Exam 1 Infection & Inflammation

Question 1

In what way is Inflammation a protective response?

Answer 1

Eliminates cause of injury, remove damaged tissue, Generates new tissue

Question 2

What the 2 types of Inflammation and how long do they last?

Answer 2

Acute; minutes to days (vascular permeability and neutrophil proliferation)
Chronic; days to years

Question 3

Causes of acute inflammation

Answer 3

Infection physical injury; surgery; cancer; chemical agents; tissue necrosis; foreign body; immune reaction

Question 4

Stage of Acute Inflammation: Vascular Permeability
What is key behind the permeability ?
Give two types of exudate

Answer 4

Inflammatory mediators (histamine) -> make blood vessels dilate and become more permeable -> fluids, WBC, and platelets travel to the site more easily

Purulent exudate(PUS)= rich in protein from WBCs, microbial debris and cellular debris.

Transudate exudate- contains little protein i.e. blister

Question 5

What are the 5 hallmark signs of inflammation

Answer 5

warm, red and swollen , pain, loss of function;

Question 6

Stage of Acute Inflammation: Cellular chemotaxis

Hint: think of who is sending chemical signals

Answer 6

Movement of cell migration towards the site of injury.
Microbial agents, endothelial cells, WBC- send chemical signals -> attract platelets and other WBCs to the site of injury.
WBCs release different inflammatory mediators (like cytokines, prostaglandins(control blood flow and blood clots), histamines

Cytokines- modulate the inflammatory reaction by amplifying or deactivating the process.
- amplify the inflammatory process - some attract more WBCs - some attempt to stop inflammatory process

Question 7

What is the job Cytokines during inflammation

What organ does it stimulate?

Answer 7

Cytokines- modulate the inflammatory reaction by amplifying or deactivating the process.
- amplify the inflammatory process - some attract more WBCs - some attempt to stop inflammatory process
Cytokines: stimulation of the liver to release substances called acute phase protein.
Acute phase protein are proteins that can ↑ or ↓ the response to inflammation

Question 8

What is FRP and Fibrinogen?

Answer 8

C-reactive protein; key acute phase protein and indicates active inflammation If pt has elevated CRP then this implication of active inflammation in the body

A protein converted to fibrin by the thrombin in response to vascular or tissue injury. This is what you will see in blood clot to prevent bleeding

Question 9

How do histamines work and antihistamines?

Answer 9

FIRST MEDIATOR to be released during acute inflammatory reaction- > binds with H 1 receptors of endothelial cells -> dilatation of arterioles and increase permeability of venules.

the drug would bind to the H1 receptor so histamine cant bind and cause inflammation. Doesnt allow dilation of arterioles

Question 10

What are the types of WBC and their function

Answer 10

Neutrophils (AKA polymorphonuclear leukocytes or PMNs)
Appears within 24-48 hours -> phagocytosis, first responders, Short lifespan; hours-days

Lymphocytes- T cells, B cells, Natural Killer Cells - immune response

Eosinophils- increase number in allergic reaction and parasitic infections Ex. Malaria

Basophils (least amount of) involved in allergic and hypersensitivity reaction

Monocytes- largest in size among the WBC activated after 48 hrs, big brother to neutrophils, phagocytosis

Question 11

Stage of Acute Inflammation: Systemic response (symptoms )

Answer 11

Fever, pain, lymphadenopathy, anorexia, lethargy.

Question 12

What is the most common Systemic response (symptom) of inflammation ?

Answer 12

Fever
Pyrogens are fever-causing substances; microbial organisms, bacterial products and cytokines are all pyrogens.

• A higher body temperature is thought to increase the efficiency of WBCs in phagocytosis.
  Implication: low grade fever can be beneficial in the presence of infection! You dont have to treat in an adult but baby needs treatment ASAP leads to febrile seizure

Question 13

What is Lymphadenopathy or lymphadenitis?

Answer 13

• enlargement of the lymph nodes.
  Lymphocytes mature in the lymph nodes As response to inflammation, there is a proliferation of
  lymphocytes - > lymph nodes become enlarged and tender. Other systemic response:
  anorexia; lethargy
  this is related to cytokines and other inflammatory mediators

Question 14

What is the outcome of Acute Inflammation? If the job is done correctly or incorrectly

Answer 14

Complete resolution
• Injurious agent is eliminated/ activation of chemical mediators caused the area to look good as new

Healing by connective tissue
Development of fibrous scar tissue/ can happen if there is infection

Chronic, persistent inflammation that does not recede ->
inflammation becomes chronic!

Question 15

What causes Chronic Inflammation?

What are the Dominant cells in Chronic Inflammation ?

Answer 15

bacteria ( TB; Mycobacterium spp.; Treponema; syphillus); parasites, fungi;
prolonged exposure to toxic agents like coal dusts; autoimmune diseases.- RA
predominance of monocytes, lymphocytes and macrophages

Question 16

Whats the difference between macrophages and monocytes ?

