HCV CONFUSION

HELLO EVERYONE,
I AM VAIBHAV.
MY FATHER IS A CKD PATIENT.IN 1997 HIS KIDNEYS FAILED AND HE WAS ON DIALYSIS.
IN 1998 HE WENT FOR A TRANSPLANT.JUST A DAY BEFORE THE TRANSPLANT SGOT,SGPT>1000.
DOCTOR DIDN'T UNDERSTAND WHY IT IS SO HIGH AND THE TRANSPLANT WAS POSTPONED.HCV WAS NOT DETECTED IN HCV-ELISA TEST.
A YEAR LATER A DOCTOR SUSPECTED THAT IT WAS HCV AND HE ASKED US TO GO FOR HCV RNA.THERE IT WAS CONFIRMED THAT IT IS HCV POSITIVE.
LATER HCV ELISA ALSO SHOWED THAT IT WAS HCV POSITIVE.
IN 2000 HE WENT FOR TRANSPLANT AS HIS SGOT,SGPT WAS AGAIN NORMAL.
HIS TRANSPLANTED KIDNEY WORKED WELL FOR 10 YEARS.
HE IS ON DIALYSIS ONCE AGAIN FOR AN YEAR NOW.
BEFORE DIALYSIS IN SEP 2010 HCV ,HBSAG AND HIV TEST WERE CONDUCTED AND ALL OF THEM WERE NEGATIVE.
WE THOUGHT HCV IS NEGATIVE AGAIN.
BUT 2 DAYS BACK WE GOT THESE TEST'S DONE AND IT SHOWS HCV REACTIVE AGAIN.
I AM CONFUSED IF THIS IS BECAUSE OF INFECTION FORM OTHER DIALYSIS PATIENTS OR IT IS JUST THAT HCV ELISA METHOD IS NOT VERY ACCURATE.