If we had included patients with noninfectious systemic inflammatory response syndrome, we may have been able to explain our results more clearly and provide more support for the suggestion that there is an association of the homozygous MBL2 structural genotype (A/A) and the -550 genotype (H/H) with the progression from severe sepsis to septic shock. The gene discussed is MBL2; the disease is systemic inflammatory response syndrome.