Differential diagnosis of Vitamin D deficiency

Commonest

Nutritional Vitamin D deficiency +/- Ca deficiency.

Consider

• malabsorption
• phosphate deficiency
• liver disease
• renal disease
• anticonvulsant therapy
• hypophosphataemic rickets
• hypo and pseudohypoparathyroidism
• Vitamin D dependent rickets (types I & II)
• renal tubular tisorders
• tumour-induced.

(Vitamin D deficiency may be confused with skeletal dysplasia).