CRP and Patent ductus arteriosus: Both ratios (NLR and MLR) were significantly higher in infants with PDA/CHD in comparison to infants with normal cardiac anatomy (p = 0.0319 and 0.0493, respectively; see Fig. 1 and Table 2), even though there was no significant difference in C-reactive protein levels between both groups (p = 0.1599 two-tailed test; Table 1).