Davinder Parsad, MD

A housewife in her 50s presented with photosensitivity and recent-onset roughness on her index fingers and thumbs. Examination showed asymptomatic, bilaterally symmetrical, hyperkeratotic, scaly, fissured plaques with hyperpigmentation on the radial aspect of the index finger of both hands, extending to the ulnar aspect of the thumbs and sparing the palmar aspect of both (Figure 1). Palms, soles, and other fingers were normal.

Nail fold capillaroscopy did not reveal telangiectasia or ragged cuticles. Further examination of the skin showed confluent macular violaceous erythema on the eyelids (suggestive of the heliotrope sign), V area of the neck, upper arms, and back.

She also had a low-grade intermittent fever for the past 2 months, as well as difficulty in getting up from a squatting position and combing her hair, dyspnea on exertion, blue discoloration of the fingers on exposure to cold, and intermittent pain, stiffness, and swelling in the small joints of both hands that was worse in the morning and seemed to be relieved by activity. She had no history of dysphagia or nasal regurgitation of food. Strength against resistance was reduced in both arms and knee extensors. A diagnosis of dermatomyositis with “mechanic’s hands” was considered.

Laboratory testing was negative for antinuclear antibodies and showed elevated creatine kinase and positive anti-Jo-1 antibodies. High-resolution computed tomography of the chest showed evidence of interstitial lung disease. Features were consistent with antisynthetase syndrome and dermatomyositis. An age-appropriate malignancy screen was normal.

The patient was started on oral prednisolone 60 mg, hydroxychloroquine 300 mg, and azathioprine 100 mg. For her hands, topical clobetasol propionate 0.05% with 3% salicyclic acid and emollients were advised. Her muscle weakness improved considerably after 2 months, but the photosensitivity and mechanic’s hands improved only minimally.

ANTISYNTHETASE SYNDROME

Antisynthetase syndrome is a subset of idiopathic inflammatory myopathies characterized by fever, Raynaud phenomenon, arthritis, myositis, interstitial lung disease, and mechanic’s hands. It is associated with myositis-specific antibodies directed against aminoacyl-tRNA synthetases, of which anti-Jo-1 is the most common. Other antibodies including anti-PL-7 and anti-PL-12 may be present, whereas antinuclear antibodies may be negative.

Mechanic’s hands is seen in about 30% of patients with antisynthetase syndrome and is an important physical sign, as its presence in a patient with myositis and arthritis prompts an evaluation to exclude interstitial lung disease. Its onset later in the disease course may herald the flare-up of interstitial lung disease.¹ A similar hyperkeratosis may also affect the feet, and the importance of a careful cutaneous examination of the hands and feet should be stressed in patients presenting with polymyositis and dermatomyositis.

In contrast, hyperkeratotic eczema of the hand is usually pruritic, and involvement of the tips and palmar aspects of the fingers and palms is characteristic.^2,3 Vesicles (pompholyx) and coarse pitting of the nails may also be seen in eczema. Other features that help rule out eczema are the development of these features over a short period of time, asymptomatic nature, presence of systemic symptoms, and involvement of only the lateral margins of the index fingers, with no involvement of the palmar aspects and other fingers.

Degenerative collagenous plaque, closely resembling mechanic’s hands, is common in elderly people with photodamaged skin. It is asymptomatic, is not associated with systemic illness, and features clumping and thickening of elastic fibers on histopathology.

Association with cancer risk

Though antisynthetase syndrome was not previously considered to be associated with an increased risk of malignancy, a retrospective review of 124 patients with antisynthetase syndrome recently showed a malignancy risk of 6.5%.⁴ Overall, the data regarding the association of malignancy and antisynthetase syndrome are conflicting, and this needs further study. Therefore, an age-appropriate malignancy screen is recommended.^4–6 Also, the presence of malignancy and interstitial lung disease is associated with a poor prognosis in these patients.

Treatment

Glucocorticoids are the mainstay of treatment, and azathioprine and methotrexate are important steroid-sparing agents.^5,7 Use of methotrexate warrants caution in patients with interstitial lung disease, since methotrexate itself can cause pulmonary fibrosis.

