- Email: [email protected]
Ethical considerations in feline renal transplantation
The Veterinary Journal 202 (2014) 405–407
Contents lists available at ScienceDirect
The Veterinary Journal j o u r n a l h o m e p a g e : w w w. e l s e v i e r. c o m / l o c a t e / t v j l
Personal View
Ethical considerations in feline renal transplantation ☆ James W. Yeates * RSPCA, Wilberforce Way, Southwater, Horsham, West Sussex RH13 9RS, United Kingdom
A R T I C L E
I N F O
Article history: Accepted 8 October 2014 Keywords: Feline Renal Kidney Transplantation Ethics Surgery Veterinary
Introduction Chronic kidney disease (CKD) is very common in cats, especially in cats over 7 years of age. It can be caused by many conditions, including tumours, infections and polycystic kidney disease; the latter being particularly common in Persian cats. One treatment option that is available in some countres is feline renal transplantation, which involves the implantation of a kidney from a ‘source’ cat into a ‘recipient’ cat. Cats can tolerate transplantation from unrelated animals of the same species, using immunosuppressive drugs, such as cyclosporine, to reduce rejection risks. Affected cats are assessed for suitability, stabilised on fluid therapy and treated for hypertension (Bernsteen et al., 2000; Adin, 2002; Pressler, 2010). Potential source cats must also be assessed for suitability (they are usually young, healthy cats), and they are then anaesthetised and have a single kidney removed. The transplant is implanted in the recipient cat through vascular surgery under anaesthesia, with the original kidneys usually left in place. The kidney may be obtained from shelter cats destined for rehoming. Other sources, including recently deceased cats, purposebred cats and biotechnical solutions (such as cloning) are not discussed here. Feline kidney transplantations have been performed since the 1980s for cats with CKD (Gregory, 1993; Mishina et al., 1996;
☆ Please note that the content in this Personal View article has not been subject to peer-review. The views expressed in this Personal View are entirely those of the author and do not necessarily reflect those of the editorial team, or Elsevier. * Tel.: +44 3001230129. E-mail address: [email protected].
http://dx.doi.org/10.1016/j.tvjl.2014.10.006 1090-0233/© 2014 Published by Elsevier Ltd.
Mathews and Gregory, 1997). Nevertheless, it remains a controversial treatment option and views on its acceptability differ among clinicians and countries. For example, transplantation appears to be permissible in Australia, New Zealand and the USA under particular conditions1. In the UK, the procedure was permitted in 20032, but in 2013 authority was suspended pending a review3. Also in the UK, the Royal Society for the Prevention of Cruelty to Animals (RSPCA) considers that the practice may be illegal as it causes unnecessary suffering (Chapman, 2014). Veterinary surgeons and rescue centres therefore face difficult decisions regarding the procedure and in judging whether to perform transplantation to and from identified cats in specific cases. Currently, kidney transplantation is relatively rarely performed in cats. However, because kidney disease is so prevalent, it is likely that the procedure may become more frequent and it is with this possibility in mind that the present article has been written. There are two main concerns. The first is the harm/benefit in terms of suffering and lifespan, which may be affected by medical diseases, treatment and kennelling (Yeates, 2012, 2013). Both are important elements of veterinary work, although the value of the
1 New Zealand Veterinary Association Guidelines, 2010. http://www.nzva.org.nz/ sites/default/files/policies/9i%20-%20Renal%20Transplantation%20-%20Mar10.pdf (accessed 15 August 2014). Feline CRF Information centre, 2013. Feline Kidney Transplant Facilities. http://www.felinecrf.com/transb.htm (accessed 29 August 2014). 2 RCVS, 2003. Guidelines Approved for Kidney Transplantation in Cats. https:// www.rcvs.org.uk/news-and-events/news/guidelines-approved-for-kidneytransplantation-in-cats/ (accessed 15 August 2014). 3 RCVS, 2013. Miscellaneous. https://www.rcvs.org.uk/advice-and-guidance/codeof-professional-conduct-for-veterinary-surgeons/supporting-guidance/ miscellaneous/ (accessed 15 August 2014).
