Infectious disease Flashcards
What is sepsis
Significant immune response causing widespread inflammation
In sepsis, what happens to the
Body fluid compartments
platelets
Blood lactate
Oedema due to increased capillary permeability
Thrombocytopaenia due to coag activation
Raised lactate due to hypoperfusion
What constitutes septic shock?
How is it treated
Systolic <90mmHg
AND/OR
Lactate >4mmol/L
Admin of inotropes in HDU (NOT FLUIDS)
Regarding observations in sepsis…
What is the first sign
How do they differ in neutropaenic sepsis?
Raised RR is the first sign
Neutropaenic patients have normal temperature
What are the take 3 give 3 of sepsis?
Take 3
Blood lactate
Blood culture
Urine output
Give 3
Oxygen
IV antibiotics
IV fluids
What lab finding would point towards neutropaenic sepsis?
Neutrophil count <1 x 10^9
What makes up the CURB65 score in pneumonia?
Confusion
Urea >7mmol
Resp rate >=30
Blood pressure <90 sys OR <=60 dia
65+
What are the two most commmon causes of CAP?
- Strep pneumoniae (G-ve, a-haem strep)
- H. Influenzae (G+ve, aerobic bacilli)
What are the 4 most common atypical CAP causes and their associations
Legions of psittaci MCQs
Legionella: cheap holiday, low sodium
Chlamydia psittaci: From birds
Mycoplasma pneumoniae: Target lesions, neuro features
Chlamydia pneumoniae: school aged kids with wheeze
Q-fever (coxiella burnetti): Farmer with flu symptoms
What pathogen is associated with pneumonia in…
Immunocompromised or chornic lung disease
Cystic fibrosis
Cystic fibrosis and bronchiectasis
M. Catarrhalis
S. Aureus
P. aeringuosa
What pneumonia bug do the following get
Immunocompromised patients
Alcoholics
Pneumocystis jiroveci
Klebsiella
How do you treat
Mild-mod CAP
Severe CAP
Non severe HAP
Severe HAP
Pneumocystic pneumoniae
5 days Amox (dox + macrolide)
PO Co-amox + dox (levofloxacin)
PO Amoxicillin (Doxycycline)
IV amox + gent (co-trimox + gent)
Co-trimoxazole, can be given prophylactically
How can you differentiate between lower and upper urinary tract infections?
Lower: Dysuria, incotinence; confusion in older patients
Upper: Fever, loin pain, haematuria
What testing should be performed in a suspected UTI?
Dipstick for nitrites and leukocytes
MSSU for culture
What is the most common cause of UTI?
E. Coli (G-ve, anerovic rod)
What is the management of the following UTIs
Lower UTI in
Males
Non-pregnant
Pregnant
Upper UTI
Males: Nitro/trimethoprim 7 days
Non-pregnant: Nitro/trimethoprim 3 days
Pregnant
asymp: nitro/amox/cefelexin 7 days
symp: 1. Nitro 2. Amox/cefaxelin 7 days
Upper: Co-amoxiclav/ Co-trimoxazole 10–14 days
When are the following antibiotics avoided in pregnancy for UTI and why?
Nitrofurantoin
Trimethoprim
3rd trimester due to haemolytic anaemia in newborns
First trimester to tue neural tube defects
What are the 3 most common causes of cellulitis?
What is the other cause to be aware of?
S. aureus
group A strep
Group C strep
MRSA
What antibioitic is given for cellulitis?
Flucloxicillin
What is the most common cause of tonsilitis, otitis media and rhinosinusitis?
VIRAL
What are the two most common bacterial causes of tonsilitis, otitis media, sinusitis?
Strep pyogenes
Strep Pneumoniae
When is antibiotics given for tonsilitis?
What do you give?
CENTOR >=3 OR FeverPAIN >=4
Phenoxymethylpenicillin (Pen V) for 10 days (clarithromycin otherwise)
What indicates otitis media and when would you consider antibiotics?
