Postmortem diagnosis of sepsis: a preliminary immunohistochemical study with an anti-procalcitonin antibody

Post mortem diagnosis of sepsis, especially in the forensic field, is a problem that presents several difficulties. The pathological findings in sepsis are often nonspecific, as they are often compatible with other different clinical pictures. The sensitivity of procalcitonin for the diagnosis of sepsis is estimated approximately in 77% while its specificity is about 79 %. Those characteristics suggested us that procalcitonin could be a possible immunohistochemical marker in the pathological diagnosis of sepsis. We selected 10 cases by the presence of clinical data that could sustain and underlie a certain diagnosis of sepsis. The positive control has been a thyroid gland without pathological alterations. The negative control has been on 5 subjects dead from non-infective causes. In all the samples we found the reaction with the anti-procalcitonin antibody to be positive in blood vessels. In every case we analyzed a definite positivity inside the cytoplasm of the myocardial cells, in brain cells (astrocytes and microglial), in the myelomonocyte line and inside the pneumocytes. In addition inside the cardiomyocytes it has also highlighted a nuclear positivity. In the liver tissue we found a clear positivity in hepatocytes, in the ductal epithelium and in the portal-biliary space. In the kidney tissue samples we found the antibody in glomeruli and in renal tubules. In conclusion we believe that immunohistochemical study with an anti - antibody procalcitonin can be a valuable aid for the postmortem diagnosis of sepsis. The small number of cases that we studied represent a limitation for our research.