Arthritis and vasculitis are very rare complications of varicella occu
rring almost exclusively after the eruption of the characteristic rash
. We report two children, aged three and seven years, who developed va
sculitis and polyarthritis (patient No. 1) and arthritis (patient No.
2) 13 and 9 days, respectively, before the onset of their typical vari
cella. Arthritis and vasculitis so early in the incubation period of v
aricella have not been described previously. In all previously reporte
d cases the arthritis occurred after or together with the onset of var
icella and only in one instance preceded the exanthem by 2 days. Altho
ugh this may have been an unfortunate coincidence, an association betw
een varicella tester virus and these manifestations should be seriousl
y considered. Clinicians confronted with such cases must be cautious a
nd search for varicella infection, especially in times of epidemics.