Opportunistic viral infections

Question 1

Retinitis in AIDS

Pneumonitis in BMT

Answer 1

CMV

Question 2

Post-transplant lymphoproliferative disease

Answer 2

EBV

Question 3

Common characteristics of Herpes viruses

Answer 3

DNA viruses

Primary infection -> Latent -> Reactivation

Question 4

Latent in sensory nerve ganglia

Answer 4

HSV, VSV

Question 5

1 oral ulcers, 2 genital ulcers
1 trigeminal nerve, 2 sacral nerve latency
Small painful fluid filled blisters
Herpetic Whitlow (finger)
Herpes gladiatorum (wrestlers - trunk, extremities, head)
Keratoconjunctivitis (tearing, blurriness, pain)
Encephalitis / meningitis (1 brain)
Immunocompromised - oesophagus, liver, lung
Tx: Acyclovir

Answer 5

HSV

Question 6

• Flat red itchy spots (macules) -> elevated (papules) -> fluid filled vesicles crust over
• Tzanck cells (big multi-nucleated giant cells) if looked at fluid
• Tx: Self-limiting if immunocompetent, if immunocompromised - IV acyclovir + VZV IVIG if significant exposure

Answer 6

VZV

Question 7

Latent in B lymphocytes
90% of population infected by age 80 - very easily spread!
Asymptomatic if immunocompetent - occasionally CMV mononucleosis like EBV
Retinitis (Pizza sign) + pneumonitis in immunocompromised
Owl’s eye inclusions
Tx: Gancyclovir

Answer 7

CMV

Question 8

Latent in B cells, T cells + epithelial cells
Spread by saliva (kissing disease)
Infectious mononucleosis (glandular fever)
Heterophile antibody test (monospot / Paul-Bunnell) classically used for diagnosis -> but negative in 1st week / after infection cleared so anti-VCA / anti-EBNA detection better
EBV-associated cancers (Burkitt’s, nasopharyngeal carcinoma, post-transplant lymphoproliferative disease)

Answer 8

EBV

Question 9

Fever then transient rash as fever is subsiding

Most common cause of febrile seizures

Answer 9

HHV6 - Roseola infantum / Sixth disease

Question 10

Purple lesions + spindle cells

Answer 10

Kaposi’s sarcoma

Question 11

Kaposi’s sarcoma
Primary effusion lymphoma
Castleman’s disease

Answer 11

HHV8

Question 12

Non-cancerous growth in lymph nodes

Giant lymph node hyperplasia

Answer 12

Castleman’s disease

Question 13

Paediatric post-BMT

Answer 13

Adenovirus

Question 14

Progressive multifocal leukoencephalopathy

Answer 14

John Cunningham Virus (JCV)

Question 15

Chronic anaemia in immunocompromised

Answer 15

Parvovirus

Question 16

Polyoma virus
Haemorrhagic cystitis (BMT)
Nephritis (Renal transplant)

Answer 16

BK virus

Question 17

Tx Herpes infections

Answer 17

Acyclovir (VZV, HSV1 + 2), Gancyclovir (pt. CMV but can be used for HHV6, HHV8)
2nd line: Foscarnet, cidofovir

Question 18

Why does acyclovir not work in CMV?

Answer 18

CMV has a different type of thymidine kinase that phosphorylates gancyclovir but not acyclovir