immune system Flashcards
physical barriers of protection
skin mucous, cilia
chemical barriers of protection
saliva, stomach acid
mechanical barriers of protection
cell turnover, mechanical cleansing, low skin temperature
cellular barriers of protection
lymphocytes, granulocytes
innate immune system
inbuilt, doesn’t need to be learned- involves the actions of physical, chemical, some cellular barriers and inflammation response
adaptive immune system
specific, involves the action of lymphocytes to produce a specific antibody response to the invading pathogen
skin
impermeable barrier, secretes anti-microbial peptides to kill unwanted pathogens
cilia
vibrate to push mucous up to the oesophagus, mucous traps invading pathogens (mucociliary escalator)
mechanical cleansing
removal of old or damaged cells from the skin surface
low skin temperature
creation of an inhospitable environment for growth of many pathogens
saliva
contains lysozymes, which can break down the cell wall of bacteria.
contains immunoglobin, which can attach to an invading pathogen and inhibit its function
stomach acid
extremely low pH, makes it an inhospitable environment for pathogens
functions of inflammation
limits the spread of infection, prevents further damage, removes harmful agents
functions of cell-mediated immunity
- destruction of pathogens by white blood cells
- destruction of the bodies infected cells by T cells
- release of cytokines
primary organs of the immune system
bone marrow and the thymus
secondary organs of the immune system
lymph nodes, spleen, lymph tissues and cutaneous immune system
3 parts of lymphatic system
- a network of lymphatic vessels
- fluid contained within: lymph
- lymph nodes
process of innate immune response
- infected cell that died will release signal to other cells, stimulates nearby mast cells to degranulate
- capillaries in the area dilute and become more permeable to allow more fluid and immune cells to the area:- acute inflammatory response
4 fundamental symptoms of inflammation
redness, pain, heat, swelling
inflammation definition
tissue injury caused by physical/chemical agent or pathogenic microorganism
heat caused by
capillary widening which causes increased blood flow
redness and swelling is caused by
increased permeability, where fluid is released into tissues
tenderness is caused by
attraction of leukocytes where extravasation occurs (leakage into the surrounding tissue)
pain is caused by
a systemic response, fever and proliferation of leukocytes
processes of inflammation
1- vasodilation, increased permeability of vessels
2- fibrin formation, phagocyte migration, chemical mediators
3- pus formation, abscess occurs if unable to drain (intervention may occur to stop spread of infection)
e.g. of the body’s barriers to infection
epidermis of the skin, mucous membranes, hairs, cilia, saliva, urine, ear wax
eg harmful bacteria
MRSA and c.difficile
exotoxin
secreted by bacteria, causes damage to the host by destroying cells or disrupting normal cellular metabolism
endotoxin
released into the circulation upon disruption of the intact bacteria
enterotoxin
affect the intestines and lead to reduced fluid re-uptake in the large intestine, leads to diarrhoea and fluid imbalance
eg viruses
norovirus, influenza and chickenpox
fungi
organisms that live on hosts that can be alive or dead and reproduce by spores
parasites
live on or in another plant or animal, known as the host
protozoa
single-celled organisms that live in water and damp conditions, eg: malaria
inflammation
body’s protective response against infection and is a complex cellular process involving various types of immune cells, clotting proteins and signalling molecules
acute inflammation
body’s immediate and adaptive response, which causes the area to appear red, warm and swollen. It has a short duration
eg acute inflammation
frostbite, lacerations, bite and burns
chronic inflammation
lasts a long period of time and usually has a negative impact on quality of life. measured by a presence of a protein in the blood known as CRP
eg chronic inflammation
cancer, chronic bronchitis, rheumatoid arthitis
process of chain of infection
mode of transmission, portal of entry, susceptible host, infectious agent, reservoir, portal of exit
bronchitis
inflammation of the lining of the bronchial tubes, this produces poor cilia movement. acute- up to 10 days, chronic-more than 3 months
pneumonia
infection that affects one or both lungs, causes alveoli to fill up with fluid or pus
rheumatoid arthritis
long term autoimmune disorder which primarily affects small joints
gout
crystal induced arthritis, caused by the accumulation of uric acid crystals in joints
sepsis
when your immune system overreacts to an infection and starts to damage your body’s own tissues and organs
sepsis six care bundle
- give o2 to keep stats above 94%
- take blood cultures, to see where the infection is stemming from
- give IV antibiotics
- give a fluid challenge
- measure serum lactate
- measure urine output
( completed within an hour)
