Universitätsklinikum Charité, Med. Klinik m. S. Nephrologie, Berlin, Germany. Email: Lutz.Fritsche{at}charite.de
Sir,
The paper by Zeier and Ritz in the April 2002 issue of NDT [1] is a good reminder of the importance of evaluation and selection of kidney transplant candidates. Also, this paper clearly demonstrates the persisting lack of clinical evidence in this field, which has considerable impact on large numbers of end-stage renal disease patients.
We have previously demonstrated the unexplained variations in the evaluation and selection of transplant candidates across Europe [2]. These variations were especially large in areas with conflicting or lacking evidence. Since our investigation, in Europe as well as in America, guidelines were compiled according to the current standards of guideline production [3,4]. Each recommendation in these guidelines is related to the available evidence in a transparent manner. For several important issues in the preparation of transplant candidates, these guidelines give no recommendations due to the determined lack of evidence.
In contrast to these guidelines, the paper by Zeier and Ritz aims to cover all aspects of preparing candidates for kidney transplantation. Consequently, along with warranted and relevant points for which convincing evidence is cited, the paper by Zeier and Ritz contains a number of recommendations which are mere opinions of the (expert) authors and should be clearly separated from the other contents of this useful paper. We would therefore like to comment on a few of these opinion-based recommendations.
The evaluation of iliac and lower extremity vessels is of obvious importance, but which examination is appropriate cannot be determined from published studieswe are aware of only one study and it evaluated only angiography [5]. In our centre we therefore perform a pelvic X-ray (instead of duplex sonography or angiography as recommended by Zeier and Ritz) to screen for iliac/femoral vascular calcifications. The value of this approach is evident: no calcification on the X-ray, no arterial calcification. If calcifications are present or peripheral vascular disease is suspected, the only orientation is personal clinical experience. We are not aware of any study about the correlation between duplex or angiographic findings and the risk of post-transplant ischaemia in the ipsilateral leg.
The recommended search for sinus infections and dental root abscesses is an additional burden for the patient without any proven benefit. In the hundreds of patients we have seen in our centre, we can recall only one patient with an acute sinusitis in the early post-transplant period and no problems with dental abscesses at all. Consequently, we have discontinued these investigations in our centre, so far without any apparent detrimental effect.
Why vesico-ureteral reflux should be excluded prior to transplantation is not stated by the authors. The diagnostic procedure required is uncomfortable and potentially hazardous for the patient. The implied risk of infections is not, and from our experience cannot be, substantiated by clinical data.
We absolutely agree with the authors that an attempt to cure viral hepatitis before transplantation should be undertaken, but how the hepatic prognosis' can be accurately assessed by pre-transplant liver biopsy without epidemiological data on the prognostic implications of the histological findings mystifies us. It should also be noted that the quoted excess mortality related to persisting hepatitis B infection is in comparison to other transplant recipients; we are not aware of data that suggest better survival for hepatitis B-infected dialysis patients.
The recommended waiting period of 5 years after any malignancy, except spinocellular carcinoma, contrasts the period of only 2 years recommended by other authors [6]. The statement that there is consensus about the extreme approach of a 5 year waiting period is wrong: the European best practice guideline published in 2000 in NDT [3] recommends 2 years waiting for most cancers, the same is true for the American guideline [4].
We feel that these and other points challenge the transplant community to extend the scientific basis of current care for kidney transplant candidates. Thus, we would like this letter to be interpreted not as criticism of the paper by Zeier and Ritz but as support for their intent to increase the transplant community's awareness of this important field.
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