Oral calcium phosphate: a new therapy for Crigler-Najjar disease?
OBJECTIVE
Calcium phosphate binds unconjugated bilirubin in vitro, and dietary calcium phosphate supplementation reduces the serum bilirubin level in rats with hereditary unconjugated hyperbilirubinemia (Gunn rats). The aim of this study was to evaluate the effect of oral calcium phosphate supplementation on plasma bilirubin levels in patients with Crigler-Najjar disease.


METHODS
A placebo-controlled, double-blind, crossover design was used. Eleven patients, 2-42 years of age, participated. The group included 5 patients with type I disease who were all treated with phototherapy and 6 patients with type II disease who were primarily treated with phenobarbital. In addition to plasma bilirubin levels, dietary intake and urinary and fecal excretion of calcium and phosphate were evaluated.


RESULTS
A modest but significant decrease in serum bilirubin was observed in patients with type I disease (18% +/- 6%, P = 0.03) but not in patients with type II disease during treatment with calcium phosphate. Urinary output of calcium and phosphate did not change during the treatment period.


CONCLUSIONS
Oral calcium phosphate may be a useful adjuvant to photo-therapy in Crigler-Najjar type I disease.
Van der Veere
C N
CN
Department of Gastrointestinal Diseases, Academic Medical Center, Amsterdam, The Netherlands.
Jansen
P L
PL
Sinaasappel
M
M
Van der Meer
R
R
Van der Sijs
H
H
Rammeloo
J A
JA
Goyens
P
P
Van Nieuwkerk
C M
CM
Oude Elferink
R P
RP
D000284:Administration, Oral; D000328:Adult; D001663:Bilirubin / Q000097:blood; D002118:Calcium / Q000652:urine; D002130:Calcium Phosphates / Q000008:administration & dosage / Q000627:therapeutic use*; D002648:Child; D002675:Child, Preschool; D003414:Crigler-Najjar Syndrome / Q000097:blood / Q000188:drug therapy* / Q000652:urine; D018592:Cross-Over Studies; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D010710:Phosphates / Q000652:urine
D002130:Calcium Phosphates; D010710:Phosphates; C485828:alpha-tricalcium phosphate; C485830:tetracalcium phosphate; C485838:calcium phosphate, monobasic, anhydrous; C020243:calcium phosphate; C485829:calcium phosphate, dibasic, anhydrous; D001663:Bilirubin; D002118:Calcium