Dangers of broth after transplantation

Abstract

Serum creatinine is routinely used to monitor renal function in transplant recipients. External factors including diet, exercise and hydration status can also influence serum creatinine concentration on a day-to-day basis. We describe a case of a patient whose serum creatinine increased from 128 to 171 μmol/L after ingestion of creatinine-rich (3098 μmol/L) soup. A renal biopsy was performed but revealed no cause for the rise in creatinine and by the next day, serum creatinine had returned to baseline. We conducted two experiments to examine the effect of soup ingestion by healthy volunteers. We measured the creatinine concentration of various store-bought stock preparations and found creatinine concentrations less than one-quarter of that contained in our patient's homemade soup. A creatinine-rich soup (4334 μmol/L) was ingested by six healthy volunteers age 33 (± 6.5) years with baseline normal serum creatinine 68 (± 14) μmol/L. Mean (standard deviation) serum creatinine increased to 77 (± 11) μmol/L 4 hours after soup ingestion (P = 0.0015, paired t-test). Mean (standard deviation) creatinine clearance, extrapolated from the 4 hour urine collection following soup ingestion, was high (267 ± 198 mL/min) exhibiting a supra-normal creatinine clearance. The rate of serum creatinine rise was lower in volunteers compared with the transplant patient, consistent with the concept of renal functional reserve. Our case highlights the importance of taking dietary changes into account when interpreting serum creatinine as a measure of allograft function.

Bone broth ingestion and acute kidney injury following kidney transplant: a role for cystatin C

“…Patients with normal renal functional reserve respond to protein loads by increasing their creatinine clearance and GFR 1. When six healthy volunteers were given a meat broth (creatinine 4334 µmol/L), and creatinine clearance was measured 4 hours later, it was supraphysiological, with a mean of 267±198 mL/min 8. The same phenomenon occurred in donors and recipients when GFR was measured by radionucleotide scintigraphy 9.…”

Haemodynamic or metabolic stimulation tests to reveal the renal functional response: requiem or revival?

“…Red meat, however, contains 3.5–5 mg/g creatine. By cooking, a non-metabolic conversion of creatine to creatinine occurs [ 53 ]. This metabolite is easily absorbed and the rising serum levels result in increased tubular secretion until the tubular transport maximum is reached [ 54 ].…”

Introduction

“…We are delighted to sponsor the publication of the top six cases, as chosen by the Panel, to be published in no particular order in this supplement of Nephrology . A seventh case report entitled The dangers of broth after transplantation was also selected by the panel, and this will appear separately in an upcoming issue of the journal.…”