sepsis Flashcards
what is infection?
inflammation due to microbe
what is sepsis?
Life-threatening organ dysfunction caused by dysregulated host response to infection
what is septic shock?
Sepsis along with both:
Persistent hypotension (vasopressors needed to maintain MAP at >/= 65)
High lactate (>/= 2)
(with adequate fluids)
most common infection that leads to sepsis?
Lung-lower respmost common
Abdominal
UTI
Skin infection (soft tissue, bone, joint)
Other
Indwelling devices
Best scoring system to identify sepsis?
NEWS>5
What is measured in NEWS?
Respiration rate
Oxygen saturation
Systolic blood pressure
Pulse rate
Level of consciousness
Temperature
timeframe to do sepsis 6?
1 hour
What is sepsis 6?
BUFFALO
BLOOD CULTURES (and Us and Es) + all relevant sites – before antibiotics
URINE OUTPUT (HOURLY!)
FLUID RESUSCITATION
ANTIBIOTICS IV
LACTATE MEASUREMENT
OXYGEN – TO CORRECT HYPOXIA
How many blood cultures in endocarditis to diagnose
3 within an hour before antibiotics
Criteria to assess for likelihood of endocarditis
Dukes criteria
What investigations can be done to diagnose sepsis?
Cultures: blood, urine, stool, wound, tissue cultures
Microscopy: stool, urine, CSF, sputum
Serology – detects antibodies in the blood
Antigen detection
PCR/molecular studies
When the infectious cause is identified sensitivity for antibiotics can be done.
what tests are they
E test- determines the lowest concentration at which the antibiotics inhibit the growth of the organsism.
Vitek machine- gives MICs (minimum inhibitory concentrations for each)
What is MIC?
Mean inhibitory concentration
The concentration of a drug required to kill 99.9% of organisms in 18-24 hours.
Useful to guide antibiotic choice
What inflammatory markers can be measured in the lab?
White cell count
CRP
Procalcitonin (PCT)
Lactate - main one in sepsis
All rise in infection
What drug causes wcc to raise commonly?
Steroids
Lithium
Difference between gram negative and gram positive bacteria?
Gram neg- two layers in cell wall and periplasmic space causing pink staining
Gram-positive- single layer, no space causing purple staining
ways of identifying bacteria
Gram stain
Shape
MALDI-TOF
Anaerobic vs aerobic
What is the MALDI-TOF machine?
Used to identify organisms on a positive culture.
Uses mass spectrometry to identify peaks associated with particular micro-organsims
Common causes of gram negative sepsis?
E. coli
Pseudomonas aeruginosa
H. Influenza
Neisseria meningitidis
Neisseria gonorrhoea
Good antibiotics for gram negative?
Gentamicin (IV only)
Amoxicillin
common side effects of gentamicin
Nephrotoxicity
Ototoxicity
What drug for h. influenza
Amoxicillin
(doxycycline also works)
Does h. influenza grow on blood agar?
No
Chocolate agar only
Causes of atypical pneumonia?
Mycoplasma pneumonia
Chlamydia psittaci
Legionella pneumophilia
Antibiotics that work in atypical pneumonias
Doxicycline – not in legionella
Clarithromycin
Levofloxacin if penicillin allergic
UTI treatment guidelines
In a women:
3 days of nitrofurantoin or trimethoprim
In a man:
7 days of nitrofurantoin or trimethoprim
Complicated:
IV amoxicillin and gentamicin
step down to co-trimoxazole
drug for staph aureus
Flucloxacillin
Vancomycin (if allergic or MRSA)
What route does strep pyogenes cause sepsis through
Skin and soft tissue infection
where does Strep viridans infect
Endocarditis
Doesn’t cause gut infection- this where it lives
Strep antibiotics
Penicillins are still okay
Where do enterococci cause sepsis ?
Infective endocarditits
UTI
Antibiotics for enterococci
Amoxicillin
If resistant: vancomycin
VRE- vacomycin resistant enterococcus use a weirdo antibiotic
Strep haemolysis test
Beta haemolysis
Group A strep
e.g. strep pyogenes
Alpha haemolysis
Strep viridans
Strep pneumonia
Gamma haemolysis
Enterococci
List some gram positive bacilli
Listeria monocytogenes (atypical meningitis in alcoholics, diabetics, over 65 and immunosurpressed)
Bacillus
b. Anthracis (anthrax)
b. Cereus (food poisoning after reheated rice)
Clostridia
c. Difficile (diarrhoea after antibiotics)
c. Tetani (tetanus)
c. Perfringes (soft tissue infection)
Do antibiotics work in abscesses?
