Early Modulation of Systemic Inflammatory Indices During Propranolol Therapy in Infantile Hemangiomas

Background Propranolol is the first‐line systemic therapy for infantile hemangiomas (IHs). Beyond its vasoconstrictive and antiangiogenic effects, emerging evidence suggests immunomodulatory actions that may be reflected in systemic inflammatory indices derived from routine complete blood count (CBC) parameters. Objectives To evaluate short‐term changes in CBC‐derived inflammatory ratios—neutrophil‐to‐lymphocyte ratio (NLR), platelet‐to‐lymphocyte ratio (PLR), lymphocyte‐to‐monocyte ratio (LMR), systemic immune–inflammation index (SII), systemic inflammation response index (SIRI), and aggregate index of systemic inflammation (AISI)—in infants with IH treated with propranolol. Methods In this retrospective single‐center study, infants with IH received oral propranolol 1–2 mg/kg/day. CBC was obtained before treatment initiation (T 0 ) and after about 1 month (T 1 ). Ratios were calculated from neutrophil, lymphocyte, monocyte, and platelet counts. Of 155 treated children, inflammatory indices were available for 123 at T 0 and 74 at T 1 ; 65–66 patients had paired measurements. The normality of variables’ distribution was evaluated with the Shapiro–Wilk test. The differences in mean values of inflammatory factors between two moments (T 0 and T 1 , respectively) were analyzed with the paired t ‐test or the Wilcoxon signed‐rank test. Results Baseline median (interquartile range [IQR]) values were as follows: NLR 0.26 (0.23), PLR 62.92 (32.21), LMR 8.75 (4.95), SIRI 0.18 (0.21), SII 102.58 (83.01), and AISI 72.50 (86.45). After 1 month of propranolol therapy, PLR decreased significantly ( p = 0.002), while LMR increased significantly ( p = 0.02). NLR, SII, SIRI, and AISI demonstrated mild, nonsignificant downward trends. No hematologic toxicity was observed. Conclusions Propranolol therapy in infants with IH is associated with early, selective modulation of systemic inflammatory balance, most prominently reflected by reduced PLR and increased LMR. These readily available CBC‐derived ratios may reflect early biological response to propranolol and may complement clinical assessment in selected cases. However, these findings should be interpreted as exploratory and require prospective validation against standardized clinical outcomes.