Robbins 9th ed - Chapter 8 - Infectious Disease - Bacteria (1) Flashcards
Name the infectious agent causing anthrax. Describe the key distinguishing features of it.
Bacillus anthracis is a large, spore-forming, gram positive, rod-shaped bacterium.
How is anthrax spread?
Spores in contaminated livestock are spread amongst humans by contact with contaminated meat. This can be by handling, inhaling, or eating the spores.
Name three types of patients that are more common victims of Pseudomonas infection.
Cystic Fibrosis - respiratory Pseudomonas
Burns - burns infected with Pseudomonas –> sepsis
Neutropaenia
What is the key difference in the clinical signs of a patient with Clostridium tetani and a patient with Clostridium botulinum infection?
Clostridium tetani - spastic paralysis
Clostridium botulinum - flaccid paralysis
What is trismus?
Lockjaw (spasm of the jaw muscles).
Describe the key distinguishing features of all Clostridium species.
Gram positive, anaerobic, spore-forming bacilli.
What is the name of the GIT infection caused by Clostridium difficile?
Pseudomembranous colitis.
Name the two clinically significant Neisseria species.
N. meningitidis
N. gonnorhoea
Describe the key distinguishing features of Neisseria species.
Gram negative diplococci.
What is the infectious agent causing Scarlet fever? What is Scarlet fever?
Group A Streptococci (Strep pyogenes). Scarlet fever is an erythematous rash associated with Strep pharyngitis, most commonly in the age range 3-15 years.
Name two diseases that can be caused either by Staph aureus or by Strep pyogenes.
Impetigo (“school sores”).
Toxic Shock Syndrome.
What is clumping factor?
This is a surface feature of Staphylococcal species that allows them to bind fibrinogen and thereby bind to host endothelial cells.
Which gram positive bacteria form clusters like grapes?
Staphylococci (“staphyl” = Greek word for grape). Streptococci form chains.
What does Campylobacter Jejuni infection cause? How is it transmitted?
Campylobacter jejuni is the most common bacterial enteric pathogen in developed countries. It causes traveller’s diarrhoea. It is transmitted by contaminated water, chicken and milk.
Name the virulence factors of campylobacter jejuni.
Motility (with a flagellum), Adherence, Toxin production, Invasion.
Name two extra-intestinal manifestations of campylobacter jejuni infection.
Guillain Barre Syndrome.
Arthritis.
Give three defining features of Shigella.
Non-encapsulated, Non-motile, Facultative Anaerobes.
Describe the pathogenesis of salmonellosis.
Salmonella are gram-negative, flagellated bacilli. Salmonella enteritidis and Salmonella typhimurium invade the intestinal epithelium, and cause gut wall inflammation.
Which of the four different malarial species causes the most severe form of malaria?
Plasmodium falciparum.
Name two cell types in the human body that are infected by malarial parasites.
Hepatocytes and RBCs.
What is the molecular effect of the toxin of Clostridium tetani?
It blocks the release of GABA from neurons.
What is the molecular effect of the toxin of Clostridium botulinum?
It blocks the release of ACh at the neuromuscular junction.
Name the different types of E.Coli
Enteroinvasive E.Coli
Enterohaemorrhagic E.Coli
Enterotoxic E.Coli
Enteroaggregative E.Coli
