Direct Immunofluorescence

Abstract

Direct immunofluorescence (DIF) is a valuable diagnostic tool in the dermatology clinic. The proper use of a biopsy for DIF is dependent on several factors, including appropriate clinical indication, correct clinical site selection, and proper specimen handling and transport. Improper use of DIF can lead to false negatives, decreased diagnostic yield, and poor resource utilization. This article provides instruction on the appropriate indications and biopsy site selection for DIF. Three examples of skin diseases in which DIF would be particular useful when making a diagnosis are provided.

Figure 1.

Biopsy site selection for blistering diseases

Figure 2.

Biopsy site selection for vasculitis

Figure 3.

Biopsy site selection for connective tissue disease

Figure 4.

Numerous erythematous bullae of varying sizes—Blue circles indicate possible biopsy locations for hematoxylin & eosin; the green circle indicates a possible biopsy location for direct immunofluorescence.