Serotesting versus presumptive varicella vaccination of adolescents with anegative or uncertain history of chickenpox

Objective: To review the current practice of adolescent health care provide rs when an adolescent reports a negative or uncertain history of chickenpox in order to provide information for future practice. Methods: Retrospective chart review of a sample of patients seen in a hospi tal-based adolescent primary care clinic between 1996 and 1999. Results: Among adolescents who reported a positive history of chickenpox (1 90 patients, aged 15 +/- 1 years), varicella occurred before age 5 years in 30%, between 5 and 10 years in 56%, and at older than age 10 years in 14% of the patients. When adolescents reported a negative or uncertain history of varicella (55 patients, aged 15 +/- 1 years), serotesting was ordered fo r the majority (73%) of cases, while only 16% were presumptively vaccinated with varicella vaccine. In six patients no intervention was noted in the c harts, and these patients were contacted. In 80% of the patients who were s erotested, varicella IgG titers of greater than or equal to 1:32 indicated a previous unnoticed infection and lifelong immunity to varicella. In only 20% of the patients sera were negative for varicella IgG titer, requiring v aricella vaccination. There was no statistical difference between the numbe r of siblings of patients with a positive serologic test (3 +/- I) and the number of siblings of seronegative patients (2 +/- 1, p = 0.41). Seven of t he eight seronegative patients consented to varicella vaccination and were vaccinated within 10 months of serotesting. Conclusions: These data support the practice of serotesting for a previousl y unnoticed varicella infection rather than presumptive vaccination in the adolescent age group. A follow-up vaccination of seronegative adolescents s hould be scheduled as close to serotesting as possible. (C) Society for Ado lescent Medicine, 2000.