Opportunistic Infections

Question 1

What is the clinical presentaion of CMV infection in an immunocompetent host?

Answer 1

Common infection (50% seroprevalenc in US)

90% are asymptomatic
10% develop CMV mononucleosis

• Fever, malaise, myalgia/arthralgia, fatigue, headache
• Less common: sore throat, cervical lymphadenopathy, hepatomegaly, splenomegaly

Question 2

What are clinical features of CMV in an immunosuppressed host?

Answer 2

In HIV: CMV occurs when CD4+ <50
with
1. CMV mononucleosis
2. CMV pneumonia
3. CMV retinitits
4. CMV oesophagitis/ gastritis
5. Adrenal insufficiency
6. CMV encephaliis

Question 3

What different families of viruses often cause opportunistic infections in immunocompromised patiens?

Answer 3

1. Herpesviridae (cause latent infections): CMV, EBV, HSV, HHV8, VZV
2. Polyomaviridae: JC virus + BK virus
3. Respiratory viruses Influenza A and B, Parainfluenza 1, 2, 3 and 4, Respiratory
   Syncytial Virus (RSV), Adenovirus, MERS coronavirus
4. Hepatitis viruses A (normally vaccinate prior to immunosuppression), B, C, E
   (increased risk of chronicity)

Question 4

What are the complications of EBV infection in an immunocompromised host?

Answer 4

Can present with many complicaitons of infectious monoucleosis (e.g. splenic rupture) etc.

But also:

• Post-transplant lymphoproliferative disorder: EBV reactivation in patients with severe immunosuppression (e.g., post-transplantation)
  Commonly progresses to B-cell lymphoma: poor prognosis
  Treatment: reduce immunosuppressive therapy

Question 5

Name some fungal infections commonly seen in immunocompromised patients?

Answer 5

Candida
Cryptococci
Aspergillus
Dermatophytes
Mucormycosi