MMI133 Lecture Notes - Lecture 2: Gram Staining, Immunosuppression, Neisseria Meningitidis

• School: University of Alberta
• Department: Medical Microbiology and Immunology
• Course: MMI133
• Professor: Judy Gnarpe

Document Summary

Meninges are coverings of the brain and spinal cord (protect and enclose) (dura mater, 2 layers, Usually caused by microorganisms infecting the cerebral spinal fluid. One of the microbial causes of meningitis. Gram negative diplococcus, capsule important for disease. >12 serotypes based on capsule carbohydrates (polysaccharides or sugars) Only 4 subtypes called serotypes are responsible for most of the epidemics in the world (a,b,c, Droplet transmission (coughs, sneezes, saliva) (range 1 m) Co(cid:374)tai(cid:374)s (cid:862)endotoxin in the cell wall inflammation (los)(lipo-oligopolysaccharide) Endotoxin activates blood clotting, leads to dic (disseminated intravascular coagulation), hemorrhage (petichiae, purpura) and shock. Evades phagocytosis (being eaten) by white blood cells (due to presence of capsule) This (cid:271)a(cid:272)teriu(cid:373) is so(cid:373)eti(cid:373)es (cid:272)alled (cid:862)meningococcus (pl. meningococci)(cid:863) (cid:449)hi(cid:272)h is a (cid:374)i(cid:272)k(cid:374)a(cid:373)e for. Death if untreated: pressure to brain, influx of inflammatory cells (white blood cells) to csf (cerebral spinal fluid) if treated early has very good prognosis. Meningococcal sepsis (replication of bacteria in the bloodstream)