Chronic Kidney Disease (CKD) Mignon McCulloch Associate Professor Paediatric Nephrology/Critical Care Red Cross Children s Hospital (RXH) University of Cape Town
Chronic Renal Failure(CRF) = Chronic Kidney Disease No incidence figures in Africa Europe: approx 3 million children per year who can benefit from treatment GFR ml/mil/1.73m 2 (Normal = 80-120) Mild CRF <50 Moderate CRF <30 Severe <10 Now replaced by KDIGO 2017
CURRENT CHRONIC KIDNEY DISEASE (CKD) NOMENCLATURE USED BY KDIGO 2017 CKD is defined as abnormalities of kidney structure or function, present for > 3 months, with implications for health. CKD is classified based on cause, GFR category (G1 G5), and Albuminuria category (A1 A3), abbreviated as CGA.
Dillon 2 year old boy Looks fine, just a bit small and crooked but active and runs around Wt 10kg(<3 rd C) Ht 75cm(3 rd C) BP 130/70 Deformed legs, wide wrists, prominent forehead Nothing much else to find Xray: Severe ricketts
Blood Results Hb 7 MCV 85 WC 5 Plt 200 Na 130 K 5.0 U 18 Cr 200 Ca 2.1 Po4 2.2 ALP 180 PTH 30(1-6) Ven gas ph 7.25 Be 15 Bic 12
Useful Formulaes Schwartz GFR(ml/mil/1.73m 2 ) Ht X 38 = 75 X 38 = 14 Creatinine 200 Systolic BP (Age in yrs X 3) + 100 = 95 th Centile New 2017 AAP Hypertension Guidelines Flynn et al, Pediatrics 2017; 140:e20171904
2017 AAP Guidelines for Childhood Hypertension: What the Clinician Needs to Know Joseph T. Flynn, MD, MS, FAAP Professor of Pediatrics, University of Washington Chief, Division of Nephrology, Seattle Children s Hospital Flynn et al, Pediatrics 2017; 140:e20171904
Major Changes From the Fourth Report Rigorous evidence-based methodology Revised definitions of blood pressure categories; alignment with AHA/ACC GL New normative BP tables based on BPs from normal-weight children Simplified screening table
Major Changes From the Fourth Report Emphasis on use of 24-hr ABPM to confirm HTN diagnosis Revised recommendations for performance of echocardiography Lower treatment goals for primary HTN; ABPM goal for CKD
Definition of HTN (1-18y) Changes in HTN definition compared to the Fourth Report: BP >90 th percentile now termed elevated BP BP cut-points for stage 1 and 2 HTN simplified BP cut-points for adolescents 13 years old are the same as in new AHA/ACC adult HTN guideline
Definition of HTN in Neonates and Infants (0-1 y) Many factors affect BP in neonates, making it hard to precisely define HTN BP values for neonates 26-44 weeks post-menstrual age have been compiled and may be used to identify neonates with high BP 2 nd TF Report BP curves should still be used for infants 1-12 months of age
New Normative BP Tables 4 th Report BP tables generated from BP values in ~70,000 healthy children Many children had overweight or obesity Inclusion of these children likely biased normative BP values upward New normative BP tables commissioned for this CPG, based only on BP readings from ~50,000 normal-weight children
Flynn et al, Pediatrics 2017; 140:e20171904 New BP Tables
BP Measurement Frequency Unclear what age is optimal to begin routine BP measurement Data suggest that prevention and intervention efforts should begin early New guideline does not change recommendation to begin BP measurement at age 3 Now only annual measurement recommended unless risk factors present
Causes of CKD CAKUT commonly Reflux Nephropathy Obstructive Nephropathy Congenital Dysplasia Glomerulonephritis Rapidly progressive GN post strep Focal Segmental Glomerulosclerosis (FSGS) Congenital Nephrotic
Clinical Features OFTEN VERY FEW SIGNS UNTIL DISEASE IS VERY ADVANCED
Clinical Features - Minor Often non-specific Polyuria Polydipsia Pallor Poor Growth
Clinical Features - major Anaemia Anorexia Bone disease Behaviour Developmental Growth Failure Hyperkalaemia Hyperlipidaemia Hypertension Metablic Acidosis Polyuria
Anaemia Hb 7 MCV 85 Loss of energy, poor appetite, poor school performance Adequate stores of Iron and Folate Initially Rx Elemental iron 2-3mg/kg/day Folate 2.5 5mg/day Later Rx Erythropoietin 100 200u/kg/week subcut once weekly until Hb > 10 Ivi Iron
Anaemia Do NOT blood transfuse if at all possible unless in severe cardiac failure Especially if plan long term to transplant develop antibodies Apart from all inherent dangers of blood transfusion
Anorexia Nutrition very NBB Normal protein diet(unlike Adults) Higher energy 25% above normal Age Energy Protein kcal/kg/day g/kg/day < 1yr 130 2.0 < 3yrs 125 1.8 < 6yrs 100 1.5 < 12yrs 100 1.0 Multivitamins
What you can do to increase intake Concentrate feeds if on fluid restriction Messy play with food and eat with family Medication : prokinetic, antacids, ondansetron Avoid force feeding
Enteral feeding
Nasogastric tube feeding Generally for small babies <4kg Advantages Easily placed and taught No risk of peritonitis Disadvantages GOR vomiting Oromotor skill later speech and swallowing Mark child as sick Frequent replacement Continuous feeds only Naso-jejunal tubes Need to be done by skilled person
Gastrostomy insertion Percutaneous: Endoscopic, Laporoscopic, Radiological Less invasive more chance organ damage Before PD initiation Open After PD initiation prophylactic antibiotic and antifungal therapy Warady BA ISPD guidelines for infections and peritonitis 2012 update. Perit Dial Int LUQ don t put exit site there
