High bone turnover persisting after vitamin D repletion: beware of calcium deficiency.
Treatment of vitamin D deficiency with vitamin D is a common procedure when taking care of elderly patients, calcium supplementation being added only when calcium dietary intake is insufficient. Here, we report the case of a 58-year-old female who was referred to our unit because of suspicion of Paget's disease of the skull, based on elevated serum alkaline phosphatase and high skull methylene diphosphonate-technetium uptake. She had been prescribed cholecalciferol (100,000 IU/month) and calcium salts for the past 7 months after discovery of severe vitamin D deficiency by her primary care physician. No specific skull bone lesions were observed on both X-ray and computerized tomography. Serum calcium, phosphate and 25(OH) vitamin D levels were normal, while serum C-terminal cross-linked telopeptide, bone alkaline phosphatase and calcitriol were high and daily urinary calcium excretion was low. We found that she had not been compliant with the calcium prescription while vitamin D had been thoroughly taken. We suspected osteomalacia due to calcium deficiency. Both skull uptake and biological abnormalities normalised in few months after adding calcium supplementation to the vitamin D treatment, and spine bone mineral density increased by 9.5 % after 14 months of full treatment. The present case illustrates the necessity for adequate calcium intake during vitamin D repletion to normalise bone mineralisation and turnover and maintain the skeletal integrity.
INSERM U1059, Université de Lyon, 15 Rue A PARE, 42023, Saint-Etienne, Cedex 2, France. lafagemh@univ-st-etienne.fr
M-H
MH
Lafage-Proust
L
L
Lieben
G
G
Carmeliet
C
C
Soler
C
C
Cusset
L
L
Vico
T
T
Thomas
D000469:Alkaline Phosphatase / Q000097:blood; D015519:Bone Density / Q000187:drug effects / Q000502:physiology; D016723:Bone Remodeling / Q000187:drug effects* / Q000502:physiology; D002118:Calcium / Q000097:blood / Q000172:deficiency* / Q000627:therapeutic use; D002762:Cholecalciferol / Q000627:therapeutic use*; D019587:Dietary Supplements; D005260:Female; D006801:Humans; D055118:Medication Adherence; D008875:Middle Aged; D010018:Osteomalacia / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology; D014808:Vitamin D Deficiency / Q000188:drug therapy* / Q000503:physiopathology
D002762:Cholecalciferol; D000469:Alkaline Phosphatase; D002118:Calcium