An international survey about nail histology processing techniques

Background There is limited data on nail histopathology techniques. The objective of this study was to examine nail histopathology techniques currently in use internationally. Methods An online survey was sent to the European Nail Society and Council for Nail Disorders during 2015–16. Results There were fifty seven respondents, from twenty countries comprising dermatologists, podiatrists and pathologists. Specimens were unmarked or marked using ink or a suture and fixed in 10% formalin, from 6 to 48 hours before embedding in paraffin wax (90% (17/19), liquid nitrogen (frozen section, 1/19) and 2-hydroxyethylmethacrylate (plastic, 1/19). Nail softening was undertaken by 71% (17/24) of respondents for 6 to 48 hours using Mollifex Gurr (12.5%, 3/24), 10% potassium hydroxide solution (12.5%, 3/24) or 10% potassium thioglycolate cream (12.5%, 3/24). Sections thickness was 4-9 µm (62.5%), using a steel microtome (92%,12/13) on glass slides (91.6%, 11/12). Hematoxylin and eosin (H&E) was routine for all biopsies and Periodic acid Schiff (PAS) (100%,15/15) for fungus The favored stain for differentiating melanin and hemoglobin was Fontana-Masson (60%, 6/10). For pigmented lesions, Melan-A was always employed by all respondents (9/9). Conclusion Nail histopathology processing has some small variations from normal skin processing.