In summary, our results suggest no association between MBL deficiency in the Colombian children and their observed increased frequency of pneumococcal infections.This is in agreement with a study showing that variant mannose binding alleles are not associated with susceptibility to invasive pneumococcal infection in randomly selected adult Danish patients. 8A study comparing the frequencies of alleles B, C, and D of MBL and a functional promoter polymorphism at -221 (X/Y variant) with invasive pneumococcal diseases in adults, reported that those homozygous for mutations of MBL who had low MBL serum concentrations, may be at increased risk of acquiring pneumococcal infections (Odds Ratio 2.6). 9However, a definitive study that considers analysis of concomitant primary immunodeficiencies and epidemiological data on pneumococcal infections in children between 6 and 18 months of age, who seem to be the more susceptible to invasive pneumococcal infections, is still needed. 10