Microbiology/Infection Flashcards
Staphylococcus Aureus appears as what on a gram stain? What do we usually use to treat it?
Coagulase +ve ,Gram +ve, cocci.
Flucloxacillin.
Enterococcus appears as what on gram stain?
Gram +ve anaerobic cocci
Name some gram +ve rods
ABCDL (anthrax, bacillus, clostridium, diptheria, listeria)
Neisseria meningitidis and Neisseria gonorrhoea are what on gram stain?
Gram -ve diplococci
Name the most common gram -ve rod
E.coli
What antibiotics is pseudomonas often resistant to?
ampicillin, sulphonamides, tetracyclines, chloramphenicol and first- and second-generation cephalosporins.
Haemophilus influenza is what on gram stain?
Gram -ve coccobacilli
What is a +ve ASO titre indicative of?
recent strep infection (e.g., rheumatic fever)
Neutrophil count <0.5 x 10^9 AND fever >38.5 or 2 readings >38 is indicative of what? How should it be managed?
Neutropenic sepsis.
Mx: pip-taz
Parvovirus B19 causes what childhood associated illness? What are the sx?
Slapcheek (erythema infectiosum).
- prodrome: fever, coryza, diarrhoea
- followed by lace-like rash on the trunk and bright red rash on cheeks
How does parvovirus B19 in adults?
Arthralgia and paraesthesia
Until what point is a child with slapped cheek (PB19) infective?
Until rash appears
What are the most common causes of otitis media?
Strep pneumonia, moraxella catarrhalis, haemophilus influenza.
When is the infectious period of measles? How is it transmitted? How does it present?
4-5 days after initial infection - spread by respiratory droplets.
- Koplik spots (white spots) on inside of cheek
- High fever
- Sore eyes (conjunctivitis)
- Coryza
- Rash appears 2-5 days after sx onset
What is a common complication of measles?
Otitis media.
Paromyxovirus causes which childhood associated illness? How does it present? How is it diagnosed? For how long should a patient be isolated?
Mumps.
- unilateral or bilateral parotitis
- fever
- potential sensorineural hearing loss
Measure salivary IgM mumps antibodies.
5 days post parotid sx.
What causes whooping cough? How does it gram stain? How does it present? How is it managed?
Bordetella pertussis - gram -ve coccobacilli
- flu-like sx
- barking cough (associated with vomiting, cyanosis, and syncope)
If sx persist past 21 days prescribe macrolide (clarithromycin).
Having whooping cough increases long-term risk of developing which respiratory pathology?
Bronchiectasis
Bacillus cereus gastroenteritis is associated with which food? How long is the onset?
Vomiting/diarrhoea associated with eating rice, onset is usually within 6 hours of consumption.
What is ‘traveller’s diarrhoea’? How long is the onset?
E.coli gastroenteritis (watery diarrhoea, abdominal cramps).
Onset within 12-48 hours.
What is Threadworm? How is it managed?
Itchy bottom worse at night (when the females lay eggs).
Parasitic infection of large bowel.
Mx: oral mebendazole and hygiene measures.
How does an Entamoeba Histolytica infection present? What is it associated with?
Parasitic amoebozoa infection causing:
- Bloody diarrhoea
- RUQ pain (liver abcess)
- swinging fevers and sweats
Associated with travel to endemic areas (India), MSM, and faecal oral transmission.
Bloody diarrhoea or constipation, abdo pain, rash of rose coloured spots, presenting within 24-48 hour incubation period after returning from Asia is what?
Salmonella typhi
How is Typhoid managed?
Azithromycin or ceftriaxone.
Diarrhoea (bloody or not) and abdo pain presenting within 48-72 hour incubation period is what?
Campylobacter
What is the most common cause of D+V in children?
Rotavirus: vomiting, diarrhoea, decreased oral intake, lethargy, etc.