Microneedle delivery of botulinum toxin type A combined with hyaluronic acid for the synergetic management of multiple sternal keloids with oily skin: A retrospective clinical investigation.

[BACKGROUND] For the treatment of sternal keloids, corticosteroid therapy has side effects including abnormal sebum secretion and acne. Relapse of keloids is common after corticosteroid injection in patients with oily skin. To reduce side effects and keloid recurrence, we used a combination of botulinum toxin type A (BTX-A) and hyaluronic acid (HA) as synergetic management for multiple sternal keloids in patients with oily skin.

[METHODS] In total, 58 patients with multiple sternal keloids who received monthly steroid injections were retrospectively included. Thirty-two patients in the intervention group received an additional injection of BTX-A/HA on the same day as the first injection of the steroid, while the remaining 26 patients were treated as the control group. At baseline and follow-up visits, sebum production and transepidermal water loss (TEWL) were assessed as primary outcomes, and the Vancouver Scar Scale (VSS) score, keloid recurrence, visual analog scale (VAS) score, and patient satisfaction were assessed as secondary outcomes.

[RESULTS] In the control group, average sebum production and TEWL were increased to 132% and 104% of baseline, respectively, at the 24-week follow-up. In the intervention group, average sebum production and TEWL reached nadir at the 8-week follow-up and then increased to 96% and 91% of baseline, respectively, at the 24-week follow-up. Sternal keloid relapse was observed in 88.5% of the patients in the control group and none of the patients in the intervention group. The total VSS score at 24 weeks was 11.04 ± 0.14 and 8.93 ± 0.26 (p < 0.001) in the control group and intervention group, respectively, and the VAS score was 75 ± 5.10 and 19.14 ± 3.80 (p < 0.001) in the control group and intervention group, respectively. Higher patient satisfaction was reported in the intervention group.

[CONCLUSIONS] Microneedle delivery of BTX-A/HA decreases sebum production while improving skin barrier function. Thus, this combined therapy can relieve the side effects of corticosteroid therapy and reduce keloid recurrence.