Fatal Waterhouse-Friderichsen Syndrome caused by Streptococcus pneumoniae in a vaccinated adult with traumatic splenectomy: A case report.

Waterhouse-Friderichsen Syndrome (WFS) is a rare but life-threatening condition characterized by massive adrenal hemorrhage. WFS represents one of the features of the Overwhelming Post-Splenectomy Infection, which occurs any time after spleen removal and is recognized as the most serious complication in asplenic patients. We report a fatal case of WFS resulting from Streptococcus pneumoniae infection in a vaccinated and splenectomized patient. D.R., a 62-year-old man who had been splenectomized 20 years earlier following a traffic accident and had undergone Streptococcus Pneumoniae vaccination, had an acute febrile episode with chills at home, followed by vomiting. He died suddenly within 12 h of presentation. A multidisciplinary approach was adopted to resolve the case. Autopsy, histological, immunohistochemical, microbiological and toxicological examinations were performed. At autopsy, both adrenal glands presented increased volume and diffuse intraparenchimal hemorrhage. Postmortem bacteriological cultures of blood, cerebrospinal fluid and pericardial fluid showed S. pneumoniae, while serologic and molecular characterization demonstrated that the serotype responsible was serotype 23B, which was not included in the vaccination which D.R. underwent. Accordingly, the cause of death of D.R. was attributed to acute adrenal insufficiency due to Waterhouse-Friderichsen syndrome caused by Serotype 23B Streptococcus pneumoniae infection. In splenectomized patients with fever, accompanied by other nonspecific symptoms, the diagnosis of WFS should be considered, even if the subjects received the recommended vaccinations. The postmortem diagnosis of WFS requires a multidisciplinary approach, including macroscopic examination, histological analysis, and microbiologic investigations, so it is necessary to collect appropriate postmortem biological specimens for microbiological investigation.