In our patient, prednisolone was slowly tapered to 20 mg/day, and hydroxychloroquine and azathioprine were continued at 300 mg/day and 100 mg/day, respectively. Topical treatment for mechanic’s hands was continued, with only minimal improvement.             

A housewife in her 50s presented with photosensitivity and recent-onset roughness on her index fingers and thumbs. Examination showed asymptomatic, bilaterally symmetrical, hyperkeratotic, scaly, fissured plaques with hyperpigmentation on the radial aspect of the index finger of both hands, extending to the ulnar aspect of the thumbs and sparing the palmar aspect of both (Figure 1). Palms, soles, and other fingers were normal.

Nail fold capillaroscopy did not reveal telangiectasia or ragged cuticles. Further examination of the skin showed confluent macular violaceous erythema on the eyelids (suggestive of the heliotrope sign), V area of the neck, upper arms, and back.

She also had a low-grade intermittent fever for the past 2 months, as well as difficulty in getting up from a squatting position and combing her hair, dyspnea on exertion, blue discoloration of the fingers on exposure to cold, and intermittent pain, stiffness, and swelling in the small joints of both hands that was worse in the morning and seemed to be relieved by activity. She had no history of dysphagia or nasal regurgitation of food. Strength against resistance was reduced in both arms and knee extensors. A diagnosis of dermatomyositis with “mechanic’s hands” was considered.

Laboratory testing was negative for antinuclear antibodies and showed elevated creatine kinase and positive anti-Jo-1 antibodies. High-resolution computed tomography of the chest showed evidence of interstitial lung disease. Features were consistent with antisynthetase syndrome and dermatomyositis. An age-appropriate malignancy screen was normal.

The patient was started on oral prednisolone 60 mg, hydroxychloroquine 300 mg, and azathioprine 100 mg. For her hands, topical clobetasol propionate 0.05% with 3% salicyclic acid and emollients were advised. Her muscle weakness improved considerably after 2 months, but the photosensitivity and mechanic’s hands improved only minimally.

ANTISYNTHETASE SYNDROME

Antisynthetase syndrome is a subset of idiopathic inflammatory myopathies characterized by fever, Raynaud phenomenon, arthritis, myositis, interstitial lung disease, and mechanic’s hands. It is associated with myositis-specific antibodies directed against aminoacyl-tRNA synthetases, of which anti-Jo-1 is the most common. Other antibodies including anti-PL-7 and anti-PL-12 may be present, whereas antinuclear antibodies may be negative.

Mechanic’s hands is seen in about 30% of patients with antisynthetase syndrome and is an important physical sign, as its presence in a patient with myositis and arthritis prompts an evaluation to exclude interstitial lung disease. Its onset later in the disease course may herald the flare-up of interstitial lung disease.¹ A similar hyperkeratosis may also affect the feet, and the importance of a careful cutaneous examination of the hands and feet should be stressed in patients presenting with polymyositis and dermatomyositis.

In contrast, hyperkeratotic eczema of the hand is usually pruritic, and involvement of the tips and palmar aspects of the fingers and palms is characteristic.^2,3 Vesicles (pompholyx) and coarse pitting of the nails may also be seen in eczema. Other features that help rule out eczema are the development of these features over a short period of time, asymptomatic nature, presence of systemic symptoms, and involvement of only the lateral margins of the index fingers, with no involvement of the palmar aspects and other fingers.

Degenerative collagenous plaque, closely resembling mechanic’s hands, is common in elderly people with photodamaged skin. It is asymptomatic, is not associated with systemic illness, and features clumping and thickening of elastic fibers on histopathology.

Association with cancer risk

Though antisynthetase syndrome was not previously considered to be associated with an increased risk of malignancy, a retrospective review of 124 patients with antisynthetase syndrome recently showed a malignancy risk of 6.5%.⁴ Overall, the data regarding the association of malignancy and antisynthetase syndrome are conflicting, and this needs further study. Therefore, an age-appropriate malignancy screen is recommended.^4–6 Also, the presence of malignancy and interstitial lung disease is associated with a poor prognosis in these patients.

Treatment

Glucocorticoids are the mainstay of treatment, and azathioprine and methotrexate are important steroid-sparing agents.^5,7 Use of methotrexate warrants caution in patients with interstitial lung disease, since methotrexate itself can cause pulmonary fibrosis.

