This document discusses CKD-MBD (chronic kidney disease-mineral and bone disorder) and summarizes guidelines and current understanding. It notes that CKD-MBD is a systemic disorder involving abnormalities in calcium, phosphorus, PTH, and vitamin D metabolism as well as bone disease. The focus has shifted from renal rickets to a common, often fatal, silent disorder. High phosphorus levels are associated with cardiovascular risks and CKD progression even in non-CKD patients. Phosphate binders are used to limit dietary phosphorus absorption but can have toxicities. Ongoing research aims to better understand pathophysiology and find new treatment approaches to improve outcomes for patients with CKD-MBD

1. CKD-MBD
05/2015 Dallas Area Dietitians
Jorge Roman-Latorre MD
DNA

2. Following reflects only my personal opinion today
It does not represents DNA or Fresenius
Considers current guidelines
Does not necessarily follow any one protocol
Complex subject : changing fast
We do not have all answers!!!

3. CKD Ca PO4 PTH
 1937 Donahue : CKD Rats had increased Calcium in
kidney tissue, proportional to parathyroid weight.
Parathyroidectomy prevented Ca deposition in
Kidneys
 1978 Ibels : Rats subtotal Nephrectomy on either low
Phosphorus diet or regular chow + Al(OH)3 : Less
uremia , Normal K ; controls had interstitial nephritis,
not controlled for protein intake

4. Man made disease
not noticeable without dialysis
2011 > 2.2M dialysis + .6 M grafted
Rare before chronic dialysis ( 1960 Seattle )
Focus has changed last 35-40 years
From Renal Rickets to a silent common disorder often fatal

5. Foley RN, et al. Am J Kidney Dis. 1998;32:S112-
S119.
GP: General
Population.
0.001
0.01
0.1
1
10
100
25-34 35-44 45-54 55-64 66-74 75-84 >85
GP Male
GP Female
GP Black
GP White
Dialysis Male
Dialysis Female
Dialysis Black
Dialysis White
Age (years)
AnnualCVDMortality(%)

8. Definition of
CKD-Mineral and Bone Disorder
A systemic disorder of mineral and bone
metabolism due to CKD manifested by
either one or a combination of the
following:
 Abnormalities of calcium, phosphorus, PTH,
or vitamin D metabolism
 Abnormalities in bone turnover,
mineralization, volume, linear growth, or
strength
 Vascular or other soft tissue calcification
Moe S, et al. Kidney Int 69: 1945, 2006

9. Excess Mortality (previous slide)
excess Fractures 20% excess Block G.A. CJASN 8:2132-2140 2013
More Kidney Damage = CKD Progression
Renal Osteodystrophy ( a very mixed bag)
Stiff Vessels; Media Calcification; abnormal pulse wave
velocity , abnormal medial thickness
Coronary scores :Calcified heart valves
Excess Atrial Arrythmias?
Lungs, soft tissue calcification; pruritus
Sexual Dysfunction
CVA’s?

10. Pathophysiology of CKD-MBD
PO4
Skeletal
Resistance to
PTH
GFR
PTH
Ca2
FGF-23
Disturbed
mineralization
Calcitriol
MEPE
(Matrix extracellular
phospho-glycoprotein
Hyperparathyroid
bone

11. CKD-MBD Where can we act?
 Nutritional Vit D (Calcidiol level 50-100)
 PO4 poisoning: Limit inorganic intake
 binders
 Proton Poisoning (acidosis)
 Ca++ not needed !!
 PTH Phosphaturic toxin
 FGF 23

12. My Pill will fix it!!!

13. Vit Ds and VDRA’s
 Steroid Hormones (Seco Steroids)
 Not true vitamins : skin can make it (naked in sun)
 Receptors in multiple cells and tissues
 All Vit D’s can activate receptor at different doses
 Activation in Steps
 Liver 25-OH
 Kidneys and multiple tissues 1-OH
 1,25-OH Endocrine, Paracrine, Autocrine effects
 1,25-OH circulating levels = little meaning
 Physiology different from Pharmacological !!

