General Review Flashcards
Antigen presenting cells:
macrophages
B-lymphocytes
Dendritic cells
T-cells:
T cytotoxic: killer T-cells
T helper cells:
T helper 1
T helper 2
T cytotoxic cells action.
killer T-cells, recognize MHC 1 = intracellular antigens
T helper cells general actions.
recognize MHC 2 on APCs → activate other cells. APC’s are not infected.
T helper 1 cells action.
activate macrophages, natural killer cells
T helper 2 cells action.
activate B-cells → Ab production
Complement pathways
Classical
Lectin
Alternative pathway
Classical complement pathway is activated by:
Ag-Ab complexes or acute phase proteins
Lectin complement pathway is activated by:
mannose binding protein (MBP) binding to Antigen
Alternative complement pathway is activated by:
foreign pathogens without antibody
Endpoint of complement pathways:
All 3 pathways end the same…
- Enhanced attachment or opsonization (C3b)
- Trigger inflammation/phagocyte chemotaxis (C5a)
- MAC → cell lysis (C5b and others)
Immunoglobulin structure- draw
Hypersensitivity reactions with examples:
Type 1: IgE mediated → eosinophils → anaphylaxis.
Ex: bee sting
Type 2: cytotoxic. Complement mediated or Ab mediated → cell or receptor destruction.
Ex: IMHA, transfusion reaction, myasthenia
Type 3: Ag-Ab complex deposition.
Ex: lupus, lyme GN
Type 4: Delayed: T-cell mediated with prior sensitization → Macrophage activation.
Ex: albumin rxn
List the Endognous pyrogens and their effects:
IL 1
IL 6
TNF-a.
→ cytokine release, macrophage stimulation, release of prostaglandin → hypothalamus → raise set point
Define SIRS & nSIRS
Systemic inflammation.
nSIRS = non-infectious
Define sepsis (OLD)
SIRS due to an infection.
Define sepsis (NEW)
- life-threatening organ dysfunction caused by a dysregulated host response to infection.
- Acute change in SOFA score >/= 2 from baseline (assumed 0 if previously healthy)
- qSOFA: RR > 22, Systolic BP < 100, altered mentation
Define severe sepsis (OLD)
- OLD definition, eliminated with sepsis 3.
- Sepsis + organ dysfunction, hypotension, or impaired perfusion.
- In sepsis 3, all sepsis is “severe”.
Define Septic Shock (OLD)
severe sepsis with hypotension requiring pressors
Define Septic Shock (NEW)
- Subset of sepsis in which underlying circulatory and cellular/metabolic abnormalities are profound enough to substantially increase mortality.
- Requires pressors to maintain systolic BP > 65
- Lactate > 2 despite adequate volume resuscitation
- Hospitality rate > 40%
Define MODS (OLD)
sepsis or SIRS + 2 or more organ dysfunctions
Define MODS (NEW)
- Any acute change in total Sequential Organ Failure Assessment (SOFA) score >/= 2 points as a result of sepsis or nSIRS
SIRS criteria (cat)
3 or more
- T < 100 or > 103.5
- HR < 140 or > 225
- RR > 40
- WBC < 5K or > 19.5K
SIRS criteria (dog)
2 or more
- T < 100.6 or > 102.6
- HR > 120
- RR > 20
- WBC < 6K or > 16K or 3% bands