Gastrostomies at RXH Day procedure start feeds next day
Peritonitis and GT feeds Increased Hijazi R, J Pediatr 2009 Most no difference NAPRTCS Warady BA. Kidney Int 2000 IPPN PEG after catheter New Zealand 17 children Compared Peritonitis rate before and after laparoscopic GT No difference in peritonitis rate Prestidge Pediatr Nephrol 2015
Key points: enteral feeds KDOQI: advise enteral tube in children not getting adequate nutrition If you wait too long before starting enteral feeds you will have lost an opportunity Gastrostomy not without complications but benefits outweigh negatives Gastrostomy placement preferably before PD initiation Helps even with PEW and older children KDOQI Clinical Practice Guideline for Nutrition in Children with Chronic Kidney Dise 2008 Update. Am J Kidney Dis
PEW Hypercatabolism Inflamation Endocrine dysfunction Poor appetite Nutrition
Growth Failure Wt 10kg(<3 rd C) Ht 75cm(3 rd C) Major problem optimise growth and brain development Poor appetite, increased GOR, poor gastric emptying and uraemic nausea Mealtimes a battlefield Nasogastric tube feeds
Growth Failure Adequate nutrition, Control of metabolic bone disease, Sodium supplements in some Especially post urethral valves & dysplasia Concentrating defect with salt wasting Titrate against BP
Bone Disease Ca 2.1 Po4 2.2 ALP 180 PTH 30(1-6) Reduce Phosphate using binder with food Start with Titralac(Calcium carbonate) Aim for Po4 <1.5 New Ca free PO4 binders(rees L Ped neph 2015) Calcium keep normal for age Add in 1 vitamin D 0.25 g daily
CKD MBD - Biochemical Abn Stage of CKD Ca Po4 PTH G3a/b 30-59 (Kids G2 60-89) 6-12mthly Baseline and then progress G4 3-6mthly 6-12mthly G5-5D 1-3mthly 3-6mthly G4 G5D Alk Phos 12mthly or if incr PTH If on Rx for CKD MBD Incr freqs to monitor trends & efficacy
Bone Disease Children with CKD G2 G5D linear growth at least annually Monitor PTH if possible and aim 1-2 times normal check as per GFR - Alkaline phosphatase not accurate Involve orthopaedic team early MBD testing if risk of osteoporosis Bone biopsies controversial
CKD G3a- 5D 25(OH)D (calcidiol) levels might be measured. Vitamin D deficiency and insufficiency be corrected using treatment strategies recommended for the general population (2C). Therapeutic decisions be based on trends rather than on a single laboratory value Lab informs of changes
Developmental Adequate nutrition Family dynamics disrupted Schooling NB
Hyperkalaemia K = 5.0 Usually late stage acute rise Fruit juices and fruits avoided Kayexalate 0.5mg/kg/dose 1-2 times daily
Hyperlipidaemia Some nephrotic states result in very high cholesterol levels May need lipid lowering agents if chronic
Hypertension Common due to salt and water retention Monitor BP with appropriate cuff Diuretics Loop diuretics in bigger doses Avoid K+ sparing ACE inhibitors especially if proteinuria WATCH K+ Calcium channel blockers B Blockers nightmares!
Metabolic Acidosis KDIGO suggests commencing once serum Bicarb < 22mmol/l Oral Sodium bicarbonate Start with 1-2mmol/kg/day added to feeds in divided doses Adjust until normal range
New Staging System Estimates Time to Kidney Failure in Children April 16, 2018 NEW YORK (Reuters Health) Pediatric nephrologists have developed a staging system to help predict the length of time until a child with chronic kidney disease (CKD) will develop end-stage renal disease (ESRD). The staging system combines three factors estimated glomerular filtration rate (egfr), proteinuria and type of chronic kidney disease (glomerular or nonglomerular etiology) - to estimate how soon children will progress to ESRD.
Am J Kidney Dis 2018, April 10 Combination of GFR, proteinuria, and CKD diagnosis is more informative for assessing risk for disease progression in pediatric patients with CKD than GFR alone Data on more than 1,200 children (median age 12, 60% male) with CKD from the Chronic Kidney Disease in Children (CKid) and ESCAPE (Effect of Strict Blood Pressure Control and ACE Inhibition) studies. Median egfr was 47 ml/min/1.73 m2 and 13% had urine protein-creatinine ratios (UPCR) > 2.0 mg/mg at the outset.
KDIGO classification The team defined ESRD risk categories by egfr stage (60 to 89, 45 to 59, 30 to 44, and 15 to 29 ml/min/1.73 m2) and UPCR (less than 0.5, 0.5 to 2.0, and more than 2.0 mg/mg).
Outcomes Median times to an event renal replacement therapy, 50% reduction in egfr, or egfr less than 15 ml/min/1.73 m2) Ranged from longer than 10 years for egfrs of 45 to 90 ml/min/1.73 m2 and UPCRs less than 0.5 mg/mg to less than one year egfrs of 15 to 30 ml/min/1.73 m2 and UPCRs greater than 2 mg/mg.
Classification system can be used as an adjunct to clinical judgment Children with glomerular disease showed faster progression than those with nonglomerular disease (43% shorter time to event). Development of a clinically useful tool that would help clinicians at the bedside anticipate the timing of needed interventions, such as a pretransplantation evaluation or placement of dialysis access and communicate these to the families of children with CKD
Management Meticulous attention to detail for all parameters Decision about Dialysis and Transplant needs multidisciplinary team That s for another talk