14. Zehnder D J (2001 ) Clin Endocrinol Metab. Feb;86(2):888-94
• skin (basal keratinocytes
• hair follicles)
• lymph nodes (granulomata)
• colon (epithelial cells and parasympathetic
ganglia)
• pancreas (islets)
• adrenal medulla
• brain (cerebellum and cerebral cortex),
• placenta (decidual and trophoblastic cells).
Extrarenal distribution of 1
alpha-hydroxylase

15. Vit D Receptors :
Vitamin D receptor (VDR) is a member of the nuclear
receptor superfamily of ligand-activated
transcription factors
 RARs (retinoic acid receptors)
 TRs (thyroid hormone receptors)
 GRs (glucocorticoid receptors)
 ERs and PRs (estrogen and progesterone receptors)
 PPARs (peroxisome proliferator-activated receptors)
 *RXRs (retinoid X receptors)
McDonnell DP, Science. 235:1214-1217, 1987.
Baker, et al. Proc Natl Acad Sci U S A. 85 (10): 3294–3298, 1988.

16. System Tissue
Gastrointestinal Esophagus, stomach, small intestine, large intestine, colon
Arterial Vessels Vascular smooth muscle cells
Hepatic Liver parenchyma cells
Renal Proximal and distal tubules, collecting duct
Endocrine Parathyroid, pancreatic b-cells, thyroid C-cells
Exocrine Parotid gland, sebaceous gland
Reproductive Testis, ovary, placenta, uterus, endometrium, yolk sac,
Immune Thymus, bone marrow, B cells, T cells
Respiratory Lung alveolar cells
Musculoskeletal Osteoblasts, osteocytes, chondrocytes, striated muscle
Epidermis/appendage Skin, breast, hair follicles
Central nervous system Brain neurons
Connective tissue Fibroblasts, stroma
Vitamin D Receptor Distribution

17. Action of Vitamin D
Classical Actions
Calcium / Phosphorus
Homeostasis
Non-Classical Actions
Regulation of cell proliferation
and differentiation
Regulation of immune function
Endocrine effects Insulin resistance
Inflammation
Modulation of the renin-
angiotension system
Hypertension
Renal Function
Muscle function
Remuzzi, A. Vitamin D, insulin resistance, and renal disease.
Kidney Int. (2007) 71, 96-98.

18. Current data associates vitamin D deficiency with
multiple disorders (25-OH = Calcidiol deficit)
 Cancer
 Albuminuria CKD progression
 Insulin Resistance
 Secondary Hyperparathyroidism
 Cardiovascular Disease
 Carotid thickening
 Hypertension
 Early mortality Plain/Dialysis
 Define Deficiency when PTH elevated??

19. Vitamin D Deficiency/Insufficiency Rickets Targets
25(OH)D serum levels For Bones only
< 15 ng/mL Deficiency < 37.5 nmol/L
>15, <30 Insufficiency 37.5 -75
≥ 30 ng/mL Replete ≥ 75 nmol/L

20. 25-Hydroxyvitamin D [25(OH)D] /Health
NIH 2012
nmol/L ng/mL* Health status
<30 <12
Associated with vitamin D deficiency, leading to rickets in infants
and children and osteomalacia in adults
30–50 12–20
Generally considered inadequate for bone and overall health in
healthy individuals
≥50 ≥20
Generally considered adequate for bone and overall health in
healthy individuals PTH at baseline in healthy persons
>125 >50
Emerging evidence links potential adverse effects to such high
levels, particularly >150 nmol/L (>60 ng/mL)

21. Everyone Blindly or
25-OH = Calcidiol 50-100
Regardless PTH
Not as Rx; as Basic nourishment
VDRA’s not enough!!!!
Different from Rx VDRA’s
Recommended not proven yet
http://drholick.com

22. Phosphorus as Poison
 Normal and vital ion
 Linked to Protein in food but added
 CKDII+ : body keeps balance without high level but at
a price : PTH ; tissue deposition
 Ca x PO4 = active process like osteogenesis
 Remain “Normal” range until late CKDIV
 Normophosphemia in CKD NOT ENOUGH
 TRP FEPO4 needs monitoring !!!

23. Phosphorus
Very Common 1% weight;
< 0.03 % dialyzable
Constituent/chelated/inorganic
Intake 800-2700 mg/day (added)
Absorption Passive + active
Regulated?
Excretion : Renal Regulated by
Phosphatonins PTH, FGF23 others
Is there safe limit? MDR?

