Rickets
Rickets is a condition that results in a loss of bone mineralisation (soft bones), or can be thought of as the paediatric version of Osteomalacia. It's caused by a deficiency in Vitamin D or Calcium.
Vitamin D is needed for calcium (Ca) and phosphate (Ph) absorption from the gut and kidneys, as well as regulating bone turnover and promoting bone reabsorption to boost Ca levels. A deficiency of it leads to a low Ca and Ph, therefore less bone mineralisation. This low Ca can also lead to secondary hyperparathyroidism as a result (raised PTH as a response).
Causes of Vitamin D deficiency:
Darker skin
Lack of sun exposure
Malabsorption e.g. IBD, Coeliac
CKD
Presentation
Bone deformity – Bowing of legs, Knock knees
Aching bones and joints
Pathological fractures
Lethargy
Investigations
25-Vit D - < 25 nmol/L is diagnostic of a deficiency
XR
Bloods – Ca, Ph, PTH, ALP, FBC, CRP, ESR, U&E, LFTs, TFTs, Anti-TTG
Management
Prevention – Breastfed babies are at higher risk of Vit D deficiency than formula fed (formula has a lot more Vit D)
Vit D supplementation - Ergocalciferol (Vit D)