The Management of Varicella and Zoster Infections

Sequential use of intravenous and oral acyclovir in the therapy of varicella in immunocompromised children

BACKGROUND

Immunocompromised children are at risk for disseminated varicella infections. Standard management involves hospitalization and intravenous acyclovir for 7 to 10 days. This approach is expensive, is inconvenient and may not be necessary. We undertook a pilot study to assess the safety and efficacy of an alternative approach that utilized a combination of intravenous (i.v.) followed by oral (p.o) acyclovir in a cohort of immunocompromised children.

METHODS

The cohort consisted of 26 immunocompromised children between the ages of 1.5 and 12.7 years (mean, 6.3). Therapy was commenced with i.v. acyclovir (1500 mg/m2/day in 3 divided doses). Concurrent management included holding or reducing immunosuppressive therapy (by 50%) and administering varicella-zoster immunoglobulin in 69% (11 of 16) of cases where exposure to chickenpox was recognized. Patients were eligible to switch to p.o therapy after receiving a minimum of 48 h of i.v. acyclovir therapy provided they were afebrile; had no new lesions for 24 h; had no internal organ involvement and were able to tolerate oral medications. Patients were observed in hospital for a further 24 h and then discharged provided they remained well. Oral acyclovir was continued for a total of 7 to 10 days (i.v. plus p.o).

RESULTS

Of the 26 patients 25 were successfully switched from i.v. to p.o after 4.1 +/- 1.2 days (mean +/- SD) (range, 2.3 to 6) Children had fever for a mean of 2.0 +/- 1.6 days (range, 0 to 5) and developed new lesions for 2.9 +/- 0.7 days (range, 2 to 4). All 25 patients switched to p.o therapy had resolution of their disease and no patient required resumption of i.v. therapy.

CONCLUSIONS

The sequential use of i.v. followed by p.o acyclovir is feasible in the treatment of varicella in immunocompromised children and results in a reduction in duration of intravenous therapy and hospitalization.

Treatment of varicella in the immunocompetent adult

Varicella in the immunocompetent adult is an infrequent but potentially serious infection. Previous studies in immunocompetent hosts and normal adults have demonstrated the value of intravenous acyclovir in the treatment of varicella-zoster virus infections. Oral acyclovir has also shown efficacy in both normal adults with zoster (shingles) and immunocompetent children with varicella. A recently completed double-blind placebo-controlled study of oral acyclovir in immunocompetent adults with uncomplicated varicella also demonstrated efficacy. Therapy within the first day reduced the time to 100% crusting of skin lesions from 7.4 to 5.6 days, and reduced the duration of fever by one-half day. Symptoms were also diminished. These benefits were observed only when therapy was initiated within 24 hours of the appearance of the rash. Adults with complicated varicella (usually symptomatic varicella pneumonia) should receive intravenous acyclovir. Several new agents for varicella-zoster therapy are being evaluated; brovavir is a new agent currently being compared to placebo in the treatment of adult varicella.

Infectious complications in childhood acute leukemias

Infectious complications in children with acute leukemias are reviewed as to incidence, predisposing factors, microbiologic etiologies and treatment. Principles of antimicrobiologic therapy are presented for bacterial, fungal, viral, and protozoal infections seen in children with cancer. Prevention of infection is also discussed.