Martin Konrad has documented that he has no relevant financial relationships to disclose or conflict of interest to resolve.

Transcription

1 Martin Konrad has documented that he has no relevant financial relationships to disclose or conflict of interest to resolve.

2 Nephrocalcinosis Clinical / Genetic Work-up and Outcome Martin Konrad University Children s Hospital Münster, Germany 48 th ESPN Meeting, Brussels 2015

3 Nephrocalcinosis in Children Introduction Diagnostic / genetic work-up Outcome

4 Extracellular calcium balance in adults Intake 1000 mg Intestine 300 mg 100 mg Serum Ca mg 8800 mg Kidney Feces 800 mg 200 mg 200 mg 200 mg Urine Bone

5 20 25 % Renal tubular calcium reabsorption free Calcium 5 7 % 55 70% 2 %

6 Introduction Nephrocalcinosis Is the differentiation between nephrocalcinosis and kidney stones disease always helpful? This question certainly is a question of the right perspective.

7 Introduction Nephrocalcinosis From the kidney stone perspective? Many stone-forming conditions carry no or little additional risk for the development of nephrocalcinosis. Examples: cystinuria Lesch-Nyhan syndrome xanthinuria...

8 Introduction Nephrocalcinosis From the nephrocalcinosis perspective? At least in some of the underlying disease entities, there is considerable overlap (within disease entities, in families, even within the same individuals. Examples: Primary hyperoxaluria CYP24A1 defects drta... Are younger children more susceptible for NC rather than stones?

9 Introduction Nephrocalcinosis Etiology of pediatric nephrocalcinosis (nephrolithiasis) higher rate of underlying metabolic abnormalities, as a consequence, higher risk of progression of nephrocalcinosis or stone recurrence (20 46 %).

10 Introduction Nephrocalcinosis Main risk factors in infants and children hypercalciuria hyperoxaluria hypocitraturia prematurity (steroids, hypocitraturia, diuretics) medication and intoxication tumor treatment strong genetic background monogenic disorders

11 Underlying disorders in pediatric NC Idiopathic Hypercalciuria Hypercalcemic disease states Fanconi syndrome Antenatal Bartter syndrome Familial hypomagnesemia / hypercalciuria Distal renal tubular acidosis CASR related (FHH) Metabolic diseases, e.g. primary hyperoxaluria...

12 Human genetic diseases and renal calcium reabsorption Dent s disease ClC5, OCRL Lowe syndrome OCRL HHRH SLC34A3 Fanconi syndrome HNF4A, EHHADH Fanconi Bickel GLUT2 Metabolic diseases PH1-3 Infantile Hypercalc CYP24A1 SLC34A1 Gitelman syndrome SLC12A3 EAST syndrome KCNJ10 PHA type II WNK1, WNK4, Cul3? drta AE1, ATP6B1, ATP6N1B Antenatal Bartter syndrome NKCC2 ROMK BSND Familial Hypomagnesemia with hyercalciuria CLDN16 CLDN19 CASR -related CASR Kidney stones CLDN14

13 Nephrocalcinosis in Children Introduction Diagnostic / genetic work-up Outcome

14 Pediatric nephrocalcinosis: work-up Past Medical History failure to thrive, growth retardation polyuria, polydipsia urinary tract infections (colicky) pain, hematuria medication, vitamin D/A supplementation family history

15 Pediatric nephrocalcinosis: work-up Ultrasound kidney morphology size, echogenicity nephrocalcinosis, concrements Radiography / CT scan rarely necessary (e.g. ureteral stones)

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17 Pediatric NC: cortical nephrocalcinosis Preterm infant, CLDN16 mutation Hypomagnesemia Hypercalciuria High risk of CRF U. Vester, Essen

18 medullary nephrocalcinosis, grade IIa 16 mo,, Williams Beuren syndrome, serume Ca > 3 mmol/l, hypercalciuria

19 medullary nephrocalcinosis, grade IIa, proximal tubular dysfunction after polychemotherapy

20 medullary nephrocalcinosis, grade IIb 10 y,, Idiopathic hypercalciuria

21 medullary nephrocalcinosis, grade III, CLDN16 mutation

22 Nephrocalcinosis - Imaging The morphologic appearance rarely allows a clue towards the etiology. Repeated analysis serves the assessment of progression and the occurrence of stones during the course of the disease.

