopathologically, lesions demonstrate intraepidermal vesicles, vacuolization of keratinocytes of the upper epidermis with characteristic cytoplasmic inclusion bodies, rete ridge elongation, and dilated vessels in the intervening dermal papillae. Central necrosis may occur in well-developed lesions.^2,6 Interestingly, our patient's biopsy exhibited all of these findings (Figure). Immunostains for cytomegalovirus and herpes simplex virus were negative, and Grocott-Gomori methenamine-silver and acid-fast bacillus stains also were negative.

Our patient also developed lymphangitic streaking suggestive of a bacterial superinfection and was treated with a course of intravenous antibiotics. She eventually was discharged with reassurance, wound care instructions, and outpatient antibiotics. She returned to an outside institution's emergency department for further evaluation, and she was admitted for workup. A lesional swab was sent for real-time polymerase chain reaction, which confirmed the diagnosis as orf. When the patient was contacted for follow-up 1 week after biopsy, the hand lesions had notably improved.

Orf is self-limited and typically resolves within 4 to 8 weeks after undergoing evolution through 5 described stages. The maculopapular stage is denoted by enlarging erythematous macule. The targetoid stage is described by a red center within a white halo surrounded by a broader red halo. The nodular stage is self-descriptive. The regenerative and regression stages describe the progressively improving, drier, and crusted nodules.³ 

Because orf is self-limited, no treatment is required, and patients should be counseled that their lesions should resolve within weeks. Complications include lymphangitis, secondary bacterial infection, and erythema multiforme.^1,2,4,5 Immunocompromised patients may develop recalcitrant, giant, or multiple lesions that may be treated with topical imiquimod, topical cidofovir, intralesional interferon alfa, or surgical excision.^1,2,4,7

We present a case of orf to remind practitioners of this rare entity. Although the disease is endemic worldwide, it likely is underreported due to its self-limited nature.^2,4 A careful history may reveal the diagnosis, and overtreatment with antibiotics, many of which have their own significant side-effect profile, can then be avoided. 

Acknowledgment

We thank Eric Behling, MD (Camden, New Jersey), for his contributions in obtaining the histologic images.

The Diagnosis: Ecthyma Contagiosum (Orf)

Orf, or ecthyma contagiosum, is a zoonotic cutaneous infection caused by the orf DNA virus of the genus Parapoxvirus of the family Poxviridae. It is transmitted to humans through direct contact with infected animals, namely sheep and goats, and as such is most commonly seen in patients with occupational exposure to these animals such as butchers, farmers, veterinarians, and shepherds.^1,2 Human-to-human transmission is exceedingly rare in immunocompetent patients.^2,3 In affected animals, lesions usually are found around the mouth, muzzle, and eyes. In humans, hands are the most commonly affected site, and lesions occur 3 to 10 days after contact. Clinically, the lesions are nonspecific, and our patient presented with tender, erythematous, edematous nodules on the left hand. The differential diagnosis is broad and includes a milker's nodule, pyogenic granuloma, tularemia, anthrax, atypical mycobacterial infection, and sporotrichosis.^1,4,5

The diagnosis usually is made with a thorough history and examination, but in cases of uncertainty, routine pathology with hematoxylin and eosin staining, electron microscopy, or real-time polymerase chain reaction may be used.^2-4 Histopathologically, lesions demonstrate intraepidermal vesicles, vacuolization of keratinocytes of the upper epidermis with characteristic cytoplasmic inclusion bodies, rete ridge elongation, and dilated vessels in the intervening dermal papillae. Central necrosis may occur in well-developed lesions.^2,6 Interestingly, our patient's biopsy exhibited all of these findings (Figure). Immunostains for cytomegalovirus and herpes simplex virus were negative, and Grocott-Gomori methenamine-silver and acid-fast bacillus stains also were negative.

Our patient also developed lymphangitic streaking suggestive of a bacterial superinfection and was treated with a course of intravenous antibiotics. She eventually was discharged with reassurance, wound care instructions, and outpatient antibiotics. She returned to an outside institution's emergency department for further evaluation, and she was admitted for workup. A lesional swab was sent for real-time polymerase chain reaction, which confirmed the diagnosis as orf. When the patient was contacted for follow-up 1 week after biopsy, the hand lesions had notably improved.

