A group of British physicians has reported in the medical journal The Lancet that giving the meningococcal C conjugate vaccine to children with nephrotic syndrome, a kidney disorder, may result in a relapse of their disease. The disease is believed to be caused by an abnormality of the immune system, and it has been shown in the past that stimulation of the immune system led to the syndrome, though researchers had never tested the effects of vaccines on nephrotic syndrome. Lead author Dr. Richard S. Trompeter, of Great Ormond Street Children's Hospital in London, found that relapse rates among nephrotic syndrome patients were higher after the children received the meningococcal C vaccine. That risk was especially higher in the first six months after vaccination.