In lupus erythematosus (LE), the skin may be the sole organ system
affected, or it may be involved as a manifestation of systemic LE.
Cutaneous LE may be classified as (1) acute cutaneous LE, (2) subacute
cutaneous LE, or (3) chronic cutaneous LE, of which the most common
variant is discoid LE. Transient skin involvement resembling subacute
cutaneous LE is characteristic of neonatal LE. Sunlight is an important
stimulus in the initiation of cutaneous LE.
The most common skin manifestation of systemic lupus erythematosus
(SLE) is acute cutaneous lupus erythematosus, characterized by an erythematous
eruption that may be localized to the malar area of the face, the “butterfly rash,” or
may be more generalized (Fig. 204-1). SLE
is discussed in further detail in Chapter 204.
The rash is photosensitive and may present as macular erythema or
as erythematous, edematous, scaly plaques on the malar area and
nasal bridge. Similar lesions may occur elsewhere on the body, especially
in areas exposed to sunlight. Patients with SLE may also develop
cheilitis and scarring plaques identical to those seen in discoid
lupus erythematosus (DLE).11
Subacute cutaneous lupus erythematosus is characterized
by a photosensitive, papulosquamous, or annular-polycyclic erythema
associated with positive serology for anti-Ro (SSA) or anti-La (SSB)
antibodies. Although usually a benign disorder with mild systemic symptoms,
subacute cutaneous lupus erythematosus may sometimes occur in patients
with systemic lupus erythematosus.
Nonspecific cutaneous findings are common in SLE. These include
a nonscarring alopecia, mucosal ulceration (most commonly on the hard
palate), and capillary loop telangiectasia of the proximal nail
folds. Raynaud phenomenon, cold-induced distal acrocyanosis, or
chilblainlike lesions (chilblain LE) may be associated with digital
ulcerations. Cutaneous leukocytoclastic vasculitis manifested by
palpable purpura or livedo reticularis with ulceration may also
be seen. Rare cutaneous manifestations of SLE include urticarial
vasculitis, bullous LE, and lupus panniculitis.
The histopathologic examination of biopsies of the cutaneous
lesions in SLE is similar to that of DLE (see next section), but
the characteristic features may not all be present and are often
more subtle. The immunopathology of skin lesions in SLE is also
similar to DLE. Immunopathology of nonlesional, sun-exposed skin
(the lupus band test) is positive in 80% of patients with
SLE and may be a useful diagnostic test. Positive immunopathology
in sun-shielded (eg, buttock) skin is less frequent but is correlated
with more severe disease and especially with renal involvement.
Immunopathology of LE vasculitis may show IgG, IgM, and/or
complement around superficial venules, in addition to deposits in
The severity of skin disease in SLE frequently waxes and wanes in
parallel with the systemic disease. Sun avoidance and the use of broad-spectrum
sunscreens are extremely important. Some cutaneous manifestations
of SLE may respond to topical or intralesional corticosteroids.
Antimalarials such as hydroxychloroquine or chloroquine may also
be helpful. The use of systemic steroids or cytotoxic agents is
determined by the activity of extracutaneous disease.
Discoid lupus erythematosus (DLE) is a chronic, disfiguring dermatosis
that not uncommonly begins in late adolescence. The characteristic
lesion is an erythematous scaly plaque that shows a triad of atrophy,
telangiectasia, and follicular plugging. Hypopigmentation, depigmentation, or
hyperpigmentation and scarring commonly develop with time. The scalp,
face, and the pinna of the ear are the sites of predilection, but
lesions may be found on other sun-exposed sites. Histopathology
is usually diagnostic in DLE and shows thinning of the epidermis,
degeneration of the basal cell layer, thickening of the epidermal
basement membrane, a patchy lymphohistiocytic infiltrate in the
dermis, and dilated follicular orifices with keratin plugs. The
diagnosis of DLE may be confirmed by immunofluorescence of lesional
skin, where deposition of IgG, IgM, and/or complement is observed
in a broad band just below the dermal-epidermal junction. Laboratory
studies including antinuclear antibodies and anti-DNA antibodies
are usually normal or negative. Only a small number of patients
with DLE progress to SLE. However, lesions that are characteristic
of DLE are seen in about 20% of patients with systemic
LE during the course of their disease.
Treatment of DLE includes careful avoidance of sun exposure and
the regular use of broad-spectrum (UVB and UVA) sunscreens with
SPF 30 or higher. Potent topical (eg, fluocinonide ointment) or
intralesional corticosteroids are the most commonly employed forms
of therapy. Patients with disfiguring disease may benefit from antimalarials
Neonatal lupus erythematosus (NLE) is associated with transplacental
passage of maternal anti-Ro (SSA), anti-La (SSB), or anti-U1RNP
antibodies from mother to fetus. It is characterized most commonly
by a transient skin eruption and/or permanent congenital
heart block. A minority of infants have both skin and heart disease.
