Differential Diagnosis for a 15-month-old girl with delayed crawling and walking
- Single most likely diagnosis:
- Rickets: The widening of the wrists and delayed crawling and walking are suggestive of rickets, a disease caused by vitamin D deficiency, which is common in exclusively breast-fed infants who are not receiving vitamin D supplements. The lack of sun exposure and limited dietary sources of vitamin D in breast milk contribute to this deficiency.
- Other Likely diagnoses:
- Vitamin D deficiency: This is closely related to rickets and can cause similar symptoms, including delayed motor development and widening of the wrists.
- Hypophosphatasia: A rare genetic disorder that affects the breakdown and reuse of certain minerals, including phosphorus, leading to softening of the bones and delayed development.
- Do Not Miss diagnoses:
- Congenital hypothyroidism: Although the child's length and weight are within normal percentiles, and language and social skills are appropriate, congenital hypothyroidism can cause delayed motor development and should not be missed due to its potential for severe consequences if left untreated.
- Muscular dystrophy: A group of genetic disorders characterized by progressive muscle weakness and degeneration, which could explain the delayed crawling and walking.
- Rare diagnoses:
- Osteogenesis imperfecta: A genetic disorder that affects the production of collagen, leading to fragile bones and potential for fractures, which could contribute to delayed motor development due to pain or fear of movement.
- Achondroplasia: A genetic disorder that affects bone growth, leading to short stature and potential for delayed motor development, although this would typically be accompanied by other distinctive physical features.