Vitamin D–dependent rickets is a disorder that makes it hard for the body to use minerals in bones and muscles properly.
Common symptoms include slow growth, weak muscles, bowed legs, and wide wrists and ankles. These symptoms usually appear in the first two years of life, which can delay when a child starts walking or may require them to use walking aids. People with this condition might also have more bone fractures, bone pain, seizures, muscle spasms, dental problems, and hair loss.
There is no cure for this type of rickets, but treatment focuses on managing symptoms. This often includes taking medication (calcitriol) and calcium to correct problems with bones and body chemistry. Because of potential side effects, regular check-ups with physical exams, blood tests, and imaging tests like X-rays or ultrasounds are often needed to monitor the condition.
This condition is caused by pathogenic (disease-causing) variants in the CYP27B1 gene and exhibits autosomal recessive inheritance. This means that both parents must be carriers to have a 25% chance of having a child with the condition. The risk of being a carrier is based on a person’s ancestry or ethnic background.
Resources:
National Organization for Rare Disorders
Written August 2024
