Combination fine-needle aspiration cytology and intrarenal manometry at the onset of renal dysfunction

Twenty-three consecutive cadaveric renal allograft recipients immunosuppressed with cyclosporin have been monitored three times a week by fine-needle aspiration cytology and intrarenal manometry until discharge from hospital or until 30 days post-transplant. Standard criteria were used to determine the cause of allograft dysfunction. The onset of allograft rejection was marked by an elevation of the total corrected increment score by fine-needle aspiration cytology in 80 per cent of rejection episodes whereas intrarenal pressure was raised in only 46.6 per cent. However, intrarenal pressure was greater than 40 mmHg on a single occasion in 16 measurements performed on allografts showing evidence of cyclosporin nephrotoxicity. By combining fine-needle aspiration cytology and intrarenal manometry the sensitivity of these tests for allograft rejection was increased to 93.3 per cent at the onset of renal dysfunction. Our results demonstrate that fine-needle aspiration cytology is more sensitive than intrarenal manometry as a single investigation. However, the combined test may have an important role in the differentiation of allograft rejection and cyclosporin nephrotoxicity in the early management of renal allograft recipients.