A study of the clinico-histopathological features of erythematous tender nodules predominantly involving the extremities

Background: Erythematous tender nodules predominantly involving extremities are frequently encountered in dermatology and rheumatology practice. They are diagnosed based on distinct clinical and histopathological features. However, in clinical situations, considerable overlap is observed that poses a diagnostic challenge. We undertook a study on clinico-histological patterns of inflammatory nodules over extremities. Methods: After detailed history and examination, a preliminary clinical diagnosis was made in 43 cases, followed by skin biopsy from representative nodules. Histological diagnosis made was correlated with clinical features. Results: Of 43 cases, a single clinical diagnosis was made in 25 (58.5%) cases while in the remaining cases more than one diagnosis was considered. On correlating with the histopathological diagnosis, concordance was observed in 51% cases while the remaining showed either histological discordance with clinical diagnosis (14% cases) or were kept in the undecided category (35% cases). Conclusion: Considerable clinico-histological overlap was observed in inflammatory nodules over extremities. Histopathology alone was not helpful in differentiating one entity from another at all times since variable histo-pathological patterns were seen.