Antibiotics / Microman (2018) / Microbiology Summary Flashcards
If you’re looking for specific antibiotic treatments then go onto ‘The Holy Grail (Treatments)’ Brainscape subject, and see the deck ‘Infections’. This specific deck will be for general microbiological facts you need to know to understand Antibiotics. It will also cover themes of Tayside Microman 2018.
WANSUM?
Side effects of Gentamycin?
- Renal damage
- Damage to CN VIII (deafness and dizziness)
What family of antibiotics are best known to cause erythema (redness)
Cephalosporins
Purple
Stains well due to thick peptidoglycan wall
Gram positive
Pink
Has a thin peptidoglycan wall
Gram negative
Exotoxin exported from the cell wall
Gram positive
Endotoxin is part of the cell wall
Gram negative
Gram positive chain
Streptococci
Test for Streptococci?
Haemolysis
Alpha haemolysis colour
Partial haemolysis: Green
Beta haemolysis colour
Complete haemolysis: Yellow/ translucent
Gamma haemolysis colour
No haemolysis: Red
Alpha haemolysis organisms
Strep pneumoniae
Strep viridans
Beta haemolysis organisms
Strep (A) pyogenes
Strep B
Gamma haemolysis organisms
Enterococcus faecalis (Strep D)
What diseases does Strep pyogenes most commonly cause?
Strep throat
Rheumatic fever
Acute glomerular nephritis
Scarlet fever
What diseases does Strep viridans most commonly cause?
Endocarditis- post dental treatment
What diseases does Enterococcus faecalis most commonly cause?
It’s a harmless commensal- but can cause intra-abdominal infections if it gets into the peritoneum.
What organisms usually cause bacterial meningitis in newborns
Strep B
What are the two most common organisms that cause bacterial meningitis is adults and children?
Neisseria meningitidis
Strep pneumoniae
Gram positive clusters
Staphlococci
Test for Staphlococci?
Coagulase test
Positive coagulase Staph
Staph Aureus
Negative coagulase Staph
Staff epidermidis
Skin commensals
What does Methicillin-resistant Staph Aureus (MRSA) produce?
Panton valentine leucocidin
This causes necrolytic skin infections
Gram positive bacilli (rods) organisms?
Clostiridium difficile Bacillus cereus Listeria monocytogenes Saccharopolyspora rectivirgula Others
What toxins does C. difficile release?
Enterotoxin A
Cytotoxin B
When stressed- spores that can withstand extreme conditions
How are the investigations for C. difficile?
Stool culture
Bacterial DNA/ toxin
What are the four antibiotics that lead to C. difficile
Ciprofloxacin
Co-amoxiclav
Clindamycin
Cephalosporins (Ceftriaxone)
How does one catch bacillus cereus?
From eating reheated rice
Gram negative cocci organisms?
Neisseria meningitidis
Neisseria gonorrhoeae
Both of these present as diplococci
Gra negative coccobacillus (half cocci, half cocci)
Haemophilus influenzae
Chlamydia Trochomatis
Bordetella pertussis
What does bordetella pertussis most commonly cause?
Pertussis- i.e. “whooping cough” in children
Gram negative bacilli (rods) organisms?
Pseudomonas Escherichia coli Klebsiella Shigella Proteus (vulgaris, mirabilis, penneri) Enterobacter Citrobacter Salmonella
What the shit type of E. coli to get?
E. coli 0157
What does E. coli 0157 produce?
Verotoxin (VTEC)
Gram negative helical shaped organisms?
Campylobacter
Want to know a fun fact about co-amoxiclav?
It treats basically everything apart from Pseudomonas and MRSA
Name some gut commensals
E. coli
Klebsiella
Proteus
Name some gut pathogens
E. coli 0157
Shigella
Salmonella
Organism associated with chest infections and pidgeons/parrots as pets
Chlamydophila psittaci
Organism associated with dry cough and diarrhoea, with a background of holiday abroad + contact with foreign water
Legionella pneumophila
Red jelly sputum
Klebsiella pneumoniae
Rusty sputum
Pneumococcal pneumonia
What’s another name for Strep pneumoniae
Pneumococcal
Chest infection associated with keeping sheep
Coxiella burnetti
What type of gram stain do chlamydiae organisms (Chlamydophila psittaci) have?
They are obligate intracellular parasites but have a similar wall to gram negatives
What type of gram stain does Legionella pneumophila have?
Gram negative
What type of gram stain does Coxiella burnetti have?
Gram negative
What organism is associated with eating beef and BBQs
E. coli
What organism is associated with bakeries / cream cakes?
Staph Aureus (because it enters the cake products from the hands of the workers)
What are the most common organisms that cause early prosthetic valve endocarditis (< 2 months)?
S. epidermidis 28.1%
S. aureus 18.8%
S. viridans 3.1%
What are the most common organisms that cause late prosthetic valve endocarditis (> 2 months)?
