pathology of bacterial infection st1 n.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
PATHOLOGY OF BACTERIAL INFECTION {ST1} PowerPoint Presentation
Download Presentation
PATHOLOGY OF BACTERIAL INFECTION {ST1}

Loading in 2 Seconds...

play fullscreen
1 / 11

PATHOLOGY OF BACTERIAL INFECTION {ST1} - PowerPoint PPT Presentation


  • 130 Views
  • Uploaded on

PATHOLOGY OF BACTERIAL INFECTION {ST1}. BY RANJEET RAMAN. Host response factors that influence infection:

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'PATHOLOGY OF BACTERIAL INFECTION {ST1}' - ken


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
slide2

Host response factors that influence infection:

​intrinsic defenses (skin barriers, cilia, lysozyme in mucosal secretions) ​innate immunity (complement, PMN efflux and adhesion, toll-like receptors) ​adaptive immunity (B and T cells, resident dendritic cells and monocytes to ​present antigens, cytokine release)

slide3

Bacterial factors that influence infections:

​route of entry

​size of inoculum

​bacterial products that damage host tissue and alter host physiology ​evolutionary adaptation to host

slide4

Histopathology of bacteria

Extracellular bacteria cause acute inflammations with lots of PMNs and edema. Depending ​on species there may be necrosis, with pus or abscess. Over time, inflammation ​becomes chronic. Extracellular bacteria are clinically much more common.

​examples include Strep pneumoniae, Staph aureus, H. pylori, Vibrio vulnificus

slide5

Intracellular bacteria cause chronic inflammations, sometimes with acute or ​granulomatous inflammation as well. Lots of macrophages, lymphocytes, ​sometimes epithelioid macrophages. May be caseous necrosis or small abcesses.

​examples include Mycobacterium tuberculosis, Salmonella typhi, Rickettsia rickettsii

slide6

Host tissue responses to bacterial infection 1. Exudative inflammation. Vascular permeability brings in PMNs. Lots of pus. ​Typically caused by localized extracellular pyogenic bacteria. Pathology results ​from inflammatory responses (consolidation in lungs, edema).

slide7

2. Necrotizing inflammation. The exudative response plus necrosis (“suppuration”). ​Pathology results directly from bacterial toxins.

3. Granulomatous inflammation. Characterized by accumulation of activated epithelioid ​macrophages. Caused by bacteria that resist PMN attack, usually obligate ​intracellular bacteria. Granulomas form when macrophages secrete cytokines like ​IL1 and GM-CSF.

slide8

4. Interstitial inflammation. A non-specific chronic inflammation. Even when arising ​acutely, infiltrates with lymphocytes, macrophages, plasma cells. This suggests a ​viral or spirochete bacterial infection, such as Treponema pallidum (syphilis). When ​seen with inflammation/necrosis of the vascular wall, suggests Rickettsia rickettsii.

slide9

5. Cytopathic or host proliferative changes. Typically from viral infections.

6. The Null reaction. Absence of inflam, necrotizing, or cytopathic signs. Rarely occurs in ​bacterial infections. May be seen in hosts with physiological, inflammatory, or ​immune defects.

slide10

Host tissue responses to bacterial infection 1. Exudative inflammation. Vascular permeability brings in PMNs. Lots of pus. ​Typically caused by localized extracellular pyogenic bacteria. Pathology results ​from inflammatory responses (consolidation in lungs, edema).

slide11

2. Necrotizing inflammation. The exudative response plus necrosis (“suppuration”). ​Pathology results directly from bacterial toxins.