Rickets is softening and weakening of the growing bones in children, most often from too little vitamin D, calcium or phosphate. The growth plates do not mineralize well, which leads to bowed legs, slow growth and bone pain.
Key symptoms
- Bone pain or tenderness and reluctance to walk
- Late walking, slow growth or short stature
- Bowed legs or knock knees
- Late tooth eruption and dental problems
- Muscle weakness; cramps or seizures if calcium is very low
What you find on exam
- Height and weight plotted on a growth chart
- Widened wrists and ankles
- Bead-like swellings along the ribs (rachitic rosary)
- Bowed legs, soft skull or late closure of the fontanelle
Tests
- Calcium, phosphate and alkaline phosphatase
- 25-hydroxyvitamin D and parathyroid hormone
- Wrist or knee X-ray: cupped, frayed and widened growth plates
- Kidney function and urine studies if a renal or genetic cause is suspected
Treatment basics
- Vitamin D replacement, usually cholecalciferol
- Enough calcium from diet or supplements
- Treat the cause: diet, little sun exposure, malabsorption or kidney disease
- Phosphate and calcitriol for inherited low-phosphate rickets
- Repeat labs and X-rays to confirm healing
Red flags
- Seizures, tetany or stridor from low calcium
- Poor growth despite treatment
- No response to vitamin D, suggesting a genetic or renal cause
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Sources: NCCPA PANCE Content Blueprint; NBOME COMLEX-USA clinical presentations; AAMC Core Entrustable Professional Activities (Core EPAs). Written by Making Synapses. Making Synapses is not affiliated with these organizations.