IFIH1 and incontinentia pigmenti: In comparisons of the IP death group versus the survivor group, the anti-MDA5-Ab-positive rate was significantly higher (80% vs. 14%; P = 0.0002), the anti-ARS-Ab-positive rate was significantly lower (0% vs. 56%; P = 0.0024), and the serum levels of LDH, ferritin, and LRG were significantly higher (P = 0.011, 0.0008, and 0.026, respectively).