Skin signs of rheumatic disease
What is rheumatic disease?
Many autoimmune connective tissue diseases and vascular conditions in rheumatology have cutaneous manifestations.
- Skin signs are useful in the diagnosis of rheumatic disease, as they often precede systemic symptoms.
- They can also act as a prognostic marker and predict systemic involvement.
Rheumatic diseases described on this page are:
- Cutaneous lupus erythematosus
- Systemic sclerosis
- Sjögren syndrome
- Rheumatoid arthritis
- Systemic-onset juvenile arthritis
- Relapsing polychondritis
- Psoriatic arthritis
About 25% of patients with systemic lupus erythematosus (SLE) initially present with skin involvement. It is important to correctly classify cutaneous lupus erythematosus (CLE), as it helps determine the underlying type and severity of SLE.
Skin manifestations of lupus erythematosus (LE) are commonly divided into LE– specific and LE–non–specific disease. Note that four of the nine American College of Rheumatology criteria for SLE are skin signs (malar/butterfly rash, discoid plaques, photosensitivity, and oral ulcers).
- Localised acute CLE — malar/butterfly rash (symmetrical erythema and oedema of cheeks — sparing nasolabial folds — forehead, chin and V of neck)
- Generalised acute CLE — widespread exanthematous eruption on extensor surfaces, trunk, sun–exposed areas and the hands (sparing knuckles)
- Toxic epidermal necrolysis–like — a life–threatening variant with massive epidermal injury. Occurs predominantly on sun–exposed skin with an insidious onset, unlike toxic epidermal necrolysis.
- Typically triggered or exacerbated by exposure to UV light. On recovery may have postinflammatory pigmentation changes without scarring.
Subacute cutaneous LE (SCLE)
- Annular SCLE — subtype with slightly raised red lesion with central clearing
- Papulosquamous SCLE — eczematous or psoriasis–like lesions on sun–exposed skin.
- Start as macules or papules that progress to hyperkeratotic plaques.
- Photosensitive so plaques usually occur on sun exposed skin. Does not lead to scarring but can result in postinflammatory hypo- or hyperpigmentation.
- Monitor to exclude progression to SLE.
- Discoid LE (DLE) — discoid plaques (erythematous, well demarcated plaques covered by scale) that become hyperkeratotic, leading to atrophy and scarring. Dyspigmentation of the peripheries is also common in certain ethnicities (Asian, Indian). There is follicular involvement, causing reversible and irreversible (scarring) alopecia. Affects face, outer ears, neck, sun–exposed areas and lips.
- Hypertrophic/verrucous LE — rare form of CLE with severe hyperkeratosis of extensor surfaces of arms, upper back and face. Has overlapping features with lichen planus.
- Mucosal LE — affects 25% of patients with CLE. Most commonly, painless erythematous patches on oral mucosa that develop into chronic plaques that can centrally ulcerate. These also affect nasal, conjunctival and genital mucosa. Mucosal LE rarely degrades to squamous cell carcinoma (SCC).
- 5–10% of CLE patients develop SLE; CLE is associated with less severe forms of SLE.
- Chronic CLE is not as photosensitive as acute CLE or SCLE.
- Many drugs are thought to induce SLE and drug-induced LE often includes cutaneous signs.
- Examples include hydralazine, isoniazid, chlorpromazine, procainamide, phenytoin, minocycline and anti–TNF medications.
Rarer types of LE
- Lupus profundus/panniculitis — rare form of chronic CLE with firm nodules in lower dermis and subcutaneous tissue. Some use the term lupus panniculitis to refer to subcutaneous involvement only, and lupus profundus when there is a combination of lupus panniculitis with discoid LE. It causes lipoatrophy.
- Chilblain LE — purple/red patches, papules and plaques on toes, fingers and face. Precipitated by exposure to the cold, so often presents in winter. Associated with nail fold telangiectasia.
- LE tumidus — variant of chronic CLE with succulent or indurated erythematous plaques without surface change.
- Photosensitivity — abnormal response to UV light, present in 50–93% of SLE patients
- Mouth ulcers — present in 25–45% of SLE patients
- Non–scarring alopecia in SLE — coarse, dry hair with increased fragility referred to as “lupus hair”.
Cutaneous vascular disease
- Raynaud phenomenon — focal ulceration in finger tips and periungual areas. These can cause pitted scarring, haemorrhage and other nail fold complications.
- Vasculitis — leukocytoclastic vasculitis; urticarial vasculitis (tender papules and plaques over bony prominences); and medium/large vessel vasculitis (purpuric plaques with stellate borders often with necrosis and ulceration or subcutaneous nodules).
