title: Sporadic Legionnaires' disease. A pathologic study of 23 fatal cases.
abstract: Twenty-three fatal sporadic cases of serogroup 1 Legionella pneumophila pneumonia have been analyzed. Bilateral consolidating fibrinopurulent pneumonia was evident in most cases. In four leukopenic immunosuppressed subjects, and acute fibrinoserous pneumonia with a remarkable lack on inflammation was present. The bacterium was found at extrathoracic sites in 27% of the cases. Involvement of the spleen (25%), bone marrow (13%), and kidneys (4.5%) suggests that hematogenous spread of the infection is not uncommon. Involvement of the hilar lymph nodes in 44% of the cases, and multiple peripheral lymph nodes in one case, suggest that lymphatic vessels may also be an important pathway of dissemination. We concluded that systemic spread of L pneumophila is not uncommon in seriously ill patients and we believe that some of the unusual extrathoracic manifestations of this disease may be related to bacteremia.
mesh_terms: D000328:Adult; D000368:Aged; D001853:Bone Marrow / Q000473:pathology; D001921:Brain / Q000473:pathology; D005260:Female; D006801:Humans; D007668:Kidney / Q000473:pathology; D007875:Legionella / Q000648:ultrastructure; D007877:Legionnaires' Disease / Q000473:pathology*; D008099:Liver / Q000473:pathology; D008168:Lung / Q000473:pathology; D008297:Male; D008875:Middle Aged; D013154:Spleen / Q000473:pathology