Internal Medicine

0521779407-C04 CUNY1086/Karliner 0 521 77940 7 June 14, 2007 20:37

442 Cutaneous Lupus Erythematosus (LE)

variable-size that usually develop one or more of the following fea-

tures over time: keratotic follicular plugging; hyperpigmentation at

the outer borders of lesions; hypopigmentation, telangiectasia and

atrophic scarring at the center of lesions. Focal, scarring alopecia

with scalp involvement.

➣All – red skin lesions, sun-exposed distribution

tests

Basic Blood Tests

■ACLE – positive ANA, elevated ESR, anemia, leukopenia, thrombocy-

topenia, hypocomplementemia, abnormal renal function, increased

serum globulins, anti-phospholipid autoantibodies.

■SCLE – positive ANA, Ro/SS-A (can be present in absence of ANA)

■DLE – ANA is usually negative, but with human substrates low titers

are possible

Basic Urine Tests

■ACLE – proteinuria, hematuria, cellular casts

■SCLE – usually normal

■DLE – normal

Specific Diagnostic Tests

■ACLE – double-stranded DNA and Sm autoantibodies

■SCLE – Ro/SS-A and La/SS-B autoantibodies

■DLE – none

Other Tests as Appropriate

■All – lesional skin biopsy (routine H&E examination) of skin

reveals LE-specific skin disease pattern known as an interface

dermatitis

■All – lesional skin biopsy (direct immunofluorescence examination)

for selected patients in whom diagnosis is in question

differential diagnosis

■ACLE – dermatomyositis, acne rosacea, seborrheic dermatitis, pho-

toallergic or phototoxic drug eruptions

■SCLE – polymorphous light eruption, photosensitive psoriasis, ery-

thema annulare centrifugum and other annular reactive skin disor-

ders

■DLE – granuloma faciale, sarcoidosis