24. Phosphorus Additives
 Dicalcium Phosphate
 Hexametaphosphate
 Monocalcium Phosphate
 Phosphoric Acid
 Pyrophosphate
 Sodium Acid Pyrophosphate
 Sodium Aluminum Phosphate
 Sodium Phosphate
 Sodium Tripolyphosphate
 Tricalcium Phosphate

25. Why PO4 additives
Worldwide use ; USA 4x increase
 Leavening
 • pH Contrrol
 • Suspension/dispersion agent
 • Anti caking
 • Decrease cooking time
 • Emulsifier
 • Stabilizer
 • Moisture binding
 • Improve texture
 • Maintain color or firmness
 • Flavor enhancer

26. PO4 Absorption is active : Na/PO4 Cotransporter
 Inhibiting decreases Na & PO4 absorption
 Dream pill 2/day
 Binders crank up CoTransporter = Do not skip!!
 Niacin alone or plus Laropiprant (antiflushing)
 Phosphonoformic Acid (Foscarnet)
 Others under research

27. *Adjusted for baseline age, sex, race, cerebrovascular disease, diabetes, ischemic heart disease, HF, acute renal failure, calcium intake
from medications, serum calcium, inverse of baseline creatinine, time-averaged creatinine, slope of creatinine, maximal creatinine
concentration, and hemoglobin.
Baseline CrCl: 39.5 – 50.4 mL/min.
Kestenbaum B et al. J Am Soc Nephrol. 2005;16:520-528.
Serum Phosphorus and Mortality Risk
in CKD Patients Not on Dialysis
1.00
1.15
1.32 1.34
1.90
Serum Phosphorus (mg/dL)
5%
88%
7%
1.83
n=6730
1.0
0.0
<2.5 2.5-3.49 3.5-3.99 4.0-4.49
AdjustedHazardRatio
forMortality*
4.5-4.99 ≥5.0
2.0

28. 50 40 30 20 1060
Adapted from Kestenbaum B et al. J Am Soc Nephrol. 2005;16:520-528.
Phosphate(mg/dL)
2
3
4
5
6
90 80 70
Cockcroft-Gault Estimated Creatinine Clearance (mL/min)

29. Trade Off Hypothesis
 In CKD < V hyperphosphemia rare
 Filtered load decreases with decreasing GFR
 Diet/ Absorption unchanged:
 FEPO4 must increase (TRP decrease)
 Phosphatonins (Hormones to pee PO4):
 PTH’s
 FGF 23
 Others under study and synthesis (MEPE)

30. Trade Off Hypothesis
Bricker NS: NEJM 286: 1093-1099, 1972

31. Prevalence of Abnormalities of Mineral Metabolism PTH in CKD
(n = 61) (n = 117) (n = 230) (n = 396) (n = 355) (n = 358) (n = 204) (n = 93)
CKD Stage 3
CKD Stages 4 and 5
%ofPatients
eGFR (mL/min/1.73 m2)
0
10
20
30
40
50
60
70
80
90
100
79-70 69-60 59-50 49-40 39-30 29-20 <20
iPTH >65 pg/mL
Phosphorus >4.6 mg/dL
Calcium <8.4 mg/dL
eGFR = estimated glomerular filtratron rate; iPTH = intact PTH.
Adapted from Levin A et al. Kidney Int. 2007;71:31-38.
>80

32. CV Risk = even non- CKD PO4 correlates
Impaired endothelial function
Renal Interstitial fibrosis / CKD progression
Accelerated Vascular calcification

33. Phosphatonins can be toxic
 PTH : Bone , CV, Neuropathy ; associated incr.
Mortality
 FGF 23 : LVH, Vascular ; associated incr. Mortality
 Others : Not clearly identified
 Arterial Calcification is active cell mediated process
resembling Osteogenesis; not simply CaxPO4
 Which are Calcification mediators??

34. Dialysis removal PO4 poor
 Inorganic PO4 added to diet : well absorbed
 Constituent Organic PO4 or Chelated (phytate ) little
bioavability
 Diet restriction should center inorganic added
 Binders needed until absorption blockers out

35. Binders Aluminum
 Aluminum Hydroxide, Sucralfate
 Strongest binders; Constipation
 Al+3 Toxicity : Bone , Bone Marrow, Brain
 Levels > 50-100 warn; slow > 2-3 years
 All toxicity occurred before levels could be measured
 Most came from dialysis water with Aluminum
 Most nephrologists do not use them but there is role

36. Binders : Calcium
 Ca Acetate (Not Citrate) 667 = 169 mg;
 Carbonate .5 = 199.6 mg
 Rather effective but Silent toxicity
 Hypercalcemia rare
 Maximum dose ? 3-4 pills day TOTAL
 Old limits CaAc 9 CaCarb 5 pills
 MDR for CKD undefined : very low!!
 Do not use if
 tCa++ > 9.5- 10; PTH< 300; Ion product > 65-70
 Interactions : Quinolones, Vit D’s , Thyroid, CCB’s,
Tetracyclins

