[Complications and costs associated with chickenpox in immunocompetent children]

Chickenpox is a common infection of childhood in countries that have not included the corresponding vaccination in their immunization schedules. Chickenpox is usually benign in immunocompetent children, and treatment is not needed. The objectives of this study were to investigate the frequency and characteristics of chickenpox complications that require hospital treatment in immunocompetent children and the clinical progression in children of mothers with perinatal chickenpox. In addition, the hospital costs associated with chickenpox in the studied children were calculated.

This was a retrospective study using the clinical records of children with chickenpox hospitalized at the Children's Hospital of Panama, from January 1991 through December 2000. We analyzed the types of complications, the clinical progression, and the hospital costs of the chickenpox patients.

Of 5 203 children seen in outpatient consultations, 568 of them (11%) were hospitalized. We included 513 children in our study: 381 (74%) with chickenpox acquired in the community, 92 (18%) the children of mothers with chickenpox, and 40 (8%) with nosocomial chickenpox. The most frequent complications were cutaneous and subcutaneous infections (45%), respiratory infections (25%), and neurological changes (7%). The respiratory and cutaneous complications occurred sooner and among younger patients than did the neurological changes. Overall, 13 of the children (2.5%) died. The case fatality rate was 8% for chickenpox with respiratory and neurological complications and 0% for chickenpox with cutaneous complications. Of the 92 children with a mother with chickenpox, 60 of them (65%) did not develop the disease, and none of the 92 died. In contrast, 2 of the 32 neonates (6%) with perinatal chickenpox died. The mean length of hospitalization was 8.9 days (standard deviation, +/- 17.4 days). Parenteral pharmacotherapy was used with the great majority of the children, particularly antibiotics (54%), acyclovir (17%), and intravenous immunoglobulin (14%). The mean per-patient cost of hospitalization was US$ 1 209.

Our results show that chickenpox is associated with a sizable number of expensive complications and a not-insignificant case fatality rate in immunocompetent children. Routine vaccination against chickenpox could reduce the impact of this disease on the health of children in Panama