X-linked Vitamin-D Resistant Rickets
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[edit] Name of Condition
X-linked Vitamin-D Resistant Rickets, also known as X-Linked Hypophosphatemia (XLH), X-Linked Hypophosphatemic Rickets, Familial Hypophosphatemia, Vitamin D-Resistant Rickets (VDRR) or Genetic Rickets
[edit] Definition
This is a genetic condition that causes a "resistance" to Vitamin D, which is an important vitamin that helps form bones. Without the vitamin, bones become weak and afflicted persons have difficulty walking, and teeth are often week and develop abscesses. Adults are normally of significantly shorter stature.
[edit] Description, Signs and Symptoms
Symptoms usually being to appear when a child is learning to walk, when weakness or deformity in the legs will become apparent. THe legs may seem bowed, twisted, or knock-kneed. Children may have thick wrists, a pronounced forehead, and possibly rachitic rosary which is a small array of bony beads on the chest. The child's teeth may also be slow to grow in, and have frequent dental abscesses. The person may also be of very small stature. Rarely, there may be problems with bone development in the head, which would be recognized by a doctor relatively quickly.
[edit] Inheritance
This form of rickets is carried on the X chromosome. It may skip generations and therefore be difficult to diagnose due to a seeming lack of family history.
[edit] Demographics
This rare condition affects 1 in every 20,000 people.
[edit] Diagnosis
There are many potential causes of these symptoms, so it is not easy to diagnose, although if there is a family history of the disease it will be a more likely possibility. If there is not a family history, it may take several months or years to recognize the disease because it is quite rare, occurring in only 1 in every 20,000 births, so even experienced physicians would not be prepared to diagnose it quickly.
[edit] Treatment and Management
Once the disease is recognized, children are treated with a combination of medications such as Vitamin D and phosphorus supplements that should help increase bone straightening and structure. Sometimes additional support such as braces or surgery are necessary. Some other medications may affect the kidneys, so doctors will take blood or urine samples regularly.
[edit] Prognosis
With proper treatment and care, people with this condition can live full lives, although they will may have some significant physical differences from normal people with respect to height and stature.
[edit] Resources
http://xlhnetwork.org/site/Welcome.html
