Hypercalciuria
Download
1 / 18

Hypercalciuria - PowerPoint PPT Presentation


  • 104 Views
  • Updated On :

Hypercalciuria. William van’t Hoff Great Ormond Street Hospital London. Hypercalciuria: relevance. Commonest metabolic abnormality in paediatric urolithiasis & nephrocalcinosis Found in 30% paediatric stone formers Strongly related to dietary intake (e.g. of sodium)

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Hypercalciuria' - tablita


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
Hypercalciuria l.jpg
Hypercalciuria

William van’t Hoff

Great Ormond Street Hospital

London


Hypercalciuria relevance l.jpg
Hypercalciuria: relevance

  • Commonest metabolic abnormality in paediatric urolithiasis & nephrocalcinosis

  • Found in 30% paediatric stone formers

  • Strongly related to dietary intake (e.g. of sodium)

  • Associated with negative calcium balance (e.g. reduced bone mineral density in ~ 30% at diagnosis)


Hypercalciuria presentation l.jpg
Hypercalciuria: presentation

  • Haematuria

  • Dysuria

  • Polyuria / polydipsia / enuresis

  • Abdominal pain (stones)

  • Features of an underlying cause (e.g. Fanconi syndrome)

  • Asymptomatic


Hypercalciuria definitions l.jpg
Hypercalciuria: definitions

  • Second morning urine calcium/creatinine ratio < 0.74 mmol / mmol

  • Variation in reported normal ranges (population sampled, timing of sampling, age)

  • 95th centile changes from 2.2 to 0.7 mmol/mmol between 1 month and 14 years

  • 24 hour urine > 0.1 mmol (4mg) /kg/day

  • Urine Ca/Osm if muscle mass reduced (Richmond et al. Clin Nephrol. 2005. 64:264-70)



Idiopathic hypercalciuria l.jpg
Idiopathic hypercalciuria 1997-2007) n=250

Most children with hypercalciuria have

no currently definable renal, skeletal or

gastrointestinal defect - Idiopathic


Idiopathic hypercalciuria candidates l.jpg
Idiopathic hypercalciuria: candidates 1997-2007) n=250

  • Vitamin D receptor (VDR)

  • Calcium sensing receptor (CaSR)

  • Epithelial calcium channel (ECaC)

  • Adenylate cyclase

  • Crystallisation inhibitors:

    • Osteopontin

    • Tamm-Horsfall protein (uromodulin)

    • Ostoecalcin related gene (ORG)

  • No positive results to date

  • Polygenic trait (50% first degree relative)


Hypercalciuria tubulopathies rare l.jpg
Hypercalciuria: Tubulopathies (rare) 1997-2007) n=250

  • Proximal

    • Fanconi syndromes (some)

    • Dent’s disease

    • Lowe’s syndrome

    • HHRH

  • TAL:

    • Bartter’s syndrome (some)

    • Hypomagnesaemia / hypercalciuria

    • CaSR activating mutation

  • Distal

    • dRTA

    • PHAII


Hypercalciuria normocalcaemia l.jpg
Hypercalciuria: Normocalcaemia 1997-2007) n=250

  • Ex-premature infants (multifactorial)

  • Ketogenic diet (40% at start, 75% after 6 months, 1 in 20 develop stones, hypocitraturia ± immobility)

  • Drugs (furosemide, topiramate, acetozolamide)

  • Glycogen storage disease type 1 (+ hypocitraturia)

  • Beckwith Wiedemann syndrome

  • Vesico-Ureteric reflux / PUJ obstruction


Hypercalciuria hypercalcaemia rare l.jpg
Hypercalciuria: Hypercalcaemia (rare) 1997-2007) n=250

  • Vitamin D toxicity

  • Primary hyperparathyroidism

  • Hypophosphatasia

  • Alactasia

  • Williams syndrome

  • Thyrotoxicosis

  • Sarcoidosis


Idiopathic hypercalciuria risk of stone formation recurrence l.jpg
Idiopathic hypercalciuria: risk of stone formation / recurrence

  • Risks of stone formation in long term follow up studies varies between 3 and 33%

  • Variation in part due to different study groups

  • May be other confounding variables: e.g.hypocitraturia and hyperoxaluria more frequent in calcium stone formers


Hypercalciuria assessment l.jpg
Hypercalciuria: assessment recurrence

  • Confirm if possible with 24 hour urine or repeated spot samples (age-matched reference range)

  • Exclude secondary causes:

    • check renal tubular function

    • check plasma Ca, Mg, Vit D, PTH

    • check for nephrocalcinosis

  • Bone mineral density if history of fractures or osteoporosis


Hypercalciuria management l.jpg
Hypercalciuria: management recurrence

  • Many do not need treatment

  • Consider intervention if:

    • recurrent / severe stone disease

    • nephrocalcinosis

    • tubulopathies ( with caution)

    • impaired GFR

    • history of fractures / osteoporosis


Hypercalciuria diet l.jpg
Hypercalciuria: recurrencediet

  • Children with persistent HC have higher Na excretion than those in whom HC resolves (Polito Nephron, 2002)

  • Low sodium/high potassium can reduce calcium excretion by 50% in trial conditions (Alon,Berenbom Ped Nephrol 2000)

  • In adult females, increased dietary calcium intake associated with reduced stone formation but calcium supplements with increased stone risk (Curhan Ann Int Med 1997)

  • Reduced protein and salt / normal calcium intake, reduced stone risk in adult males compared to low calcium diet (Borghi NEJM 2002)


Hypercalciuria medication l.jpg
Hypercalciuria: medication recurrence

  • Potassium citrate:

    • increases urine pH, citrate and reduces urine calcium & oxalate supersaturation

    • reduces stone recurrence

  • Thiazides:

    • reduce urine calcium

    • restore bone mineral density

  • Combination (with low calcium and oxalate diet) reduced stone recurrence by 98%, improve BMD (Pak et al. J Urol 2003)

  • Bisphosphonate therapy improves BMD and reduces hypercalciuria


Bisphosphonates in hypercalciuria freundlich alon ped neph epub 2008 l.jpg
Bisphosphonates in hypercalciuria recurrence(Freundlich & Alon Ped Neph epub 2008)


Hypercalciuria summary l.jpg
Hypercalciuria: recurrence summary

  • Common metabolic abnormality with or without urolithiasis / nephrocalcinosis

  • Often associated with reduced bone mineral density

  • Requires careful evaluation

  • Usually has good prognosis for the kidney

  • If necessary, treatment combines dietary and pharmacological interventions


ad