Low levels of mannose-binding lectin at admission increase the risk of adverse neurological outcome in preterm infants: a 1-year follow-up study

Mannose-Binding Lectin Levels in Late-Onset Sepsis in Preterm Infants: Results from a Prospective Study in a Tertiary Care Center

Introduction: This study aimed to determine the association between serum mannose-binding lectin (MBL) levels, gene polymorphisms and late-onset sepsis (LOS) in preterm infants. Methods: Infants with <37 gestational weeks were categorized into two groups according to the presence of LOS during their hospitalization. An MBL level <700 ng/ml was defined as deficiency, <400 ng/ml as severe deficiency. Codon 54 and 57 polymorphisms of MBL2 gene were analyzed. Results: Overall, 153 preterm infants were included. MBL deficiency was found to be more common in the LOS group (p = 0.02). The rate of Gram-negative sepsis was higher in MBL2 variant-type (p = 0.01). In the logistic regression analysis, MBL levels <700 ng/ml were found to have a significant effect on LOS development (odds ratio: 2.692, 95% confidence interval 1.196-5.8, p = 0.02). Conclusions: MBL deficiency is an important risk factor for the development of LOS. Furthermore, there is an association between MBL2 gene polymorphism and Gram-negative sepsis.

Mannose-binding lectin gene polymorphism and its effect on short term outcomes in preterm infants

OBJECTIVE

Mannose-binding lectin, which belongs to the collectin family, is an acute-phase reactant that activates the complement system. This study aimed to investigate the effect of MBL2 gene polymorphism on short-term outcomes in preterm infants.

METHOD

Infants of <37 gestational weeks who were admitted to the neonatal intensive care unit during a two-year period were enrolled in this prospective study. The neonates were categorized into two groups according to their MBL2 genotypes. Normal MBL2 genotype was defined as MBL2 wild-type (AA genotype), whereas mutant MBL2 genotype was defined as MBL2 variant-type (AO/OO genotype). The relationship between MBL2 genotype and short-term morbidity and mortality was evaluated.

RESULTS

During the two-year study period, 116 preterm infants were enrolled in this study. In MBL2 variant-type, mannose-binding lectin levels were significantly lower and incidences of mannose-binding lectin deficiency (MBL level<700ng/mL) were higher (p<0.001). In this group, the prevalence of respiratory distress syndrome and mortality was significantly higher (p<0.001, p=0.03 respectively). In the MBL2 wild-type group, the prevalence of necrotizing enterocolitis (NEC) was higher (p=0.01). Logistic regression analyses revealed that MBL2 variant-type had a significant effect on respiratory distress syndrome development (odds ratio, 5.1; 95% confidence interval, 2.2-11.9; p<0.001).

CONCLUSIONS

MBL2 variant-type and mannose-binding lectin deficiency are important risk factors for respiratory distress syndrome development in preterm infants. Additionally, there is an association between MBL2 wild-type and NEC. Further studies on this subject are needed.

Autosomal dominant mannose-binding lectin deficiency is associated with worse neurodevelopmental outcomes after cardiac surgery in infants

OBJECTIVES

The MBL2 gene is the major genetic determinant of mannose-binding lectin (MBL)-an acute phase reactant. Low MBL levels have been associated with adverse outcomes in preterm infants. The MBL2_Gly54Asp missense variant causes autosomal dominant MBL deficiency. We tested the hypothesis that MBL2_Gly54Asp is associated with worse neurodevelopmental outcomes after cardiac surgery in neonates.

METHODS

This is an analysis of a previously described cohort of patients with nonsyndromic congenital heart disease who underwent cardiac surgery with cardiopulmonary bypass before age 6 months (n = 295). Four-year neurodevelopment was assessed in 3 domains: Full-Scale Intellectual Quotient, the Visual Motor Integration development test, and the Child Behavior Checklist to assess behavior problems. The Child Behavior Checklist measured total behavior problems, pervasive developmental problems, and internalizing/externalizing problems. A multivariable linear regression model, adjusting for confounders, was fit.

RESULTS

MBL2_Gly54Asp was associated with a significantly increased covariate-adjusted pervasive developmental problem score (β = 3.98; P = .0025). Sensitivity analyses of the interaction between age at first surgery and MBL genotype suggested effect modification for the patients with MBL2_Gly54Asp (P_interaction = .039), with the poorest neurodevelopment outcomes occurring in children who had surgery earlier in life.

CONCLUSIONS

We report the novel finding that carriers of MBL2_Gly54Asp causing autosomal dominant MBL deficiency have increased childhood pervasive developmental problems after cardiac surgery, independent of other covariates. Sensitivity analyses suggest that this effect may be larger in children who underwent surgery at earlier ages. These data support the role of nonsyndromic genetic variation in determining postsurgical neurodevelopment-related outcomes in children with congenital heart disease.