1. Infection - I General Pathology
Basic Principles of Cellular and Organ Pathology
Infection - I
Jaroslava Dušková
Inst. Pathol. ,1st Med. Faculty, Charles Univ. Prague

2. Inflammation - causes AUTOIMMUNE living nonliving prions (?) viral
physical
chemical
living
prions (?)
viral
bacterial
mycotic
parasitic
AUTOIMMUNE

3. Defenses Against Infection – 1.
Surface
barriers: skin, conjunctiva, mucous membranes
mechanical removal: shedding, tears, mucus, ciliary action, coughing, salivation, swallowing, urination, defecation
normal bacterial flora
chemical inhibitors: gastric acid, lactic acid, fatty acids,bile salts..
antimicrobial substances: lysozym, secretory IgA

4. Defenses Against Infection – 2.
Nonspecific resistance factors
fever, interferon, complement, lysozyme, C-reactive protein, lactoferrin, α1- antitrypsin
Inflammation- soluble factors
clotting system –Hageman fc. (XII)
complement system: chemotactic fc, anaphylatoxins
kinin system: bradykinin
Inflammation- phagocytes
circulating: neutrophils, eosinophils, monocytes, macrophages
fixed: alveoli, spleen, liver, bone marow
C-reactive protein reacts with bact surface polysaccharides and activates complement
lactoferrin – bindsand removes iron as a bacterial nutrient
α1- antitrypsin inhibits bacterial enzymes

5. Defenses Against Infection – 3.
Immune response
humoral: B-cells, plasma cells, immunoglobulins
cell-mediated: T-cells, lymphokins
C-reactive protein reacts with bact surface polysaccharides and activates complement
lactoferrin – bindsand removes iron as a bacterial nutrient
α1- antitrypsin inhibits bacterial enzymes

6. Interaction of Organism and Microorganism – Terms
Bacteriemia (transient)
Sepsis/ Septicemia
Pyemia
Toxemia
Viremia

7. Bacteriemia
transient presence of microbes in the bloodstream

8. Sepsis/Septicemia systemic response to infection presenting as
Def.
systemic response to infection presenting as
tachypnoe > 20/min.
tachycardia > 90/min.
temperature > 39 st. C (ev. < 36st.C)
leucocytosis > /1l (ev. < 4000/1l)

9. Syndrome of Systemic Inflammatory Response
Def.
systemic response to an AGENT manifestating as
tachypnoe > 20/min.
tachycardia > 90/min.
temperature > 39 st. C (ev. < 36st.C)
leucocytosis > /1l (ev. < 4000/1l)
AGENT : pancreatitis, injury, burns…..

10. Pyemia
presence of infected thrombemboli bearing virulent microbes in the bloodstream

11. Toxemia
presence of microbial toxin (s) without the microbes themselves in the bloodstream
staphylococcus enterotoxin, botulotoxin

12. Endotoxin lipopolysaccharide component of G- bacteria outer wall
effects: fever, shock, DIC, RDS
effects mediated by IL-1, TNF

13. Exotoxins -1
often enzymes (leukocidins, hemolysins, hyaluronidases, coagulases, fibrinolysins)
others………….

14. Exotoxins -2 diphteria toxin – inhibition of cellular proteosynthesis
botulotoxin – block of the cholinergic transmission
choleratoxin – increase in cAMP, losses of isoosmotic fluid via enterocytes

15. Host & Microorganism Encounter
General
Natural defenses
Inflammation
Immune status
Successful transmission
Site of attack
Number of microorg.
Pathogenicity

16. Host Inflammation Immune status General Natural defenses leucocytes
macrophages -phagocytosis
Immune status
immunity (or lack of it)
active, passive immunisation, contact
lymphocytes
immunoglobulins
complement
General
age, race, nutrition, other diseases (diabetes)
Natural defenses
skin, mucose integrity
mucus, cilliary action, unobstructed flow
protective secretion (lysosym in tears, gastric acid, IgA

17. Microorganism Successful transmission Site of attack
Number of microorg.
Pathogenicity invasiveness
toxin production
multiplication
resistence to host defence mechanisms
ability to cause necrosis
enzyme release

18. INFECTION versus DISEASE
Pathogenicity (virulence)
Incubation Period
Carrier State

19. Agent – Host Interaction
cytocidal
stabilised (steady– state)
transformation – ONCOGENS

20. Inflammation - causes AUTOIMMUNE infectious non infectious prions
physical
chemical
infectious
prions
viral
bacterial
mycotic
parasitic
AUTOIMMUNE

21. Infectious Agents of Humans
prions
viruses (DNA, RNA)
bacteria (incl. chlamydia, mycoplasma, rickettsia – obligatory intracellular parasites)
fungi (yeasts, molds)
parasites (protozoa, helmints, ectoparasites- insects: lice, mites, ticks; spiders)

22. Infectious Agents of Humans Bacteria
simple cells – prokaryotes
both DNA and RNA
cocci, bacilli (AFB!), spirochetes….
Gram positive /negative
extra- and/or intracellular
aerobic/ anaerobic
nemají jádro a erg psynt na ribosomech
většina extracel, mykobakt obojí, chlam, mykopl, rickettsie oblig intracel
AFB acid fast bacilli – stressed due to incidence tb & leprosy

23. Infectious Agents of Humans Fungi
complex cells – eukaryotes
both DNA and RNA
yeasts, molds (hyphae, pseudohyphae…)
PAS, impregnation
extra- or intracellular
mostly opportune pathogens

24. Infectious Agents of Humans Parasites -1
Protozoa
complex cells – eukaryotes
both DNA and RNA
extra- or intracellular
(Amebas, Trichomonas,Trypanosoma, Toxoplasma, Plasmodium, Pneumocystis…)

25. Infectious Agents of Humans Parasites -2
Metazoa (helmints and flukes)
multicellular
both DNA and RNA
flat and round worms
extracellular
(Taenia, Ascaris, Enterobius, Trichuris Echinococcus, Clonorchis, Schistosoma, Wuchereria…)

26. Infectious Agents of Humans Parasites -3
Insecta, Arachnida
multicellular
both DNA and RNA
extracellular
(Sarcoptes scabiei, fleas, ticks, lice……)
svrab = scab
strup = rovněž scab, crust