[Renal transplantation in children: punction-aspiration biopsy and renogram with 99mTc-DTPA]

Renal transplantation in children raises numerous diagnostic problems. The renography obtained with diethyltriaminopentaacetic acid marked with (99mTc metastable technetium (99mTc-DTPA) was compared with fine needle aspiration biopsy (FNAB) in search of a better interpretation of post-transplant crisis: rejection, acute tubular necrosis, toxicity by cyclosporin A and infection.

Sixteen acute post-transplant episodes were studied in 13 children submitted to renal transplantation. The post-transplant time was 6 days to 2.5 years. The basal renography and FNAB were carried out following the initial clinical manifestations and over a period of less than one week. The vascular and renographic phases were evaluated by interpreting the renography and were compared to previous renographies. The diagnosis of the aspiration biopsy was expressed as: normal, acute tubular necrosis, total necrosis, toxicity by cyclosporin A, viral infection and rejection.

Results agreed in 14 out of 16 cases: 1 normal, 3 acute tubular necrosis by renography and cellular necrosis by cytology, 9 rejections and 1 infection (increase in renal transit time). In the 2 cases with total necrosis of 100% followed by loss of renal allograft, the renographic diagnosis was severe vascular rejection with a negative prognosis.

In this series FNAB confirmed the renography as useful in the early diagnosis of complications which may appear in children undergoing renal transplantation.