Clinical Microbiology (Week 7) Flashcards
Name three groups of people of highest risk of gastroenteritis
Under 5s, elderly and immunocompromised
Which family does norovirus belong to?
Calciviridae
Which feature of rotavirus gives it the potential for antigenic variation?
It’s 11 strands of RNA
Which strains of Adenovirus cause gastroenteritis?
Adenovirus 40 and 41
Which two types of hepatitis are spread by face-oral route?
Hepatitis A and E
What is the function of selective media?
Suppresses growth of background flora while allowing pathogen growth
Which media type shows lactose fermenting and non-lactose fermenting colonies?
MacConkey’s Agar
Give three examples of gram negative bacilli which cause gastroenteritis
Salmonella Campylobacter E. coli Shigella Vibrio Cholerae
What is the main transmission route of campylobacter?
Animals but also food, milk and water
Which type of E. coli is commonly seen in developing world infants and travellers diarrhoea?
Enterotoxigenic E. coli
What feature of enteropathogenic E. coli allows it to disrupt microvilli?
Bacteria adheres via pili and forms lesion by intimin protein and Tir
Which bacteria produces a toxin which damages epithelium and can cause renal failure?
Shigella (Shiga toxin)
What feature of Vibrio Cholerae allows intestinal mucosa penetration?
Flagella which causes diarrhoea due to protein exotoxin
What is the incubation time of staphylococcus aureus?
30 minutes - 6 hours
What are the 2 types of disease associated with Bacillus Cereus?
Emetic and diarrhoeal disease
Name 2 spore forming gram positive bacilli?
Clostridium Perfringens
Clostridium Botulinum
What is the antibiotic treatment for listeria monocytogenes?
IV Ampicillin and Gentamicin
Which gram negative bacteria can cause outbreaks of septic arthritis in children?
Kingella
What does the acronym DAIR stand for in terms of surgical joint infection treatment?
Debride
Antibiotics
Implant Retained
Briefly describe the condition osteomyelitis
Bone infection characterised by bone death and sequestra (dead bone tissue)
Name three contraindications to lumbar puncture in suspected bacterial meningitis
Brain shift
Raised ICP
Decreased GCS
Clotting disorder
In which circumstance should corticosteroids be given with antibiotics in meningitis?
When the meningitis is definitively known to be pneumococcal
What is the most common antibiotic given in meningitis?
Ceftriaxone
What is the treatment of viral meningitis?
No treatment unless patient is immunocompromised (then give Aciclovir)
Intra-cerebral TB can cause lesions in which 4 cranial nerves?
III, IV, VI and IX
How does neutropenia occur?
Less proliferation of haemopoietic progenitor cells and less marrow reserve
In chronic granulomatous disease, the gene coding which enzyme is defective?
NADPH oxidase
In febrile neutropenic patients, what is thought to cause infection if no site can be identified?
Translocation of bacteria across a compromised mucous membrane
Name two causative viruses of the common cold
Rhinovirus and Coronavirus
Define croup
Inspiratory stridor leading to increased RR, mainly in 6 month olds - 3 year olds
Which two glycoproteins does influenza contain on its surface?
Hemagglutinin and Neurominidase
What are the two types of flu which circulate each year, with one always being more dominant than the other?
H3N2 and H1N1
What is the only type of influenza able to cause a pandemic of flu?
Influenza A
Name 4 features of a baby/infants behaviour to ask a parent about during a history?
Feeding
Crying
Sleeping
Smiling
Name three routes of transmission in HIV
Anal or vaginal sex IV drug use Vertical transmission Health care setting Contaminated blood products
When CD4+ cells fall below what number is a person more likely to have an opportunistic infection?
200
What two features does 4th generation testing for HIV look for?
p24 antigen and HIV antibody
What is Scotland’s viral load target for HIV patients?
<40 viral copies/ml blood
What is the main treatment of HIV?
Highly Active Antiretroviral Therapy (HAART) - triple therapy
Name the components of a sexual health screen and what tests would be carried out
Chlamydia and Gonnorrhoea (NAAT test)
HIV and syphilis (blood test)
What is the treatment of gonorrhoea?
Ceftriaxone
What is the treatment of Chlamydia?
Doxycyline
What type of bacteria is syphilis?
Gram positive spirochete
How long does tertiary syphilis take to develop?
8-15 years
Which types of virus cause anogenital warts?
HPV 6 and 11
Which bacteria causes TB and what kind of bacteria is it?
Mycobacterium tuberculosis, a weakly gram positive
What is the clinical presentation of TB?
Cough +/- haemoptysis and SOB
What is the hallmark of TB?
Granuloma formation (as well as Ghon complexes)
What is the test for latent TB?
Mantoux test
Multi-resistant TB is resistant to which 2 treatments?
Rifampicin and Isoniazid
Extensively drug-resistant TB is resistant to which 4 treatments?
Rifampicin
Isoniazid
Fluroquinilone
One injectable
