NURS 3110 Lecture Notes - Lecture 7: Streptococcal Pharyngitis, Necrotizing Fasciitis, Rheumatic Fever
Document Summary
The cocci of medical importance, gram + cocci. Identify key modes of transmission and associated approaches to prevention. Contrast different strains and symptoms associated with infection. Overview: essential characteristics, cocci in chains, gram + (stain blue or purple, catalase negative (don"t bubble in h2o2, antigenic structure, group specific cell wall structure. Basis of serologic grouping - lancefield grouping (different strains) Different strains of strep, carbohydrate capsule changes. Often forms capsule on exterior of envelope and slime layer, contribute to virulence, keep vegetative cells viable. Reduces risk of phagocytosis: m protein. Major virulence factor of group a strep. May play role in the pathogenesis of rheumatic fever, cross-reactive antigens w/ cardiac tissue. Classification of streptococci: hemolysis (lysis of rbcs, alpha - partial hemolysis (green, beta - complete hemolysis (clear, gamma - no hemolysis, plate different strep organisms: can initiate different hemolysis, different hemolysis patterns specific to different organisms, ex.