Answer 16

Macrophages are like monocytes but monocytes are in the blood vessels in the blood moving around from place to place
Macrophages reside in one place

Question 17

What is the name of the area where macrophages are aggregated and are transformed into epithelial-like cells

Answer 17

Granuloma (small area of inflammation) seen in xRays like TB Granuloma
Surround foreign bodies and causes inflammation ex. suture tools in body, asbestos, sutures
1-2 mm lesion - there is a mass of macrophages surrounded by lymphocytes.

Question 18

How are injured tissues repaired?

Answer 18

regeneration of parenchymal cells or by connective tissue repair –> scar formation

Question 19

Explain the 3 phases of wound healing

Answer 19

Inflammation
The process of inflammation is essential in wound healing

Proliferation, granulation tissue formation, and epithelialization
The key cell: fibroblast- connective tissue that synthesizes and secretes collagen; Fills wound space
Final component of this phase: epithelialization; form the surface layers similar to the ones destroyed

Wound contraction and remodeling
Here, there is simultaneous production and lysis of collagen as the scar tissue is remodeled.

Question 20

Explain:

Primary intention (or primary union)

Secondary intention

Tertiary intention

Answer 20

The edges are clearly demarcated, cleanly lacerated. Example- surgical wound •

There is an extensive loss of tissue; regeneration of the same cells are not possible. Scar formation

The wound is missing large amount of tissue and is contaminated;
Needs to be cleaned and left open before closure; wound packing may be necessary; • May require skin graft, Large bed sores

Question 21

What are factors that affect wound healing ?

Answer 21

Nutrition- proteins and minerals
CHON, CHO, Fats, Vitamins A,C, B • Oxygenation

Circulation
Adequate blood supply to bring nutrients and WBC; to remove waste products

Immune Strength - fights infection

Contamination
Can result to healing by tertiary intention; animal bite higher chance of infection especially cats

Obesity
Adipose tissues do not heal efficiently

Age
Decreased inflammatory response, general slowing processes.

Protein and fibroblast

Question 22

Vitamins A,C, B

Answer 22

A- stimulates and supports epithelialization
C- collagen formation
B- enzyme reactors

Question 23

What are some Complications of Wound Healing?

Answer 23

Keloid; There is hypertrophic scar due to excessive accumulation of epithelium and collagen

Contractures- permanent tightening of the muscles, tendons, skin
Wound contraction normally happens without issue.
It can become exaggerated- > deformity burns and joint surfaces Stricture- type of contracture that happens on bodily ducts, canals, or tubes–> GERD

Fistula; Abnormal connection between 2 different organs
Ex: recto-vaginal fistula tube connecting the two leads to lots of UTI’s

Adhesions-a band of scar tissue that joins two internal body surfaces that are not usually connected
Abnormal bands of scar tissues •

Wound rupture- dehiscence; evisceration
• Tension on the wound can cause this
• Dehiscence- previously closed wound open up
• Evisceration- internal organs extrude from the open wound.
Encourage post-op pts to cough to prevent pneumonia, use pillow to cover the area

Question 24

What is infection ?

Answer 24

invasion, colonization and multiplication of pathogens

within the host

Question 25

What causes lyme disease ?

Answer 25

Borrelia burgdorferi bacteria

Question 26

What is colonization?

Answer 26

Microorganism doesnt affect host ex. staph aureus is on the skin when cut it goes in the skin can cause inflammation and infection

Question 27

What are the 5 types of pathogens

Answer 27

Bacteria- can be beneficial or harmful to humans
Ex: Staphylococcus aureus; Treponema pallidum syphillus ; Streptococcus pyrogenes

Viruses-
Microorganisms that depend on host cellular processes for their life cycle and
replication. • Ex: Adenovirus, Influenza virus, Hepatitis A, B, C virus, HIV

Fungi
Mold-like microorganisms that live on human tissue; mycoses- fungal infection; can be superficial or systemic infection • Dermatophytes- tinea infections (T. cruris (ringworm), T. pedis (athlete’s foot); • Candida albicans infection- can happen to immunocompromised individual

Prions- infectious agents capable of causing brain diseases in humans and animals. Lacks nucleic acid can withstand conventional means of sterilization
• Mad cow disease; in human- Creutzfeldt- Jakob Disease (CJD) and the Variant
Creutzfeldt Jakob Disease (VCJD)- human encephalopathy transmitted
through infected beef; • Mad Cow Disease- result from ingestion by humans of prions in infected meat • IP: about 10 years (more or less) but it can lie dormant for ages; • CA- > pass the BBB- > deposited in brain tissue -> degeneration of brain

• Parasite- protozoa, helminths
• Protozoa- Trichomonas vaginalis; Giardia lamblia
• Helminths- Taenia saginata tape worms; Enterobius vermicularis human worms are

Question 28

What is the chain of infection ?

Answer 28

Pathogen 
Reservoir 
portal of exit 
Modes of transmission Direct; cough, Indirect; fomite
portal entry 
Susceptible host