Fludrocortisone—a treatment for tubulopathy post‐paediatric renal transplantation: A national paediatric nephrology unit experience

Abstract

Calcineurin inhibitors post-renal transplantation are recognized to cause tubulopathies in the form of hyponatremia, hyperkalemia, and acidosis. Sodium supplementation may be required, increasing medication burden and potentially resulting in poor compliance. Fludrocortisone has been beneficial in addressing tubulopathies in adult studies, with limited paediatric data available. A retrospective review of data from an electronic renal database from December 2014 to January 2016 was carried out. Forty-seven post-transplant patients were reviewed with 23 (49%) patients on sodium chloride or bicarbonate. Nine patients, aged 8.3 years (range 4.9-16.4), commenced fludrocortisone 22 months (range 1-80) after transplant and were followed up for 9 months (range 2-20). All patients stopped sodium bicarbonate; all had a reduction or no increase in total daily doses of sodium chloride. Potassium levels were significantly lower on fludrocortisone, 5.2 vs 4.5 mmol/L, P = .04. No difference was noted in renal function (eGFR 77.8 vs 81.7 mL/min/1.73 m , P = .45) and no significant increase in systolic blood pressure (z-scores 0.99 vs 0.85, P = .92). No side effects secondary to treatment with fludrocortisone were reported. A significant proportion of renal transplant patients were on sodium supplementation and fludrocortisone reduced sodium supplementation without significant effects on renal function or blood pressure. Fludrocortisone appears to be safe and effective for tubulopathies in children post-transplantation.

Hyperchloremic metabolic acidosis in the kidney transplant patient

“…Besides, it has been suggested that potassium citrate could be superior to sodium bicarbonate, because it lacks volume effects and obligatory calcium excretion associated with sodium (36). It has been documented that bone surface, connectivity density, cortical thickness, and cortical porosity are better preserved with potassium citrate than with potassium chloride (36)(37)(38).…”

“…For instance, when a reversible RTA inducing mechanism is detected, one should try to remove the cause, as is the case of a drug-induced RTA or hyperkalemia-induced RTA by withdrawing or adjusting the drug dose or normalizing serum potassium levels, respectively (3). With respect to changing HMA inducing drugs, Schulte et al have recently reported that a late conversion from a tacrolimus-based immunosuppression to belatacept was safe, effective and significantly improved renal function and acid-base balance, independently of glomerular filtration rate, in kidney transplant recipients (38).…”

“…With respect to normalizing serum potassium levels, it can be achieved by different strategies, such as low potassium diet, mineralocorticoid (eg: fludrocortisone), cationic exchange, resins, etc. It is worth pointing out that mineralocorticoid should be used with precaution in these patients due to their potent sodium retention effect (14,28,38,39).…”

Calcineurin inhibitor‐associated electrolyte disturbances after pediatric renal transplantation: Could fludrocortisone therapy have a role?

“…In this issue of Pediatric Transplantation , Ali et al report data on national experience of the efficacy of fludrocortisone in the management of post‐renal transplant tubulopathy and its potential benefits for pediatric renal transplant recipients. As pointed out, this approach in dealing with electrolyte disturbances is novel and nearly unexamined.…”

“…5,6 To date, only one study on pediatric fludrocortisone-treated renal recipients has been performed and according to the results, on the one hand, significant reduction in sodium supplementation was achieved but, on the other hand, significant increase in blood pressure levels was observed. 7 In this issue of Pediatric Transplantation, Ali et al 8 or non-compliance. It must be stressed, however, that the referenced study was also small in size and fludrocortisone therapy was stopped in six of the 15 subjects (n = 1 for each of the five reasons mentioned above and one scheduled cessation).…”