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Flashcards in Viral Deck (35)
1

Mechanism of acyclovir?

nucleoside analogue which inhibits viral DNA polymerase

2

Indications for acyclovir?

HSV type 1 and type 2
VSV
occasional EBV

3

Precautions in prescribing acyclovir?

Reduce dose in renal impariment as crystalises in the tubules
Rare - neurologic toxicity

4

Mechanism of gancylcovir?

nucleoside analogue which inhibits viral DNA polymerase

5

Indications for Gancyclovir?

CMV

6

Side effects of gancyclovir?

Resistance can develop through target site mutations (ie. DNA polymerase)
Myelosuppression
Renal impairment

7

Mechanism of action of Ostelmavir?

Neramindase inhibitor
- prevents budding of virus from host cell

8

Indications for Ostelmavir?

Influenza A and B

9

Side effects of Foscarnet?

Renal insufficiency
Electrolyte wasting - low K, MG, phos, Ca

10

Clinical features of CMV infection?

Prolonged fever, night sweats, malaise, anorexia, fatigue, arthralgias
Deranged LFTs, leucopenia, thrombocytopenia, and atypical lymphocytes
Lung involvement: SOB, hypoxia, non productive cough with bilateral interstitial infiltrates that begin in the periphery of lower lobes and spread upwards
GI involvement: oesophageal ulcers, stomach, small intestine or colon, hepatitis (particularly after liver transplant)

11

What complications of CMV occur more frequently in HIV patients?

Meningioencephalitis and retinitis particularly in HIV patients

12

Highest risk time period for CMV after transplant??

1-4 months following transplant

13

Possible treatment options for CMV?

Valgancyclovir
Gancyclovir
Foscarnet
Cidofovir

14

Complications of EBV in the immunocompromised?

EBV lymphoproliferative disorder
Oral hairy leukoplakia in HIV patients

15

Manifestations of HHV-6 in immunocompromised?

Cytopenias
Limbic encephalitis
Hepatitis
Pneumonitis

16

Manifestations of HHV-8 in immunocompromised?

Kaposis sarcoma
Castlemans disease
Primary effusion lymphoma

17

How does ebola virus enter the cell?

glycoprotein 1 and 2 on the surface of virus bind to cell surface markers

18

How does MERs-Cov enter the cell?

Enters via DPP-4 on non ciliated bronchial cells

19

What type of virus is the ebola virus?

Filovirus

20

What type of virus is dengue?

Flavivirus

21

What are the phases of infection with dengue?

inital: fever, retroorbital pain, rash, arthralgia, headache, back pain
defeverescence: occurs around 3-7 days (at risk for getting critical disease - haemorrhagic fever/shock syndrome)
recrudescence: rash, skin desquamation and fever
recovery

22

Complications of Dengue?

Dengue shock syndrome = haemorrhagic dengue + shock
Increased vascular permeability
Marked thrombocytopenia
Torniquet test - petichiae

23

Diagnosis of dengue?

serology - arbovirus Igm/IgG
NS1 antigen can be tested early and is specific
Bloods - plts less than 100 and raised LFts = severe disease

24

Vector of dengue?

Aedes aegyptii

25

Countries that have dengue?

Across equatorial band
- occurs in northern queensland

26

What is the incubation period?

3-10 days
Greater then 14 days - excludes diagnosis

27

Tests for EBV?

Blood film - atypical lymphocytes
Heterophile antibodies (aka Paul Bunnell/Monospot - not sensitive or specific
EBV serology more specific
- VCA IgM/IgG and EBNA
- last for life

28

Causes of infectious mono

EBV most common - 90%
CMV
Toxoplasmosis
HIV

29

What infections do you get with HSV-1?

Oral ulcers
Meningoencephalitis

30

What infections do you get with HSV-2?

Genital ulcers - painful lesions
Meningitis

31

What does antigen shift mean (in context of influenza)

Major genetic reassortment of surface proteins (Haemagglutinin & Neuraminidase)
Cause pandemics as population has not previously been exposed

32

What does antigenic drift mean (in context of influenza)

Point mutations in surface proteins resulting in small change
Cause epidemics/local outbreak as population has seen part of virus before

33

Complications of influenza

Pneumonia - viral and secondary bacterial
Myositis
Rhabdomyelitis
CNS involvement - transverse myelitis, GBS, aseptic meningitis
Myocarditis/pericarditis

34

Groups at high risk for severe influenza

Children 65
Chronic illness
Pregnant
Obesity
Immunocompromised - particularly IgG2
Asthma

35

5 types of illness from Parvovirus B19

Slapped cheek - erythema infectiosum
Polyarthropathy syndrome
Transient aplastic crisis
Fetal infection
Chronic infection in immunosuppressed host