What is the optimal site and biopsy technique for the diagnosis of oral mucosal autoimmune blistering disease?

BACKGROUND: The aim of this study was to determine which biopsy method produces the best diagnostic yield in patients presenting with autoimmune blistering diseases (AIBDs) of the oral mucosa. METHODS: This was a retrospective audit of patients who were biopsied at least once for a suspected AIBD of the oral mucosa. The type (incisional or punch) and site of biopsies were recorded in conjunction with case notes, electronic records and histopathological reports in order to calculate sensitivity, specificity and the method of biopsy which produced the superior diagnostic yield. RESULTS: A total of 125 biopsy samples from 66 patients were identified and reviewed. A diagnosis of AIBD was established in 49 (74%) patients. The chi-square test showed there was a statistically significantly higher (P = 0.0016) diagnostic yield using the punch biopsy technique compared to the scalpel method. The gingiva was the best biopsy site in terms of achieving a definitive diagnosis (P = 0.0001) regardless of the biopsy method used. CONCLUSIONS: A punch biopsy is more likely than scalpel biopsy to obtain a definitive diagnosis in patients presenting with a suspected oral AIBD. The gingiva is the optimal site to sample.