23 diffuse nephrocalcinosis 9 weeks, advanced renal failure, primary hyperoxaluria type I

24 diffuse nephrocalcinosis ESRD, primary hyperoxaluria type I U. Vester, Essen

25 Pediatric Nephrocalcinosis: work-up Lab examination

26 Human genetic diseases and renal calcium reabsorption Dent s disease ClC5, OCRL Lowe syndrome OCRL HHRH SLC34A3 Fanconi syndrome HNF4A, EHHADH Fanconi Bickel GLUT2 Metabolic diseases PH1-3 Infantile Hypercalc CYP24A1 SLC34A1 Gitelman syndrome SLC12A3 EAST syndrome KCNJ10 PHA type II WNK1, WNK4, Cul3? drta AE1, ATP6B1, ATP6N1B Antenatal Bartter syndrome NKCC2 ROMK BSND Familial Hypomagnesemia with hyercalciuria CLDN16 CLDN19 CASR -related CASR Kidney stones CLDN14

27 Pediatric Nephrocalcinosis: work-up glucose amino acids uric acid Ca ++ PO 4-, Na +, K + salt water, Mg ++ Ca ++ Salt Mg ++ Ca ++

28 Pediatric Nephrocalcinosis: work-up Lab examination blood: BGA, Na, Cl, K, Ca, Mg, PO 4, gluc, crea uric acid, AP, (PTH, Vit D/A, oxalate) urine: osmolality, ph, gluc, prot, sediment, culture Ca, oxalate, uric acid, citrate, Mg, PO 4, crea, cystine, amino acids genetic testing upon results might be helpful

29 Pediatric Nephrocalcinosis: genetic work-up directed testing (conventional) if clinical diagnosis is clear examples: drta, Bartter sy, FHHNC what to do if the clinical diagnosis is less clear? choose candidates one by one? NGS screening using gene panels? Within the next years, daily practise will tend to NGS panels (even exomes?) also for diagnostic purposes

30 Pediatric Nephrocalcinosis: genetic work-up 1st study published in March 2015 Study cohort: 272 individuals with nephrolithiasis/nephrocalcinosis, including 106 children (16 with nephrocalcinosis). Consecutive recruitment from typical kidney stone clinics. NGS panel of 30 genes revealed a monogenic underlying cause in 40 patients (14.5 % overall, 20% of the pediatric cohort). The majority of mutations cause cystinuria. Halbritter et al, JASN 2015

31 Pediatric Nephrocalcinosis: genetic work-up further experience, at this meeting: P-316, Bockenhauer et al. NGS (37 genes) for tubular disorders (salt-wasting/drta), mutations found in 64/75 (85%). P-321, Schlingmann et al., collaboration with Neuber/Bergmann NGS (137 genes) targeting all tubular disorders including stones/nc, Pilot study: works well, all previously known mutations detected.

32 Nephrocalcinosis / Kidney Stones in Children Introduction Diagnostic / genetic work-up Outcome

33 Pediatric NC / NL Outcome (in Adult Life) main risk factors: hypercalciuria hyperoxaluria hypocitraturia strong genetic background monogenic disorders

34 Is Nephrocalcinosis per se a risk for CRF?, antenatal Bartter syndr ROMK mutation low risk for CRF, hypomagnesemia/hypercalciuria CLDN16 mutation high risk for CRF

35 Calcium reabsorption in the TAL CLDN16 ROMK

36 Pediatric NC / NL Outcome (in Adult Life) prematurity little morbidity in late adolescence? NC may disappear over time tumor treatment NC alone has a good prognosis hypercalcemic disease states mostly easy to treat, stable NC stones may occur later in life

