SALT SPLIT TECHNIQUE: A USEFUL TOOL IN THE DIAGNOSIS OF SUBEPIDERMAL BULLOUS DISORDERS

BACKGROUND: Direct immunofluorescence (DIF) is the gold standard in the diagnosis of immunobullous diseases. However, it cannot reliably differentiate various subtypes of subepidermal immune- bullous diseases (SIBD). Salt split technique (SST) could be used under such circumstances to differentiate them. There is paucity of reports in the Indian literature regarding the SST. AIM: This study was designed to evaluate the utility of direct SST in subepidermal blistering diseases. MATERIALS AND METHODS: Fourteen clinically diagnosed cases of subepidermal blistering diseases were included in the study. Two perilesional punch biopsies were taken one each for DIF and salt split study. RESULTS: Linear basement membrane zone band with IgG and/or C(3) was seen in 14 cases of patients BP. Salt split study showed epidermal or mixed pattern of deposits in 12 patients and exclusive floor pattern in two patients. The diagnosis was revised in these two patients to epidermolysis bullosa acquisita. CONCLUSION: SST is a simple, inexpensive procedure and should be routinely employed in the diagnosis of subepidermal bullous diseases.