Micro - Antivirals

Question 1

Recent foreign travel to West Africa, present with haemorrhagic fever

Rx?

Answer 1

Ribavirin (also used to treat Hep C & E)

Guanasine analogue, inhibit viral RNA synthesis

Pt has Lassa Fever

ELISA for IgM is ideal

Question 2

Infant has immunodeficiency and needs prophylactic medication

Answer 2

Palivizumab

anti-RSV mAb, used to prevent bronchiolitis and other infection in compromised infants

Active infection of RSV or Parainfluenza can be treated with Ribavirin

Question 3

Post kidney transplant, poor flow and graft rejection. Causative organism?

Answer 3

BK Virus (causing uteric stenosis)

Treat with Cidofivir if very morbid

Cidofivir: Used to treat CMV Retinitis. Also used for Rx resistant HSV. Nephrotoxic so use either Foscarnet or Cidofivir but never both

Is a viral DNA polymerase inhibitor

Question 4

Post BMT, painful and bloody urine

Answer 4

BK Virus (haemorrhagic cystitis)

Treat with Cidofivir if very morbid

Cidofivir: Used to treat CMV Retinitis. Also used for Rx resistant HSV. Nephrotoxic so use either Foscarnet or Cidofivir but never both

Is a viral DNA polymerase inhibitor

Question 5

Adenovirus treated by which antivirus

Answer 5

Cidofivir

Question 6

HSV encephalitis is more likely if Pt is immunosupressed

Answer 6

False

However, more likely to have cutaneous dissemination as well as infection of viscera - hepatitis and oesophagitis

Question 7

Aciclovir relative activity on Herpes

Answer 7

HSV1 > HSV2&raquo_space; VZV

Therefore, give 4x dose for VZV

Question 8

Treating HSV,

What is 1st, 2nd

Answer 8

1st: Aciclovir
2nd: Foscarnet OR Cidofivir (Rx resistant) both nephrotoxic

Question 9

Treating VZV

Which drug and in what circumstances

Answer 9

Aciclovir (same as hsv)

Treat for

neonates chickenpox
adult chickenpox - pneumonitis
shingles aged >50 - post-herpetic neuralgia (nerve pain)
Immunocompromised (all)

Question 10

CMV

What is seen on biopsy

Answer 10

Owl Eye inclusions

Question 11

CMV

Where do they lie latent?

Answer 11

B Cells and dendritic cells. CMV 1st presentation can be similar to glandular fever, then will lie dormant. Will emerge when Pt is immunosuppressed, esp with BMT.

Will present with fever, BM supression and visceral inflammation (pneumonitis, retinitis, hepatitis, GI itits)

Question 12

CMV

Rx?

Answer 12

1. Ganciclovir

Given in immunocompromised retinitis/pneumonitis. Contraindicated in BM suppression (give 2nd line). Hepatonephro toxic

2. Foscarnet
3. Cidofivir

Both nephrotoxic

Question 13

Post-transplant lymphoproliferative disease

Rx?

Answer 13

Rituximab (CD20 mAb)