Infection, stress and disease Patho

stages of infection

incubation→prodromal→invasion→convalesce

incubation stage of infection

from first exposure to onset of symptoms

prodromal stage of infection

initial mild symptoms

invasion stage of infection

invades further and affects other tissues

convalesce stage of infection

recovery occurs or disease becomes fatal

characteristics of pathogens

infectivity, pathogenicity, virulence, immunogenicity, toxogenicty, portal of entry and communicability

infectivity of pathogens

ability to invade and multiply

pathogenicity of pathogens

ability to produce disease

virulence of pathogens

ability to cause severe disease and potency

immunogenicity of pathogens

ability to produce immune response

toxogencity of pathogens

ability to produce toxins

portal of entry of pathogens

route to enter host

communicatability of pathogens

ability to spread person to person

endotoxin location

cell walls of gram neg bacteria

endotoxin release

during bacterial lysis

endotoxin effects

inflammatory, fever and endotoxic shock

endotoxin example

E coli

exotoxin release

during bacterial growth

exotoxin effect

damage cell membranes, activate second messenger

exotoxin example

C diff

types of vectors

mosquito, tick, flea, fly, snail

what disease do mosquitoes carry

malaria

what disease do ticks carry

Rocky Mountain spotted fever

what disease do fleas carry

leshimariasis

what disease do snails carry

sensitomiasis

what disease do flies carry

sleeping sickness

direct transmission

person to person

neutrophil function

attack, engulf and destroy bacteria to defend

neutrophilia

high neutrophil count

left shift

acute bacterial response in WBC count

fever pathway

infection→ cytokine stimulate PAF→high temp→fever

pryogens

exogenous and endogenous pathogens

cytokines

stress response and allostatic load

HIV mechanism

depletes T helper cells and weak immune regulation

antiretroviral therapy

3 or more drugs to slow disease progression, not cure

opportunistic infections (in relation to HIV)

cryptical meningitis, TB, pneumocytisis, thrush

general adaptation stages

alarm→resistance→exhaustion

alarm stage of GAS

body defense aroused, fight or flight, HPA axis and SNS activated

resistance stage of GAS

adaptation with cortisol, epinephrine and norepinephrine

exhaustion stage of GAS

compensatory mechanism break down when adaptation fails leading to allostatic overload

initiation of stress system

CNS and limbic system iniate stress response

HPA axis in stress system

hypothalamus release CRH

sympathetic nervous system in stress system

arousal, vigilance, anxiety and flight or flight

catecholamines in stress system

epinephrine and norepinephrine released during stress

effect of stress hormones on blood glucose

cortisol stimulates glucogenisis and raise BG

effect of stress someones on immune system

cortisol suppresses immune system leading to poor healing and increase risk of infection

effect of stress hormones on reproductive system

chronic stress dec sex hormones

long term stress effects on cardiovascular

chronic or dysregulated allostasis lead to CV disease

long term stress effects on bones

chronic or dysregulated allostasis lead to osteoporosis

long term stress effects on metabolism

chronic cortisol excess lead to metabolic syndrome, obesity and diabetes