CA - UTI, Pulmonary Infections, Skin + soft tissue (CKL) Wk 1 Flashcards
Week 1
What are the types of UTI?
- Cystitis
- Pyelonephritis
- serious, needs longer treatment than cystitis - Catheter-associated
- may be polymicrobial
What samples to send for cystitis?
- Mid stream urine culture
- Children: Bag & Suprapubic sample
- Catheter sample (beware positive culture doesn’t always = infection, could be colonization)
What samples to send for pyelonephritis?
- Mid stream culture
- Children: Bag & Suprapubic urine
- Catheter sample
- positive culture doesn’t always = infection, could be colonisation - Blood culture
– if patient is febrile or septic
What samples to send for catheter associated UTI?
- Catheter sample
- urine culture may be polymicrobial: positive
culture doesn’t always = infection!
- dipstix/UFEME results become unreliable
What are the organisms associated with UTI?
- Most common: Ecoli
- Klebsiella pneumonia
- Proteus -> kidney stones
- Enterobacter, Citrobacter, Morganella, Serratia
- Pseudomonas aeruginosa -> previous antibiotic exposure, presence of catheter
- Enterococcus
Whats the management of cystitis & catheter-associated UTI?
If stable and well,
1. PO short course antibiotics
2. Presence of catheter - usually min. 5 days antibiotics
3. Men need longer courses than women
Whats the management of Pyelonephritis & Urosepsis?
- Start IV antibiotics
- PO antibiotic if better after 48 hours
Whats CAP, HAP, VAP and aspiration pneumonia?
CAP Community-acquired pneumonia
HAP Hospital-acquired pneumonia
- occurs 48 hours or more after hospital admission
VAP ventilator-acquired pneumonia
- occurs 48-72 hours after endotracheal intubation
Aspiration pneumonia
- from aspiration of food / mouth flora / gastric content
- in patients with poor gag reflex, difficulty swallowing (stroke) or loss of consciousness
Which pathogens cause CAP?
- Streptococcus pneumoniae
- Haemophilus influenzae
- Mycoplasma pneumoniae
- Chlamydia pneumoniae
- Legionella pneumophila
- Staph aureus (esp. post influenza)
- Klebsiella pneumoniae
- Influenza
Which pathogens cause HAP & VAP?
- Streptococcus pneumoniae
- Haemophilus influenzae
- ‘coliforms’ / Enterobacterales
- Pseudomonas aeruginosa
- Other gram negative bacilli - Acinetobacter
- MRSA (if patient is MRSA positive or high prevalence)
Whats the difference between pathogens causing HAP & VAP?
HAP - hospital full of gram (-) bacteria
VAP - gram (+)
What are the sample types to send to the lab & tests for typical pathogens?
Sputum,
Endotracheal aspirate (ETA)
BAL (bronchio-alveolar lavage)
Gram stain & C&S
What to look out for when testing gram stain?
– if there is high count of epithelial cells -> sample is poorly taken -> unreliable result
What are the sample types to send to the lab & tests for atypical pathogens?
Sample types
1. sputum
2. Endotracheal aspirate (ETA)
- collect lower respiratory tract fluid
3. BAL (bronchio-alveolar lavage)
- collect fluid sample from lungs
TEST:
- PCR
- detect viruses because viral culture is not performed
- for ‘atypical bacteria’ in CAP??
When to send blood culture and what is it tested for?
- For ANY condition if pt is febrile / septic
- test using C&S
What are the signs of cellulitis?
- usually red / hot /tender
- involves subcutaneous tissues, hence more diffuse margin compared to Erysipelas
What are the signs of impetigo?
- commonly seen in children
- reddish sores / perioral
- starts as a vesicle -> ruptures & releases yellowish thick wet crust
What are the pathogens responsible for cellulitis, impetigo, folliculitis, furuncles (bumps) & carbuncles (reddish boils)?
- Staph aureus
- Beta-haemolytic strep (esp Grp A Strep)
What are the features of Type 2 necrotising fasciitis?
- Aggressive
- Easily missed
- Pain out of proportion with skin appearance
- Mortality approx 30%, depends if associated with myositis (causes inflamed muscles, weakness) or toxic shock
What are the pathogens responsible for Type 2 necrotising fasciitis?
- Group A Strep
- Staph aureus
What are the features of gas
gangrene (myonecrosis)? Who are at risk of getting it?
- Uncommon
- Muscle infection
- Develops rapidly, life-threatening
Who are at risk?
1. Clostridial infection – typically after trauma (deep, penetrating injury – knife, gunshot, crush)
2. After bowel surgery
3. Spontaneous! (esp those with colonic cancer)
What are the pathogens responsible for gas gangrene (myonecrosis)?
- Clostridium perfringens (found in soil) -> Necrotic tissue
- Group A Strep -> Spontaneous / haematogenous (originates/spread through blood)
What is the typical pathogen causing Septic arthritis (joint infection), Osteomyelitis (bone infection) & Discitis (spine infection)?
What is the treatment for these infections?
Staph aureus
Treatment
- weeks or months of abx
- might or might not need surgery or joint washout
- is challenging