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J.W. Yeates/The Veterinary Journal 202 (2014) 405–407
latter assumes that the former has been achieved, i.e. a longer life is valuable only if the cat will have a good quality of life (Yeates, 2010a). The second concern we might call ‘cat-likeness’, analogous to concepts such as ‘telos’ (Rollin, 1981), referring to the degree to which a cat meets its species identity; anything that makes it less like a (normal) cat reduces its ‘cat-likeness’. This concept can relate to morphology (e.g. number of body parts) or to function (e.g. biological processes). Recipient cats CKD tends to be progressive, incurable and potentially fatal. The main problem in affected cats is the reduced ability of the kidney to remove toxins from the blood and to adequately concentrate the urine. This may be associated with adverse effects on the wellbeing of cats related to the pathology (e.g. nausea, thirst and malaise) or arising from the medical treatment (e.g. from hospitalisation and transportation), and with a shortened life expectancy, given that it is a terminal condition which usually presents clinically at a late stage (stages 3 or 4). Treatment usually involves supportive care and dealing with any clinical signs; it includes dietary change, use of phosphate binders, medical blood vessel dilatation, and treatment of dehydration, high blood pressure, anaemia and vomiting. Euthanasia may be required in advanced cases. In cats, kidney implantation can reduce the distress of CKD (Schmiedt et al., 2008). However, it can also lead to post-operative pain and there is a risk of complications, such as transplant rejection, infections (Bernsteen et al., 1999), retroperitoneal fibrosis (Aronson, 2002; Wormser et al., 2013), hypertension (Kyles et al., 1999), neoplasia (Wooldridge et al., 2002) and diabetes mellitus (Gregory et al., 1997; Case et al., 2007; Gregory, 2007). Kidney implantation may shorten a cat’s life through peri-operative mortality (Adin et al., 2001) or may extend a cat’s life, perhaps for several years (Schmiedt et al., 2008). The veterinarian therefore must gamble between relatively predictable deterioration and short-term effects on the well-being of the animal, followed by a longer life in better health of unknown duration. This gamble is especially difficult because it relies on limited scientific information (Roudebush et al., 2009). There will also be different odds for different cats, as recipients may be affected by kidney disease or by a particular medical treatment in different ways. For example, some animals may have other concurrent diseases that would cause clinical signs or shorten life anyway. Perhaps most importantly, the cat’s future quality of life depends on the owner, who needs to be able to cope with the likely progression of CKD versus the costs of treatment, including ongoing immunosuppression and, if they adopt the cat whose kidney is implanted, the demands of keeping a second cat for many years, and on the patient’s tolerance of that cat. Each particular case therefore requires a tailored evaluation. It can be argued that adding an exogenous kidney somehow detracts from the individual animal’s ‘cat-likeness’. Certainly, most cats have two kidneys, whereas kidney recipients generally finish with three. Furthermore, the additional kidney may be thought to enhance the cat’s overall function above that of normal cats. However, I find this argument less convincing than it immediately appears. Firstly, the implantation of an additional kidney can be thought of as merely a substitution by a replacement kidney (even if the original kidneys are left in situ); this would be analogous to treatments such as insulin for diabetes. Secondly, if we consider that the decreased function of the original kidneys is due to abnormal pathology or problems from cat breeding, then the new kidney is simply maintaining normal function. In neither case is the cat necessarily better than normal. Theoretically, it might be possible to perpetuate a cat’s lifespan or increase its function well beyond normal, but such cats would constitute categorically different cases.
