Immunoglobulin deposition in skin of patients with lupus erythematosus: clinical correlates and indications for direct immunofluorescence.

LE is associated with deposition of immunoglobulins at the DEJ of both involved and uninvolved skin. A demonstration of these deposits by direct immunofluorescence can aid the clinician in establishing the diagnosis of LE, in separating between its types, and sometimes in gauging disease activity and prognosis. However, interpretation is not simple or straightforward. When the clinician receives the results, he or she must read the descriptive information as well as the immunopathologist's interpretation. The clinician must integrate this knowledge into the clinical setting to make a final interpretation. In addition to the immunofluorescence results, the clinician must consider the clinical status of the patient; the morphology, configuration, and distribution of skin lesions; the results of laboratory tests; and the results of biopsy for ordinary histopathologic examination. Despite these limitations, biopsy of skin for direct immunofluorescence examination is a very useful procedure that aids the clinician in the diagnosis and management of patients with various forms of LE.