Lupus erythematosus – occurs across a spectrum with localized Discoid lupus to multisystem Systemic lupus (SLE).

• usually confined to the head and neck. More common in African Americans and women.
• Characterized by: persistent localized erythema, adherent scales, follicular plugging (look in the ears for dilated follicles), telangiectasia, atrophy (skin is depressed), depigmentation and alopecia with scarring
• 20% of DLE patients have constitutional symptoms. 10% of DLE patients develop SLE. 5-50% of DLE patients have anti-nuclear antibodies
• discoid lesions not involving the head and neck are much more likely to be SLE
• If systemic disease develops in DLE patients, it will likely be symptomatic. Renal involvement is asymptomatic, follow urinalysis for protein and active sediment (red cells and casts)

• Characterized by Malar rash (butterfly), initially a transient blush across the cheeks and bridge of the nose, eventually becoming fixed erythema
• Atrophy and telangectasia occur
• ½ of SLE patients will have it.
• Alopecia – also common in SLE patients. Either diffuse alopecia, scarring alopecia, or frontal frizzy hair.
• Purpura:
• Macular purpura – due to increased capillary fragility, due to treatment with systemic steroids, or caused by lupus itself
• Palpable purpura - is due to immune complex deposition leading to vasculitis and tissue infarction.
• Vasomotor phenomenon – Raynaud’s phenomenon (white, blue, red hands), Livedo reticularis (netlike erythema over the legs, distinguishable from purpura because it blanches on pressure), and Migraines.
• Photosensitivity – UVB will incite or accentuate the erythema.
• Leg Ulcers and Infarcts – occur in 5-10% of SLE patients; usually just above the ankle.
• Bullae (blisters) due to antibodies to type VII collagen
• Lupus has erythema between the knuckles on the back of the hand. Dermatomyositis has erythema over the knuckles.

• the most photosensitive of the Lupus variants
• associated with a C2 and C4 deficiency
• mothers with subacute lupus are more likely to have babies with congenital 3^o heart block
• neonatal lupus is from maternal antibodies and is gone usually at 6 months when the maternal antibodies are out of the infant’s circulation
• Characterized by: Psoriasiform or polycyclic plaques. A negative ANA when tested with rat substrate (+ with human).

• may occur in children or adults (women more than men) and is characterized by a distinctive skin rash that may accompany or precede the onset of muscle disease
• classic rash takes the form of a lilac or heliotrope discoloration of the upper eyelids with periorbital edema
• often accompanied by a scaling erythematous eruption of dusky red patches over the knuckles, elbows, and knees (Gottron’s papules)
• Dusky erythema occurs on eyelids, butterfly area, neck and upper chest as well
• Subcutaneous calcifications sometimes extrude through the skin (particularly in childhood onset)
• Flexure contraction of the ankles leads to a tiptoe gait in children with the disease
• Muscle weakness is proximal (and particularly affects the shoulders and hips)
• Lupus has erythema between the knuckles on the back of the hand
• Dermatomyositis has erythema over the knuckles
• Dermatomyositis is thought to be mediated through antibodies against endothelial cells of muscle blood vessels and by the Membrane Attack Complex (MAC) of complement
• Polymyositis
• proximal muscle weakness but no dermatological manifestations (mediated by antigen-directed cytotoxicity via cytotoxic T-cells)
• Inclusion-body myositis – more common in men than women, whites than blacks, and patients >50 yrs; proximal muscle weakness, but unlike the others, may have early involvement of distal muscles; No cutaneous findings

• localized scleroderma – cutaneous lesion(s) characterized by indurated, slightly depressed plaques of thickened dermal fibrous tissue, of a whitish or yellowish white color surrounded by a pinkish or purplish halo.
• Progressive systemic sclerosis is characterized by degeneration and fibrosis of the skin, synovia, digital arteries, and the parenchyma and vessels esophagus, intestine, kidney, and lung. Two main types:
• (1) Rapid Cutaneous Sclerosis: 10 yr survival 25%, antibodies to DNA topoisomerase-I, progressive from distal to truncal with few telangiectasias
• (2) CREST (Calcinosis, Raynaud’s phenomenon, Esophageal dysmotility, Sclerodactyly, and Telangiectasia) 10 yr survival 70%, associated with anticentromere antibodies and has a low incidence of renal and pulmonary disease.
• Cutaneous findings of scleroderma:
• Raynaud’s phenomenon: 1^st: cool pallor up to the M-P joint (white), 2^nd: cyanosis of the fingers (blue), 3^rd: intense erythema on rewarming (red). Precedes Scleroderma by a median of two years. Precedes sclerodactyly.
• Acrosclerosis- begins with swelling/puffiness of the fingers, followed by non-pitting edema of the fingers. Gradual tightening and hardening until the fingers are "bound-down". The face, mouth, and chest similarly tighten.
• Periungual telangiectasia – enlarged torturous capillary beds in the nail fold.
• Infarcts of the digits: extremely painful, lead to eventual tapering of the fingers.