37 Underlying disorders in pediatric NC/NL Outcome? Idiopathic Hypercalciuria unknown good? Antenatal Bartter syndrome FHHNC (claudin defects) Primary hyperoxaluria I Fanconi syndrome Dent /Lowe syndrome Primary metabolic disorders Distal renal tubular acidosis good, except BSND defects poor, ESRF frequent poor, often progressive variable, CRF possible often progressive CRF in general rather poor little risk of CRF

38 Underlying disorders in pediatric NC/NL Outcome? Idiopathic Hypercalciuria unknown good? Antenatal Bartter syndrome FHHNC (claudin defects) Primary hyperoxaluria I Fanconi syndrome Dent /Lowe syndrome Primary metabolic disorders Distal renal tubular acidosis good, except BSND defects poor, ESRF frequent poor, often progressive variable, CRF possible often progressive CRF in general rather poor little risk of CRF

39 Underlying disorders in pediatric NC/NL Outcome? Idiopathic Hypercalciuria unknown good? Antenatal Bartter syndrome FHHNC (claudin defects) Primary hyperoxaluria I Fanconi syndrome Dent /Lowe syndrome Primary metabolic disorders Distal renal tubular acidosis good, except BSND defects poor, ESRF frequent poor, often progressive variable, CRF possible often progressive CRF in general rather poor little risk of CRF

40 Underlying disorders in pediatric NC/NL Outcome? Idiopathic Hypercalciuria unknown good? Antenatal Bartter syndrome FHHNC (claudin defects) Primary hyperoxaluria I Fanconi syndrome Dent /Lowe syndrome Primary metabolic disorders Distal renal tubular acidosis good, except BSND defects poor, ESRF frequent poor, often progressive variable, CRF possible often progressive CRF in general rather poor little risk of CRF

41 Underlying disorders in pediatric NC/NL Outcome? Idiopathic Hypercalciuria unknown good? Antenatal Bartter syndrome FHHNC (claudin defects) Primary hyperoxaluria I Fanconi syndrome Dent /Lowe syndrome Primary metabolic disorders Distal renal tubular acidosis good, except BSND defects poor, ESRF frequent poor, often progressive variable, CRF possible often progressive CRF in general rather poor little risk of CRF

42 Underlying disorders in pediatric NC/NL Outcome? Idiopathic Hypercalciuria unknown good? Antenatal Bartter syndrome FHHNC (claudin defects) Primary hyperoxaluria I Fanconi syndrome Dent /Lowe syndrome Primary metabolic disorders Distal renal tubular acidosis good, except BSND defects poor, ESRF frequent poor, often progressive variable, CRF possible often progressive CRF in general rather poor little risk of CRF

43 Underlying disorders in pediatric NC/NL Outcome? Idiopathic Hypercalciuria unknown good? Antenatal Bartter syndrome FHHNC (claudin defects) Primary hyperoxaluria I Fanconi syndrome Dent /Lowe syndrome Primary metabolic disorders Distal renal tubular acidosis good, except BSND defects poor, ESRF frequent poor, often progressive variable, CRF possible often progressive CRF in general rather poor little risk of CRF

44 Underlying disorders in pediatric NC/NL Outcome? Idiopathic Hypercalciuria unknown good? Antenatal Bartter syndrome FHHNC (claudin defects) Primary hyperoxaluria I Fanconi syndrome Dent /Lowe syndrome Primary metabolic disorders Distal renal tubular acidosis good, except BSND defects poor, ESRF frequent poor, often progressive variable, CRF possible often progressive CRF in general rather poor little risk of CRF

45 Pediatric NC / NL CAVEAT Antenatal Bartter syndrome excessive hypercalciuria, early NC grade III NO THIAZIDES! DCT is important for compensating salt loss Hypercalciuria related to CASR mutations (FHH) hypocalcemic hypercalciuria calcium / vit D suppl induce massive NC

46 Thank you!