Infections and ABO Blood Groups in Burn Patients.

Background: Lack of isohemmaglutinins may predispose individuals to infection. The purpose of this study was to determine if there was a relationship between infections and burn patient blood groups.

Methods: This was a retrospective review of burn patient data on infections and ABO blood groups between March 1999-May 2004. Chi-square and Mann-Whitney U with one-way ANOVA statistical analyses were performed.

Results: There were 1615 burn admissions; 794 patients were typed for blood groups; 179 patients received blood transfusions. Of the study population, African-Americans constituted 59%, Hispanics 21%, Caucasians 16%, and others 4%. Although age (mean±se: 37±2 years), % TBSA (11±2%), and inhalation injury (15%) were similar in all groups, patients with B blood group had longer BICU stays compared to the O blood group, p<0.01. There was no statistically significant difference among the blood groups in the number of nosocomial wound infections, episodes of sepsis, bacteremia, urinary tract infections (UTIs) or pneumonia. The bacterial etiology was similar in all blood groups without any species preponderance. Transfused patients had a higher frequency of infections compared to those who were not transfused and significance was only reached in the comparison for UTIs, p=0.02.

Conclusions: Our data shows that burn patients with B and AB blood groups did not have an increased frequency of infections compared to the patients with A and O blood groups. Burn patients were immunosuppressed as part of their injury. Those who received transfusions probably had a further perturbation of their immune system, since blood products cause immunosuppression. Other factors such as inhalation injury and %TBSA also predisposed burn patients to infection. Transfusions rather than blood groups were associated with an increased number of nosocomial UTIs in burn patients.