Hypophosphatemic Rickets Medication
- Author: Karl S Roth, MD; Chief Editor: Stephen Kemp, MD, PhD more...
Medication Summary
Treatment options include calcitriol, GH, phosphates, and anticalciurics to promote healthy bone growth and diminish mineral loss associated with hypophosphatemic rickets. As previously stated, acute hypercalcemia (with resulting irritability, confusion, and potential seizures) can occur during treatment. Nephrocalcinosis, the long-term result of overaggressive therapy, may be more damaging.
Unless a concomitant GH deficiency is observed, administration of biosynthetic GH for growth promotion has not been approved, unless GH deficiency is observed. Only preliminary evidence of improved final height with GH therapy has been reported.[4]
Vitamin D
Class Summary
Standard protocol for treatment of familial hypophosphatemic rickets includes the use of 1,25-dihydroxy-vitamin D (calcitriol). The use of calcitriol in place of standard vitamin D obviates near-toxic dosage of the latter, avoids fat storage of parent vitamin D, and diminishes the danger of hypercalcemia.
Calcitriol (Rocaltrol)
Calcitriol increases calcium levels by promoting calcium absorption in the intestines and retention in kidneys.
Phosphate replacement
Class Summary
Massive urinary phosphate loss is a problem intrinsic to the disorder, and the phosphate must be replaced.
Potassium phosphate/sodium acid phosphate (K-Phos Neutral, Phos-Nak)
This is a neutralized, buffered, oral phosphate-replacement solution containing 250 mg phosphorus, 280 mg potassium, 160 mg sodium . It is a combination of sodium and potassium phosphate.
Diuretics
Class Summary
Thiazides are anticalciuric, an effect that can assist in counteracting the tendency for bone calcium loss.
Hydrochlorothiazide (Microzide)
Hydrochlorothiazide is a well-known diuretic with antihypertensive action. It inhibits reabsorption of sodium in distal tubules, causing increased excretion of sodium and water, as well as of potassium and hydrogen ions. Hydrochlorothiazide is not metabolized and is rapidly excreted in the urine.
Amiloride
Hypokalemia is a hazard when kaliuretic-effect thiazides are used; this danger that can be counteracted with the use of a second diuretic. Amiloride has a well-characterized antikaliuretic effect. Often used together with thiazides for its synergistic antihypertensive effects, amiloride has the benefit of decreasing potassium loss. Thus, it is a useful adjunct in the treatment of patients with familial X-linked hypophosphatemia with thiazides, in whom hypokalemia is a risk.
Roth KS, Ward RJ, Chan JCM, Sarafoglou K. Disorders of calcium, phosphate and bone metabolism. In: Sarafoglou K, Hoffmann GF, Roth KS, eds. Pediatric Endocrinology and Inborn Errors of Metabolism. New York, NY: McGraw Hill; 2009:619-64.
Prié D, Friedlander G. Genetic disorders of renal phosphate transport. N Engl J Med. Jun 24 2010;362(25):2399-409. [Medline].
Ariceta G, Langman CB. Growth in X-linked hypophosphatemic rickets. Eur J Pediatr. Apr 2007;166(4):303-9. [Medline].
Haffner D, Nissel R, Wuhl E, Mehls O. Effects of growth hormone treatment on body proportions and final height among small children with X-linked hypophosphatemic rickets. Pediatrics. Jun 2004;113(6):e593-6. [Medline].
Sochett E, Doria AS, Henriques F, et al. Growth and metabolic control during puberty in girls with X-linked hypophosphataemic rickets. Horm Res. 2004;61(5):252-6. [Medline].
Bastepe M, Jueppner H. Inherited hypophosphatemic disorders in children and the evolving mechanisms of phosphate regulation. Rev Endocr Metab Disord. Jun/2008;9:171-180.
Baum M, Syal A, Quigley R, Seikaly M. Role of prostaglandins in the pathogenesis of X-linked hypophosphatemia. Pediatr Nephrol. Aug 2006;21(8):1067-74. [Medline].
Jehan F, Gaucher C, Nguyen TM, et al. Vitamin D receptor genotype in hypophosphatemic rickets as a predictor of growth and response to treatment. J Clin Endocrinol Metab. Dec/2008;93:4672-4682.
Cho HY, Lee BH, Kang JH, et al. A clinical and molecular genetic study of hypophosphatemic rickets in children. Pediatr Res. Aug 2005;58(2):329-33. [Medline].
Bresler D, Bruder J, Mohnike K, et al. Serum MEPE-ASARM-peptides are elevated in X-linked rickets (HYP): implications for phosphaturia and rickets. J Endocrinol. Dec 2004;183(3):R1-9. [Medline].
Segawa H, Kaneko I, Tomoe Y, et al. The roles of Na/Pi-II transporters in phosphate metabolism. Bone. Feb/2009;Epub:Epub.
Beck-Nielsen SS, Brock-Jacobsen B, Gram J, et al. Incidence and prevalence of nutritional and hereditary rickets in southern Denmark. Eur J Endocrinol. Mar/2009;160:491-497.
Verge CF, Lam A, Simpson JM, Cowell CT, Howard NJ, Silink M. Effects of therapy in X-linked hypophosphatemic rickets. N Engl J Med. Dec 26 1991;325(26):1843-8. [Medline].
Alon US, Monzavi R, Lilien M, et al. Hypertension in hypophosphatemic rickets--role of secondary hyperparathyroidism. Pediatr Nephrol. Feb 2003;18(2):155-8. [Medline].
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