- Thromboembolic vasculopathies may have similar clinical presentation as vasculitis but vessel occlusion is due to blood clot.
- Livedo reticularis — net–like blanching red–purple rings commonly arising on the lower limbs.
- Erythromelalgia — burning pain in feet and hands with macular erythema and associated with heat exposure.
- Cutaneous mucinosis — indurated papules, nodules or plaques on trunk or arms.
- Lupus nail dystrophy— nail pitting, ridging, leukonychia, onycholysis and red lunula.
- Spontaneous chronic urticaria
- Lichen planus
- Acanthosis nigricans
- Erythema multiforme
- Cutis laxa
- Rheumatoid nodules
Dermatomyositis, also referred to as idiopathic inflammatory myopathies, is a heterogenous group of autoimmune disorders affecting the skin and/or musculature. Skin signs are critical in diagnosing and classifying dermatomyositis.
- Amyopathic dermatomyositis involves skin changes without muscle or other systemic involvement for more than six months.
- Classic dermatomyositis is more common and results in skin and muscle disease.
The hallmark skin signs of dermatomyositis help differentiate it from CLE.
- Gottron papules: violaceous macules over knuckles and in periungual areas. Often have a depressed centre that is white or atrophic.
- Gottron sign: symmetrical violaceous macules, sometimes with oedema over knuckles, elbows, or knees.
Classic skin signs of dermatomysitis are:
- Periorbital macules — violaceous, erythematous macules of eyelids and periorbital tissue, with or without oedema
- Periungual telangiectasia
- Macules over hands and fingers: symmetric erythema on dorsum of hands and fingers, extensor surface of arms, deltoids, posterior shoulders, V area of neck, central forehead/face and scalp
- Mechanic’s hand — a sign of antisynthetase syndrome; symmetrical chronic eczematous changes affecting the hands, especially along ulnar side of thumb and radial side of fingers.
Other skin signs of dermatomyositis
- Poikiloderma — a combination of violaceous erythema, dyspigmentation, telangiectasia and atrophy of skin; most commonly over the shoulders, back, buttocks and V of neck/chest.
- Calcinosis cutis — painful irregular nodules at sites of friction and trauma, such as elbows, knees and fingers.
Systemic sclerosis is a multi-system form of scleroderma with hallmark skin signs. It is associated with a high mortality and morbidity rate. Clinical features of systemic sclerosis are diverse affecting multiple organs in the body. Two important skin signs are Raynaud phenomenon and skin sclerosis; these help classify the disease into the following subsets.
Localised systemic sclerosis
- Pre-existing chronic Raynaud phenomenon (years)
- Skin sclerosis (scleroderma) sparing proximal sites of body (affects face, neck, extremities).
Visceral disease may begin after a long period of Raynaud disease.
- Pulmonary arterial hypertension
- Pulmonary fibrosis
- Gstrointestinal tract involvement
Diffuse systemic sclerosis
- Raynaud phenomenon (recent onset)
- Proximal scleroderma affecting upper arms, thighs, chest and abdomen
- Acute onset with inflammatory features in first 24 months of disease
- Pulmonary fibrosis, cardiac disease and renal crisis are common.
Overlapping systemic sclerosis
Scleroedema is a rare disease caused by excessive mucin and collagen production. it is associated with preceding infection, diabetes and paraproteinaemia.
- Acute onset of non-pitting induration of neck, shoulders, upper back
- Waxy smooth skin with prominent follicular ostia
Scleromyxoedema is a rare disease caused by excessive mucin production and fibrocyte hyperplasia. It is associated with paraproteinaemia and skin signs.
- Generalized lichenoid eruption — confluent papules scattered on the trunk and extremities (scleromyxedema)
- Discrete papular scleromyxoedema — discrete papules on trunk and extremities, rarely can have nodules (lichen myxedematosus)
- Lichenoid plaques
- Urticarial plaques
Sjögren syndrome is a systemic autoimmune disorder that primarily reduces the function of sweat glands and mucosal mucous glands causing sicca symptoms. It is much more common in women than in men.
Mucosal signs of Sjögren syndrome
- Xerosis — dryness of mucous membrane,
- Xerostomia — predisposes to angular stomatitis
- Dry eyes
Skin signs of Sjögren syndrome
- Eyelid dermatitis
- Vaginal dryness — burning, dyspareunia
- Diffuse hair loss
- Raynaud phenomenon — the most common sign; it can precede sicca symptoms by many years.
- Cutaneous vasculitis
- Non-palpable purpura — crops of round pink lesions that turn purple then brown.
