Hot Spots, also called acute moist dermatitis, are irritated patches of skin that result from an initial irritation but develop into something much worse by a bacterial infection. The most common places where hot spots form on your dog's neck, hips, head or limbs. The red, moist patches can become very painful and cause oozing, scabbing, matted fur, and loss of fur at the affected area. While hot spots are usually localized to a specific area, treatment must focus on the underlying cause.