Histologic, immunohistochemical, microbiological, molecular biological and ultrastructural characterization of pulmonary tularemia.

Tularemia is a rare zoonotic disease caused by Francisella tularensis, a Gram-negative bacteria. The clinical manifestations of pulmonary tularemia resemble those of other airways infections. Recently, a case of pulmonary tularemia was diagnosed at Tufts Medical Center. The purpose of the current report is to document the utility of applying several diagnostic tools, including immunohistochemistry, electron microscopy, microbiology and molecular biology in confirming the diagnosis of pulmonary tularemia, particularly in convalescing cases (up to 3 weeks postpresentation) and after antibiotic therapy. Our study demonstrates the usefulness of microbiological studies followed by morphological evaluation and the limitation of the molecular biology analysis of posttherapy samples.