- Palpable purpura represents dermal vasculitis and commonly occurs on buttocks and lower limbs.
- Urticarial vasculitis — erythematous urticated weals that each last more than 24 hours and resolve with hyperpigmentation.
- Necrotising vasculitis initially presents with palpable purpura on the lower limbs that ulcerates and forms scars in 1–4 weeks.
- Annular erythema: annular erythematous plaques with central clearing. Found in Asian patients with anti-Ro/SSA antibodies
- Erythema nodosum
- Erythema multiforme
Rheumatoid arthritis (RA) is a systemic autoimmune inflammatory disorder that causes debilitating symmetrical polyarthritis and other manifestations. One of the seven criteria for RA is the presence of rheumatoid nodules. Skin signs can be divided into RA-specific and nonspecific signs.
RA-specific skin signs
- Rheumatoid nodules (25%) — subcutaneous, firm painless lesions over extensor surfaces of skin as well as heart, lung and muscle. May be complicated by ulceration, bursitis, synovial rupture and gangrene.
- Accelerated rheumatoid nodulosis — painful nodules mainly on hands. Associated with methotrexate therapy in RA patients.
- Rheumatoid vasculitis — late stage presentation with purpura, splinter haemorrhages, nail fold infarcts and peripheral neuropathy. Vasculitis is more common in males. These patients should be started on aggressive therapy for RA.
- Rheumatoid neutrophilic dermatosis — a rare sign in severe seropositive RA causing asymptomatic red urticated papules and plaques on forearms and hands. It resembles Sweet syndrome.
Other signs of vasculitis associated with RA include:
- Erythema elevatum diutinum
- Livedo reticularis
- Digital infarcts
- Urticarial vasculitis
- Atrophie blanche
- Haemorrhagic blisters
- Necrotising granulomatous vasculitis.
RA-nonspecific skin signs
- Pyoderma gangrenosum — tender erythematous or violaceous papules that rapidly develop into necrotic ulcers with ragged swollen edges, usually on the legs.
- Palisaded neutrophilic and granulomatous dermatitis — also known as Winkelmann granuloma. Symmetrical papules/nodules/plaques on extensor surfaces of elbows and fingers, often with central umbilication and crusts.
- Interstitial granulomatous dermatitis — well-demarcated papules or plaques that can coalesce into linear cords. Typically on the trunk and proximal limbs.
Other skin signs arising in rheumatoid arthritis include;
- Cutaneous trophy
- Palmar erythema
- Periungual erythema
- Yellow nail syndrome
- Splinter haemorrhages
- Erythema multiforme
- Alopecia areata.
Systemic–onset juvenile arthritis is a rheumatic disease characterized by high fevers, skin signs (in 95%) and arthritis. Lymphadenopathy, myalgia and abdominal pain may be present. Key signs include:
- Macular exanthema (90%) — non-pruritic and transient exanthema in acutely febrile patients. Discrete macules often on the trunk, koebnerisation is common.
- Rheumatoid-nodule like lesions — nodules on extensor surfaces, clinically and histologically indistinguishable from RA.
Relapsing polychondritis is a rare multisystem autoimmune disease, often associated with an autoimmune or haematological condition. Skin signs in relapsing polychondritis are nonspecific; they are not diagnostic criteria nor are they associated with disease severity.
Hallmark signs of relapsing polychondritis are:
- Auricular inflammation (85%) — ear cartilage swelling, erythema and pain
- Nasal cartilage inflammation (65%) — nasal pain, rhinorrhoea, epistaxis
- Saddle-nose deformity.
Other skin signs include:
- Non-specific vasculitic signs, which are present in 12% of patients with relapsing polychondritis
- Nodules on limbs, purpura, oral aphthous ulcers, papules, livedo reticularis, ulcers and distal necrosis.
Psoriatic arthritis is a form of spondyloarthropathy that can be associated with psoriasis. Psoriasis typically presents with red scaly plaques on scalp and extensor surfaces as well as nail dystrophy. There are subtypes of psoriasis with specific skin signs.
Chronic plaque psoriasis (psoriasis vulgaris)
- Sharply demarcated plaques with silvery scale
- Typically involves the elbows, knees, lower back, scamp and umbilicus.
- Acute eruption of papules and plaques < 1cm in size. Starts on trunk and spread to proximal limbs.
