hepatitis c and glomerulonephritis

my husband was diagnoses with hep c in 1996.  His liver biopsy indicated mild infection and his liver enzymes were mildly elevated (under 100).  He had a course of interferon and was considered in remission until 1998 and another round of interferon, and again in 1999 this time combined with remeron.  He was unable to take this medication due to anemia and psycotic episodes.  He finished interferon and his levels were less than 1500.  He has been monitoring his enzymes which have been perfect, no symptoms, that is until last month.  He had a very bad back pain, which he thought was a kidney stone.  He was told his urine protein in 24 h urine was 1850.  He went to nephrologist who ran a bunch of labs, again all perfect, except of course the protein, and igm a scant low.  He additionally ran a hep c viral load which was recorded in international units which threw us because we were not used to this type of number.  It just said over 850,000. So the nephrologist says well its from the hepatitis, go back to the gi doc.  The gi doc says hep c doesnt cause protein in the urine!  I tried to explain about the possiblity of mixed cryoglobulinemia, and i couldnt even get him an appt!  Can anyone out there help me with what to do?  Is this that unusual?  I also think he should have furthur testing done with all ive read online and live in NJ, anyone know of a good center for hep c treatment?  Thanks all for your input.