Cytomegalovirus (CMV) Flashcards
Describe CMV
- A double-stranded DNA virus
- At least 60% of the US population has been exposed
- Member of Herpesviridae family
- Usually causes an asymptomatic infection or mild flulike symptoms in healthy individuals
- Remains latent throughout life and may reactivate
What can CMV cause in HIV patients with CD4 < 50?
- Retinitis – MC manifestation
- GI involvement is not as common, but typically entire GI tract
- Pneumonia, not common with CMV as main cause - typically co-infected with other pathogen
- CNS involvement
CMV in HIV infected patients
-Pneumonia
- Often isolated from patients co-infected with other bacterial, parasitic and fungal pathogens
- May be found in the lungs of 75% of individuals infected by both HIV and Pneumocystis
- In co-infection with Pneumocystis pneumonia, Tx of latter leads to resolution of the pneumonia and hypoxemia
- CMV pneumonia without a co-infecting pathogen is uncommon
CMV in HIV infected patients
-Pneumonia tx
- Tx of asymptomatic persons with evidence of pulmonary CMV is not recommended***
- Tx of CMV when concomitant pathogens are present is not recommended
CMV in HIV infected patients
-GI involvement
- Most likely to occur in patients not receiving antiretroviral therapy
- Involves the entire GI tract
- Upper GI tract involvement-painful dysphagia
- Lower GI tract involvement-diarrhea (colitis)
- Almost always the result of reactivation of latent infection
Dx of GI involvement in CMV
based upon the following triad: clinical symptoms of gastrointestinal disease, visualization of ulcers or erosions, and pathology showing tissue destruction and viral inclusion bodies
CMV in HIV infected patients
-Retinitis definition
- Full-thickness retinal necrosis and edema that is subsequently replaced by thin, atrophic scar tissue.
- Scar tissue is susceptible to tearing, which can lead to subsequent retinal detachment.
Progression of Retinitis in CMV
- Without antiviral treatment or immune reconstitution, the retinal lesions enlarge centrifugally.
- The portions of the retina destroyed by CMV do not regenerate functionally
What is the goal of therapy for CMV retinitis?
To prevent further retinal necrosis and loss of vision*
What is the MC manifestation in HIV patients infected with CMV?
*Retinitis
When does retinitis CMV occur?
When CD4 < 50 cells/ml (up to 40%)
Symptoms of CMV retinitis
- Decreased visual acuity, floaters and loss of visual fields on one side
- Progresses to bilateral involvement that may be accompanied by systemic CMV disease
CMV retinitis - what is seen on ophthalmologic exam?
- Ophthalmologic examination = yellow-white areas with perivascular exudates.
- Ophthalmologic examination = hemorrhage is present and is often referred to as having a “cottage cheese and ketchup” appearance
CMV in HIV infected patients
-CNS involvement
- Uncommon serious complication of AIDS, which can cause paralysis or rapidly fatal encephalitis.
- CMV encephalitis tend to present with delirium
- CMV myelitis or polyradiculopathy may present with lower extremity weakness
Dx of CNS involvement in CMV
Based upon the clinical presentation, and is typically supported by findings on magnetic resonance imaging or computerized tomography and/or documenting the presence of CMV infection in the cerebrospinal fluid through polymerase chain reaction (PCR) assays or antigen testing
