Pathology Flashcards
5 Cardinal Signs of Acute Inflammation
- Rubor
- Calor
- Tumor
- Dolor
- Functio Laesa
*1, 2, &3 due to vascular changes (Relaxation of smooth muscle of arterioles and precapillary sphincters
Transudate Characteristics (3)
- Ultrafiltrate of serum
- Specific gravity < 1.012
- Typically transparent
Exudate Characteristics (3)
- Protein Rich (albumin, fibrinogen, immunoglobulin)
- Specific gravity > 1.02
- Can be cloudy in appearance
Jobs of the Lymphatic System (3)
- Remove fluid exudate leukocytes, cell debris, plasma proteins, and fibrin
- Conduit for dendritic cells delivering antigens to lymph nodes
- Carry inflammatory mediators away from site, modulating the inflammatory response
Vasoactive Amines (2)
- Histamine
- Serotonin (5-HT)
Histamine is released following: (3)
- Trauma or exposure to heat or other injurious stimuli
- Binding of IgE to Fc receptors on mast cells in hypersensitivity reactions
- C3a and C5a fragments of complement induce mast cell degranulation
Plasma Proteases (Inflammatory)
- The Kinin System
- The Fibrinolytic System
- Complement
What does the Kinin system do?
- Ultimately produces Bradykinin, a vasoactive peptide that inc vascular perm and cause vasodilation (Intrinsic Pathway)
- Hageman Factor XII binds to neg charged substance or collagen in damaged tissue
- Bradykinin also induces pain and contraction of non-vascular smooth muscle of airways (bronchoconstriction)
What does the Fibrinolytic System do?
- Factor XII initiates a cascade that generates Plasmin
What does Plasmin do? (3)
- Digest fibrin in the clot to form Fibrin split products –> inc vasc. perm.
- Cleaves kininogens to form Bradykinin
- Activates Complement by cleaving C3
Complement System role in Acute Inflammation (4)
- Mediate vasc. resp. via Histamine
- Chemotaxis of Neutrophils
- Opsonization
- MAC: direct damage to target cells
Role of Complement protiens: C3a, C3b, C5a, C5b-C9
Proteins involved in “Rolling” stage of Neutrophil Margination
- P/E Selectin on EC’s
- L Selectin on Neutros
- Sialylated oligosaccharides on cell surfaces (Sialyl-Lewis X)
Proteins involved in Neutrophil “Adhesion”
- Integrins on Neutros
- ICAM-1/VCAM ligands on EC’s (induced by IL-1 and TNF
Chemotactic factors for diapedesis
- Bacterial products
- C5a
- Chemokines
- LTB4
ROS pathway
- O2 to Superoxide via NADPH Oxidase
- O2•- to H2O2 via Superoxide Dismutase (SOD)
- H2O2 to HOCL• (Hypochlorite) via Myeloperoxidase (MPO)
4 Rare diseases caused by Neutrophil dysfunction
- Leukocyte adhesion deficiency type I (LAD-1): defective synth. of CD18-ß subunit of leukocyte Integrins (*Affects Adhesion)
- LAD-2: defect in fucose metabolism –> absence of Sialyl-Lewis X –> no Selectin binding (*Affects Rolling, and some Adhesion)
- Defects in Microbicidal Activity: ROS
- Defects in Phogolysosome formation: Chediak-Higashi syndrome (affects secretory efforts of cytotoxic lymphocytes; Albinism common)
Outcomes of Acute Inflammation (3)
- Complete Resolution
- Progression to Chronic Inflammation
- Scarring or Fibrosis
Patterns of Acute Inflammation (4)
- Serous Inflammation (Transudate, body cavities/blisters)
- Fibrinous Inflammation (Exudate, Adhesions/Scars)
- Suppurative Inflammation (Abscess)
- Ulcer (Granulation tissue formed)
Causes of Chronic Inflammation
- Infectious Agents
- Foreign Bodies
- Products of Metabolism
- Immune Reactions
An adjective describing chronic inflammation that contains activated ofr epithelioid macrophages or giant cells
Granulomatous
*Granulomatous Inflammatory response may not contain granulomas
These are found in the context of granulomatous inflammation; they are compact, centrally organized collections of macrophags and epithelioid cells and often giant cells
Granulomas
Tissue you find under a scab; consists of loose conn. tissue and new blood vessels growing into the fibrin over the wound
Granulation Tissue
2 pathways for Macrophage activation
- Classical (M1): stimulation by LPS, IFN-gamma from lymphocytes, presence of foreign bodies; Macrophages from this pathway are adept at killing via lysosomal enzymes, ROS, and NO
- Alternative (M2): stimulation w/ IL-4 and IL-13; macrophages from this pathway important in healing process, secret growth factors for angiogenesis and fibroplasia
Acute Phase Clinical Tests (2)
- ESR: to detect systemic Inflammatory response
- C-Reactive Protein: to monitor low-grade inflammatory disease
Important contributions that Fever adds to the healing process (4)
- Inc. mobility of leukocytes
- Enhanced Phagocytosis
- Inc. proliferation of T-Cells
- Compromise survival of temp sensitive pathogens
