Infectious Diseases Flashcards
What is the risk of needlestick transmission for:
Hep B
Hep C
HIV
Hep B - 30-60
Hep C - 3
HIV - 0.3
what lab findings are diagnostic for AIDS
CD4 under 200
viral load over 50000
what are some aids defining illnesses
- karposis sarcoma
- PCP pneumonia
- oesophageal candida
- brain lymphoma
- HIV wasting
- HIV encephalopathy
how do you treat PCP
co-trimoxole
what test do you do with someone with suspected neutropenic sepsis?
Abx choice in unknown source?
Look for source:
- cultures - peripheral and anything in body
- urine
- sputum
- cxr
- LP
antibiotic:
Taz 4.5g IV TDS
Gent 5mg/kg IV
Vanc 1g bd IV
how do you minimise CVC insertion complications in someone with sepsis
- peripheral norad pending
- sterile
- check coags
- best operator
- platelets priot
- US guided
- check placement after
- DVT - US
- contact dermatitis - itchy, oozing, bullae
- insect bite - itchy, confluent, in history
- acute gout - severe pain in joint
- drug reaction - erythematous maculopapualr rash on limgs and extremeties
- superficial thrombophlebtis - tracking erythema, cannula presennt
- status dermatitis - weeping, fluid overload, CCF
what abx cover s.aureus and s.pyogenes
fluclox - 500mg QID
cefalexin - 500mg QID
clinda - 450mg TDS
how does probenecid or clavulanic acid work?
Probenacid - decreases renal excretion of drugs that undergo tubulr secretion eg beta lactams
Clav acid - inhibits beta lactamases to protect drug action
what is the benefit of adding abx to I+D of abscess?
not required unless surrounding cellulitis
small benefit of bactrim particularly in those at risk of MRSA
list two positive and one negative finding
positive
sternotomy wires
circular opacity in valve region consistent with valve
multiple opacties ?septic emboli
neg
no pnemunothorax
no consolidation
specific question in fever in returned traveller
- travel history - where and when, resort/rural, aircon or not, protection eg nets or not
- prophylaxis and immunisation status
- bites or exposures eg sexual, tattoos
- character of fever - onset, cyclical etc
- systems review
how do you diagnose malaria?
- antigen tests - rapid but non specific
- blood films - thick (confirm )and thin (for species)
Why is P.falciparium different to other malarial species?
- high parasite burden
- does not have relapse phase as no hypnozoite phase
- many areas with PF are chloroquine resistant
- complications eg ARDS and mortality are higher
what are the complications of severe p.falciparum infection?
- ARDS
- cerebral malaria
- acute renal failure
- hypoglycaemia
- anaemia
- splenic rupture
for fever in returned traveller list specific examination featurs to certain pathogens
- rash - HIV, dengue, chlamydia
- jaundice - hepatitis
- lymphadenopathy - dengue
- hepatomagely - hepatitis
- petichae - dengue, meningitis
- meningism - meningitis
- splenomegaly - p.falciparium
returned traveller likely diagnosis
why
dengue
high WC
low platelets
anaemia
deranged LFTS
what are the two main treatment options for plasmodium falciparum
Artesunate 2.4mg/kg IV then oral
Quinine 20mg/kg IV then oral
- avoid direct physical contact
- triage patient away from others
- PPE
- dedicated staff for the patient
- enter ED via decontamination area and in isolation room
- notify public health, activate any departmental policies
how do you diagnose the following?
list six causes of fever post transplant and an investigative finding
- CNS infection - high opening pressure
- pulmonary infection - CXR
- surgical site infection - collection on US
- c.diff post abx - stool sample
- acute rejection - ARF/deranged LfTS
- infection of implanted organ - blood tests
diagnosis?
Why?
Common causative agents?
fourniers gangrene
- scrotum oedema
- scrotum erythema
- patches of necrotic skin
Agents
* Strep pyogenes
* staph aureus
* polymicrobial anaerobes and gram negstives
What are the components to managing fourniers/nec fasc
- urgent surgical referral for debridement
- IV abx - vanc 1g, gent, fluclox
- IV fluids for BP over 100
- Glycaemic control
- Analgesia eg fent or morp 2.5mg aliquots
what factors may influence decision to start HIV PEP?
time since exposure
type of intercourse
viral load of patient
?pregnancy
what must be discussed with starting HIV PEP?
- not 100%
- need complete adherence
- follow up testing
- signs of seroconversion
- side effects