An auto-immune disorder is an immune reaction to one's own calls that creates an environment that involves inflammation and possible tissue damage.
What are the factors of Auto-immune disorders?
Genetic, Cell mutation, reduced suppressor T cell function and viral components
Name the bodys first line of defense?
The skin and mucous membranes
In the 2nd line of defence when inflammation is the hallmark, name the internal defences?
Phagocytes, Fever, NK cells, Anti-mircobial proteins
Explain why it takes longer for the 3rd line of defence to kick in?
The 3rd line of defence is at a cellular level therefore it is not instant
Why do Lymph capillaries have large pores?
One of their roles is to provide a route that enables fluid that has been previously lost from the capillaries into the tissue. It also transports fats digested in the intestine
During Hypersensitivity what are the four patterns?
Type 1 - Immediate hypersensitivity
Type 2 - Antibody mediated
Type 3 - Immune complex mediated
Type 4 - Cell mediated
An example of Type 1 sensitivity is Hay fever why?
The pollen can cause Hayfever in many individuals, it is an antigen to the epithelium layer as it becomes trapped. The immediate body response is by releasing histamine which is chartacterised by vasodilation and drop in BP
What is a Cytotoxic reaction?
The production of antibodies directed towards ones own tissues. It may be a parasitic disease or drug induced.
What type of Hypersensitivity is Rheumatoid Arthritis?
Type 3 - As it is an inflammatory disease, the antigen- antibody remain in the body as they become stuck in synovial joints
Why is Type 4 hypersensitivity referred to as the delayed type?
As it doesn't involve antibodies. The antigen on the cell will stimulate the T cell action. T cells accumulate at the antigen site and release lymphokines which set up the inflammatory response.
In the mechanisms of Auto-immune disease, due to the loss of self tolerance what are the 2 factors?
Inherited and Environmental factors
Briefly describe the T cell Anergy?
T cells only become active when a foreign antigen is detected along with a self antigen, if only one signal is detected then the T cells remain unresponsive
Is mistaken identity a possibility of an environmental factor?
Yes, some bacteria have similar antigens to self antigens therefore antibodies produced against the bacteria may attack the bodys cells.
What are the clinical features of Rheumatoid Arthritis?
Synovial membrane inflammation
Decreased joint movement
Pain, stiffness and swelling in the joints
Name two differences between Crohns disease and Ulcerative Colitis?
Ulcerative Colitis - Starts at the anus and spreads proximally, it is continuous lesions with no healthy bowel tissue between the lesions.
Crohns Disease - Lesions can occur anywhere from the mouth to the anus but there is healthy tissue between the lesions
Is peg feeding an opition for a person with inflammatory bowel disease?
Yes, as it will correct the vitamin deficiency and hypoproteinaemia (decrease in the quanity of protein in the blood) and hypovolaemia (decrease in volume of blood circulating)
What are the common CF of Systemic Lupus Erthematosus?
Vasculitis - inflammation of the blood vessels of the face causing a butterfly rash.
Polyarthritis - Athritis of many joints
Proteinuria - Protein in the urine
Pericarditis - Acute or chronic inflammation of the pericardium.
What is an NSAID?
An NSAID is a Non-steroidal Anti-inflammatory Drug ie Aspirin. It has the ability to block the COX enzyme which produces prostaglandins
What is the difference between 1st & 2nd generation drugs?
The 1st generation are non selective and block both COX's. The 2nd generation is selective and only blocks COX2.
Explain Good Cox?
COX1 - Good. This form of enzyme is associated with producing prostaglandins for homeostatic purposes including regulation of BF and mucas production in the stomach for protection from acid.
Explain Bad COX?
This enzyme is generally associated with protaglandin production at injury site which promotes pain and inflammation.
I am the last part of the Cyclooxygenase pathway, I aid vasoconstriction, Bronchoconstriction and promote platelet function. What am I?
I have the opposite effect as thromboxane but I am still part of the cyclooxygenase pathway. I inhabit inflammatory cell function. What am I?
I am the opposite pathway to Cyclooxygenase. Leukotrienes help induce smooth muscle contraction, constrict pulmonary pathway and increase microvascular permeability.
Why are paracetamol and alcohol a bad mix?
When paracetamol is used correctly it leaves the body via the major pathway therefore becoming a nontoxic metabolite but when mixed with alcohol it creates P450 and becomes a toxic metabolite to the liver causing damage.