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Site Clinical features
Thorax Rachitic rosary
Harrison’s sulcus
Pectus carinatum
Spine and
pelvis
Kyphosis
Scoliosis
Lumbar lordosis
Neuromuscular Hypotonia, pot belly
Delayed motor development
Tetany, seizures
- How does the age of onset of rickets help in the differential diagnosis of
rickets/osteomalacia?
The age of onset of rickets/osteomalacia is an important clue for differential
diagnosis as different disorders typically manifest at specific ages. These are
summarized in the table given below.
Age Etiology Remarks
Infancy Vitamin D deficiency Exclusively breast-fed infants
Vitamin D-dependent rickets type 1 Hypocalcemic tetany
Vitamin D-dependent rickets type 2 Alopecia
Hypophosphatasia Craniosynostosis
Low alkaline phosphatase
Hypercalciuria
Childhood Vitamin D deficiency Nutritional
Malabsorption
Celiac disease
Renal rickets Renal tubular acidosis
Proximal RTA
Fanconi’s syndrome
Isolated
Distal RTA
Chronic kidney disease
Familial hypophosphatemic rickets X-linked variant
Enthesopathy
Fractures Dental caries/dental
abscess
Hypophosphatasia Low alkaline phosphatase
Adult onset Vitamin D deficiency Bone pain, pseudo-fracture
Tumor-induced osteomalacia Severe hypophosphatemia
Familial hypophosphatemic rickets Autosomal dominant variant
Hypophosphatasia Stress fractures
Osteoarthritis
Low alkaline phosphatase
5 Rickets–Osteomalacia