No – they require drainage
Mechanism (really simplified) of antibiotic resistance?
Antibiotics are only able to kill certain strains of bacteria
Bacteria with certain traits survive
These bacteria are now able to multiply and colonise
4cs of c. diff
Co amox
Cephalosporins (cef- drugs)
Clindamycin
Ciprofloxacin
How often should you review iv abx?
Daily
Whats source control in sepsis?
Eliminate the source of infection, control ongoing contamination, and restore premorbid anatomy and function
Strategies used to achieve source control include drainage of purulent collections, open or percutaneously, removal of the infected and/or necrotic tissue (debridement), creation of diverting ‘ostomies’, and removing obstruction, among others.
Are people fixed after sepsis goes away?
No
Many physical and mental symptoms persist
Clinical signs of community acquire pneumonia
Cough
Increased sputum
Chest pain
Dyspnoea
Fever
CXR with infilitrates
Needs to be acquired in the community (or first 24 hours in the hospital)
typical bug of CAP?
Strep. pneumonia
Atypical pneumonia bugs
Mycoplasma pneumonia
Legionella pneumonia
Chalmydophilia pneumonia
Chlamydia psittacci
Viruses
Pneumonia type common in the immunosurpressed
Pneumocystis jiroveci - HIV patients+CF
Aspergillus sp. – after organ transplant!
Endemic mycoses
TB
Common in cf
Straph aureus
H. influenza
Strep pneumonia
Main 2
Pseudomonas aeruginosa
Burkholderia cepacia
Diagnosing CAP
Sputum culture
Viral PCR
Additional tests – antigen/biomarkers
Treating CAP
use curb65
CONFUSION
UREA >7
RR >/ 30
BP- SBP < or =90
DBP< or =60
0-2 - Amoxicillin 1g tds IV/PO(5 days)- if penicillin allergic- Doxycycline 200mg PO on day one then 100mg od or IV Clarithromycin
3-5 - Co-amox IV 1.2g tds + Doxy PO 100mg bd- if pen allergic IV Levofloxacin
Neutropenic sepsis?
Sepsis +
Neutrophil count <0.5 or <1 if on chemo in last 21 days
treatment for neutropenic sepsis
piperacillin and tazobactam (add gentamicin if high risk)
When would you suspect malaria?
Up to 1 year post travel to an affected area
Fever
Reduced GCS
Seizures
Respiratory distress
Abnormal bleeding
What bug causes malaria
Plasmodium falciparum
How do you diagnose malaria?
3 x thick and thin films (over time)
Can do a rapid antigen- not that helpful but fast
Whats enteric fever
Typhoid
Paratyphoid
How can typhoid present
Travel to area plus
Maybe asymptomatic
Anaemia
DIC
Meningitis/encephalopathy
Shock
Myocarditis
Bronchitis
Pneumonia
Hepatitis
GI bleed
How does dengue fever present?
Within 14 days of returning from an endemic area
With fever, arthralgia, leukopaenia
Rash- blanches to your hand
how dengue fever managed
Supportive
most common root of meningitis
Ears- otitis media
Nasopharynx
Parameningeal e.g sinusitis, mastoiditis
Haematogenous eg infective endocarditis
types of meningitis
Acute Pyogenic → bacterial
Acute Aseptic → viral, non-infectious
Acute Focal Suppurative → abscess, empyema
Chronic Bacterial → TB
Fungal
what is pyogenic meningitis
The pia-arachnoid layer is congested w/ a thick layer of suppurative exudate (pus) that covers the leptomeninges
Pathogen causes of pyogenic meningitis
Strep. Pneumoniae → extracellular *pneumococcal
Neisseria meningitidis → intracellular *meningococcal
Listeria monocytogenes → gram +ve
H. influenzae
epidemiology of meningitis
Neonates → Listeria, Group B Strep.
