At the beginning of each term I chat with our new residents and fellows to find out what excites them about paediatric nephrology, aiming to tailor their project and exposure to their interests. Many of our junior team are planning to do general paediatrics (inevitably part-time, in the country, with a special interest in neonatology) and the fellows express a fascination with transplant, haemodialysis, or genetics. What they are never interested in though, is chronic kidney disease (CKD).
The management of CKD is an exercise in simplicity and tedium, following the same straightforward checklist for each patient. There are no accolades for good CKD management. No thanks. No awards. If managed well then their GFR declines at a slower rate and they feel better. But, hey, we’re paediatric nephrologists, right? We don’t need thanks, we just want our patients to grow up big and strong, and we don’t ever want them to feel sick.
After reading The Checklist Manifesto I became even more convinced that the consistent application of lists could improve patient care, particularly in this neglected area of paediatric nephrology. With this in mind I created a checklist which has migrated to a smartphrase in my hospital EMR, to make sure I optimise medical management of CKD for every patient, every time.
Iron – Check Hb and Iron studies. Kidney tissue needs oxygen to work effectively. The prevention of anaemia decreases CKD progression, decreases LVH, decreases sensitizing transfusions and increases quality of life. Supplement with oral iron early on and consider IV as necessary. Consider erythropoietin stimulating agents in stage 4 CKD when the kidney produces less erythropoetin.
Vitamin D – Most kids have low levels of 25-hydroxyvitamin D and I aim to keep levels >75nmol/L. Post hoc analysis of the ESCAPE trial showed 5-year renal survival was 75% in patients with baseline 25-hydroxyvitamin D ≥50 nmol/L and 50% in those with lower 25-hydroxyvitamin D levels (P<0.001). Vitamin D may promote renal protection by suppressing renin transcription through crosstalk between the renin-angiotensin-aldosterone and vitamin-FGF23-Klotho pathways. Supplement with an age appropriate dose (most get 1000 IU/day) and consider stress dosing with caution (e.g. 100,000 IU) in clinic to get the levels up and use regular dosing for maintenance.
Phosphate – Aim to keep levels around the 50th percentile for age, remembering that levels are lowest in the morning so hovering above the normal range at that stage is not good news. Remember that vascular calcification starts in early CKD and is a major cause of morbidity and mortality for our patients in adulthood. Don’t wait until the chemistry is abnormal, talk to families about limiting phosphate containing foods in early CKD, refer to your renal dietician, and consider phosphate binders if levels are sneaking up despite good dietary control. Considering a vegetarian diet is also a sensible move perhaps because non-animal phosphate appears to be less avidly absorbed.
PTH – Aim to keep this in the normal range. Around CKD stage 3 the kidneys are less efficient at converting 25-hydroxyvitamin D to the active 1,25-dihydroxyvitamin D, so give the smallest supplement you can to maintain normal PTH and calcium levels.
Blood Pressure – Normal blood pressure reduces glomerular pressure and long standing damage. Initial non-pharmacological measures such as weight reduction, exercise and salt restriction are good for the kidneys on many levels. But if hypertension persists then controlling BP to the 50th percentile (if tolerated) is the goal, since the ESCAPE trial showed a significant reduction in GFR decline in those controlled to the 50th percentile. Following the comprehensive AAP guidelines is your best bet and I tend to choose and ACE inhibitor if proteinuria is also present.
Proteinuria – Controlling proteinuria should reduce damage to the glomerulus. An increase of creatinine of 20% with the use of an ACE inhibitor is acceptable if the proteinuria is controlled. Warn parents in advance about this and remember to discuss the potential for teratogenicity in post-pubertal girls using an ACE inhibitor.
Acid-Base – Aim to maintain bicarbonate levels above 22 mEq/L with oral supplementation to prevent bone buffering, growth failure and progression of CKD.
Fluid Management – In early CKD many of our patients (particularly those with obstructive uropathy or nephronophthisis) can have a relative urinary concentrating defect. This results in polyuria and polydipsia which often isn’t noticed unless we ask about heavy diapers, frequent urination, bedwetting and increased thirst in the morning. Generally this can be easily managed by parents allowing free access to water but it’s worth discussing why a child might be grumpy and thirsty in the morning and the importance of seeking early medical attention for a vomiting illness to prevent AKI.
The above list applies to my patients in early CKD, and represents my opinion and clinical practice. I’d be delighted to hear from readers of this blog as to their views, biases and approaches to the management of patients in early CKD.