Safety aspects and diagnostic findings of serial renal allograft biopsies, obtained by an automatic technique with a midsize needle.

Percutaneous biopsy is an important diagnostic procedure in evaluating the renal allograft with compromised function. Graft losses and haemorrhagic complication are major risks. To minimize these problems we used a midsize TruCut needle, controlled by an automatic firing device (Biopty-Cut), fixed to an ultrasound guidance system. Core biopsies of 1.2 x 20 mm were obtained from 1,421 kidney grafts. On 5 occasions a haemorrhagic complication that required prolonged hospitalization or intervention occurred. No grafts were lost as a consequence of the biopsy procedure. Typical histological morphological parameters found during allograft rejection has earlier been established. Using a protocol with 27 histological parameters this study confirms that recognized criteria for rejection can be relied upon even with this smaller needle. The results showed that the degree of oedema and lymphocytic infiltration of the interstitium and in the arterial wall discriminated best between rejecting grafts and non-rejection grafts.