Ehrlichia chaffeensis

Small obligate, intracellular coccobacillus that infects monocytes. Epidemiology: 1) reservoir of Ehrlichia chaffeensis are deer, dogs & goats 2) vectors of Ehrlichia chaffeensis are ticks: - Amblyomma americanum (Lone Star tick) 3) Ehrlichia chaffeensis is endemic in the same areas where Rickettsia rickettsii (etiologic agent of Rocky Mountain spotted fever) is found. Pathology: - infects monocytes - etiologic agent of ehrlichiosis Laboratory: - Ehrlichia chaffeensis antigen - Ehrlichia chaffeensis serology - Ehrlichia identified by light microscopy - staining of peripheral blood neutrophils & monocytes for morula or loose aggregrates of bacteria within monocytes - Ehrlichia chaffeensis DNA - Ehrlichia chaffeensis groEL gene

Properties

KINGDOM: monera DIVISION: SCHIZOMYCETES

References

- Medical Knowledge Self Assessment Program (MKSAP) 11, 15, American College of Physicians, Philadelphia 1998, 2009