Antimalarial lichenoid tissue reactions in patients with pre-existing lupus erythematosus

Drug-induced subacute cutaneous lupus erythematosus: evidence for differences from its idiopathic counterpart

BACKGROUND

Drug-induced subacute cutaneous lupus erythematosus (DI-SCLE) is a lupus variant with predominant skin involvement temporally related to drug exposure and resolving after drug discontinuation. It usually presents with annular polycyclic or papulosquamous eruptions on sun-exposed skin and shows serum anti-Ro/SSA antibodies.

OBJECTIVES

To address the question whether DI-SCLE differs significantly from idiopathic SCLE by virtue of clinical features.

METHODS

Ninety patients with SCLE seen in our departments from 2001 to 2010 were reviewed. Eleven of them diagnosed as having DI-SCLE were evaluated for type of skin lesions, systemic involvement, clinical course, and histopathological, direct immunofluorescence and laboratory findings. The cutaneous features were compared with those of the 79 patients with idiopathic SCLE.

RESULTS

The cutaneous picture was widespread in 82% of patients with DI-SCLE and in 6% of those with idiopathic SCLE [odds ratio (OR) 66·6, 95% confidence interval (CI) 11·2-394·9; P = 0·0001]. Bullous and erythema multiforme (EM)-like lesions were present in 45% of patients with DI-SCLE and in 1% of those with idiopathic SCLE (OR 65·0, 95% CI 6·5-649·6; P = 0·0001). Vasculitic lesions were observed in 45% of patients with DI-SCLE and in 3% of those with idiopathic SCLE (OR 32·1, 95% CI 5·1-201·7; P = 0·0001). Malar rash occurred in 45% of patients with DI-SCLE and in 6% of those with idiopathic SCLE (OR 12·3, 95% CI 2·8-54·9; P = 0·001). Visceral manifestations were excluded in all patients with DI-SCLE. Anti-Ro/SSA antibodies were found in all but one patient with DI-SCLE and disappeared after resolution in 73% of cases.

CONCLUSIONS

DI-SCLE differs from idiopathic SCLE by virtue of distinctive cutaneous features, particularly the widespread presentation and the frequent occurrence of malar rash and bullous, EM-like and vasculitic manifestations.

Lupus erythematosus: systemic and cutaneous manifestations

Skin and joint involvements are the most commonly occurring manifestations of systemic lupus erythematosus. There are 3 forms of cutaneous lupus: chronic cutaneous (discoid) lupus, subacute cutaneous lupus, and acute cutaneous lupus. Joint manifestations are usually not associated with warmth of the joints and may be only associated with pain and swelling. Painful or swollen joints respond rapidly to small or moderate doses of corticosteroids, whereas cutaneous manifestations usually respond to antimalarial drugs. Anti-Ro is associated closely with a photosensitive rash and with subacute lupus.

Subacute cutaneous lupus erythematosus: 25-year evolution of a prototypic subset (subphenotype) of lupus erythematosus defined by characteristic cutaneous, pathological, immunological, and genetic findings

Subacute cutaneous lupus erythematosus (SCLE) represents a widespread, photosensitive, nonscarring, nonindurated form of lupus erythematosus (LE)-specific skin disease. SCLE lesions are associated with a distinctive immunogenetic background including the production of Ro/SS-A autoantibodies. Individuals who have SCLE skin lesions as a component of their presenting illnesses represent a distinctive subset (subphenotype) of LE that enjoys a good prognosis with respect to life-threatening systemic manifestations of LE. SCLE skin lesions can be triggered by a number of different drugs the majority of which are capable of producing photosensitivity drug reactions in nonlupus patients. Single agent or combination aminoquinoline antimalarial therapy will suffice for 75% of SCLE patients. The remaining 25% will require other forms of systemic antiinflammatory therapy (e.g., diaminodipenylsulfone (Dapsone), thalidomide) or systemic immunosuppressive-immunomodulatory therapy. The etiopathogenesis of SCLE skin lesions is thought to result from four sequential stages: (1) inheritance of susceptibility genes (HLA 8.1 ancestral haplotype [C2, C4 deficiency, TNF-alpha-308A polymorphism], C1q deficiency); (2) loss of tolerance/induction of autoimmunity (ultraviolet light, photosensitizing drugs/chemicals, cigarette smoking, infection, psychological stress); (3) expansion/maturation of autoimmune responses (high levels of autoantibodies (Ro/SS-A), immune complexes, autoreactive T-cells); and (4) tissue injury/disease induction resulting from various autoimmune effector mechanisms (e.g., direct T cell-mediated cytotoxicity, antibody-dependent cell-mediated cytotoxicity).