Painful ear with bulging tympanic membrane +/- discharge if perforation
If >3 days, under 2yrs, discharge or systemic infection
What is the first line treatment for otitis media?
Amoxicillin PO 5 days (clarithromycin)
How does duration of symptoms dictate sinusitis antibiotics?
<10 days: no therapy
>10 days: trial 2 weeks high dose nasal spray
+ if >10 days and likely bacterial cause: Pen V (clarithromycin)
What are the two broad bacterial groups causing intra-abdominal infection
Coliforms (E. Coli, Klebsiella, enterobacter)
Anaerobes (bacterioides, clostridium)
What regime is used in Tayside for intra-abdominal infection?
Amoxicillin (+ves) + Metronidazole (anarobes) + Gentamicin (-ves)
Replace amox with vanc if allergic
In Tayside, what is used for the following SBP infections
Mild
Severe
Co-trimoxazole PO
Piperacillin/tazobactam then Co-trimoxazole
What should you do for a red, hot, swollen joint with reduced mobility?
Aspirate to for microbiology to exclude septic arthritis
What is the most common cause of septic arthritis?
S. aureus
What should you suspect in younger patients with septic arthritis?
Gonococcal infection if sexually active
What is the treatment of septic arthritis
Empirical until sensitivities back
Usually flucloxicillin
What are the causes of viral gastroenteritis?
Rotavirus
Norovirus
Adenovirus
Name the pathogen that fits the gastroenteritis history
Pork, 4-7 days incubation, children with lympahdenopathy
Uncooked rice, IVDUs, 8hr incubation; vomiting 5hrs, diarrhoea 8hrs, resolution 24hrs
Unwashed salad or water, antibiotic use, + blood
Water, pools and food, 1-2 days incubation
Raw eggs and poultry; 12hr-3d incubation, watery+/- mucus, blood
Travel, uncooked poultry, water; 2-5 days incubation, + blood
Yersinia
Bacillus Cereus
E. Coli
Shigella
Salmonella
Campylobacter jejuni
What is the general approach for gastroenteritis?
Send stool for MCS
Fluid challenge +/- oral fluids
Generally avoid antidiarrhoeals and antiemetics
Isolate for 48 hours post-symptoms
What are the common causes of bacterial meningitis in
Adults and children
Neonates
N. meningitidis, S. pneumoniae
GBS
What can help clinically identify meningitis in
Adults and children
Newborns and infants
Straighten knee with flexed hip (Kernig) or put chin to chest (Brudzinkis sign), will cause resistance or pain
Perform LP…
<1 month + fever
1m-1yr: Fever + unwell
What is the typical treatment for bacterial meningitis if
In community
Hospital
Community
IM benpen (<1yr: 300mg, <9yr: 600mg, >=10yr: 1200mg)
Hospital
<3 months: Cefotaxime + amoxicllin (cover listeria)
>3 months: Cetriaxone
+ Vanc if travel, long term therapy
+ Dexamethasone if >3 months 4 x 4 daily
Who else gests treated following a suspected meningitis case and what is given?
Close contacts in past 7 days
Single dose ciprofloxacin
What are the common causes of viral meningitis?
HSV
Enterovirus
VZV
What is the most worrying form of malaria?
Plasmodium falciparum
Outline malarial transmission
Infected blood –> Anopholes mosquito –> sporozites in gut –> infection to human –> travel to liver to infect RBCs
Why do malaria patient have pallor, jaundice, hepatosplenomegaly and 48hr fevers
Travel to liver, infect RBCs, cause them to rupture then further infect
How do you diagnose malaria?
3 samples over 3 days in EDTA for malaria blood film
How do you treat the following malaria forms
Uncomplicated falciparum
Severe falciparum
Non falciparum
Uncomplicated: ACT combos -will be ‘arte’ plus another drug, Quinine + doxy/clinda
Severe: IV artesunate if >2% count, exchange transfusion if >10%
Non-falciparum: Chloroquine