Orf is self-limited and typically resolves within 4 to 8 weeks after undergoing evolution through 5 described stages. The maculopapular stage is denoted by enlarging erythematous macule. The targetoid stage is described by a red center within a white halo surrounded by a broader red halo. The nodular stage is self-descriptive. The regenerative and regression stages describe the progressively improving, drier, and crusted nodules.³ 

Because orf is self-limited, no treatment is required, and patients should be counseled that their lesions should resolve within weeks. Complications include lymphangitis, secondary bacterial infection, and erythema multiforme.^1,2,4,5 Immunocompromised patients may develop recalcitrant, giant, or multiple lesions that may be treated with topical imiquimod, topical cidofovir, intralesional interferon alfa, or surgical excision.^1,2,4,7

We present a case of orf to remind practitioners of this rare entity. Although the disease is endemic worldwide, it likely is underreported due to its self-limited nature.^2,4 A careful history may reveal the diagnosis, and overtreatment with antibiotics, many of which have their own significant side-effect profile, can then be avoided. 

Acknowledgment

We thank Eric Behling, MD (Camden, New Jersey), for his contributions in obtaining the histologic images.

The Diagnosis: Ecthyma Contagiosum (Orf)

Orf, or ecthyma contagiosum, is a zoonotic cutaneous infection caused by the orf DNA virus of the genus Parapoxvirus of the family Poxviridae. It is transmitted to humans through direct contact with infected animals, namely sheep and goats, and as such is most commonly seen in patients with occupational exposure to these animals such as butchers, farmers, veterinarians, and shepherds.^1,2 Human-to-human transmission is exceedingly rare in immunocompetent patients.^2,3 In affected animals, lesions usually are found around the mouth, muzzle, and eyes. In humans, hands are the most commonly affected site, and lesions occur 3 to 10 days after contact. Clinically, the lesions are nonspecific, and our patient presented with tender, erythematous, edematous nodules on the left hand. The differential diagnosis is broad and includes a milker's nodule, pyogenic granuloma, tularemia, anthrax, atypical mycobacterial infection, and sporotrichosis.^1,4,5

The diagnosis usually is made with a thorough history and examination, but in cases of uncertainty, routine pathology with hematoxylin and eosin staining, electron microscopy, or real-time polymerase chain reaction may be used.^2-4 Histopathologically, lesions demonstrate intraepidermal vesicles, vacuolization of keratinocytes of the upper epidermis with characteristic cytoplasmic inclusion bodies, rete ridge elongation, and dilated vessels in the intervening dermal papillae. Central necrosis may occur in well-developed lesions.^2,6 Interestingly, our patient's biopsy exhibited all of these findings (Figure). Immunostains for cytomegalovirus and herpes simplex virus were negative, and Grocott-Gomori methenamine-silver and acid-fast bacillus stains also were negative.

Our patient also developed lymphangitic streaking suggestive of a bacterial superinfection and was treated with a course of intravenous antibiotics. She eventually was discharged with reassurance, wound care instructions, and outpatient antibiotics. She returned to an outside institution's emergency department for further evaluation, and she was admitted for workup. A lesional swab was sent for real-time polymerase chain reaction, which confirmed the diagnosis as orf. When the patient was contacted for follow-up 1 week after biopsy, the hand lesions had notably improved.

Orf is self-limited and typically resolves within 4 to 8 weeks after undergoing evolution through 5 described stages. The maculopapular stage is denoted by enlarging erythematous macule. The targetoid stage is described by a red center within a white halo surrounded by a broader red halo. The nodular stage is self-descriptive. The regenerative and regression stages describe the progressively improving, drier, and crusted nodules.³ 

Because orf is self-limited, no treatment is required, and patients should be counseled that their lesions should resolve within weeks. Complications include lymphangitis, secondary bacterial infection, and erythema multiforme.^1,2,4,5 Immunocompromised patients may develop recalcitrant, giant, or multiple lesions that may be treated with topical imiquimod, topical cidofovir, intralesional interferon alfa, or surgical excision.^1,2,4,7

We present a case of orf to remind practitioners of this rare entity. Although the disease is endemic worldwide, it likely is underreported due to its self-limited nature.^2,4 A careful history may reveal the diagnosis, and overtreatment with antibiotics, many of which have their own significant side-effect profile, can then be avoided. 

Acknowledgment

We thank Eric Behling, MD (Camden, New Jersey), for his contributions in obtaining the histologic images.