[A] 1.15 Spread of the pathological processes in the organism. Septicaemia, sepsis, bacteriaemia Flashcards
Infectious agents are found…
Spreading among animals and within the animal
List the types of infectious agent
- Prion
- Virus
- Bacteria
- Chlamydia, Mycoplasma
- Fungi
- Protozoa
- Helminths
- Ectoparasites
Infection
Entry ⇔ Shed of pathogen
- Can be horizontal/vertical
- Pathogen: Fights defensive mechanisms
List the defensive mechanisms of the body that pathogens must overcome
- Physical barrier (skin)
- Innate immunity
- PRRs (Toll-like receptors)
- PAMPs
- Phagocytes
- NK cells
- Adaptive immunity
- Faster/more effective response when needed
- T- & B-Lymphocytes
Give some brief defensive properties of the skin
- Cornifying squamous epithelium
- Thick keratin
- Low pH (5)
- Fatty acids (Ω3, Ω6)
Transcutaneous infection occurs via…
- Intact skin:
- Dermatophytosis (ringworm)(fungal)
- Malassezia (fungal)
- Through lesions: Papilloma, rabies, tetanus
- Arbo-: Babesiosis, Lyme disease, infectious anaemia, West Nile Virus
Give some brief defensive properties of the GI tract
- Gastric acidity (pH 1-2)
- Viscous mucus
- Digestive enzymes, detergents in the bile
- Defensins
- Normal intestinal flora
- Secreted IgA antibodies (MALT)
Infection to the GI tract
- Per os / Oral(is) infection
- Virus
- Bacteria (Only toxins)
- E. coli
- Fungi
- Parasites
- Larva migrans visceralis
Give the predisposing factors to GI tract infection
- Higher pH in the stomach
- Dysbacteriosis: → antibiotics
- Horse: Linkomycin, tetracycline: Colitis-X, clostridial overgrowth
- ↓ Peristalsis, congestion
- ↓ Digestive enzymes
- ↓ Bile production
- Immunosuppression
Microbiome
Commensalism, symbiotic and pathogen microorganisms
- Analysed by NGS methods (Next-generation sequencing)
- Involved in defence against:
- Autoimmune disease
- Muscle atrophy
- Depression
- Bipolar disorders
Give some brief defensive properties of the respiratory tract
- Nasal cavity - Most inspired particles trapped here
- Mucociliary defence towards the pharynx
- Particles <5μm reach alveoli
- Phagocytes; IgA; neutrophils, B- & T-lymphocytes
- Type II pneumocytes
Aerogen infections
Airborne
- Aerosol: Bacteria; viruses; mycoplasmae
- Travels Kms by the wind; 1–5 μm
- Flying dust: Marek disease; Fungal spores
Oronasal, conjunctival infections
- Bird flu
- Fowl cholera
Urogenital infections
- Venereal
- Semen; erosions on the mucous membranes
- Brucellosis, AIDS, dourine
- Urinary/genital infections: FLUTD, cystitis; pyometra
- Semen; erosions on the mucous membranes
Infection via the umbilicus
Omphalogen (the pathogen)
- E. coli
- Salmonella
Transplacental/intrauterine infections (vertical)
- BVD
- PRRSV (Porcine reproductive and respiratory syndrome virus)
Ovogen infection (vertical)
Salmonella
Infections by the veterinarian
Iatrogenic infection
- PCV2
- EBL
Factors affecting the spread of pathogens and the disease
- Infectivity
- Pathogenicity
- Virulence
- Host specificity
- Invasivity
- Immunological function
- Contagiousness
- Temperature
- Humidity
Give the spread of pathological processes in the organism
Metastasis
The development of secondary malignant growths (lesions)
- At a distance from the primary site
- Cancer; parasites*
The spread of metastasis
Distant metastasis
Give the other forms of metastasis
- Metastasis by contact
- Implantation metastasis
- Pathogens spreading within the:
- Peri-
- Endoneurial lymphatic channels: Rabies, listeriosis, Herpesvirus
Give the outcome of the spread of pathological processes in the organism
Generalisation
Give the different forms of infection
- Bacteriaemia
- Septicaemia - sepsis
- Pyaemi
- Viraemia
Bacteriaemia
- Bacteria in low number
- Only temporary
Septicaemia -sepsis
- Lots of bacteria; prolonged time period
- Bacteria in the organs
- Settlement in the organs
- Pyogenic bacteria (sepsis)
- Rotting bacteria (Sapraemia)
Septicemia - Settlement in the orans
- Bacterial-emboli
- Phagocytotic metastasis
Septicaemia by mycoplasmas
Mycoplasmaemia
Draw the process of SIRS
Systemic inflammatory response syndrome
SIRS: Result
- High TNFα and LPS levels: DIC (Disseminate intravascular coagulopathy)
- Liver damage: Decreasing GNG
- High NO levels: Vasodialtion, ↓BP
- Septic shock
Pathology of septicaemia
- Incomplete rigor mortis
- Dark red blood, incomplete PM coagulation
- Spleen enlargement
- Generalised lymphadenomegaly
- Acute catarrhal (MM) inflammation in the GI tract
- Haemorrhages everywhere
- Cloudy swelling in the parenchymatous organs