Potential source cats It can also be argued that a source cat is made less ‘cat-like’ by ‘mutilations’ that remove a body part, in this case a kidney. However, this argument also has limited force. The value of a body-part seems to depend on its function (consider human appendices); it seems hard to defend the view that lacking non-functional anatomy is intrinsically bad. Losing one kidney may not have any major effect on kidney function, since most cats have ‘spare capacity’ that allows overall renal function to be unaffected by having a single kidney. Only if pathological or degenerative changes reduce the functional capacity of the remaining kidney below its spare capacity, will the absence of a second kidney then reduce overall renal function. In a small scale evaluation of the long term (24–67 months) effects of unilateral nephrectomy in 16 healthy source cats, one cat was diagnosed with chronic renal insufficiency at 52 months postsurgery (Lirtzman and Gregory, 1995). Given the prevalence of CKD, this risk does not appear to make source cats ‘less cat-like’. Rather, the functional significance of this change is best assessed by considering its clinical effects. In actuality, the removal of a kidney is likely to cause some adverse effects on well-being. Pre-surgical testing and preparation may involve moderately unpleasant experiences of transportation, hospitalisation, handling, venepuncture and sedation. Surgical complications may result in more substantial acute suffering. Any later kidney disease may worsen more quickly. These risks mean that, in general, and all other things being equal, nephrectomy can be expected to reduce the mean (but not necessarily median) well-being and life expectancy. Again there is a gamble, the value of which depends on what would otherwise happen to the source cat. In particular, would it suffer and die for some other reason? Of particular importance here is whether the animal would undergo long term kennelling or euthanasia in a shelter. Several shelters in the USA run schemes in which owners of cats with renal disease can adopt a shelter cat, which provides a kidney to their prior cat and which itself is rehomed to an owner who cannot get the kidney without rehoming the donor cat. The cat thereby gets rehomed, albeit at the cost of a kidney, and saved from euthanasia. Of course, the transaction is not beneficial if the owner then unscrupulously euthanases or neglects the adopted cat, or if the source cat were to be rehomed anyway, either to another adopter (as many young, healthy cats are often popular with adopters) or to the owner of the potential recipient (if they could adopt that cat anyway). However, rehoming one cat may affect the rehoming of other cats, where charities are faced with more animals requiring their care than there are adopters willing to rehome. On the plus side, rehoming a source cat that would have been rehomed anyway ‘frees up’ an adopter to adopt another cat. On the minus side, if the source cat is adopted by someone who would otherwise have adopted another cat, then the source cat ‘uses up’ that adopter, perhaps indirectly leading to the euthanasia of another cat, with no net benefit.
Implications for kidney transplantation decision-making Each veterinary surgeon has a duty not to harm a patient unnecessarily, even for the benefit of another animal (Yeates, 2009). This means that clinical decisions should be founded on multiple separate judgments about the potential recipient cat, the potential source cat and other associated cats. In my view, kidney transplantation should not occur where any one cat would be harmed overall. This rules out, firstly, cases where transplantation would cause more suffering to the recipient than euthanasia (i.e. ‘overtreatment’; Yeates, 2010b, 2013); secondly, using any source cats which would be harmed overall and, thirdly, rehoming source cats to adopters other than the recipients’ owners.
J.W. Yeates/The Veterinary Journal 202 (2014) 405–407
Regulators might permit post-mortem harvesting or using shelter cats destined for euthanasia in cases that benefit all stakeholders. However, in addition, they need to consider potential wider, indirect, adverse effects, such as misuse, unfairness and demotivation. Potential misuses include inappropriate patients receiving kidneys, shelter cats losing a kidney despite not being genuine ‘death row’ cases, or adopters who euthanase or neglect a shelter cat after receiving the kidney for their own animal. It may be difficult for shelter staff and veterinary surgeons to differentiate genuine cases from misuses. As an example, where a decision depends on whether the recipient cat’s owner would or would not otherwise adopt a shelter cat, this