Is Rituximab Suggestible For Increased Antibodies After Kidney Transplant?

Posted on Fri, 28 Mar 2014

Medically reviewed by Ask A Doctor - 24x7 Medical Review Team

Thu, 27 Mar 2014 Answered on

Thu, 24 Apr 2014 Last reviewed on

Question : My son, who is 30, has ARPKD and had his first kidney transplant at age 10 and then another one at 24. Both were from living donors. Well, now, six and half years into his second transplant, his microalbumin/urine is 604 and the ratio is 1793. Way too high, we know. His CR is 2.55 and BUN 57 and CR Clearance is 68.3 so his Nephrologist says his kidney function is stable for now. The chemo drug, Rituxin, has been mentioned to kill these antibodies that seem to be causing this issue. A biospy one year ago showed no rejection, just these antibodies attacking his tubules somehow. These numbers just went crazy within the last three weeks. Any other other ideas on how to treat this or what could have caused this huge jump in microalbumin? Any advice would be appreicated. A worried Dad.

Answered by Dr. Avinash Ignatius (6 hours later)

Brief Answer: Dear XXXXXX Detailed Answer: Every transplant induces antibodies and the level of antibodies increases with each subsequent transplant. Sometimes infections even simple viral infections can induce antibodies, leading to increased proteinuria. If he has had a recent viral infection which has settled, the proteinuria may subside over 4 - 6 weeks If he has recently been put on sirolimus or everolimus it may also increase proteinuria in some. If there is a recent sudden rise in proteinuria and doesn't subside , it warrants a biopsy even though a biopsy was done one year ago. If biopsy suggests that the problem is due to increased antibodies and is reversible then treatment options can be considered. Plasmapheresis or Rituximab would be an options if increased proteinuria is due to increased antibodies. Effect of plasmapheresis is however temporary and is used when a rapid reduction in antibodies is needed over a short period. Rituximab is better for the long term. Warm regards

Above answer was peer-reviewed by : Dr. Chakravarthy Mazumdar

Follow up: Dr. Avinash Ignatius (6 hours later)

Dr. XXXXXXX Thank you, your reply was very helpful. His Nephrologist is considering Rituximab but the others in his practice are trying to be more conservative because my son has a two year who brings home many weird childhood colds, etc. that are normal for that age. They are worried that he would be even more immune suppressed with Rituximab. Is that a danger? Also, I didn't know that each transplant increases the antibodies. I would imagine my son will need another transplant one day. Will he be able to have another one or even a fourth one if necessary? It seems as though these transplants only last about 10 years on average. Thank you for your time and advice.

Answered by Dr. Avinash Ignatius (21 hours later)

Brief Answer: Dear XXXXX, Detailed Answer: Yes it is true that Rituximab will reduce his immunity. There would be an increased risk of getting an infection. Also a bug causing a simple cold in a healthy person could cause a much severe infection. It is a matter of balancing the risks vs benefits, for that reason I feel that a graft biopsy would help in deciding as how much of the damage is likely to be reversible or not. Unless his creatinine has risen recently, his creatinine clearance is unlikely to be more than 40 -45 at a creatinine of 2.5. Rituximab would be of use only if there is a significant scope of improvement, otherwise the risks wouldn't be worth it. It is a decision only his treating nephrologist can take. Also generally with each transplant, due to sensitization more and more antibodies are produced and usually the subsequent transplant kidney lasts for a shorter period than previous - (though exceptions are always there) There are a number of examples who have undergone a third and even a fourth transplant. It not impossible . . . Warm Regards

Above answer was peer-reviewed by : Dr. Chakravarthy Mazumdar