Other manifestations of NLE include thrombocytopenia, leukopenia,
hemolytic anemia, hepatitis, pulmonary disease, and central nervous
system involvement. The skin lesions of NLE are characteristically
annular, erythematous patches or plaques over the head and neck
(Fig. 362-2).12 NLE may also present
with diffuse facial erythema, particularly in a periorbital distribution
referred to as “raccoon eyes,” or telangiectatic
lesions. Annular or macular lesions occur on the trunk and limbs
and can be widespread. The skin eruption may be present at birth
or become apparent during the first few months of life. Photosensitivity
appears to be a factor in precipitating NLE dermatitis.
Neonatal lupus erythematosus.
A diagnosis of NLE is confirmed by positive serology for anti-Ro
(SSA) antibodies in the mother and infant. Anti-La (SSB) antibodies are
found less commonly, and NLE associated with anti-U1RNP antibodies
is rare. The mother may have systemic or acute cutaneous lupus erythematosus
or Sjögren syndrome, but many are asymptomatic or have
only minor symptoms and signs of connective tissue disease. Mothers
of affected infants should be carefully evaluated and followed and
advised about the risk of NLE in future pregnancies.
Passively transferred antibodies in the infant are lost during
the first 6 months of life. Congenital heart block, caused by maldevelopment and
scarring of the conduction system, may require the implantation
of a permanent pacemaker. No treatment of the cutaneous lesions other
than sun protection is usually required. These lesions usually resolve
spontaneously by 6 months with little or no scarring. Hematologic
abnormalities, hepatitis, and other systemic manifestations of NLE
are also transient.
Dermatomyositis is a chronic inflammatory disease involving skeletal
muscle and skin. It usually presentswith proximal muscle weakness
and a rash, but
the rash may precede the onset of muscle disease. There are occasionally
children who develop the typical rash of dermatomyositis with little
or no muscle disease. A purplish discoloration of the periorbital
skin (heliotrope sign) is typical but may be subtle or absent. A
diffuse macular erythema or violaceous discoloration commonly affects
the malar areas of the face and may be confused with acute cutaneous
LE (Fig. 205-1).13 Erythema or erythematous
scaly plaques are seen on the elbows, knees, upper back, chest,
and buttocks. These lesions may resemble psoriasis but are less
scaly and have ill-defined margins. Flesh-colored or erythematous
papules over the metacarpophalangeal joints (Gottron sign) are highly characteristic
(Fig. 362-3), as are capillary loop telangiectases
of the periungual skin and gum margins. Dermatomyositis is discussed
further in Chapter 205.
Dermatomyositis: Gottron papules on dorsum of hands.
Scleroderma may be localized to the skin (morphea or linear scleroderma)
or may involve the skin and internal organs (systemic scleroderma).13 These
are discussed in detail in Chapter 206.
In systemic sclerosis, hardening of the skin
of the fingers and hands is accompanied by ulceration of the fingertips,
telangiectasia, and atrophy. Raynaud phenomenon is almost always present.
Facial involvement results in a taut appearance, with furrowing
of the skin around the lips and restricted opening of the mouth
Morphea is characterized by discrete areas of
skin hardening. The indurated plaques often have a distinct violaceous
border; atrophy, hypopigmentation, or hyperpigmentation may be present.
Linear scleroderma may occur in one or more
linear bands on the face (en coup de sabre) or over the length of
an extremity (Fig. 206-2 and eFig.
The prognosis for linear scleroderma is less favorable than for morphea,
because underlying musculoskeletal structures are often involved.
Hemiatrophy of affected areas can occur and may be severely disfiguring
and/or impair function of
the limb. Elevated antinuclear antibody titers and anti-single-stranded
DNA antibodies may be detected, especially during active disease. The
disease remits after 3 to 5 years. Physiotherapy is important to
limit joint contractures, and massage may be of benefit. Treatment
with prednisone in combination with methotrexate may halt progress
of the disease in some cases.14
Linear scleroderma on lower extremity.
Parry-Romberg syndrome is characterized by progressive
linear or hemifacial atrophy that develops in the presence of normal
or atrophic skin. Some children show mixed morphologies of linear
scleroderma and facial hemiatrophy; thus, Parry-Romberg syndrome
may be a variant of linear scleroderma. These patients may have
underlying intracerebral malformations or calcifications that result
in seizures or hemiparesis.
