Treating keloids with injections

Injecting keloids is one of the common treatment approaches. Outcomes and relapse rates are best if different agents are combined [1].

Three main injectable drug classes are often used in the treatment of keloids and hypertrophic scars: corticosteroids (CS), antimetabolites (e.g. 5-fluorouracil [5-FU]), and anti-tumour agents (e.g. bleomycin) [1,2]. Among other things, steroids suppress the inflammatory process, reduce the synthesis of collagen and glycosaminoglycans, and inhibit fibroblast growth [3].

The most commonly used CS is triamcinolone acetonide (TAC) in a dose of 10-40 mg/mL; but different treatment intervals are reported on in literature [3]. Used as monotherapy, CS are primarily efficacious in 50%-100% but show a substantial recurrence rate of 9%-50% [3]. In a comparison between TAC injections and 5-FU injections over 6 months, no statistical significance was found, but 5-FU had fewer local adverse events such as skin atrophy (TAC 44% vs 5-FU 8%) or telangiectasia (TAC 50% vs 5-FU 21%) [4]. Superior results were achieved by a combination of TAC/5-FU, which showed no recurrence at 6-months follow-up [5]. The combination may also have fewer adverse effects [3]. When tested against 5-FU, bleomycin had better data for efficacy and remission that were irrespective of age, sex, scar site, and duration of disease [6]. Recurrence rates for monotherapy with bleomycin were 0-15% [3]. Besides TAC and 5-FU, botulinum toxin A is currently being investigated and has been shown to modulate activity of keloids and hypertrophic scars by acting on expression of fibroblast and modulating their activity [7-10].

The injections themselves can be painful, but so can the administration of lidocaine [11]. “Benzyl alcohol in bacteriostatic saline is a preservative. It gives you 30 seconds of painless anaesthesia,” was the practice tip of Dr David M. Ozog (Henry Ford Hospital, USA). He advised a preload of bacteriostatic saline to be immediately followed by lidocaine into the centre of the saline. “You have to do it quickly,” Dr Ozog added. “You cannot inject the bolus of benzyl alcohol and then wait a little with the lidocaine - it has to be right there.”

1. 
   
   1. Dierickx C. 24th World Congress of Dermatology, 10-15 June 2019, Milan, Italy.
   2. Ogawa R. Int J Mol Sci. 2017;18: E606.
   3. Jones CD, et al. Dermatol Reports. 2015;7: 5880.
   4. Hietanen KE, et al. J Plast Reconstr Aesthet Surg. 2019;72: 4-11.
   5. Khan MA, et al. J Pak Med Assoc. 2014 Sep;64: 1003-7.
   6. Kabel AM, et al. J Dermatol & Dermatol Surg. 2016;20(1):32–38.
   7. Tretti Clementoni M. 24th World Congress of Dermatology, 10-15 June 2019, Milan, Italy.
   8. Austin E, et al. Dermatol Surg. 2018;44: 149-157.
   9. Gupta S. 24th World Congress of Dermatology, 10-15 June 2019, Milan, Italy.
   10. Kasyanju Carrero LM, et al. J Cosmet Dermatol. 2019;18: 10-15.
   11. Ozog DM. 24th World Congress of Dermatology, 10-15 June 2019, Milan, Italy.

 



Posted on 26 August, 201921 March, 2021