Lecture 1 Flashcards
Factors influencing the extent and severity of an infection:
-Host factors:
1- integrity of non-specific defences 2- competence of the immune system 3- genetic capacity of the responds effectively to as specific organism 4- evidence of previous exposure 5- existence of co-infection
Factors influencing the extent and severity of an infection:
Pathogen factors:
Dose
Virulence of organism
Route of entry
Define the infection
When organism enter the body and increase in number and cause the damage to the host
Is a measure of a microbe’s ability to cause disease—————
Virulence
❌✅
Virulence It is a qualitative measure of pathogenicity and
is measured by the number of organisms
required to cause disease
False -Quantitative
The virulence of microbe determined by virulence factor like?
Capsule
Endotoxins
Exotoxins
Normal resistance to infection divided into?
Non-specific resistance
Specific resistance
Non-specific resistance Refers to?
1-Barriers (mechanical,physical,chemical)
2-Phagocytic cell
(*Neutrophil; first cell will be recruited and it is short live but produce in large number/
*Macrophage)
Monocytes/macrophage express receptor for bacterial lipopolysaccharide mention the name of that receptor?
CD14
CD11b/CD18 , CD11c/CD18 Are?
And recognize what?
- Integrin molecules
- leishmania,Bordetella, Candida and LPS
Mention the Receptor that express on Monocytes/Macrophage?
CD14
CD11b/CD18
CD11c/CD18
Mannose receptor
There are two main sites where pathogens may reside in an infected host ?
Extracellularly in tissue spaces
Intracellularly within host cell
The immune system has different mechanisms of dealing with pathogens mention it?
Extracellularly by Antibodies
Intracellulary by cell-mediated immunity
Mention the typical examples of extracellular pathogenic
bacteria ?
Staphylococcus aureus
Streptococcus pyogenes
Pseudomonas aeruginosa
Escherichia coli
Example of extracellular sites?
Mucosal surfaces Vascular Lymphatic Body cavity fluids Interstitial spaces
✅❌
The biochemical, structural, and genetic factors
(virulence factors) play important roles in bacterial
immunity.
False - pathogenesis
Characteristics of bacteria that are pathogens and
can serve as antigens for detection include:
1-Pili and Fimbriae that facilitate attachment to host cells
2- elaboration of proteins that facilitate entry
3- Bacterial toxins(exotoxins and component of cell membrane (endotoxins,LPO)
4- tissue-degrading enzymes and anti-phagocytic factor
Serological Identification of Extracellular Bacteria divided to and the meaning of each one
1- direct serological testing (detecting Antigens)by using specific Antibodies, serogrouping or serotyping
2- indirect serological testing
(Detecting Antibodies ) mainly IgG,IgM
By using synthetized bacteria antigens
Types of Serological Tests.
- Agglutination
- precipitation
- ELISA
- complement Fixation Test
- immunofluoresence
Syphilis disease caused by?and how it is transmitted ?
- Spirochete Treponema Pallidum
- By sexual contact with other person or maternal-fetal or blood
The spirochetes are able to spread into various
organs and cause _______?
Gummas
Mention the stages of Syphilis?
✍️Primary/ inflammatory lesions ‘chancers’ appear 2 to 8 weeks after infection and last 1 to 5 weeks + serum test for syphilis are positive in 90% of patients after 3 weeks + antibody IgM
✍️Secondary/ occurs 6 to 8 weeks after chancre, characterized
by a generalized rash. It is highly contagious. Serologic tests
are positive, antibodies are mostly IgG.
✍️Latent/ serological tests are still positive.
• Early latent • Late latent
✍️Late or tertiary/ May involve any organ, but main parts are:
– Neurosyphilis
– Cardiovascular syphilis
– Late benign (gumma)
✅❌
Congenital syphilis is transmitted to a fetus after 16th
weeks of gestation.
False 18th
✅❌
Infected mother before 18th weeks can transmitted the disease to fetus
False can’t