- Affects 60–90% of patients with psoriatic arthritis
- Oil spots, pits, onycholysis and onychodystrophy
- Generalised erythema of the entire skin
- Potentially life-threatening
- Localised palmoplantar pustulosis: sterile pustules on palms and soles
- Generalised pustular psoriasis: acute febrile eruption over trunk and limbs
Uncommon forms of psoriasis
Systemic vasculitis is a heterogenous group of disorders with inflammation of blood vessel walls. The skin and blood vessels have a close anatomical and physiological relationship, hence skin signs are common in vasculitis.
These skin signs prompt an investigation for any systemic involvement of vasculitis. However, the skin signs alone are not sufficient for diagnosis of a specific condition.
Small vessel vasculitis
- Granulomatosis with polyangiitis
- Necrotising granulomatous inflammation and vasculitis
- Potentially lethal
- Skin signs are highly variable and include palpable purpura, deep inflammatory indolent masses, gingival hyperplasia, ulcers, panniculitis and nodules, and pyoderma gangrenosum-like ulcers.
- Eosinophilic granulomatosis with polyangiitis
- Skin signs occur in 50% — palpable purpura, macules, papules, and nodules on extensor surfaces.
- Rarely facial oedema, ulcers, livedo reticularis, and deep pannicular vasculitis.
- Microscopic polyangiitis
- Skin signs typically manifest with purpura and splinter haemorrhages
- Cryoglobulins are circulating immunoglobulins complexed to other immunoglobulins or proteins that reversibly precipitate in the cold. Type I cryoglobulinaemia occurs in single monoclonal immunoglobulins while the mixed type (type II and III) of cryoglobulinaemia result in vasculitis with glomerulonephritis.
- Purpura at distal sites (fingers and toes) is a hallmark sign.
- Type I: non-inflammatory purpura, Raynaud phenomenon, livedo reticularis, ulceration, acrocyanosis, and gangrene.
- Mixed type: palpable purpura (intermittent lasting 3–10 days); Raynaud phenomenon, psoriasis, cutaneous vasculitis, porphyria cutanea tarda, lichen planus, urticaria, and cold urticaria.
- Urticarial vasculitis is a leukocytoclastic vasculitis affecting about 5% of people with urticaria.
- Skin signs are tender, burning and painful papules or wheals that persist for 24–72 hours.
- Hypocomplementaemic urticarial vasculitis is a syndrome with chronic urticarial weals occuring for more than 6 months, hypocomplementaemia and leukocytoclastic vasculitis on biopsy.
- Immune-complex mediated form of small vessel vasculitis.
- Occurs in children usually after a respiratory tract infection.
- Skin signs are purpura (leukocytoclastic vasculitis) and urticaria with local oedema.
- Can also cause intestinal vasculitis, intussusception and glomerulonephritis.
- Joint symptoms are more common in adults than in children.
- Chronic leukocytoclastic vasculitis causing symmetrical red/violaceous/yellow–brown papules, nodules or plaques.
- Common on extensor surfaces of hands, knees, legs, and Achilles tendon.
- A type of small vessel vasculopathy.
- Presents with papules with a central white depression. Heals with a white scar.
Rare forms of small vessel vasculitis
Medium vessel vasculitis
- Skin signs (15%) include bright red/blue/violet subcutaneous nodules that become confluent and painful, livedo reticularis, ulcers on lower limbs and postinflammatory hyperpigmentation.
- Vasculopathy due to thrombosis of small or medium vessels; associated with smoking.
- Skin signs are painful purple/blue fingers/toes. Often asymmetrical and associated with cold climate or exercise. May ulcerate or become gangrenous leading to amputation of a limb.
- Acute multisystem vasculitis with fever, systemic and cardiac manifestations
- Most common cause of heart disease in children
- Skin signs are polymorphous exanthem (90% found on the trunk and proximal limbs); perineal eruption (macular or plaque type erythema which desquamates within 48 hours); oedema and erythema of palms/soles; oral signs (“cherry” lips, dry and cracked, “strawberry” tongue with hypertrophied papillae, and hyperaemia); periungual desquamation.
Medium-sized vessel vasculitis
Large vessel vasculitis
- Affects women aged 10–30 years; there are no associated skin signs.
Giant cell arteritis
- Affects those 55 years of age or greater.
- Skin signs are cyanosis and pallor of extremities, scalp tenderness and sometimes, necrosis.
- Inflammation predominantly of aorta and its branches.
- Causes hearing loss, vertigo and eye symptoms.
- There are no associated skin signs.
- Multisystem inflammatory disease affecting skin, eyes, joints and other systems.
- Skin signs are recurrent oral aphthous ulcers (80%), genital ulcers (64-88%), erythema nodosum, pustules and superficial thrombophlebitis.