Gram Negative Bacteria Flashcards
Does salmonella ferment lactose?
NO
What type of organisms is pseudomonas?
Strict aerobic bacilli water and soil organisms
Contaminates medical equipment
Hospital acquired cause of sepsis: pneumonia, UTI Respiratory infection in cystic fibrosis
What causes tuberculosis?
Mycobacterium tuberculosis
What is the test for syphilis?
Serology, nucleic amplification tests
What type of organism is E.Coli?
Coliform - large gram negative aerobic bacilli
What are the strains of chlamydia that cause respiratory infection?
Chlamydophila pneumoniae
Chlamydophila psittaci - contact with birds
Name a microaerophilic spiral bacilli
Helicobacter pylori - natural habitat is human stomach - damages mucosa and causes ulcers
What causes leprosy?
Mycobacterium leprae
What is the ZN stain used for?
Mycobacterium species
What family do Coliforms belong in?
Enterobacteriaceae Inhabitants of the gut
What strain of chlamydia is responsible for the Ophthalmic and genital tract infection?
Chlamydia trachomatis - trachoma (tropical eye infections) Can lead to pelvic inflammatory disease and infertility
What does salmonella cause?
Enterocollitis, with or without bloody diarrhoea
What does typhoid cause?
Fever and constipation
What are the sub divisions of gram negative aerobic bacilli?
Large (coliforms)
Small
What type of organism is salmonella?
Gut pathogen Coliform
What type of bacteria is chlamydia?
Obligate intracellular bacteria
Give an example of a spirochaetes
Treponem pallidum - syphilis
Borrelia burgdorferi - lymes disease
What does Moraxella Catarrhalis cause?
Respiratory tract infections
What are the virulence mechanisms of Escherichia coli?
pili, capsule, endotoxin and exotoxins produced
What does microaerophilic mean?
Requires little free oxygen
What are the important anaerobes? (BACILLI)
Bacteriodes Fragilis - normal colonic flora
Causes intra-abdominal abscess
Define congenital
Present from birth
What are the gram negative bacilli other than coliforms?
Bordetella pertusis - whooping cough
Haemophilus infuenzae - cocco bacilli (mixed appearance) respiratory tract infection - capsulate form formerly an important cause of meningitis
What is meant by miscellaneous bacteria
Can’t be stained with gram stains
Can’t be cultured under standard methods Mycobacterium Spirochaetes Chlamydia
What is the test for gram negative bacilli?
Lactose fermentation
Name a curved microaerophilic gram negative bacilli
Campylobacter - commonest cause of bacterial diarrhoea in the UK
How is diagnosis of chlamydia achieved?
Nucleic acids amplification tests
What are the stages of lymes disease?
- Skin rash
- Systemic illness - cardiac or neurological and musculoskeletal symptoms
- Chronic disease - skin, nervous system or joint abnormalities
What are the forms of Neisseria spp that are of clinical significance?
Neisseria Meningitidis - meningitis and septicaemia
Neisseria ghonorrhoeae - urethritis in men - pelvic inflammatory disease
What are the stages of syphilis?
Primary - Non-painful skin legions
Secondary - Systemic illness and rash
Latent - symptomatic episodes may occur
Tertiary - central nervous system Congenital - stillbirth, neonatal death or disease
What type of bacteria are Neisseria spp and Moraxella catarrhalis?
Aerobic gram negative cocci
Does E Coli ferment lactose?
Yes
What is used to detect spirochaetes?
Dark ground microscopy or immunofluorescence - Often diagnosed by serology
What is the cause of typhoid fever?
Salmonella typhi
What other commensals of the gut exist? (apart from E.Coli)
Klebsiella - UTI and pneumonia
Proteus spp - UTI
Name an oral anaerobe
Prevotella - cause of dental abscess (pus that forms in the teeth and gums), aspiration pneumonia, human and animal bite infections.
Name another gut pathogen that isn’t salmonella or E.Coli
Shigella - diarrhoea, dysentery
What is the infection usually associated with Ecoli?
Urinary tract infection
Enterotoxogenic E.Coli - commonest cause of travellers diarrhoea
Enterohaemorrhagic E.coli - Bloody diarrhoea Haemolytic uraemic syndrome