question may not be (1) appropriate for shelter staff to ask without causing offence or (2) answered honestly by the owner. Regulators should therefore mandate appropriate safeguards (e.g. clinical ethics committees, owner consent and professional veterinary ethics), although these may still be insufficient. Potential ‘unfairness’ comes from a society doubly disadvantaging shelter cats by not only relinquishing them, but then removing a kidney to benefit already well-kept recipients. This is similar to concerns about the ethics of allowing impoverished humans to ‘trade’ their kidneys, even if both parties benefit from the transaction in isolation. Another potential unfairness is providing transplants for owners who would not adopt a cat otherwise, but not to altruistic owners who would give another cat a loving home unconditionally. Demotivation may reduce efforts to prevent kidney problems caused (or at least predisposed) by irresponsible breeding practices. Breeders may be less motivated to health-test and select breeding stock that do not carry the genes and buyers may be less motivated to exert any consumer pressure, since offspring can be kept alive and breeding through kidney transplantations anyway. This may be of considerable concern with regard to efforts to decrease the prevalence of polycystic kidney disease in certain breeds of cats. These considerations might lead us to the state where we wish to exclude the use of shelter cats, even if this involves prohibiting beneficial cases. Conclusions Slightly different prescriptives exist for clinicians and regulators in dealing with renal transplantation in cats. Regulations should prohibit kidney transplantations, in order to prevent misuse or reduced motivation for other efforts. However, if transplantation is permitted, clinicians might sometimes beneficially take kidneys from shelter cats. As a wider point, it is essential that efforts must continue to improve overpopulation and pedigree breeding. There is no excuse for neglect, abandonment and over-breeding in the first place. Veterinary surgeons, owners and regulators all have a moral obligation to improve adoption rates and decrease shelter euthanasia by other means, such as subsidised neutering and by responsibly promoting adoption. Conflict of interest statement The author is employed by the RSPCA and was a member of British Veterinary Association Council and British Small Animal Veterinary Association Scientific Committee. Acknowledgements The author thanks the audience and fellow participants in a panel discussion at the Congress of the European College of Veterinary
407
Internal Medicine – Companion Animals, Liverpool, UK, 12–14 September 2013, and delegates on the Birmingham Ethics module of the Cambridge Animal Welfare Science, Ethics and Law course, Cambridge, UK, 16–18 September 2013, for useful discussions, and David Morton, Andrew Higgins, Christopher Laurence and Andrew Sparks’ for helpful comments on the paper.
References Adin, C.A., 2002. Screening criteria for feline renal transplant recipients and donors. Clinical Techniques in Small Animal Practice 17, 184. Adin, C.A., Gregory, C.R., Kyles, A.E., Cowgill, L., 2001. Diagnostic predictors of complications and survival after renal transplantation in cats. Veterinary Surgery 30, 515–521. Aronson, L.R., 2002. Retroperitoneal fibrosis in four cats following renal transplantation. Journal of the American Veterinary Medical Association 221, 984–989. Bernsteen, L., Gregory, C.R., Aronson, L.R., Lirtzman, R.A., Brummer, D.G., 1999. Acute toxoplasmosis following renal transplantation in three cats and a dog. Journal of the American Veterinary Medical Association 215, 1123–1126. Bernsteen, L., Gregory, C.R., Kyles, A.E., Wooldridge, J.D., Valverde, C.R., 2000. Renal transplantation in cats. Clinical Techniques in Small Animal Practice 15, 40–45. Case, J.B., Kyles, A.E., Nelson, R.W., Aronson, L., Kass, P.H., Klose, T.C., Bailiff, N.L., Gregory, C.R., 2007. Incidence of and risk factors for diabetes mellitus in cats that have undergone renal transplantation: 187 cases (1986-2005). Journal of the American Veterinary Medical Association 230, 880–884. Chapman, J., 2014. Just How Much Do You Love Your Cat? http://www .dailymail.co.uk/news/article-169382/Just-love-cat.html (accessed 15 August 2014). Gregory, C., 1993. Renal transplantation in cats. Compendium on Continuing Education for the Practicing Veterinarian 15, 1325–1338. Gregory, C.R., 2007. Incidence of and risk factors for diabetes mellitus in cats that have undergone renal transplantation: 187 cases (1986–2005). Journal of the American Veterinary Medical Association 230, 880–884. Gregory, C.R., Mathews, K.G., Aronson, L.R., Ilkiw, J.E., LeCouteur, R.A., Aldrich, J., 