Interview with Prof Vincenzo Cambi

Prof Vincenzo Cambi Head, Department of Medicine and Nephrology Full Professor of Nephrology University of Parma, Italy

Prof Zoccali: In the early seventies you were the first to propose an intensive use of dialysis units and short dialysis. Your proposal was rapidly adopted worldwide and became the standard method. In the following years, particularly in the last decade, experience has shown that long dialysis and frequent treatment schedules (daily or 4-5 times per week) have distinct advantages in terms of cardiovascular complications. How do you think that the advantage of long or more frequent dialysis can be combined with the need of treating a progressively increasing number of patients in saturated dialysis units?

Prof Cambi: The concept of short dialysis was originated by the studies on low-flow dialysis made in 1969-71 in Seattle under the direction of Belding Scribner (Tr. ASAIO 1971). Actually in the early seventies the offer of dialysis treatment was much lower than the request and to be accepted in a dialysis program was the “privilege” of a minority of patients. Thanks to short dialysis we began treating, in 1972, six patients per dialysis station, the offer increased three times this number and we therefore dialyzed patients living 100-200 km from our Units because of the lack of dialysis facilities in Italy. Everybody, including the patients, was aware of the problem of fluid overload. On the other hand isolated UF was unknown as well as easy manipulation of the extra fluid volume. Because of these premises the discipline in our Unit was very rigid: the patient was allowed to gain ½ kg/day: i.e. 1 ½ kg during the week-end interval! Unstable patients were treated three hrs. every other day, obviously including Sundays (EDTA Proc. 1973): this method is still used routinely in our Unit. That’s why we were not surprised by the great advantages offered by more frequent dialysis sessions. How to deal with the problem of the continuing increase of the dialysis population? The only solution I know is an individual hardware, highly automatized, equipped with technology for reprocessing filters and lines. Obviously the best allocation is the patient’s home. If this is not possible, we should have special areas in hospitals, or limited care centres, with reduced nursing assistance: e.g. one nurse every 10 patients maybe with the cooperation of a family member of one or more patients.

Prof Zoccali: The introduction of Kt/v represented the first real attempt at quantifying the dialysis dose. Do you believe that nephrologists are becoming too trusty of this index? Should we formulate new, more articulated indicators of dialysis adequacy, incorporating other fundamental treatment goals such as correction of fluid volume overload?

Prof Cambi: By increasing the Kt/V, the risk of death for a dialysis patient drops and reaches a plateau when Kt/V is about 3.6 with a standard three times weekly dialysis schedule. A further increase of Kt/V will provide only marginal effects on pre-dialysis peak concentration of toxic solutes, because it mainly depends on their generation rate, unaffected by dialysis, and the inter-dialysis interval. At steady state, urea removal is in fact always the same, independently of Kt/V, and the only way to reduce urea accumulation is the reduction of the inter-dialysis interval with more frequent treatments. The accompanying positive effect is not only a reduced pre- and post- dialysis fluctuation of urea, but also pre- and post- dialysis fluctuation of fluid, solutes acid-base, with foreseeable improvement of clinical symptoms. In the latest years the independent role of the variable “t” in the Kt/V equation has emerged both in terms of solute removal and tolerance to weight loss. Now it is time to consider another variable of no lesser importance: the inter-dialysis interval.

Prof Zoccali: The DOPPS study is a tremendous effort aimed at comparing dialysis practices worldwide. An important difference between the USA and European countries is the proportion of patients starting dialysis with a functioning AV fistula. In Italy most dialysis doctors have gained a great expertise in AV fistula surgery. Do you feel that AV fistula surgery should be included in the formal training of nephrology?

Prof Cambi: Yes, I absolutely do. However we should distinguish between standard distal AV fistula, which was the best standard thirty years ago, the present proximal AV fistulas, which require much more skill but can be performed by an expert nephrologist within the renal area, and complicated artificial vessel, (prothesis and first of all emergencies - e.g. explosions of proximal prothesis) which require the operating room and skilled surgeons. In other words the nephrologist should be prepared to face daily routine and daily “standard” emergencies, e.g. AV fistula obstruction. A skilled vascular surgeon, perfectly aware of the specific problems of a dialysis patient, should always be available for emergencies.

Prof Zoccali: For almost two decades you have been a dedicated officer to the ERA-EDTA and you are perhaps the person who has contributed more to build a solid society now including more than 95 countries. Which were the main challenges of the ERA-EDTA in the years when you served as Secretary-Treasurer and Chief-Controller?

