Nail disorders are prevalent dermatologic complaints and present at any age. 50% of the nail disorders were due to infectious causes, 15% were due to metabolic or inflammatory causes, and 5% were due to pigment disturbances and malignancies. The differential diagnosis of nail disorders is still often a field of incertitude. 1 Clinical evaluation is still an issue in such cases. The nail unit is a greatly specialized structure and there are significant histopathological variations within its components. SO, the mycological assessments, and histopathological examinations are pivotal for the diagnosis of different nail disorders. 1 Two factors can hinder a precise diagnosis of nail disorders. The first factor is that several nail disorders may clinically mimic one another, leading to difficulty in diagnosis. From a practical view, one may consider infectious, inflammatory, and neoplastic processes in the differential diagnosis of a single lesion. So, a biopsy is usually resolve the cell layer that is abnormally found in the nail bed or nail matrix, and it is normally found in the nail fold or hyponychium. 2 The nail biopsy is an essential technique to obtain an accurate diagnosis of clinically ambiguous nail diseases that is not diagnosable by history, clinical examination, and mycology testing , 3 but it is disagreeable with the patient and may lead to scarring and disfigurement of the nail. 4

Objective: This study aimed to assess the possible role of dermoscopy in the diagnosis of different nail disorders compared with the clinical and histopathological diagnosis. Methods: This study included 104 patients with any nail disorders of both sex and any age. All the patients were subjected to a detailed medical history taken, clinical general examination, clinical and dermoscopic examinations of 20 nails. Potassium hydroxide examination was used to examine all patients with suspicious of onychomycosis. Histopathological evaluation was used to examine of clinically ambiguous nail disorders. Results: The most common nail diseases were onychomycosis (54.81%) followed by nail psoriasis (19.2%), and nail lichen planus (3.8%). Conclusion: Clinical evaluation was an important in diagnosis of different nail diseases. Nail dermoscopy could confirm clinical diagnosis and help in getting an accurate diagnosis of nail diseases and guide in the management of nail diseases by permitting better visualization of nail structure and pathology. Histopathological examination provided the most definitive method in reaching an accurate diagnosis due to it could provide etiologic, diagnostic, and prognostic information. There was good agreement between clinical, dermoscopic, and histopathological examinations for accurate diagnosis of different nail diseases.