From the Guidelines
Disseminated varicella-zoster virus (VZV) infection is indeed considered an AIDS-defining illness in HIV-positive individuals, as it indicates severe immunosuppression and increased morbidity and mortality risk. According to the CDC classification system, when VZV infection spreads beyond a single dermatome and affects multiple organ systems in someone with HIV, it meets the criteria for an AIDS diagnosis, typically occurring when CD4 counts fall below 200 cells/mm³ 1. Disseminated VZV presents with widespread vesicular lesions affecting multiple dermatomes and potentially involving organs like the lungs, liver, and central nervous system.
Key Considerations
- The risk of developing severe chickenpox or herpes zoster with dissemination is significant in immunosuppressed patients, with 25%–45% of patients developing dermatomal zoster and a 10%–20% risk of developing dissemination without prompt and effective antiviral therapy 1.
- High-dose IV acyclovir remains the treatment of choice for VZV infections in compromised hosts, with oral acyclovir, famciclovir, and valacyclovir beneficial for mild cases or as treatment to complete therapy once the patient has shown a clinical response to IV acyclovir 1.
- Patients with disseminated VZV should also be started on antiretroviral therapy if not already receiving it, though this may need to be delayed briefly if there are concerns about immune reconstitution inflammatory syndrome.
Treatment and Prevention
- Treatment requires immediate intravenous acyclovir at 10-15 mg/kg every 8 hours for 7-10 days, followed by oral valacyclovir or famciclovir until lesions resolve.
- Vaccination may be considered for HIV-infected persons with CD4+T-lymphocytes count >200 cells/µL, with 2 doses administered 3 months apart, although data on use of varicella vaccine in HIV-infected adolescents and adults are lacking 1.
From the Research
Disseminated VZV and AIDS
- Disseminated varicella-zoster virus (VZV) infection can be a defining illness for AIDS, as it can occur in individuals with compromised immune systems, such as those with HIV infection 2.
- Severe, disseminated vaccine-strain VZV infection has been reported in immunocompromised individuals, including those with HIV infection, although it is rare 2.
- Disseminated VZV infection can present with symptoms such as diffuse rash, encephalitis, hepatitis, and pneumonitis, and can be life-threatening in immunocompromised hosts 3.
Treatment and Management
- Foscarnet has been shown to be effective in treating acyclovir-resistant VZV infections in patients with AIDS 4, 5.
- Antiviral therapy, such as acyclovir, valacyclovir, and famciclovir, is available to treat VZV infections, and new molecules are being developed to improve treatment options 6.
- Early detection and treatment of VZV infections are crucial in preventing severe disease and morbidity in immunocompromised individuals, including those with HIV infection 2, 3.
Immunocompromised Hosts
- Immunocompromised hosts, such as those with HIV infection, solid organ transplantation, and hematopoietic stem cell transplantation, are at increased risk of developing severe and disseminated VZV infections 3, 5.
- Clinician awareness of the risk of VZV infection in immunocompromised hosts and the availability of treatment options is critical in preventing and managing these infections 3, 6.