Atrophoderma is characterized by depressed areas
of skin that can be circumscribed (atrophoderma of Pasini and Pierini)
or linear (linear atrophoderma of Moulin). The lesions have a hyperpigmented,
bluish or violaceous color that resembles morphea, but there is
no sclerosis or induration. Large, circumscribed areas on the trunk
may be difficult to distinguish from morphea, and occasionally,
the 2 conditions coexist. Linear atrophoderma on the limbs can be mistaken
for linear scleroderma. The pathogenesis of this disorder is unknown. The
pathogenesis of atrophoderma is unknown. The histopathology is often
nonspecific with subtle changes such as thinning of the dermis,
edema, clumping of elastic tissue, and, occasionally, slight epidermal
atrophy. The disease has a prolonged course, and there is no effective treatment.
Atrophoderma should be distinguished from anetoderma, another condition
of unknown etiology, in which there is focal loss of dermal elastic
tissue. Lesions are characterized by small outpouchings of soft,
shiny skin. Anetoderma may be preceded by inflammatory papules or
plaques (the Jadassohn form), most common adolescent girls, or it
may arise de novo (the Schweninger-Buzzi form). Positive antiphospholipid
antibody titers are detected in some patients. Lesions tend to persist
indefinitely, and no therapy is of proven benefit.
Lichen sclerosus is an inflammatory disorder
of unknown etiology that not uncommonly affects the anogenital area of
prepubertal girls. In boys, the prepuce and glans penis are the sites
of predilection and may lead to phimosis or meatal obstruction (balanitis
xerotica obliterans). Affected females most often present with chronic
vulvar pruritus. They may also complain of dysuria or painful defecation
and constipation that result from perianal fissuring. The typical
clinical appearance is a white discoloration with atrophy of the
vulva and perianal area in a “figure-of-8” pattern.
The presence of purpura, telangiectasia, or erosions of the vulva
or perianal skin may lead to a mistaken diagnosis of sexual abuse.
Small hemorrhagic blisters may be misdiagnosed as hemangiomas (Fig. 362-4). Chronic lichen sclerosus may cause
adhesions and effacement of the labia minora and sometimes scarring.
Extragenital lichen sclerosus is very rare in childhood. The diagnosis
of genital lichen sclerosus is usually made clinically and rarely
requires a skin biopsy. The characteristic histopathologic finding
is a band of hyalinized collagen in the upper dermis. The course
of the disease is variable; in the majority of children it appears
to remit at or around puberty. Topical steroids are the most effective
treatment for vulvar and perianal
disease. A midpotency topical steroid or application of a high-potency
preparation for short periods is usually required.15 Surgical
intervention may be necessary for boys with phimosis or meatal narrowing.
There is no effective treatment for extragenital lichen sclerosus.
Vasculitis, the inflammatory destruction of blood vessels, occurs
in a variety of pediatric disorders and is classified by the size
of the affected vessels. When present, skin lesions may provide
an important clinical sign for diagnosis. Vasculitides are discussed
in more detail in Chapter 203.
Henoch-Schönlein purpura (HSP) is a
systemic leukocytoclastic vasculitis involving small vessels of
the skin, joints, gastrointestinal tract, and kidneys. Skin involvement
is usually the presenting sign with the development of “palpable
purpura” predominantly over the lower extremities and buttocks
(Fig. 203-1 and eFig. 362.2). Early
lesions may present as urticarial papules or plaques. The histopathology
of HSP shows perivascular neutrophils and their debris (leukocytoclasis),
fibrin deposition in vessel walls, and variable extravasation of
erythrocytes. The immunopathologic demonstration of IgA deposits within
vessel walls is diagnostic and may be found on nonlesional skin.
HSP in most children is self-limited and requires no treatment. Because
the onset of nephritis may follow that of the skin lesions by several
weeks, blood pressure and urinalysis should be monitored for at
least 1 month in all patients.
A variant of leukocytoclastic vasculitis seen in infants and
toddlers that resembles HSP is termed hemorrhagic edema
of infancy and is characterized clinically by annular erythematous
and purpuric plaques.16 Unlike HSP, it commonly affects the
face as well as the limbs and genitalia. Multiorgan disease is less
common than in older children with HSP. Nevertheless, these infants
should be evaluated for systemic involvement.
Small-vessel leukocytoclastic vasculitis, characterized clinically
by palpable purpura, is seen in a number of conditions other than
HSP and requires exclusion of collagen vascular diseases, infections,
and a drug reaction.
Polyarteritis nodosa (PAN) is a necrotizing
vasculitis of small and medium-sized arteries. Childhood PAN is
characterized by multisystem organ disease and the presence of painful
subcutaneous nodules. Livedo reticularis is a frequent association. Cutaneous
PAN, a milder variant predominantly affecting the skin, is often
preceded by streptococcal infection. Infantile PAN tends to involve
more selectively the coronary arteries and is sometimes accompanied
by a morbilliform eruption. This variant shares common features
with Kawasaki disease.