NGF and keloid: Less used are the following therapeutic strategies, in used for specific disorders, such as ARA290, an erythropoietin derivate for sarcoidosis SFN [45], recombinant human nerve growth factor for diabetic SFN [5], propranolol for SFN related to aquagenic pruritus [9], plasma exchange therapy for complex regional pain syndrome [6], enzyme replacement therapy for Fabry related SFN [17,35], botulinum toxin type A for keloid [38].