Accession Number : ADA167837


Title :   Pathogenesis of Cell Injury by Rickettsia conorii


Descriptive Note : Annual summary rept. no. 2, 11 Apr 1984-10 Apr 1985


Corporate Author : NORTH CAROLINA UNIV AT CHAPEL HILL


Personal Author(s) : Walker, David H.


Full Text : http://www.dtic.mil/get-tr-doc/pdf?AD=ADA167837


Report Date : 17 MAY 1985


Pagination or Media Count : 82


Abstract : This work was undertaken to determine the pathogenic mechanism by which Rickettsia conorii causes disease. R. conorii, an organism that has been neglected in spite of its widespread distribution and pathogenic qualities, was studied in human subjects, animal models, and in vitro. The purpose of the work is to elucidate the pathology of boutonneuse fever and the pathogenic mechanisms which might be blocked therapeutically or prophylactically. Human tissues were investigated by light microscopy, histochemistry, immunofluorescence, and electron microscopy. In vitro models of cell injury by R. conorii included the plaque model and cell culture release of lactate dehydrogenase. Of biopsies of lesions compatible with tache noires from 22 patients in Sicily, 16 have been documented as BF, 1 was shown not to have BF, and 5 have incomplete data at present. Evaluation of the documented cases semiquantitatively for presence and severity of specific pathologic feature yielded the following: cutaneous necrosis was present in 10 or 15 evaluatable taches noires; vasculitis was severe or moderate in all 16; thrombosis was severe in only 1, moderate in only 1, mild in 4, and absent in 10; dermal edema was moderate in 12, and mild in 4. The predominant leukocytes were lymphocytes and macrophages; immunofluorescent Rickettsia conorii were demonstrated in 12. Seven consecutive Sicilian patients with boutonneuse fever who consented to liver biopsy had hepatic lesions. Keywords: Ticks.


Descriptors :   *CELLS(BIOLOGY) , *PATHOGENESIS , *BACTERIAL DISEASES , *FEVERS , *RICKETTSIA , TISSUES(BIOLOGY) , MODELS , HUMANS , IN VITRO ANALYSIS , MICROSCOPY , ELECTRON MICROSCOPY , RELEASE , WOUNDS AND INJURIES , LIVER , IMMUNOASSAY , TICKS , CULTURES(BIOLOGY) , LYMPHOCYTES , LEUKOCYTES , LESIONS , VASCULAR DISEASES , NECROSIS , BIOPSY , SKIN DISEASES , HISTOCHEMISTRY , OXIDOREDUCTASES , TICKBORNE DISEASES , EDEMA , SICILY , THROMBOSIS.


Subject Categories : MEDICINE AND MEDICAL RESEARCH
      MICROBIOLOGY


Distribution Statement : APPROVED FOR PUBLIC RELEASE