Mixed connective tissue disease characterized by speckled epidermal nuclear IgG deposition in normal skin

Four African female patients are described, who presented with the features of systemic sclerosis. Overlapping features of lupus erythematosus or dermatomyositis were present in three cases but were not prominent. Direct immunofluorescence of uninvolved skin revealed a particulate (or speckled) epidermal nuclear staining, with specificity for IgG. In view of the reported association between this finding and mixed connective tissue disease, these patients were treated with corticosteroids and marked improvement occurred in all cases. The usefulness of this investigation in making the distinction between systemic sclerosis and mixed connective tissue disease and in indicating a potentially effective form of therapy is discussed.