Globular deposits of immunoglobulins and complement in the papillary dermis. Clinical significance

Globular deposits of immunoglobulins in the papillary dermis have been reported to occur in certain dermatoses, particularly in lichen planus. The clinical correlation of these deposits in 52 skin biopsy specimens reviewed by light and fluorescent microscopy was studied. These cases included five of lichen planus, 24 of lupus erythematosus or related diseases, four of dermatitis herpetiformis, three of drug eruption; two each of bullous pemphigoid, erythema nodosum, porphyria cutanea tarda; one each of vitiligo, pyoderma gangrenosum, neurodermatitis, erythema multiforme, granuloma annulare, vasculitis, epidermolysis bullosa simplex, Rothmund-Thompson syndrome, and four of unspecified dermatoses. Using an arbitrary scale of 1-4 based on the frequency of deposits, 3+ and 4+ deposits were identified in all five cases of lichen planus, as well as in six cases of lupus erythematosus, one of drug eruption, one of bullous pemphigoid, one of erythema nodosum, the vitiligo, vasculitis, and Rothmund-Thompson syndrome cases, and two cases of unspecified dermatoses; other cases showed only 1+ and 2+ deposits. In all five cases of lichen planus, the deposits contained IgM and C3, and in addition, IgA was present in four, IgG and fibrinogen in three. Among non-lichen planus cases, C3 was detected in 11 of 49, and fibrinogen in only four of 49. These findings indicate that globular deposits of Ig in the dermis, though suggestive, are not pathognomonic of lichen planus.