In our patient, prednisolone was slowly tapered to 20 mg/day, and hydroxychloroquine and azathioprine were continued at 300 mg/day and 100 mg/day, respectively. Topical treatment for mechanic’s hands was continued, with only minimal improvement.             

A housewife in her 50s presented with photosensitivity and recent-onset roughness on her index fingers and thumbs. Examination showed asymptomatic, bilaterally symmetrical, hyperkeratotic, scaly, fissured plaques with hyperpigmentation on the radial aspect of the index finger of both hands, extending to the ulnar aspect of the thumbs and sparing the palmar aspect of both (Figure 1). Palms, soles, and other fingers were normal.

Nail fold capillaroscopy did not reveal telangiectasia or ragged cuticles. Further examination of the skin showed confluent macular violaceous erythema on the eyelids (suggestive of the heliotrope sign), V area of the neck, upper arms, and back.

She also had a low-grade intermittent fever for the past 2 months, as well as difficulty in getting up from a squatting position and combing her hair, dyspnea on exertion, blue discoloration of the fingers on exposure to cold, and intermittent pain, stiffness, and swelling in the small joints of both hands that was worse in the morning and seemed to be relieved by activity. She had no history of dysphagia or nasal regurgitation of food. Strength against resistance was reduced in both arms and knee extensors. A diagnosis of dermatomyositis with “mechanic’s hands” was considered.

Laboratory testing was negative for antinuclear antibodies and showed elevated creatine kinase and positive anti-Jo-1 antibodies. High-resolution computed tomography of the chest showed evidence of interstitial lung disease. Features were consistent with antisynthetase syndrome and dermatomyositis. An age-appropriate malignancy screen was normal.

The patient was started on oral prednisolone 60 mg, hydroxychloroquine 300 mg, and azathioprine 100 mg. For her hands, topical clobetasol propionate 0.05% with 3% salicyclic acid and emollients were advised. Her muscle weakness improved considerably after 2 months, but the photosensitivity and mechanic’s hands improved only minimally.

ANTISYNTHETASE SYNDROME

Antisynthetase syndrome is a subset of idiopathic inflammatory myopathies characterized by fever, Raynaud phenomenon, arthritis, myositis, interstitial lung disease, and mechanic’s hands. It is associated with myositis-specific antibodies directed against aminoacyl-tRNA synthetases, of which anti-Jo-1 is the most common. Other antibodies including anti-PL-7 and anti-PL-12 may be present, whereas antinuclear antibodies may be negative.

Mechanic’s hands is seen in about 30% of patients with antisynthetase syndrome and is an important physical sign, as its presence in a patient with myositis and arthritis prompts an evaluation to exclude interstitial lung disease. Its onset later in the disease course may herald the flare-up of interstitial lung disease.¹ A similar hyperkeratosis may also affect the feet, and the importance of a careful cutaneous examination of the hands and feet should be stressed in patients presenting with polymyositis and dermatomyositis.

In contrast, hyperkeratotic eczema of the hand is usually pruritic, and involvement of the tips and palmar aspects of the fingers and palms is characteristic.^2,3 Vesicles (pompholyx) and coarse pitting of the nails may also be seen in eczema. Other features that help rule out eczema are the development of these features over a short period of time, asymptomatic nature, presence of systemic symptoms, and involvement of only the lateral margins of the index fingers, with no involvement of the palmar aspects and other fingers.

Degenerative collagenous plaque, closely resembling mechanic’s hands, is common in elderly people with photodamaged skin. It is asymptomatic, is not associated with systemic illness, and features clumping and thickening of elastic fibers on histopathology.

Association with cancer risk

Though antisynthetase syndrome was not previously considered to be associated with an increased risk of malignancy, a retrospective review of 124 patients with antisynthetase syndrome recently showed a malignancy risk of 6.5%.⁴ Overall, the data regarding the association of malignancy and antisynthetase syndrome are conflicting, and this needs further study. Therefore, an age-appropriate malignancy screen is recommended.^4–6 Also, the presence of malignancy and interstitial lung disease is associated with a poor prognosis in these patients.

