MMB (022) Red Hot Joint Flashcards
Cardinal signs of acute inflammation ?
Types of Reactions of acute inflammation ?
-Vascular
-Cellular
Order of Vascular changes in acute inflammation ? B
- Transient, insignificant, vasoconstriction
- Arteriolar vasodilatation»_space; increased blood flow with engorged capillaries.
3.Increased vessel permeability»_space;SWELLING
Three characteristic microscopic features of this blood vessel ?
• A dilated BV
• Engorged with RBCs
• Leukocytes at the periphery of the blood stream
What are the immediate causes of increased vascular permeability?
- chemical mediators (histamine, bradykinin, NO, C5a, L PAF) [transient]
- severe direct vessel injury [sustained]
What are the delayed causes of increased vascular permeability?
Endothelial cell injury (e.g. bacterial endotoxins) [prolonged]
Cellular events of inflammation mainly revolve around recruitment of… ?
Leukocytes
What is the most important function of inflammatory response?
• Deliver leukocytes to the site of injury
• Activate leukocytes
What is the function of leukocytes?
• Ingest the microbe
• Kill it
• Eliminate necrotic tissues and foreign substances
the type of leukocyte emigrating to the site of infection depends on the…… and the….
duration of inflammation ,, type of stimulus
…cells :
when recruited to inflammation site ; are short lived and die by apoptosis
PNLs
…cells :
when recruited to inflammation site ; survive longer than PNLs
monocytes
…cells :
Are recruited to inflammation sites in the 1st 6-24 hours
PNLs
…cells :
Are recruited to inflammation sites in 24-48 hours
monocytes
General infections lead to ….. recruitment
continuous PNLs
Viral infections lead to ….. recruitment
lymphocytes
Hypersensitivity reactions lead to ….. recruitment
eosinophils
When are Leukocytes activated ?
Once they reach site of infection
How are Leukocytes activated ?
Through microbes, necrotic products & mediators
Some mediators of acute inflammation ?
• Vasoactive amines
• Complement components
• Eicosanoids
• Clotting cascade
• Kinin cascade
Beneficial effects of acute inflammation ?
-dilution of toxins
-entry of antibodies and drugs
-cell nutrition and oxygenation
-start of immune response
Harmful effects of acute inflammation ?
-Damage to normal tissues (enzymatic digestion, abscess cavities, vascular damage)
-Swelling in critical sites (epiglottis, brain)
- Immune hypersensitivity reactions (causing tissue damage and even life-threatening consequences, e.g. asthma
What are the common causes of a red hot joint?
- Infection
- Crystal deposition
- Flare in activity of chronic arthritis
- Trauma
Routes of infection ; of Septic arthritis ?
- Hematogenous (blood borne infection)
-Direct extension from a soft-tissue abscess or osteomyelitis
Risk factors ; of Septic arthritis ?
- Existing joint problems (e.g. osteoarthritis, gout, rheumatoid arthritis, an artificial joint, previous joint surgery)
-Joint trauma
-Weak immune system ( diabetes, kidney and liver diseases, drugs suppressing immunity)
-Increased skin fragility and poor healing of wounds
How to diagnose a case of septic arthritis?
-Examination of synovial fluid :
• White cell count, which is usually very high.
• Culture for bacteria or other organisms
- X-rays:
done only to look for damage or to rule out other causes - Blood tests :
to monitor inflammation
What’s the abnormality in this Synovial fluid smear ?
What is GOUT ?
-Gout is a disorder of purine metabolism. Its final metabolite, uric acid, crystallizes in the form of monosodium urate, precipitating in joints, tendons, and tissues
-The crystals then trigger a local immune mediated inflammatory reaction
The final metabolite of purine is ….
uric acid
uric acid crystallizes in the form of…. In tissue
monosodium urate