The white pulp in the setting of the septic spleen caused by different bacteria: a comparative morphometric study

In the past little attention has been paid to histomorphologic changes accompanying the phenomenon of the septic spleen, thus indirectly reinforcing the old axiom that the spleen is an organ of mystery. It is especially noteworthy that the relationship between different causative bacteria and histopathologic abnormalities of the white pulp has not been investigated. In this study morphometric analysis was performed on the white pulp of 30 spleens obtained at autopsy from individuals with premortal sepsis. A strictly defined age- and sex-matched control group was analyzed for statistical comparison. Our findings demonstrate a significant depletion of B- and T-areas in the septic spleen, accompanied by a significant tendency towards reactive germinal center hyperplasia regardless of the type of bacteria responsible. However, depletion of splenic B-areas was shown to be significantly pronounced in the setting of premortal enterococcemia in comparison with a panel of gram-negative flagellated bacteria. It is felt that certain bacterial virulence factors (e.g. flagellation and/or structural components of the cell wall) might be pathogenetically involved in the observed changes, reflecting a partially different activation of splenic lymphocytes in the setting of the septic spleen.