A retrospective multicenter cohort study of differences in clinical characteristics of Infantile Hemangiomas in preterm and term infants: Prematurity increases risk of permanent cutaneous sequelae.

Background: We observed many preterm infants with unexpectedly thick infantile hemangiomas (IH), a subtype known to be associated with increased risk of scarring.

Objective: To compare the clinical features of localized IH in preterm versus term infants.

Methods: A retrospective study at three tertiary referral centers was conducted on 830 consecutive patients with localized IH.

Results: Preterm infants had a significantly higher incidence of superficial IH (75% in <33weeks, 57% in 33-<37 weeks, and 50% in term infants, p=0.007). Overall, their IH had thicker superficial components (p<0.001) and more stepped borders (p<0.001). These features correlated with the degree of prematurity. The average chronological age at presentation to the specialist was 5.6 (SD=6.2) months, with no difference between gestational age.

Limitations: The retrospective design and use of non-standardized clinical photographs. There may be biases introduced toward more severe IH types because the study sites were tertiary referral centers.

Conclusion: Preterm infants have features of IH that have obvious implication for systemic therapies. Most of these infants were seen beyond the typical proliferative phase when irreversible skin changes may have already occurred.