Past Papers 2 Flashcards
Electron microscopy images of three viruses
review these now
EM of these viruses
norovirus
rotavirus
adenovirus
Which patient gets each virus?
- elderly patient
- child with diarrhoea 1 month
- child with diarrhoea 2 days
- elderly patient - norovirus
- child with diarrhoea 1 month - adenovirus
- child with diarrhoea 2 days - rotavirus
Norovirus
How long does this patient need to be symptom free until they can be removed from isolation?
48 hours symptom free
i.e not type 5-7 stools and no vomiting
Norovirus
Adenovirus
Rotavirus
Which one is vaccine preventable?
How is vaccine administered?
Rotavirus
Oral vaccine
8 weeks
12 weeks
rotavirus is most common worldwide cause of diarrhoea in children <5 years old
Rotavirus vaccine
What type of vaccine is it?
Which antigens does it target?
Oral
Live attenuated
85% effective against severe rotavirus gastroenteritis in the first two years of life
antigen - viral structural protein - VP4 and 7 most common
What is the structure of rotavirus?
dsRNA
6x viral structural proteins - VP
6x non-structural proteins - NSPs. Only made by cells infected with actual live virus
Non-enveloped
Icosahedralnucelocapsid
What are rotavirus G and P types?
51 P types - based on VP4
36 G types - based on VP7
VP4/VP7 elicit neutralising antibody responses
only few combinations of G and P types predominate and infect humans
They are G1P[8], G2P[4], G3P[8], G4P[8], G9P[8] and G12P[8]
What is common side effect of rotavirus vaccine?
diarrhoea
intussussception
What disease can adenovirus cause?
conjunctivitis
pneumonitis
hepatitis
GI tract - diarrhoea
CMV serology in pregnant woman
IGR with microcephaly
CMV IgG pos
CMV IgM pos
How would you interpret this result?
Suggestive of a recent primary CMV infection, reinfection or reactivation
need further testing to clarify
CMV serology in pregnant woman
IGR with microcephaly
CMV IgG pos
CMV IgM pos
What further tests would you undertake?
CMV IgM/ IgG and avidity on booking blood sample
EBV serology and rheumatoid factor - look for cross-reacting
antibodies
FBC - lymphocytosis
ALT - transaminitis
consider amniocentesis
other infections cause of IUGR
CMV serology in pregnant woman
IGR with microcephaly
What infections would you screen for?
CMV
Rubella
Toxoplasma
Zika
CMV serology in pregnant woman
IGR with microcephaly
If amniocentesis is to be performed, when should this occur?
after 21 weeks gestation - foetal kidneys starting to produce urine with CMV
after 6 weeks of suspected infection date
CMV serology in pregnant woman
IGR with microcephaly
diagnosed with recent primary CMV infection
What is risk of intrauterine infection?
30% in primary infection 1st trimester
70% in primary infection 3rd trimester
3% if reactivation
CMV serology in pregnant woman
IGR with microcephaly
Apart from microcephaly and IUGR, what are 3 other things caused by congenital CMV
IUGR
microcephaly
intracranial calcification
sensorineural hearing loss
retinitis
hepatitis - jaundice
pneumonitis
thrombocytopenia/ anaemia
low birth weight
seizures
blueberry rash
Temporal lobe enhancement on CT - what is the diagnosis?
HSV encephalitis - temporal lobe enhancement is normally pathognomonic
Temporal lobe enhancement on CT
How do you confirm the diagnosis?
Clinically
Lumber puncture - viral PCR, cell count
Temporal lobe enhancement on CT
what is treatment?
IV aciclovir
10mg/kg TDS normal renal function
14 days - repeat LP before stopping
if still positive, then continue another 7 days before repeating LP
HAV/HBV/HCV/HDV/HEV
What is route of transmission
Faecal-oral - HAV/ HEV
Blood borne - HBV/HCV/ HDV
Name two drugs for HBV treatment
Tenofovir
Entecavir
Lamivudine
Adefovir
Interferon
Name two drugs for HCV treatment
NS3/4A protease inhibitor
Grazoprevir
Voxilaprevir
NS5A inhibitor
Elbasavir
Ledipasavir
Velpatasvir
NS5B
Sofosbuvir
Viva
Patient has platelets following Haemopoetic stem cell transplant
Develops hepatitis, and found to be positive for HEV
What action would you take?
Blood is screened for HEV RNA, so this should not happen
Patient
- high risk of acute liver failure/ chronicity
- cannot reduce immunosuppression
- consider chronic at 3 months
- consider starting ribavirin early - risk with blood counts particularly anaemia
- check pre-transplant screening bloods to ensure he did not have infection prior to transplant
Blood product
- identify contaminated sample and test for HEV
- issue may be limit of detection is too low, so low level viraemias are not detected
- issue may be pooled blood screening v individual screening
- screen other patients who are potentially infected
- complete safety alert blood products
Viva
Surgeon presents with maculopapular rash
What diagnoses to consider?
This question is a bit vague
Breakthrough Measles infection
Presumably surgeon has MMR history screened by OH
Need to assess immunity of contacts, and offer HNIG/ vaccine
HIV seroconversion
Measles
Rubella
MPox early rash
Enterovirus
EBV
CMV
GAS
Staph aureus
Surgeon with maculopapular rash
Subsequently found out to be Measles
What PEP is required for contacts?
First check who is susceptible - history of MMR/ immunosuppression
Immunocompetent -
MMR vaccine
Immunosuppressed -
Check Measles IgG - if neg then give HNIG
