What Not to Eat After Nephrectomy
In the past, nephrectomy, either for kidney donation or cancer, did not appear to be associated with a higher risk of chronic kidney disease (CKD) and end-stage renal disease (ESRD). The more recent literature, however, has been relatively consistent in suggesting that both donor and cancer nephrectomy are associated with a several-fold higher risk. For example, a study by Abimereki D. Muzaale, MD, MPH, of Johns Hopkins University in Baltimore, found that the risk of ESRD at 15 years after donation was 30.8 per 10,000 among kidney donors compared with 3.9 per 10,000 in a group of matched healthy non-donor counterparts.1 And, based on a meta-analysis, Morgan E. Grams, MD, also of Johns Hopkins, and colleagues found that the 15-year observed risks for ESRD were 3.5 to 5.3 times as high as the projected risks in the absence of donation.2
Not infrequently, both urologists and nephrologists provide follow-up and continuity of care to patients after cancer nephrectomy. Patients invariably ask us what to eat to protect the remaining kidney. We deal with the same question from kidney donors. In the past, doctors may have reassured kidney donors that they are not at higher risk of ESRD. Today, it would be naïve for physicians to believe that patients with a solitary kidney after nephrectomy do not have a serious condition and do not need dietary advice or diet and lifestyle modification. In fact, many contemporary patients who undergo donor or cancer nephrectomy demand nutritional advice.
No controlled clinical trial, however, has examined whether dietary approaches, such as a low-protein and low-salt diet, are effective in mitigating the higher risk of CKD and ESRD, but there are extensive data suggesting that higher protein intake is associated with glomerular hyperfiltration and higher risk of CKD.3
At my institution, we invariably suggest slightly lowered dietary protein intake of 0.8-1.0 g/kg per day combined with moderately low sodium diet of less than 4 grams per day. This slight dietary modification is pragmatic, as many of our patients do follow these recommendations. We strongly hope that additional studies are inspired and supported based on this and other discussions and publications. A challenge remains with athletes such as bodybuilders and weight lifters with a solitary kidney, who often look at me as the crazy, disconnected, non-athletic doctor when I tell them to lower protein intake.