Treatment

Glucocorticoids are the mainstay of treatment, and azathioprine and methotrexate are important steroid-sparing agents.^5,7 Use of methotrexate warrants caution in patients with interstitial lung disease, since methotrexate itself can cause pulmonary fibrosis.

In our patient, prednisolone was slowly tapered to 20 mg/day, and hydroxychloroquine and azathioprine were continued at 300 mg/day and 100 mg/day, respectively. Topical treatment for mechanic’s hands was continued, with only minimal improvement.             

A woman in her 30s presented with an itchy skin-colored rash over her left scapular region that had first appeared 8 years earlier. It had started as itchy skin-colored papules that coalesced to a patch and later became hyperpigmented because of repeated scratching.

She had undergone total thyroidectomy for medullary thyroid carcinoma 1 year ago, and the rash had been diagnosed at that time as lichen planus. She was referred to us by her physician for histopathologic confirmation of the lesions. She denied any history of episodic headache or palpitation.

Her blood pressure was 134/86 mm Hg. On physical examination, groups of small hyperpigmented papules were noted over the left scapula (Figure 1).

Histopathologic study of a biopsy sample revealed focal degeneration of the basal cell layer with pigment incontinence and deposition of eosinophilic hyaline material along the tip of the papillary dermis, which was confirmed to be amyloid (Figure 2).

Her urine normetanephrine excretion was elevated at 1,425 μg/day (reference range 148–560), and her metanephrine excretion was also high at 2,024 μg/day (reference range 44–261).

Contrast-enhanced computed tomography of the abdomen revealed a right adrenal mass (Figure 3). Biopsy study of the mass confirmed pheochromocytoma, a manifestation of multiple endocrine neoplasia (MEN) type 2A.

At a 3-month follow-up visit, the woman’s skin lesions had improved with twice-a-day application of mometasone 0.1% cream; she was lost to follow-up after that visit.

MULTIPLE ENDOCRINE NEOPLASIA

Our patient’s scapular lesions and first-degree family history of MEN type 2A confirmed the diagnosis of the newly recognized variant, MEN type 2A-related cutaneous lichen amyloidosis, in which the characteristic pigmented scapular rash typically predates the first diagnosis of neoplasia.¹ The dermal amyloidosis is caused by deposition of keratinlike peptides rather than calcitoninlike peptides.²

A recent systematic review on MEN type 2A with cutaneous lichen amyloidosis showed a female preponderance and a high penetrance of cutaneous lichen amyloidosis, which was the second most frequent manifestation of the syndrome, preceded only by medullary thyroid carcinoma.¹

As in our patient’s case, scapular rash and a history of medullary thyroid carcinoma should prompt an investigation for MEN type 2A. These patients should be closely followed for underlying MEN type 2A-related neoplasms.

The mucosal neuromas and skin lipomas seen in MEN type 1 and MEN type 2B are absent in MEN type 2A.³ Cutaneous lichen amyloidosis is the only dermatologic marker for MEN type 2A. Owing to a similar genetic background, cutaneous lichen amyloidosis is also associated with familial medullary thyroid carcinoma, another rare variant of MEN type 2A.⁴

DIFFERENTIAL DIAGNOSIS

Notalgia paresthetica is a unilateral chronic neuropathic pruritus on the back, mostly located between the shoulders and corresponding to the second and the sixth thoracic nerves. It is mostly attributed to compression of spinal nerves by an abnormality of the thoracic spine.⁵ In our patient, this was ruled out by the radiologic evaluation.

Before MEN type 2A with cutaneous lichen amyloidosis was recognized as a variant of MEN type 2A, lesions suggestive of notalgia paresthetica were reported with MEN type 2A.³ The classic infrascapular location, history of painful neck muscle spasms, touch hyperesthesia of the lesions, and absence of amyloid deposits on histopathologic study help to differentiate notalgia paresthetica from cutaneous lichen amyloidosis. However, later phases of notalgia paresthetica may show amyloid deposits on histopathologic study, while detection of a scant amount of amyloid is difficult in the early stages of cutaneous lichen amyloidosis.

