In immunocompromised individuals, varicella-zoster virus (VZV) infections can be more severe in primary infections (varicella) and reactivated infections [herpes zoster (HZ)]. In individuals with varicella, cutaneous and visceral involvement can be more severe. In those with HZ, the infection may involve several contiguous dermatomes, have more extensive cutaneous necrosis, wide hematogenous dissemination to mucocutaneous structures as well as to the viscera, and often be associated with high morbidity and mortality rates.
Causes of Varicella-Zoster Virus Infections in the Immunocompromised Host
Immunocompromised patients may develop severe skin eruption with or without hemorrhage. Healing of the cutaneous lesions takes three times longer than in the general population. Patients develop high fever. Virus spreads to visceral organs causing hepatitis, pneumonitis, pancreatitis, small bowel obstruction and encephalitis. Bacterial superinfections including bacteremia can develop.
Symptoms of Varicella-Zoster Virus Infections in the Immunocompromised Host
- The lesions appear on the trunk and face and rapidly spread centripetally to other areas of the body.
- Skin infections including cellulitis can be caused by many bacteria, including Group A streptococcus, which can be severe.
- The presenting manifestations are rash, low grade fever and malaise. A prodrome may appear 1 to 2 days before in some patients. In healthy children, illness is generally benign, lasting 3 to 5 days. After the onset of the rash, malaise, pruritus, anorexia, or listlessness can develop.
Diagnosis
The diagnosis of VZV infection is usually based on clinical findings. However, in some situations, eg. immunocompromised patients, this can be difficult. In these patients, it is necessary to use laboratory exams to confirm the diagnosis.
Treatment
Systemic antiviral therapy Oral acyclovir, valacyclovir, famciclovir may be effective in some patients.
- In individuals with mild to moderate immunocompromise High-dose oral acyclovir, 800 mg five times daily for 7 days, hastens healing and lessens acute pain if given within 48 h of the onset of the rash. Large controlled studies in patients over 60 years of age have not, however, demonstrated any effect on the incidence and severity of chronic postherpetic neuralgia of high-dose oral acyclovir. A recent preliminary study of older patients (age 60) demonstrated a reduced frequency of persistent pain when IV acyclovir, 10 mg/kg q8h for 5 days, was given within 4 days of the onset of the pain or within 48 h after the onset of the rash.
Prevention
- Immunization VZV immunization is available and is 80% effective in preventing symptomatic primary VZV infection. About 5% of newly immunized children develop rash. Those at high risk for varicella who should be immunized include normal adults, children with leukemia, neonates, and immunocompromised individuals (immunosuppressive treatment, HIV infection, cancer).
- Antiviral agents for VZV- and/or HSV-seropositive individuals Undergoing BMT Acyclovir 400 mg PO bid, from the day of conditioning, induction, or transplantation for 4 to 6 weeks, suppresses both HSV and VZV reactivation.
References