1997. Central nervous system disorders after renal transplantation in cats. Veterinary Surgery 26, 386–392. Kyles, A.E., Gregory, C.R., Wooldridge, J.D., Mathews, K.G., Aronson, L.R., Bernsteen, L., Ilkiw, J.E., 1999. Management of hypertension controls postoperative neurologic disorders after renal transplantation in cats. Veterinary Surgery 28, 436–441. Lirtzman, R.A., Gregory, C.R., 1995. Long-term renal and hematological effects of uninephrectomy in healthy feline kidney sources. Journal of the American Veterinary Medical Association 207, 1044–1047. Mathews, K.G., Gregory, C.R., 1997. Renal transplants in cats: 66 cases (1987–1996). Journal of the American Veterinary Medical Association 211, 1432–1436. Mishina, M., Watanabe, T., Maeda, H., Fujii, K., Wakao, Y., Takahashi, M., Ejima, H., 1996. Renal transplantation in cats with chronic renal failure. The Journal of Veterinary Medical Science / the Japanese Society of Veterinary Science 58, 655–658. Pressler, B.M., 2010. Transplantation in small animals. The Veterinary Clinics of North America. Small Animal Practice 40, 495–505. Rollin, B.E., 1981. Animal Rights and Human Morality. Prometheus Books, Buffalo, New York, USA, p. 40. Roudebush, P., Polzin, D.J., Ross, S.J., Towell, T.L., Adams, L.G., Forrester, S.D., 2009. Therapies for feline chronic kidney disease: What is the evidence? Journal of Feline Medicine and Surgery 11, 195–210. Schmiedt, C.W., Holzman, G., Schwarz, T., McAnulty, J.F., 2008. Survival, complications and analysis of risk factors after renal transplantation in cats. Veterinary Surgery 37, 683–695. Wooldridge, J.D., Gregory, C.R., Mathews, K.G., Aronson, L.R., Kyles, A.E., 2002. The prevalence of malignant neoplasia in feline renal transplant recipients. Veterinary Surgery 31, 94–97. Wormser, C., Phillips, H., Aronson, L.R., 2013. Retroperitoneal fibrosis in feline renal transplant recipients: 29 cases (1998–2011). Journal of the American Veterinary Medical Association 243, 1580–1585. Yeates, J., 2009. Response and responsibility: An analysis of veterinary ethical conflicts. The Veterinary Journal 182, 3–6. Yeates, J., 2010a. Death is a welfare issue. Journal of Agricultural and Environmental Ethics 23, 229–240. Yeates, J., 2013. Animal Welfare in Veterinary Practice. UFAW/Wiley-Blackwell, Oxford, UK, p. 92. Yeates, J.W., 2010b. When to euthanase. The Veterinary Record 166, 370–371. Yeates, J.W., 2012. Maximising canine welfare in veterinary practice and research: A review. The Veterinary Journal 192, 272–278.
Contents lists available at ScienceDirect
The Veterinary Journal j o u r n a l h o m e p a g e : w w w. e l s e v i e r. c o m / l o c a t e / t v j l
Personal View
Ethical considerations in feline renal transplantation ☆ James W. Yeates * RSPCA, Wilberforce Way, Southwater, Horsham, West Sussex RH13 9RS, United Kingdom
A R T I C L E
I N F O
Article history: Accepted 8 October 2014 Keywords: Feline Renal Kidney Transplantation Ethics Surgery Veterinary
Introduction Chronic kidney disease (CKD) is very common in cats, especially in cats over 7 years of age. It can be caused by many conditions, including tumours, infections and polycystic kidney disease; the latter being particularly common in Persian cats. One treatment option that is available in some countres is feline renal transplantation, which involves the implantation of a kidney from a ‘source’ cat into a ‘recipient’ cat. Cats can tolerate transplantation from unrelated animals of the same species, using immunosuppressive drugs, such as cyclosporine, to reduce rejection risks. Affected cats are assessed for suitability, stabilised on fluid therapy and treated for hypertension (Bernsteen et al., 2000; Adin, 2002; Pressler, 2010). Potential source cats must also be assessed for suitability (they are usually young, healthy cats), and they are then anaesthetised and have a single kidney removed. The transplant is implanted in the recipient cat through vascular surgery under anaesthesia, with the original kidneys usually left in place. The kidney may be obtained from shelter cats destined for rehoming. Other sources, including recently deceased cats, purposebred cats and biotechnical solutions (such as cloning) are not discussed here. Feline kidney transplantations have been performed since the 1980s for cats with CKD (Gregory, 1993; Mishina et al., 1996;
☆ Please note that the content in this Personal View article has not been subject to peer-review. The views expressed in this Personal View are entirely those of the author and do not necessarily reflect those of the editorial team, or Elsevier. * Tel.: +44 3001230129. E-mail address: [email protected].
http://dx.doi.org/10.1016/j.tvjl.2014.10.006 1090-0233/© 2014 Published by Elsevier Ltd.