Prof Cambi: I served as Secretary-Treasurer and later as a Chief-Controller between 1990 and 1999.
In 1990 I found a ‘stagnant’ Association. Members were approximately 2,000, abstracts per congress about 1,000, congress registrants about 3,000. The income of the Association was hardly sufficient to pay for the Journal (NDT) and to support the Registry. A disproportional amount of the Congress profit was flowing into the accounts of the congress organizers (the so-called Professional Congress Organizers). In addition the social and scientific organization of the Congress was strictly controlled by the congress President (and sometimes by the whims of the Congress President). It appeared absolutely necessary to reorganize the membership office with a dedicated person as well as the administration of the Society. It appeared also obvious that leaving the congress profit in the hands of a PCO was a financial suicide for the Association. A detailed project for the creation of a specific congress office was presented to the Council. The final decision was taken by the Council in the summer of 1992 (Paris) after a difficult debate lasting several hours (the council ended about midnight). Little by little a group of highly motivated and cultivated young ladies joined the new Congress Office, based in Parma and, with their fundamental contribution, we started the direct management of all the administrative branches of the Association, including the Congress and Membership aspects. In the course of the years the new Council members and officers appeared more and more stimulated by the active environment surrounding the Association. The present scientific and financial success is continually implemented by the continuing and original initiatives taken by the present, young generation of Officers and Council members (e.g. NDT-Educational, CME programs, research fund, etc.).

Prof Zoccali: There is tendency in the Scientific Community to organize joint congresses with related societies. The World Congress of Nephrology, a joint effort of the ERA-EDTA and the ISN, has been a success in this respect. Do you feel that an effort should be made to increase joint efforts of this kind?

Prof Cambi: Yes. However the roles of the host and the guest must be unequivocal. At present the Association and the congress are successful, but, first of all, totally self-sufficient. The association has the scientific and financial strength to support outstanding scientific and educational initiatives on its own.
It seems unfair to me for a guest to be co-opted in our congress organization and then willing to share our rights and to dilute 50/50 our scientific and organizational image.

Prof Zoccali: Your main scientific and clinical interests are now on renal transplantation. Which is the next target for a clinician to improve the already successful clinical results?

Prof Cambi: At present acute rejection has become a very limited problem. On the contrary chronic allograft nephropathy and long-term metabolic damages are, in my opinion, the most important problem to be addressed at the present. There are several immunosuppressive drugs available, some of them with profoundly different pharmacologic activity. At present our approach to drug therapy for chronic rejection has been deeply revisited. The long-term reduction of anti.calcineurins and steroids certainly limits nephrotoxicity and metabolic damages. New drugs may further diminish or abolish what in the immunosuppressive therapy is not strictly beneficial.

Prof Zoccali: Do you believe that xenotrasplantation and/or kidney cloning will be feasible in 10 years or so?

Prof Cambi: Certainly research is speeding up and in ten years’ time this kind of future seems realistic. However we cannot forget that the concept of tolerance has become a scientific reality only in the last ten years and at present, we only have the feeling of being just at the beginning of a “new immunologic era” at least on an experimental basis, not yet on sound clinical grounds. However the preliminary results of the most recent clinical papers raise the possibility that clinical experience, i.e. the concept of “maintenance minimization”, might bring forward some application of proper clinical tolerance. The future of xeno-transplantation is strictly connected to the problem of chronic rejection and tolerance. Advances in understanding the cause and treatment of chronic rejection may be transferred to xenotransplantation and probably the hyperimmune patients might become the first convenient clinical application. The number of studies in organogenesis is very encouraging and a clinician can only take advantage of so many different sources of knowledge.

Prof Zoccali: You are a thoughtful teacher. Which is the basic advice you give to nephrology trainees in your department?

Prof Cambi: Clinical research is not an exclusive matter of the “Scientist”, but is the daily duty of each trainee. In our Department each trainee is always invited to express and defend his/her documented opinion and the electronic library of our University offers a large choice of Journals. An opinion related to diagnosis and treatment of a patient, especially if coming from a trainee, is always discussed and taken into consideration. Each trainee should learn during the five years of the post-graduate school that professional knowledge is an every day effort and needs uninterrupted studying and continuing confrontation with the senior staff.

Prof Zoccali: You live in Parma, which is a European capital for high quality food. Which is the reason of this peculiar identity?

Prof Cambi: The Parma area is also known as the “food valley” of Italy, not only because of the tradition of Parmesan cheese - Parmigiano Reggiano (already used by ancient Romans but recognized for its unique flavour only later at the end of the XIV century) but also for the unique technique of processing pork (Parma ham is only one example). In fact, in our area, there is one of the largest European concentrations of food Industries (especially pasta and dairy products) and manufactures specialized in building machines for food processing. Certainly the worldwide request of our main specialties has probably been the main driving force of the food Industry.

Prof Zoccali: You have a talent for cooking and are considered a cuisine expert. Do you have a specific interest in any special dish?

Prof Cambi: Let me say that I find cooking great fun: it forces you to devote all your attention to what you are doing; the alternative might be poisoning your guests! Cooking is also my preferred way to meet friends. I always cook Italian and Mediterranean recipes. I am against experimenting with exotic ones: in fact, for an Italian amateur, trying to badly imitate centuries of foreign culture is, in my opinion, a nonsense. Cooking is also exhibitionism with distinct psychiatric trends. This is why I always present my guests with small portions of different recipes like in a Circus. In doing that I use minerals, vegetables and animals of various kinds, going from finger food to elaborate pastry dished. More recently I have been intrigued by the technicality of pastry-making: you can easily forecast a perplexing future for my family and my guests.
Wine is obviously one of the leading actors of a dinner, not only for accompanying different foods, but it also allows the host be forgiven by his guests when needed. Nobody is perfect…