[MIM 143 880]

(Lightwood syndrome)

Very rare. Autosomal recessive transmission of a mutation of the CYP24A1 gene (20q13.2). This mutation results in an exaggerated response to vitamin D. A similar mutation causes hypercalcemia in infants receiving excessive doses of vitamin D. 

Hypercalcemia appears between 6 and 12 months, is accompanied by hypercalciuria and often nephrocalcinosis and heals spontaneously around the age of 2 years. There is also a low level of parathyroid hormone and high blood levels of 1,25-dihydroxyvitamin D. Hypercalciuria and nephrocalcinosis may persist after the correction of the hypercalcemia.

Hypercalcemia is sometimes associated with vomiting, dehydration and nephrocalcinosis. There is neither facial dysmorphism or growth retardation.

Treatment: reduction of the dietary intake of calcium (Locasol© milk by Nutricia) and prophylactic doses of vitamin D limited to 400 IU/day.

Anesthetic implications: 

check the absence of hypertension associated with nephrocalcinosis.

References : 

-         Castanet M, Mallet E, Kottler M-L. 
Lightwood syndrome revisited with a novel mutation in CYP24 and vitamin D supplement recommendations. 
Pediatr 2013 ; 163 : 1208-10.

Updated: March 2019