A study of spectrum of histopathological features in patients presenting with hyperpigmented skin lesions

Background: Pigmentary problems are one of the most frequent causes for dermatologic consultation. For accurate diagnosis, histopathological examination is useful. Pathologic examination often serves as a complementary or a confirmative part of the clinical diagnosis. Objective: To study the pattern of hyperpigmented skin lesions and their histopathological features. Materials and Methods: We prospectively studied histopathological features of hyperpigmented skin lesions in all age groups attending the dermatology department of a teaching hospital over a 2-year period. The skin lesions included inflammatory, genetic, metabolic, and endocrine lesions but excluded neoplastic, infectious, and developmental lesions. Results: Of the 980 skin biopsies, 200 (20.4%) were hyperpigmented lesions. Lesions were most common in the second and third decades. Clinically, itching was the most common presentation. Most common biopsy confirmed hyperpigmented lesions included classical lichen planus and its variants (55%). Histopathologically, most lesions showed lichenoid/interface dermatitis. Most hyperpigmented skin lesions were epidermal (75%) with lichen planus pigmentosus being the only dermal hyperpigmented lesion. Conclusion: Classical lichen planus was the most common hyperpigmented lesion seen in our study. Histopathological examination is useful in accurate diagnosis of hyperpigmented skin lesions, particularly in those with unclear or overlapping clinical features