Mathews and Gregory, 1997). Nevertheless, it remains a controversial treatment option and views on its acceptability differ among clinicians and countries. For example, transplantation appears to be permissible in Australia, New Zealand and the USA under particular conditions1. In the UK, the procedure was permitted in 20032, but in 2013 authority was suspended pending a review3. Also in the UK, the Royal Society for the Prevention of Cruelty to Animals (RSPCA) considers that the practice may be illegal as it causes unnecessary suffering (Chapman, 2014). Veterinary surgeons and rescue centres therefore face difficult decisions regarding the procedure and in judging whether to perform transplantation to and from identified cats in specific cases. Currently, kidney transplantation is relatively rarely performed in cats. However, because kidney disease is so prevalent, it is likely that the procedure may become more frequent and it is with this possibility in mind that the present article has been written. There are two main concerns. The first is the harm/benefit in terms of suffering and lifespan, which may be affected by medical diseases, treatment and kennelling (Yeates, 2012, 2013). Both are important elements of veterinary work, although the value of the
1 New Zealand Veterinary Association Guidelines, 2010. http://www.nzva.org.nz/ sites/default/files/policies/9i%20-%20Renal%20Transplantation%20-%20Mar10.pdf (accessed 15 August 2014). Feline CRF Information centre, 2013. Feline Kidney Transplant Facilities. http://www.felinecrf.com/transb.htm (accessed 29 August 2014). 2 RCVS, 2003. Guidelines Approved for Kidney Transplantation in Cats. https:// www.rcvs.org.uk/news-and-events/news/guidelines-approved-for-kidneytransplantation-in-cats/ (accessed 15 August 2014). 3 RCVS, 2013. Miscellaneous. https://www.rcvs.org.uk/advice-and-guidance/codeof-professional-conduct-for-veterinary-surgeons/supporting-guidance/ miscellaneous/ (accessed 15 August 2014).
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J.W. Yeates/The Veterinary Journal 202 (2014) 405–407
latter assumes that the former has been achieved, i.e. a longer life is valuable only if the cat will have a good quality of life (Yeates, 2010a). The second concern we might call ‘cat-likeness’, analogous to concepts such as ‘telos’ (Rollin, 1981), referring to the degree to which a cat meets its species identity; anything that makes it less like a (normal) cat reduces its ‘cat-likeness’. This concept can relate to morphology (e.g. number of body parts) or to function (e.g. biological processes). Recipient cats CKD tends to be progressive, incurable and potentially fatal. The main problem in affected cats is the reduced ability of the kidney to remove toxins from the blood and to adequately concentrate the urine. This may be associated with adverse effects on the wellbeing of cats related to the pathology (e.g. nausea, thirst and malaise) or arising from the medical treatment (e.g. from hospitalisation and transportation), and with a shortened life expectancy, given that it is a terminal condition which usually presents clinically at a late stage (stages 3 or 4). Treatment usually involves supportive care and dealing with any clinical signs; it includes dietary change, use of phosphate binders, medical blood vessel dilatation, and treatment of dehydration, high blood pressure, anaemia and vomiting. Euthanasia may be required in advanced cases. In cats, kidney implantation can reduce the distress of CKD (Schmiedt et al., 2008). However, it can also lead to post-operative pain and there is a risk of complications, such as transplant rejection, infections (Bernsteen et al., 1999), retroperitoneal fibrosis (Aronson, 2002; Wormser et al., 2013), hypertension (Kyles et al., 1999), neoplasia (Wooldridge et al., 2002) and diabetes mellitus (Gregory et al., 1997; Case et al., 2007; Gregory, 2007). Kidney implantation may shorten a cat’s life through peri-operative mortality (Adin et al., 2001) or may extend a cat’s life, perhaps for several years (Schmiedt et al., 2008). The veterinarian therefore must gamble between relatively predictable deterioration and short-term effects on the well-being of the animal, followed by a longer life in better health of unknown duration. This gamble is especially difficult because it relies on limited scientific information (Roudebush et al., 2009). There will also be different odds for different cats, as recipients may be affected by kidney disease or by a particular medical treatment in different ways. For example, some animals may have other concurrent diseases that would cause clinical signs or shorten life anyway. Perhaps