Background: When varicella develops in a susceptible child during corticosteroid therapy for nephrotic syndrome, it is associated with significant morbidity. Susceptibility to varicella is usually defined by low or undetectable antibody levels.Case Report: Varicella developed during a relapse of nephrotic syndrome in a boy who previously had protective varicella specific antibodies. The reinfection was characterised by the development of varicella IgM levels with a further rise of the varicella IgG levels. The child made a full recovery following discontinuation of corticosteroids and administration of Acyclovir. Conclusions: The determinants of immunity to varicella are discussed. Our findings suggest the need to reassess the clinical guidelines regarding the risk of varicella in nephrotic syndrome as reinfection may occur despite the earlier presence of protective antibodies.

Keywords: Chickenpox, nephrotic syndrome, Antibodies, viral