MIC 4124 Study Guide - Midterm Guide: Epitope, Latency Stage, Eicosanoid
Document Summary
Complex organisms that have varied pathogenicity that includes humans, but also various other animals and can be free-living. Cell wall is rich in complex fatty acids. Consistent with gram-positive bacilli and heavily cross-linked peptidoglycan. Cell wall contains high levels of mycolic acid, lipo-arabinomanan, and arabinogalactan. Gram stain appears as ghost cells or as neutral. Primary tb under the age of 5 is likely to lead to death (immune system is not competent: latency / persistence, reactivation. Bacilli reach lower respiratory tract and are phagocytozed by alveoloar macrophages. Primary infection involves replication at the initial site of infection. They are eventually transported to local lymph nodes and results in dissemination to other sites (hematogenous = carried by blood) They survive in macrophages and transmit through the macrophage. Primary infection is almost always asymptomatic in adults. Disease in adults is usually a consequence of reactivation of latent infection. With activation of immune response, primary infection may be controlled.