Spectrum of Inflammatory Responses to Infection Flashcards
List the categories of infectious agents from smallest to largest
- Prions
- Viruses
- Bacteria
- Fungi
- Protozoa
- Helminths
What is the Creutzfield Jacob Disease (Mad Cow Disease) caused by?
It is caused by an accumulation of prion protein in the brain leading to spongiform changes
What are viruses?
Intracellular organisms which are DNA/RNA surrounded by a protein coat/lipid membrane that can cause transient illness or chronic diseases
What are bacteria?
Prokaryotes that have cell membranes but lack nuclear membranes
What colour are gram +ve and gram -ve bacteria stained respectively?
Blue and Red
What are Fungi?
Eukaryotes that have nuclear and cell membranes. They have thick cell walls. There are 2 forms: rounded yeast forms, and slender hyphae/mould forms. They may cause superficial or deep systemic invasion (in immunocompromised).
What are Protozoa?
Single cell eukaryotes that are found intracellularly or extracellularly. They are a major source of disease in developing countries (contamination of food and water)
What is an example of Protozoa?
Entamoeba Histolytica
What are Helminths?
Parasitic worms. They can exist in Adult form, Immature form, or larva/cyst form.
What is an example of Helminths?
Adult form: Ascaris Lumbricoides
Immature form: Toxocara Canis
Larva/Cyst form: Echinococcus
What are suppurative inflammation mostly caused by
Bacteria - extracellular gram positive cocci and gram negative rods
What is an example of suppurative inflammation that heals without sequelae
Bacterial Pharyngitis
What is an example of suppurative inflammation that is destructive
Klebsiella and Staphylococci (causes lung abscesses that heal with scar formation)
Types of patterns of inflammation
- Suppurative Inflammation
- Mononuclear Inflammation
- Granulomatous Inflammation
- Cytopathic - cytoproliferative reaction
- Tissue Necrosis
- Scarring
What is Suppurative inflammation?
Lots of pus formed by liquefactive necrosis and neutrophils
What is Mononuclear Inflammation?
Predominantly mononuclear infiltrate (lymphocytes, plasma cells, macrophages)
What is Mononuclear Inflammation mostly caused by?
Acute response to viruses, intracellular bacteria and intracellular parasites.
Long-term infections eg. parasites
What are some examples of Mononuclear Inflammation?
Syphillis - plasma cells
Hepatitis B Infection - Lymphocytes
What is Cytopathic - cytoproliferative reaction?
Replication of viruses within cells forming inclusion bodies. There will be cell necrosis or proliferation with minimal inflammatory cells. It may induce multinucleation, cell proliferation or neoplasms.
What is an example of a Cytopathic - cytoproliferative reaction
Herpes
What is tissue necrosis?
When powerful toxins induce rapid and severe necrosis (gangrene)
What is an example of a bacteria that causes rapid tissue necrosis?
Clostridium Perfringens
When does scarring occur?
With long-standing infections, Chronic Hepatitis (Hep B and C), Parasities (eg. Schistosomiasis)