37. Probability of All-Cause Survival According to
Calcification Status
*Comparison Between Curves Was Highly Significant (x2=42.66, P<0.0001)
Blacher A, et al. Hypertension: Vol 38, pp 938-942, October 2001
0 Arteries Calcified
1 Artery Calcified
2 Arteries Calcified
3 Arteries Calcified
4 Arteries Calcified
ProbabilityofSurvival
0.00
0.25
0.50
0.75
1.00
Duration of Follow-Up (Months)
0 20 40 60 80
P<0.0001
n = 110

38. Medial CalcificationIntimal Calcification
Vascular Calcification

39. Binders: Magnesium
 Mg Hydroxide, Magnebind (with Calcium
 Follow Mg++
 Maximum level 3.5-3.8 : toxic
 Diarrhea
 Directly inhibits PTH
 Is that good ?
 Consider if Ca++ included

40. Binders: Sevelamer
 Sevelamer HCl; Carbonate; others
 Weak , more expensive
 Drug interaction: Thyroid, Vit D ,E & K, Calcitriol,
Quinolones, Tetracyclines
 Non Toxic : risk Obstruction
 Lower Bad Cholesterol
 May improve mortality vs. Ca binders

41. Binders : Lanthanum Carbonate
 Second only to Al+3 in power
 Soon as powder (homemade also)
 Non Toxic
 Cost, tolerance
 Drug Interactions : Thyroid , Vit D’s , Quinolones,
Tetracyclines

42. Binders: Iron
 Velphoro = Sucroferric oxyhydroxide =
 1 per meal
 Higher MW
 Auryxia =Ferric Citrate =
 2-3 tabs 1 gram each per meal
 Lower MW
 So far no Al+3 toxicity x 1y exposure
 Both GI problems; dark stools. Some iron absorption;
may trigger false OBS?

44. 1 84
847
37
53

45. 1
4
7
8
10
15
37
24
28
34
43
84
84
84
84
84
84
84
84
84
84
84
Capture AbDetector Ab or Detector Ab
First-generation IMA
Second-generation IMA
1
Diagram of the multiple species of PTH peptides in the circulation. The major forms are depicted with heavy lines. The grey areas
depict the regions of the PTH sequence that are detected by various antibodies for first-generation and second-generation
immunometric assays and indicate the PTH peptides that would be detected in each assay. The symbol ( ) depicts a PTH 1-84
peptide that is likely post-translationally modified in a region which interferes with its detection by first-generation immunometric
assays.
Circulating PTH Peptides

46. Normal Uremia
Not all PTH is active only in RED
Some blocks PTH action
1-84 PTH "7-84" Mid/C PTH
From Brossard et al Seminars in Dialysis 15: 196, 2002
80%
15%
5%
2%
2%
96%

47. Klotho allows FGF 23 action

49. Scientific basis for using VDRA’ s to Rx hyperpara CKDV
“Current vitamin D therapy in ESRD appears largely
based on the dramatic responses we described in
the 1970s. These responses were seen in an highly
selected group of patients with very severe disease.
We did not study asymptomatic patients or patients with
mild/moderate PTH elevations, patients who make up
the bulk of those now treated with calcitriol and its
descendants.
> So, whether we are harming or benefitting such
patients with our current approaches is quite unclear to
me. I suspect in these patients, the complications of
treatment may well outweigh the benefits”
Don Sherrard NEPHROL
Cochran Collaboration 2009 Issue 4 = no data to support any VDRA more

50. Many Studies Show a Clinical
Advantage for VDRA Therapy
 Decrease in mortality:
 Teng et al., J Am Soc Nephrol. 2005;16:1115-1125
 Kalantar-Zadeh et al., Kidney Int. July 2006
 Tentori et al, Kidney Int. Oct 2006
 Lee et al, J Renal Nutr. 2007
 Melamed et al, Kidney Int. March 2006
 Young EW et al, ASN Proceedings 2005 TH-PO735 (DOPPS study)
 Wolf et al., ASN Proceedings 2006 TH-FC 093
 Spiegel DM, et al. ASN Proceedings 2006 F-FC080
 Schumock et al., ASN Proceedings 2006 SA-PO340
 Naves et al., ASN Proceedings 2006 TH-PO977 and TH-PO976 (CORES study)
 Japanese Society for Dialysis Therapy Ann. Report 1999
 Decrease in hospitalizations:
 Go et al., NEJM 2004; 351: 1296-1305
 Dobrez DG et al, Neph Dial. Trans. 2004; 19(5): 1174- 1181
 Tentori et al., ASN Proceedings 2006 SA-PO577
 Melnick et al, 25th Ann Dialysis Conf. 2005 Proceedings, 9 (1):90-90