most importantly, the cat’s future quality of life depends on the owner, who needs to be able to cope with the likely progression of CKD versus the costs of treatment, including ongoing immunosuppression and, if they adopt the cat whose kidney is implanted, the demands of keeping a second cat for many years, and on the patient’s tolerance of that cat. Each particular case therefore requires a tailored evaluation. It can be argued that adding an exogenous kidney somehow detracts from the individual animal’s ‘cat-likeness’. Certainly, most cats have two kidneys, whereas kidney recipients generally finish with three. Furthermore, the additional kidney may be thought to enhance the cat’s overall function above that of normal cats. However, I find this argument less convincing than it immediately appears. Firstly, the implantation of an additional kidney can be thought of as merely a substitution by a replacement kidney (even if the original kidneys are left in situ); this would be analogous to treatments such as insulin for diabetes. Secondly, if we consider that the decreased function of the original kidneys is due to abnormal pathology or problems from cat breeding, then the new kidney is simply maintaining normal function. In neither case is the cat necessarily better than normal. Theoretically, it might be possible to perpetuate a cat’s lifespan or increase its function well beyond normal, but such cats would constitute categorically different cases.
Potential source cats It can also be argued that a source cat is made less ‘cat-like’ by ‘mutilations’ that remove a body part, in this case a kidney. However, this argument also has limited force. The value of a body-part seems to depend on its function (consider human appendices); it seems hard to defend the view that lacking non-functional anatomy is intrinsically bad. Losing one kidney may not have any major effect on kidney function, since most cats have ‘spare capacity’ that allows overall renal function to be unaffected by having a single kidney. Only if pathological or degenerative changes reduce the functional capacity of the remaining kidney below its spare capacity, will the absence of a second kidney then reduce overall renal function. In a small scale evaluation of the long term (24–67 months) effects of unilateral nephrectomy in 16 healthy source cats, one cat was diagnosed with chronic renal insufficiency at 52 months postsurgery (Lirtzman and Gregory, 1995). Given the prevalence of CKD, this risk does not appear to make source cats ‘less cat-like’. Rather, the functional significance of this change is best assessed by considering its clinical effects. In actuality, the removal of a kidney is likely to cause some adverse effects on well-being. Pre-surgical testing and preparation may involve moderately unpleasant experiences of transportation, hospitalisation, handling, venepuncture and sedation. Surgical complications may result in more substantial acute suffering. Any later kidney disease may worsen more quickly. These risks mean that, in general, and all other things being equal, nephrectomy can be expected to reduce the mean (but not necessarily median) well-being and life expectancy. Again there is a gamble, the value of which depends on what would otherwise happen to the source cat. In particular, would it suffer and die for some other reason? Of particular importance here is whether the animal would undergo long term kennelling or euthanasia in a shelter. Several shelters in the USA run schemes in which owners of cats with renal disease can adopt a shelter cat, which provides a kidney to their prior cat and which itself is rehomed to an owner who cannot get the kidney without rehoming the donor cat. The cat thereby gets rehomed, albeit at the cost of a kidney, and saved from euthanasia. Of course, the transaction is not beneficial if the owner then unscrupulously euthanases or neglects the adopted cat, or if the source cat were to be rehomed anyway, either to another adopter (as many young, healthy cats are often popular with adopters) or to the owner of the potential recipient (if they could adopt that cat anyway). However, rehoming one cat may affect the rehoming of other cats, where charities are faced with more animals requiring their care than there are adopters willing to rehome. On the plus side, rehoming a source cat that would have been rehomed anyway ‘frees up’ an adopter to adopt another cat. On the minus side, if the source cat is adopted by someone who would otherwise have adopted another cat, then the source cat ‘uses up’ that adopter, perhaps indirectly leading to the euthanasia of another cat, with no net benefit.