TAKE-HOME POINT

Cutaneous lichen amyloidosis is usually seen on the extensor surfaces of the extremities. It is considered benign, caused by filamentous degeneration of keratinocytes from repeated scratching. But cutaneous lichen amyloidosis at an early age in the scapular area of women warrants a detailed family history for endocrine neoplasia, blood pressure monitoring, thyroid palpation, and blood testing for serum calcium, calcitonin, and parathyroid hormone.

A woman in her 30s presented with an itchy skin-colored rash over her left scapular region that had first appeared 8 years earlier. It had started as itchy skin-colored papules that coalesced to a patch and later became hyperpigmented because of repeated scratching.

She had undergone total thyroidectomy for medullary thyroid carcinoma 1 year ago, and the rash had been diagnosed at that time as lichen planus. She was referred to us by her physician for histopathologic confirmation of the lesions. She denied any history of episodic headache or palpitation.

Her blood pressure was 134/86 mm Hg. On physical examination, groups of small hyperpigmented papules were noted over the left scapula (Figure 1).

Histopathologic study of a biopsy sample revealed focal degeneration of the basal cell layer with pigment incontinence and deposition of eosinophilic hyaline material along the tip of the papillary dermis, which was confirmed to be amyloid (Figure 2).

Her urine normetanephrine excretion was elevated at 1,425 μg/day (reference range 148–560), and her metanephrine excretion was also high at 2,024 μg/day (reference range 44–261).

Contrast-enhanced computed tomography of the abdomen revealed a right adrenal mass (Figure 3). Biopsy study of the mass confirmed pheochromocytoma, a manifestation of multiple endocrine neoplasia (MEN) type 2A.

At a 3-month follow-up visit, the woman’s skin lesions had improved with twice-a-day application of mometasone 0.1% cream; she was lost to follow-up after that visit.

MULTIPLE ENDOCRINE NEOPLASIA

Our patient’s scapular lesions and first-degree family history of MEN type 2A confirmed the diagnosis of the newly recognized variant, MEN type 2A-related cutaneous lichen amyloidosis, in which the characteristic pigmented scapular rash typically predates the first diagnosis of neoplasia.¹ The dermal amyloidosis is caused by deposition of keratinlike peptides rather than calcitoninlike peptides.²

A recent systematic review on MEN type 2A with cutaneous lichen amyloidosis showed a female preponderance and a high penetrance of cutaneous lichen amyloidosis, which was the second most frequent manifestation of the syndrome, preceded only by medullary thyroid carcinoma.¹

As in our patient’s case, scapular rash and a history of medullary thyroid carcinoma should prompt an investigation for MEN type 2A. These patients should be closely followed for underlying MEN type 2A-related neoplasms.

The mucosal neuromas and skin lipomas seen in MEN type 1 and MEN type 2B are absent in MEN type 2A.³ Cutaneous lichen amyloidosis is the only dermatologic marker for MEN type 2A. Owing to a similar genetic background, cutaneous lichen amyloidosis is also associated with familial medullary thyroid carcinoma, another rare variant of MEN type 2A.⁴

DIFFERENTIAL DIAGNOSIS

Notalgia paresthetica is a unilateral chronic neuropathic pruritus on the back, mostly located between the shoulders and corresponding to the second and the sixth thoracic nerves. It is mostly attributed to compression of spinal nerves by an abnormality of the thoracic spine.⁵ In our patient, this was ruled out by the radiologic evaluation.

Before MEN type 2A with cutaneous lichen amyloidosis was recognized as a variant of MEN type 2A, lesions suggestive of notalgia paresthetica were reported with MEN type 2A.³ The classic infrascapular location, history of painful neck muscle spasms, touch hyperesthesia of the lesions, and absence of amyloid deposits on histopathologic study help to differentiate notalgia paresthetica from cutaneous lichen amyloidosis. However, later phases of notalgia paresthetica may show amyloid deposits on histopathologic study, while detection of a scant amount of amyloid is difficult in the early stages of cutaneous lichen amyloidosis.

TAKE-HOME POINT

Cutaneous lichen amyloidosis is usually seen on the extensor surfaces of the extremities. It is considered benign, caused by filamentous degeneration of keratinocytes from repeated scratching. But cutaneous lichen amyloidosis at an early age in the scapular area of women warrants a detailed family history for endocrine neoplasia, blood pressure monitoring, thyroid palpation, and blood testing for serum calcium, calcitonin, and parathyroid hormone.

