S100A4 and incontinentia pigmenti: In the univariable analysis, high S100A4 level, (odds ratio [OR] 21.39; 95% CI 4.67–98.64; P < 0.001), male (P = 0.010), low %VC (≤ 80%) (OR 4.21; 95%CI 1.46–12.20; P = 0.008), high KL-6 (≥ 1000) (OR 4.81; 95%CI 1.43–16.26; P = 0.011), and operative time (OR, 1.01; 95%CI 1.00–1.02; P = 0.048) were significant predictive factor of AE of IP.