Who's a fun guy?
You are!
You are!
What is a reasonable initial antifungal of choice in a patient with grumbling abdominal sepsis?
Fluconazole
What kind of virus is SARS-CoV-2?
betacoronavirus
Blood culture shows clumps of gram positive cocci, patient is febrile and hypotensive on flucloxacillin.
What's the organism?
MRSA
A commonly requested test looking for helpful antigens for streptococcus pneumoniae and legionella pneumophila utilises which bodily fluid (aside from sputum)?
Urine
Treatment regimen for a double-vaccinated patient with COVID-19 pneumonitis, requiring oxygen therapy.
Give them the 'BiRD'
- Baricitinib
- Remdesivir
- Dexamethasone
What is the mechanism of action of 'Azoles'?
Azoles prevent the synthesis of ergosterol from lanosterol by inhibiting lanosterol 14 α-demethylase.
Ebola - how many subtypes, and how many outbreaks?
Subtypes: 4
(Zaire, Sudan, Tai forest, Bundibugyo)
Outbreaks: 49 counted on CDC website since 1976
Infection control precautions for Neisseria meningitidis
Contact (Orange card)
AND
Droplet precautions (Green card)
What would you send to the lab if you're concerned about CAPD peritonitis?
Dialysate fluid bag for MC&S and Gram stain
Ubiquitous virus responsible for serious infection in immunocompromised hosts (esp lung transplants)
- Name
- Community prevalence
- treatment / prophylaxis
Cytomegalovirus (CMV)
~50%
Valganciclovir
Toxic effects of Amphotericin, and how are they reduced?
Toxicity reduced by liposomal formulation (but needs higher doses to have same efficacy!!!)
What are the ESKAPE organisms and why are they significant?
Enterococcus faecium
Staphylococcus aureus
Klebsiella pneumoniae
Acinetobacter baumanii
Pseudomonas aeruginosa
Enterobacter spp.
These were named by the IDSA as a group likely to pose the greatest threat to humanity by virtue of their antimicrobial resistance.
Van A, and Van B.
VanA VRE are highly Vancomycin- and teicoplanin-resistant
VanB VRE are teicoplanin-sensitive and moderately vancomycin-resistant.
VanA and VanB can be transferred to other GPC, including staph!
Pleural fluid analysis. What are Light's criteria?
(Bonus points for other features suggestive of infected pleural fluid)
Pleural fluid protein
Pleural fluid LDH
Serum protein
Serum LDH
Classify the effusion as EXUDATIVE if:
- Fluid:Serum protein ratio >0.5 (ie relatively high fluid protein)
- Fluid LDH >200 IU/L
- Fluid LDH:Serum LDH >0.6 (ie relatively high fluid LDH)
BONUS POINTS (20 each)
- Pleural glucose: extremely low suggests TB/pneumonia/malignancy
- Pleural fluid pH <7.2 is basically equivalent to a positive gram stain (normal would be ~7.6)
- Pleural cytology:
--- Lymphocytosis: TB (or malignancy)
--- Neutrophilia: parapneumonic effusion (or PE)
Herpes Simplex Encephalitis
35yo male with HIV on HAART with a 2-week severe headache, fever, malaise, vomiting, confusion. CT brain is normal.
CD4 85 cells/uL
CSF shows 35cm opening pressure, Prot 0.9, Glu 2.1, WBC 48 (Mono 42), 1 red cell, negative gram stain
What is the likely agent, and how would you treat it?
Cryptococcus neoformans
IV Amphotericin PLUS flucytosine
Name 3 multiresistant infections for which there is a critical need for new antibiotics
Acinetobacter baumannii (Carbapenem-resistant)
Pseudomonas aeruginosa (Carbapenem-resistant)
Enterobacteriaceae (ESBL-producing, carbapenem-resistant)
High priority ones are:
- VRE(faecium)
- VISA/VRSA
- H. pylori (clarithromycin-resistant)
- Campylobacter (fluoroquinolone-resistant)
- Salmonellae (fluoroquinolone-resistant)
- Neisseria gonorrhoeae (cephalosporin-resistant, fluoroquinolone-resistant)
Clostridioides difficile
- Treatment options (3 specific)
- Why is handwashing with soap and water necessary over simple alcohol hand-gel?