Implications for kidney transplantation decision-making Each veterinary surgeon has a duty not to harm a patient unnecessarily, even for the benefit of another animal (Yeates, 2009). This means that clinical decisions should be founded on multiple separate judgments about the potential recipient cat, the potential source cat and other associated cats. In my view, kidney transplantation should not occur where any one cat would be harmed overall. This rules out, firstly, cases where transplantation would cause more suffering to the recipient than euthanasia (i.e. ‘overtreatment’; Yeates, 2010b, 2013); secondly, using any source cats which would be harmed overall and, thirdly, rehoming source cats to adopters other than the recipients’ owners.
J.W. Yeates/The Veterinary Journal 202 (2014) 405–407
Regulators might permit post-mortem harvesting or using shelter cats destined for euthanasia in cases that benefit all stakeholders. However, in addition, they need to consider potential wider, indirect, adverse effects, such as misuse, unfairness and demotivation. Potential misuses include inappropriate patients receiving kidneys, shelter cats losing a kidney despite not being genuine ‘death row’ cases, or adopters who euthanase or neglect a shelter cat after receiving the kidney for their own animal. It may be difficult for shelter staff and veterinary surgeons to differentiate genuine cases from misuses. As an example, where a decision depends on whether the recipient cat’s owner would or would not otherwise adopt a shelter cat, this question may not be (1) appropriate for shelter staff to ask without causing offence or (2) answered honestly by the owner. Regulators should therefore mandate appropriate safeguards (e.g. clinical ethics committees, owner consent and professional veterinary ethics), although these may still be insufficient. Potential ‘unfairness’ comes from a society doubly disadvantaging shelter cats by not only relinquishing them, but then removing a kidney to benefit already well-kept recipients. This is similar to concerns about the ethics of allowing impoverished humans to ‘trade’ their kidneys, even if both parties benefit from the transaction in isolation. Another potential unfairness is providing transplants for owners who would not adopt a cat otherwise, but not to altruistic owners who would give another cat a loving home unconditionally. Demotivation may reduce efforts to prevent kidney problems caused (or at least predisposed) by irresponsible breeding practices. Breeders may be less motivated to health-test and select breeding stock that do not carry the genes and buyers may be less motivated to exert any consumer pressure, since offspring can be kept alive and breeding through kidney transplantations anyway. This may be of considerable concern with regard to efforts to decrease the prevalence of polycystic kidney disease in certain breeds of cats. These considerations might lead us to the state where we wish to exclude the use of shelter cats, even if this involves prohibiting beneficial cases. Conclusions Slightly different prescriptives exist for clinicians and regulators in dealing with renal transplantation in cats. Regulations should prohibit kidney transplantations, in order to prevent misuse or reduced motivation for other efforts. However, if transplantation is permitted, clinicians might sometimes beneficially take kidneys from shelter cats. As a wider point, it is essential that efforts must continue to improve overpopulation and pedigree breeding. There is no excuse for neglect, abandonment and over-breeding in the first place. Veterinary surgeons, owners and regulators all have a moral obligation to improve adoption rates and decrease shelter euthanasia by other means, such as subsidised neutering and by responsibly promoting adoption. Conflict of interest statement The author is employed by the RSPCA and was a member of British Veterinary Association Council and British Small Animal Veterinary Association Scientific Committee. Acknowledgements The author thanks the audience and fellow participants in a panel discussion at the Congress of the European College of Veterinary
407
Internal Medicine – Companion Animals, Liverpool, UK, 12–14 September 2013, and delegates on the Birmingham Ethics module of the Cambridge Animal Welfare Science, Ethics and Law course, Cambridge, UK, 16–18 September 2013, for useful discussions, and David Morton, Andrew Higgins, Christopher Laurence and Andrew Sparks’ for helpful comments on the paper.
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