S. epidermidis 20.4%
S. aureus 19.4%
S. viridans 15.7%
What are the most common organisms that cause native valve infective endocarditis?
Acute: Staph Aureus
Subacute: Staph Viridans, Enterococcus faecalis
Others: Staph Epidermidis
What are the most common valves affected in infective endocarditis?
Tricuspid 50%
Mitral 20%
Aortic 20%
A common pneumonia from drunk people aspirating?
Klebsiella
Most common causes of meningitis?
Pneumococcus (Strep pneumoniae)
Meningococcus (Neisseria meningitidis)
Most common cause of meningitis >60 years old?
Listeria monocytogenes
Most common causes of encephalitis?
Herpes simplex
Most common causes of epiglottitis?
Haemophilus influenzae, Streptococci
Most common cause of tonsillitis?
Strep pyogenes
Most common cause of sinusitis?
Pneumococcus
Most common causes of acute otitis media?
Pneumococcus, Haemophilus influenzae
Most common causes of Mild/Moderate Community Acquired Pneumonia?
Pneumococcus, Haemophilus influenzae
Most common causes of Severe Community Acquired Pneumonia?
Pneumococcus, Haemophilus influenzae
And possible coliforms and atypicals such as Legionella, Mycoplasma, Chlamydia pneumoniae, Coxiella.
Staph Aureus is common post influenza
Most common causes of COPD exacerbation?
Pneumococcus, Haemophilus influenzae
Most common causes of Hospital Acquired Pneumonia?
Pneumococcus, Haemophilus influenzae and coliforms. Legionella can be hospital acquired.
Most common causes of peritonitis/ biliary tract sepsis?
Polymicrobial coliforms, anaerobes & enterococci
Most common causes of UTIs (male and female)?
Coliforms, Enterococci
Most common causes of pyelonephritis?
Coliforms, Pseudomonas aeruginosa, Enterococci
Most common causes of urosepsis?
Coliforms, Pseudomonas aeruginosa, Enterococci
Most common causes of cellulitis?
Staph aureus, Strep pyogenes
Most common causes of infection in a diabetic foot ulcer?
Staph aureus
Most common causes of septic arthritis?
Staph aureus
Most common causes ofosteomyelitis?
Staph aureus
What organism most commonly causes “rice water stools”
Cholera
What virus causes Chickenpox and Shingles?
Varicella Zoster Virus (VZV)
What organism causes Syphilis?
Treponema pallidum
What virus causes erythema infectiosum “slapped cheek disease”?
Parovirus B19
What organisms cause “Farmers lung”?
Aspergillus Saccharopolyspora rectivirgula (bacteria)
Both often found in hay / mould
Saccharopolyspora rectivirgula produces IgG antibodies> Type IV hypersensitivity
What organism is associated with a stone associated UTI
Proteus sp.
Where is Staph epidermidis most commonly found?
Skin and mucous membranes
Where is Staph aureus most commonly found?
Mainly nose and perineum
What toxins does Strep pyogenes produce?
Pyrogenic exotoxins (SpeB, SpeC)
What two organisms are associated with toxic shock?
Staph aureus
Strep pyogenes
What two organisms are associated with impetigo?
Staph aureus
Strep pyogenes
What organism causes scabies?
Saroptes scabiei
What organisms cause Tinea fungal infections?
- Trichophyton rubrum (>70%)
- Tichophyton menagraphytes (20%)
- Microsporum canis (rare, from cats/dogs)
What conditions warrant a patient getting their own room for precautionary measures?
Strep “A” pyogenes infections
MRSA infections
Scabies
What organisms cause Candida intertrigo (infection)
Candida albicans
Tinea capitis
Scalp
Tinea barbae
Beard
Tinea corporis
Body
Tinea mannum
Hand
Tinea unguium
Nails
Tinea cruris
Groin
Tinea pedis
Foot (athlete’s)
Pediculus humanus capitis
Head lice
Pediculus humanus humanus (corporis)
Body lice (Vagabond’s disease)
Phthirus pubis
Pubic lice / crabs
What viruses cause Herpangina?
Coxackie virus
Echovirus
Causes of erythema multiform?
Bacteria- Mycoplasma pneumoniae from lungs
Virus- Herpes
What viruses cause Hand, Foot and Mouth Disease?
Enteroviruses, Coxackie
What organism causes Lyme disease?
Borrelia burgdoferi
What’s the vector for Lyme disease?
Ticks
What virus causes Orf?
Parapox virus
Most severe parasite that causes Malaria
Plasmodium falciparum
Vector that transfers malarial parasite
Female Anopheles mosquito
Name the organism that produces urease, then breaks down to urea (increasing urinary pH)
It smells foul like burnt chocolate
Proteus sp.
Associated with catheters and instrumentation
Pseudomonas aeruginosa
Most likely organism to infect peritoneal dialysis
Staph epidermidis