Rickets Flashcards
Define rickets
A paediatric skeletal disorder caused by a deficiency or impaired metabolism of VitD, calcium or phosphate.
Results in inability to mineralise the bone matrix of growing bone causing soft and deformed bones
What is the relevant epidemiology of rickets?
Infancy or childhood
Less prevalent in developed countries due to improved nutrition and PH.
Common - asia (low sun and vegetarian)
Africa - darker skin pigmentation and famine
UK - more common in boys, children of Black or south Asian ethnicity.
What is the main aetiology of rickets?
Prolonged deficiency in VitD -> results in low absoprtion of calcium and phosphate
Cause:
Poor nutrition
Insufficient sun exposure
Malabsoprtion syndromes
What are the typical signs and symptoms of rickets?
Bowel legs or knock knees
Bone pain
Stunted growth
Dental deformities
Skeletal deformities - pigeon chest or spinal curvature
Rachitic rosary - swelling of cotstochondral junctions
Proximal muscle weakness
How can severe cases of rickets present?
Bone fragility and fractures
Hypocalcaemia - irritability, seizures and intellectual disability
Dilated cardiomyopathy
What are some important differentials for rickets?
Osteomalacia - adults
Hypophosphataemia - low ALP
Osteogenesis imperfecta - blue sclera and hearing loss
Hereditary hypophosphataemic rickets - X-linked, altered FGF23 - refractory vitD supplements
What laboratory testing should be done for rickets?
Bloods - calcium, phosphate and ALP
Sometimes 23-hydroxyvitamin D
Urinalysis - calcium and phosphate excretion
Require for diagnosis - 25OH vitD <25nmol/L and an abnormality in calcium/phosphate/PTH/ALP
What imaging can be used to diagnose rickets?
What are the positive signs?
X-rays
Cupping, fraying and metaphyseal widening.
What are the typical urinalysis results in rickets?
Low calcium
Inc phosphate
What are the typical blood results in rickets?
Low VitD
Low Ca2+
Low PO4-
High PTH
High ALP
What is the typical management plan for rickets?
Supplementation - VitD, calcium, phosphorus
Diet and lifestyle - inc sun, diet rich in D, C,P
Orthopaedic intervention - in severe cases with bone deformities
What are some potential complications of rickets?
Psychological due to chronic bone and joint pain
Dental caries secondary to dental deformities
Hypocalcaemia -> seizures, tetany, largyngospasm causing apnoea or stridor.
What is the typical prognosis of rickets?
Responds well to vitD supplementation with increased muscular strength and mobility
May experience temp inc in bony pain on initiation of VitD supplementation
