Horizontal transmission of hepatitis B virus (HBV) without apparent sexual
or parenteral exposure is common in hyperendemic areas. in most cases, the
route of transmission is unknown. To investigate urine as a potential sourc
e of infection, serum and urine from 56 chronic hepatitis B surface antigen
(HBsAg) carriers were examined for the presence of HBV DNA using the polym
erase chain reaction (PCR). Thirty-four of the patients were anti-hepatitis
B e antigen (anti-HBe) positive and 22 were hepatitis B e antigen (HBeAg)
positive. HBV DNA was detected in serum from 46 patients (82%) and in urine
from 28 patients (50%). Most HBeAg-positive patients had HBV DNA detectabl
e in urine (91%), whereas urine samples from anti-HBe-positive patients wer
e found to contain HBV DNA to a lesser extent (24%). When comparing HBV DNA
from serum and urine by an end-point titration PCR, a titration difference
averaging 10(3) was found between serum and urine. A significant female pr
edominance was also noted among the positive urine samples (P < 0.05), whic
h was not correlated to the presence of haematuria. Detection of HBV DNA ma
y indicate active viral replication, and thereby infectivity. Because a hig
h proportion of chronic HBV carriers were found to have HBV DNA in urine, i
t is suggested that irrespective of HBeAg/anti-HBe status, urine should be
regarded as a potential route of transmission and therefore be investigated
further as a means of horizontal and nosocomial transmission of HBV. J. Me
d. Virol. 60: 17-20, 2000. (C) 2000 Wiley-Liss, Inc.