Intralesional Corticosteroids: Technique and Indications

Overview / Definition Intralesional corticosteroids (ILCs) are a form of localized treatment where corticosteroids are injected directly into a lesion. This method allows for a higher concentration of the medication to be delivered directly to the site of inflammation, reducing systemic side effects and providing rapid therapeutic benefits. Epidemiology ILC therapy is commonly employed in dermatology for a variety of skin conditions. It is frequently used for: Psoriasis Alopecia areata Keloids and hypertrophic scars Dermatitis Granuloma annulare Epidemiological studies suggest that conditions like alopecia areata can affect up to 2% of the population, highlighting the importance of effective localized treatments. Pathophysiology / Mechanism Corticosteroids exert their effects by modulating the immune response and reducing inflammation. They inhibit the activity of inflammatory cells, such as macrophages and lymphocytes, and decrease the production of inflammatory mediators such as cytokines. In keloids and hypertrophic scars, ILCs help to reduce collagen synthesis and promote apoptosis of fibroblasts, leading to improved cosmetic outcomes. Clinical Presentation The clinical presentation of conditions treated with ILCs varies: Alopecia areata: Patchy hair loss on the scalp or body. Keloids: Raised, thickened scars that extend beyond the original wound. Psoriasis: Well-defined erythematous plaques with silvery scales. Dermatitis: Erythematous, itchy lesions often associated with an allergic or irritant trigger. Granuloma annulare: Annular plaques that may be skin-colored or erythematous. Diagnosis / Workup Diagnosis of conditions treated with ILCs is primarily clinical, but may involve: Patient history and physical examination. Skin biopsy if the diagnosis is uncertain or for atypical presentations. Patch testing for suspected contact dermatitis. Treatment / Management The technique for administering ILCs involves: Using a 1- to 5-mL syringe with a 27- to 30-gauge nee