51. What is ahead in pipeline
“Son of Cinacalcet” =R568
2-Chloro-N-[(1R)-1-(3-methoxyphenyl)ethyl]-benzenepropanamine HCl
“Son of Sevelamer” Japan 13 Pt’s
Chitosan chewing Gum
PO4 absorption blockers
Alcohol injection Parathyroids??
More Indirect Studies Few Survival Studies:
IMPACT-SHPT “Paricalcitol or Cinacalcet centered ..markers CKD-
MBD” Neph Dial Transp 2014: Feb 4 (Epub)
iPTH 300-800 PO4 < 6.5 = Paricalcitol won

52. What do I do ?
Keep reading critically
New Binders , PO4 blockers
Supplement nutritional VitD
Avoid Proton Poisoning
CKD Follow PO4 + TRP
Limit added inorganic PO4
Binders : Ca/Non Ca
PTH Rx only if Alk Phos

53. Our Job in CKD-MBD

54. CKD V :Not all Poisons are equal :
High Ca > 10-11 : short term toxic
Low Ca Harmless unless Tetany : no need to Rx !! Except hypoparathyroidism
PO4 : Slowly toxic : no level safe ? > 2-2.5 ??
Low PO4 marker malnutrition
PTH : Wide range with few toxic effects
Low worse than High still weak poison
K : Acute high > 6 -6.5 ; slow can tolerate better : EKG
Low (< 3.5-3.8) predialysis a risk if bath K low
Mg 3-3,5 OK over 4-6 respiratory depression
Al+3 : takes years to build up ; over 100 toxic

55. And the Emperor was Naked…
Calcitriol = 1,25
Circulating Hormone only made kidney
1,25 level important
Bone Heath
Aluminum binders not absorbed
Corn, Beans are high in Phosphorus
Control PTH by high bath Calcium (Ca =3.5)
Ca binders good for you: Strong bones /lower PO4
If KT/V OK you are OK = Express Dialysis
Vit D analogs will cure PTH; use plenty
Cinacalcet replaces parathyroidectomy
Paricalcitol safer than Hectorol or Calcitriol
Nothing beats steel for PTH

56. My Rx scheme 3/15
Do as little harm as possible within ignorance
PTH Ca Binders VDRA's Cinacalcet
< 200 No No No
200-300 OK Yes No
> 300 OK Yes Yes
> 1000 OK Yes ?? Yes ??
tCa Ca Binders VDRA's Cinacalcet
9.8-10 No ?? Yes
< 9.8 Yes Yes if high PTH Alk
>10 No No Yes
Caveats : Respect Max Ca dose (Antacids ) ; Ca x PO4 < 70; Parathyroidectomy ??
Avoid Ca overload > HyperCa
Rx PTH = Not proven much help to Pt’s but need Chart buffed

57. Thank you !!
 Jorge Roman-Latorre MD
 ElTote@Hotmail.com

58. STOP
Slide Show

59. Toxic Fosfatonins
 PTH no longer only one:
 FGF-23
 produced by osteocytes
 reduce the renal resorption of phosphate,
 reduce 1,25 vitamin D levels
 suppress PTH levels
 “master regulator of the calcium-phosphate cross
product,”
 CV Toxic ??
 Others under study

60. Trade off Hypothesis
 Normal SPO4 = 4 mg/dl filters 57600 mg in 24h
excretes 900 = reabsorbs 99%
 CKDIV also SPO4 = 4 mg/dl filters 5760 mg in 24h but
reabsorbs only 70% or less
 Keep SPO4 fairly constant by cutting back
reabsorption = trade off
 Phosphatonins regulate (PTH, FGF23 ,others)

61. Management CKD-MBD II 2012
VDRA’s to control overactive/overgrown PTHs
Not a simple problem of SS VDRA’s/Cinacalcet/Binders :
Calci(fe)diol/Calcitriol/
Paricalcitol/Doxercalciferol
Calcimimetics : Cinacalcet/ R568 iv
Parathyroidectomy Subtotal/ Total + autograft
ETOH Injection (only Japan)
Avoid Low Turnover/Adynamic Bone Dx !!
PTH < 2 x upper limit
true hypocalcemia :
DC Calcimimetics, VDRA’s