Track

Abstract

A 73-year-old white male with no systemic symptoms presented to a dermatology clinic with a small, pink papule on the arm, which was biopsied to rule out non melanoma skin cancer. Hematoxylin and eosin (H&E) demonstrated granulomas with neutrophilic inflammation within and around the granulomas. The initial H&E also had focal clear areas within granulomas with minute debris and associated neutrophils, findings suspicious for an atypical mycobacterial infection. Initial and repeat acid fast bacilli (AFB) stains were negative. However, the clear areas with debris seen on the initial H&E were not present on these AFB stains or on intervening H&E levels. After digitally scanning the initial H&E, the decision was made to destain the initial H&E with a 5% acid water solution and then perform an AFB stain on that slide. AFB staining of the destained slide positively stained the suspicious debris in these clear areas within the granulomas. This case demonstrates the feasibility of destaining H&E-stained slides if another study is needed and tissue conservation is essential or findings are focal. The implications of this approach include improved tissue preservation and successful diagnosis in cases involving minute, focal, or otherwise difficult-to-detect organisms, cancer foci, or other pathologies.