Vitiligo: A common condition characterized by the loss of skin pigment cells, resulting in white patches. It is often the first consideration for white discoloration due to its prevalence and the distinct appearance of the patches.

Hypopigmentation due to injury or inflammation: Conditions such as pityriasis alba, post-inflammatory hypopigmentation, or discoid lupus erythematosus can cause white discoloration due to inflammation or damage to the skin.
Tinea versicolor: A fungal infection that can cause changes in skin pigmentation, leading to patches of lighter or darker skin, including white discoloration.
Idiopathic guttate hypomelanosis: A benign condition characterized by small, discrete, hypopigmented spots, often on the arms and legs.

Sarcoidosis: Although less common, sarcoidosis can cause skin lesions, including those with white discoloration. Missing this diagnosis could lead to delayed treatment of a potentially serious systemic disease.
Lichen sclerosis: A condition that can cause white, patchy skin that is thinner than normal, often in the genital area. It requires prompt diagnosis and treatment to prevent complications.
Leukoderma: A condition that can result from various causes, including burns, blisters, or infections, leading to white patches. Some forms can be associated with systemic diseases.

Piebaldism: A rare genetic disorder characterized by the absence of melanocytes in affected areas of skin and hair, leading to white patches and often hair loss.
Waardenburg syndrome: A genetic disorder that can cause hearing loss, changes in eye color, and patches of white skin or hair due to the absence of melanocytes.
Albinism: A group of rare genetic disorders that affect the production of melanin, resulting in little to no pigmentation in the skin, hair, and eyes.