White spots on the skin can happen due to various other reasons. They can be as simple as a sun induced sun allergy or it can be because of dryness what we call as pityriasis alba or it can be because of fungal infections like pityriasis versicolor or it can happen in infections like leprosy where the patches can happen not only on the exposed parts but also on the covered parts. Sometimes they can also be because of some allergic reactions like pityriasis lichenoides chronica or some other conditions. Mycosis fungoids is a cutaneous T cell lymphoma which involves usually the covered parts of the body. Even though it is a very mild condition you can’t ignore it. Many a times white spots can happen in arms and legs especially of the elderly because of age related change which is called idiopathic hypomelanosis. So depending on the condition the reasons for white spots are varied. So we need to look into what exactly is happening, what is the distribution of the lesion and the clinical presentation. The most common investigation is dermatoscopic examination wherever we get a better picture of these white spots where in we do a skin biopsy and check into what reactions are happening inside the skin and these most often help us to reach a diagnosis. If the diagnosis is confirmed the treatment is much more easier.
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