This may be a case of fungal infection, dermatitis or eczema. Contact dermatitis may present with redness, itchiness on a localized area of the body. This may be itchy. If the area continues to be itchy, an itch scratch cycle may ensue and this may lead to an eczematous skin condition. I suggest that you have this assessed by your doctor. You may need topical corticosteroids for these. Do not pick on the area and avoid resting your elbows on abrasive surfaces. Dust and heat may be causing these. I suggest that you have this assessed later on. Other differentials may be fungal infections and psoriasis.