Histomorphological Study of Nail Changes in Various Dermatoses — An Understudied Entity in Dermatopathology

Background: The nail is our most versatile tool and serves a very important function of protecting the distal phalanx. The nail unit shows specific changes that are markers for a wide range of local and systemic conditions. Objectives: The objectives of the study are to identify the spectrum of histomorphological features in various nail lesions and to highlight the role of histopathology in diagnosis of nail diseases. Methods: This is a descriptive study done over a period of 18 months. The nail biopsy specimens were received in 10 % formalin, softened with 10% nitric acid, processed and stained with routine Hematoxylin & Eosin [H&E] stains. Periodic Acid stain[PAS] stain was done wherever necessary. Histopathological examination by light microscopy was done to arrive at a precise diagnosis. Brief patient history and clinical features were also noted. Results: A total of 50 nail punch biopsies were examined. Psoriasis was the most common accounting for 38%. The combined approach of H & E and PAS stain was helpful in diagnosis of onychomycosis in 24%. Pigmentary disorders (14%) , lichen planus (10%) and alopecia areata (6%) were the other conditions observed. In 8% of cases microscopic features were nonspecific. Conclusion: The nail unit has a complex morphology with many peculiarities. Though it is quite accessible, it remains understudied. Histomorphological evaluation of nail punch biopsy is useful in understanding the involvement of nail in various dermatoses and also aids in the accurate diagnosis. Keywords: Dermatoses, Histopathology, Nail biopsy