Treatments
1. Metronidazole (PO/IV)
2. Vancomycin (PO)
3. Faecal microbiota transplant
Soap and water is required to wash away C. diff spores
25yo male, prolonged stay in ICU after a SAH has a CSF specimen taken from his EVD. The cytology shows:
- RBC 2087 x10^6/L
- Polymorphs 189 x10^6/L
- Mononuclears 77 x10^6/L
What does this show?
IF a Gram stain were done, what might it show?
What treatment (if any) would you give?
Ventriculitis
S. aureus, S. epidermidis, S. pyogenes
Removal / replacement of EVD
Vancomycin
Rabies.
- Causative virus
- treatment (2 broad pathways)
Lyssavirus
- IF IMMUNISED:
--- 2 further doses of Rabies vaccine on days 0 and [3-7]
- IF UNIMMUNISED:
--- 5 doses of Rabies vaccine on days 0, 3, 7, 14 and 30
--- IF HIGH RISK EXPOSURE, ADD Rabies immune globulin (HRIG) administered infiltrated around the bite site & any remainder given intramuscularly
58yo female, in ICU for 10 days with necrotising pancreatitis. Today is day 8 of meropenem, vancomycin and caspofungin. In the last 24h she has developed fevers & hypotension, despite line changes.
Blood cultures show a yeast.
Name the likely organism
Name the antimicrobial change should we make
Name the cause for the current regimen's ineffectiveness.
Candida glabrata, or C. krusei, or C. tropicalis, or C. parapsilosis, or Scedesporium spp.
Amphotericin B
Mutation in the gene coding for the fks1 subunit of 1,3-b-D-glucan synthase, conferring a 1000-fold increase in resistance to echinocandins
Name the ESCAPPM group.
Why does this group exist? (and name the mechanism)
They appear sensitive to b-lactams, but resistance develops rapidly due to an induceable chromosomal AmpC cephalosporinase enzyme!
Enterobacter (& E. coli)
Serratia
Citrobacter (& Chromobacterium violaceum)
Acinetobacter (& Aeromonas)
Proteus
Providencia
Morganella
There's also Hafnia alvei, Lysobacter lactamgenus, Ochrobactrum anthropi, Proteus rettgeri, Pseudomonas aeruginosa, Psychrobacter immobilis, Rhodobacter sphaeroides & Yersinia enterocolitica)
56yo male intubated for pneumonia and chest sepsis, fails to improve after 48h of antibiotic therapy, and ETT aspirate shows moderate growth of Klebsiella pneumoniae:
- Amoxicillin R
- Amoxicillin / Clavulanate R
- Cefazolin R
- Cefotaxime R
- Cotrimoxazole R
- Ciprofloxacin R
- Gentamicin R
- Meropenem R
- Tigecycline R
- Ertapenem R
What are the potential enzymes responsible for this resistance pattern?
What are your next management steps?
- Metallo-beta-lactamases (MBL’s – e.g. New Delhi metallo-beta-lactamase)
- OXA beta-lactamase
Next steps:
- ID consult
- need to treat? (yes, obviously)
- Isolation / infection control
- Specific therapy (polymyxins, high-dose mero, cef/avi, aztreonam, etc)
Name 5 novel biomarkers of sepsis
- Pro-adrenomedullin (fragment from same precursor molecule as ADM, which is produced during physiological stress)
- LPS-binding protein (polypeptide involved in LPS signalling. Rises in sepsis. Involved with CD14 signalling)
- sTREM-1 (expressed on surface of myeloid cells, increases in bacterial and fungal sepsis)
- presepsin [sCD14-st] (N-terminal fragment of CD14. Rises <2h of insult)
- HMGB-1 (cytoplasmic and nuclear protein, released by activated monocytes or necrotic tissues)
- CD64 (membrane glycoprotein expressed on the surface of activated neutrophils)
Treatment for Human Metapneumovirus pneumonia in severely immunocompromised host
Ribavirin