Recognizing Chronic Kidney Disease in Children

Goals Know the epidemiology of kidney disease in children Identify chronic kidney disease when you see it Know how to screen for kidney disease

“Real Goals” Add “renal disease” to your differential for 5 common pediatric complaints Be able to name the #1 cause of pediatric end-stage renal disease Name 1 way to stop progression of kidney disease Use the Schwartz Formula to calculate GFR every time you see a creatinine

Glomerular Filtration Rate (GFR): How much plasma is filtered per minute Normalized to body surface area (1.73 m2) Reaches BSA-corrected adult levels by 2 months of age

Normal GFR 100 mL/min/1.73m2

How much kidney do you need to lose before your creatinine increases?

What’s an abnormal creatinine?

Who’s Got an Abnormal Creatinine ? VS. 10 mo/o boy Cr = 0.6 16 y/o boy Cr = 1.0

VS. Who’s Got an Abnormal Creatinine ? 4 y/o boy 15 y/o girl Cr = 0.8

= K * height (cm) ------------------- GFR Creatinine (ml/min/1.73m2) The Schwartz Formula K * height (cm) ------------------- Creatinine GFR (ml/min/1.73m2) = Babies Kids Teenage Girl Teenage Boy K 0.45 0.55 0.7 Schwartz, 1976.

53 = K * ht 0.45 * 70 -------- ------------- Cr 0.6 (ml/min/1.73m2) 10 month old boy Length = 70 cm Cr = 0.6 K * ht -------- Cr = 0.45 * 70 ------------- 0.6 53 (ml/min/1.73m2)

126 = K * ht 0.70 * 180 -------- ------------- Cr 1.0 (ml/min/1.73m2) 16 year old boy Ht = 180 cm Cr = 1.0 K * ht -------- Cr = 0.70 * 180 ------------- 1.0 126 (ml/min/1.73m2)

73 = K * ht 0.55 * 107 -------- ------------- Cr 0.8 (ml/min/1.73m2) 4 year old boy Ht = 107 cm Cr = 0.8 K * ht -------- Cr = 0.55 * 107 ------------- 0.8 73 (ml/min/1.73m2)

91 = K * ht 0.55 * 150 -------- ------------- Cr 0.9 (ml/min/1.73m2) 15 year old girl Ht = 150 cm Cr = 0.9 K * ht -------- Cr = 0.55 * 150 ------------- 0.9 91 (ml/min/1.73m2)

Other Ways to Measure GFR Timed Urine Collection Nuclear Medicine Scan Cystatin C

How accurate do you need to be?

Stages of Chronic Kidney Disease CKD Stage Severity GFR ml/min/1.73m2 1 Minimal >90 + evidence of damage 2 Mild 60-89 3 Moderate 30-59 4 Severe 15-29 5 Kidney failure <15 Pause – what are the functions of the kidney? Lytes, fluids, bp control, toxin(uremia buildup), acid/base, epo, vit D

Clinical Manifestations of Kidney Disease and Stage

U.S. Adult Population with Kidney Disease Stage 5 4 3 2 1 300k 400,000 8,000,000 12,000,000 25 million

U.S. Pediatric Population with Kidney Disease Stage 5 4 3 2 1 5000 Estimate 400,000 GFR < 80 (NHANES III)

When did he start getting kidney disease?

Internists are seeing what we’re not.. Trans- plant PD HD

Top 5 Causes of Pediatric Kidney Disease Top 2 comprise 70+%

Seven Red Flags for Kidney Disease Failure to Thrive

Seven Red Flags for Kidney Disease Failure to Thrive Elevated Blood Pressure

Seven Red Flags for Kidney Disease Failure to Thrive Elevated Blood Pressure Chronic Anemia

Seven Red Flags for Kidney Disease Failure to Thrive Elevated Blood Pressure Chronic Anemia Voiding Problems

Seven Red Flags for Kidney Disease Failure to Thrive Elevated Blood Pressure Chronic Anemia Voiding Problems Unusual Bone Disease

Seven Red Flags for Kidney Disease Failure to Thrive Elevated Blood Pressure Chronic Anemia Voiding Problems Unusual Bone Disease Proteinuria

Seven Red Flags for Kidney Disease Failure to Thrive Elevated Blood Pressure Chronic Anemia Voiding Problems Unusual Bone Disease Proteinuria Pre-Existing Diseases

Why bother identifying kidney disease in kids?

Slow Progression… HTN, proteinuria, BMI, high uric acid, smoking (not etoh), avoiding nephrotoxins, avoiding dehydration, ApoE, lipids, ?birth weight/preemie, ?homocystine,

ACE Inhibitors slow Progression of Renal Disease REIN 1993

Improve Quality of Life… School attendance, hospitalization, teasing

Percentage of Children starting renal replacement therapy before 15 years of age who are < 2 SD below mean adult height Rizzoni, 1985 Hokken-Koelega, 1994

Adults at -2 SD for Height 5’ 5” 4’ 11” 60-77 % of boys end up shorter than Woody Allen 40-71 % of girls end up shorter than Lil’ Kim

Anticipate and Treat Complications…

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