Unvaccinated kids → H. influenzae
Age 10-21 → Neisseria meningitidis , Strep. Pneumoniae
Age 21-65 → Strep. Pneumoniae
Age 65+ → Strep. Pneumoniae
Immunocompromised →Listeria
Head Trauma → Staph. Aureus
Cribriform plate fracture → Strep. Pneumoniae
complications of meningitis
SNHL- most common
Limb loss
Blindness
Cerebral palsy
what is aseptic meningitis
meningitis that comes back negative on culture
most common cause of aseptic meningitis
Viral- entero, coxsackie, mumps, HSV, VZV
Diagnostic tools for viral meningitis
stool PCR + culture, throat swab, LP PCR, HIV
treatment for viral meningitis
supportive
Lumbar puncture appearance for bacterial ,viral and fungal
Gross appearance difference
Bacterial- cloudy or frankly plurpent
Viral- Clear/ slightly turbid
Fungal- clear
Lumbar puncture appearance for bacterial ,viral and fungal
Csf pressure
Bacterial- slightly high
Viral- high
Fungal- very high
Lumbar puncture appearance for bacterial ,viral and fungal
Cell present
Bacterial- Neutrophils
Viral- Lymphocytes
Fungal- Lymphocytes
Lumbar puncture appearance for bacterial ,viral and fungal
Protein
Bacterial- very high
Viral- slightly high
Fungal- high
Lumbar puncture appearance for bacterial ,viral and fungal
Glucose
Bacterial- low
Viral- normal
Fungal- low
Lumbar puncture appearance for bacterial ,viral and fungal
Bacteriology
Bacterial- causitive organism
Viral- sterile
Fungal- fungi
when to CT before LP
Papilloedema
GCS <13
Hx of CNS disease
Seizure /focal neuro deficit
Stroke
Immunocompromised
when is LP condraindicated
Raised ICP
Meningitis Treatment
Bacterial- ABX + steroid
steroid- dexamethasone
ABX- 1st line -IV ceftriaxone
pen allergic- IV chloramphenicol+ vancomycin
what comes up on stain for fungal
Fungal treatment for Meningitis
Indian pink stain
IV amphotericin B or flucytosine
Suspect meningitis in GP- what do you give
IM Benzylpenicillin
what is encephalitis+ investigation+ treatment
infection of the brain parenchyma
MRI- bright white in temporal lobes
IV aciclovir
Causes of encephalitis
VZV- chicken pox virus
HSV- older patients
symptoms of encephalitis
Mainly neurological
psychosis
seizure
fever
meningism
speech disturbance
Pathology of guillain barr
B cells secrete Ab that attack pathogens, however the Ag on pathogens matches those on the myelin sheath
diagnostic test for GB
LP- rule out other causes
whats botulism pathology
exotoxin acts on motor neuron terminals to block vesicle docking in presynaptic membrane, irreversibly inhibiting Ach release.
signs of botulism
Rapid onset weakness w/out sensory loss
Ascending paralysis
a person with multiple brain abscesses will get it through which mechanism of infection
Haematogenous spread
what is neutropenic sepsis
Temp >38°C or any symptoms and/or signs of sepsis, in a person with an absolute neutrophil count of 0.5 x 10^9/L or lower.
causes of neutropenic sepsis
chemotherapy is the main reason
immunosuppression, medications e.g. clozapine, methotrexate, sulphasalazine, carbimazole
most common infective pathogen in neutropenic sepsis
gm -ve, pseudomonas, aspergillus
passmed says gram + due to lines in chemo but leactures say otherwise
treatment for neutropenic sepsis
piperacillin+tazobactam
in septic shock add gentamicin
what is a commensal
organism present in body that doesn’t produce inflam response
what is definition of infection
presence of an organism w/ inflam response
what is definition of bacteraemia
presence of bacteria in the blood
what is definition of SIRS
dysregulated host response in response to stimuli (infective or non)
what is definition of severe sepsis
intermediate between sepsis and full septic shock
sepsis antibiotics
amox, metronidazole, gent all IV
if allergy- Vanc, met, gent all IV
sepsis scoring
NEWS and qSOFA
qSOFA- what’s in it
GCS reduction
RR = OR >22
Systolic BP < or = 100
score >2 means concern
antibiotics in sepsis of unknown cause
Amox, met and gent
If P.a- vanc, met and gent
antibiotics in sepsis of meningitis
IV ceftriaxone + dexamethasone
if P.a- IV chloramphenicol + vanc
antibiotics in sepsis of severe CAP
Co-amox + doxy
antibiotics in sepsis of severe HAP
amox + gent
antibiotics in sepsis of C.Diff
oral vanc
antibiotics in sepsis of UTI
amox + gent
if P.A- co-trimoxazole
endocarditis for Native valve indolent
Amoxicillin IV 2g 4 hourly + Gentamicin
confirmed endocarditis sepsis in native valve
flucloxacillin 2g IV 4-6 hrs
endocarditis sepsis which is mrsa in native valve
vanc + gent + rifam (3-5 after starting other antibiotics)
endocarditis sepsis with risk factors for resistant pathogens
vanc + meropenem
prosthetic valve endocarditis
vanc + gent + rifam (3-5 after starting other antibiotics)