A woman in her 30s presented with an itchy skin-colored rash over her left scapular region that had first appeared 8 years earlier. It had started as itchy skin-colored papules that coalesced to a patch and later became hyperpigmented because of repeated scratching.

She had undergone total thyroidectomy for medullary thyroid carcinoma 1 year ago, and the rash had been diagnosed at that time as lichen planus. She was referred to us by her physician for histopathologic confirmation of the lesions. She denied any history of episodic headache or palpitation.

Her blood pressure was 134/86 mm Hg. On physical examination, groups of small hyperpigmented papules were noted over the left scapula (Figure 1).

Histopathologic study of a biopsy sample revealed focal degeneration of the basal cell layer with pigment incontinence and deposition of eosinophilic hyaline material along the tip of the papillary dermis, which was confirmed to be amyloid (Figure 2).

Her urine normetanephrine excretion was elevated at 1,425 μg/day (reference range 148–560), and her metanephrine excretion was also high at 2,024 μg/day (reference range 44–261).

Contrast-enhanced computed tomography of the abdomen revealed a right adrenal mass (Figure 3). Biopsy study of the mass confirmed pheochromocytoma, a manifestation of multiple endocrine neoplasia (MEN) type 2A.

At a 3-month follow-up visit, the woman’s skin lesions had improved with twice-a-day application of mometasone 0.1% cream; she was lost to follow-up after that visit.

MULTIPLE ENDOCRINE NEOPLASIA

Our patient’s scapular lesions and first-degree family history of MEN type 2A confirmed the diagnosis of the newly recognized variant, MEN type 2A-related cutaneous lichen amyloidosis, in which the characteristic pigmented scapular rash typically predates the first diagnosis of neoplasia.¹ The dermal amyloidosis is caused by deposition of keratinlike peptides rather than calcitoninlike peptides.²

A recent systematic review on MEN type 2A with cutaneous lichen amyloidosis showed a female preponderance and a high penetrance of cutaneous lichen amyloidosis, which was the second most frequent manifestation of the syndrome, preceded only by medullary thyroid carcinoma.¹

As in our patient’s case, scapular rash and a history of medullary thyroid carcinoma should prompt an investigation for MEN type 2A. These patients should be closely followed for underlying MEN type 2A-related neoplasms.

The mucosal neuromas and skin lipomas seen in MEN type 1 and MEN type 2B are absent in MEN type 2A.³ Cutaneous lichen amyloidosis is the only dermatologic marker for MEN type 2A. Owing to a similar genetic background, cutaneous lichen amyloidosis is also associated with familial medullary thyroid carcinoma, another rare variant of MEN type 2A.⁴

DIFFERENTIAL DIAGNOSIS

Notalgia paresthetica is a unilateral chronic neuropathic pruritus on the back, mostly located between the shoulders and corresponding to the second and the sixth thoracic nerves. It is mostly attributed to compression of spinal nerves by an abnormality of the thoracic spine.⁵ In our patient, this was ruled out by the radiologic evaluation.

Before MEN type 2A with cutaneous lichen amyloidosis was recognized as a variant of MEN type 2A, lesions suggestive of notalgia paresthetica were reported with MEN type 2A.³ The classic infrascapular location, history of painful neck muscle spasms, touch hyperesthesia of the lesions, and absence of amyloid deposits on histopathologic study help to differentiate notalgia paresthetica from cutaneous lichen amyloidosis. However, later phases of notalgia paresthetica may show amyloid deposits on histopathologic study, while detection of a scant amount of amyloid is difficult in the early stages of cutaneous lichen amyloidosis.

TAKE-HOME POINT

Cutaneous lichen amyloidosis is usually seen on the extensor surfaces of the extremities. It is considered benign, caused by filamentous degeneration of keratinocytes from repeated scratching. But cutaneous lichen amyloidosis at an early age in the scapular area of women warrants a detailed family history for endocrine neoplasia, blood pressure monitoring, thyroid palpation, and blood testing for serum calcium, calcitonin, and parathyroid hormone.