Many mutations are responsible for DMD, and some have not been identified, so genetic testing may be falsely negative if the suspected mutation in the mother has not been identified.Prior to invasive testing, determination of the fetal sex is important; while males are sometimes affected by this X-linked disease, female DMD is extremely rare. This can be achieved by ultrasound scan at 16 weeks or more recently by free fetal DNA (cffDNA) testing. Chorion villus sampling (CVS) can be done at 11–14 weeks, and has a 1% risk of miscarriage. Amniocentesis can be done after 15 weeks, and has a 0.5% risk of miscarriage. Non invasive prenatal testing can be done around 10–12 weeks. Another option in the case of unclear genetic test results is fetal muscle biopsy. Treatment
No cure for DMD is known, and an ongoing medical need has been recognized by regulatory authorities. Gene therapy has shown some success.Treatment is generally aimed at controlling symptoms to maximize the quality of life which can be measured using specific questionnaires, and include:

Corticosteroids such as prednisolone and deflazacort lead to short-term improvements in muscle strength and function up to 2 years. Corticosteroids have also been reported to help prolong walking, though the evidence for this is not robust. Randomised control trials have shown that β2 agonists increase muscle strength, but do not modify disease progression. Follow-up time for most RCTs on β2 agonists is only around 12 months, hence results cannot be extrapolated beyond that time frame. Mild, nonjarring physical activity such as swimming is encouraged.
Craniotabes is softening or thinning of the skull in infants and children, which may be normally present in newborns. It is seen mostly in the occipital and parietal bones. The bones are soft, and when pressure is applied they will collapse underneath it. When the pressure is relieved, the bones will usually snap back into place. Causes
Any condition that affects bone growth, most notably rickets (from vitamin D deficiency), marasmus,  syphilis, or thalassemia, can cause craniotabes if present during a time of rapid skull growth (most especially during gestation and infancy). It can be a "normal" feature in premature infants. It is the first sign in children and infants with rickets. Diagnosis
Physical examination

Management
Management of craniotabes depends on the cause. The majority of craniotabes occurs in term infants and can be a normal finding. Commonly, craniotabes results from the position of the head inside the uterus weeks prior to delivery. Calcium and Vitamin D levels should be obtained to rule out rickets, and in mothers who have prenatal labs concerning for T. pallidum infection, neonates should be evaluated for congenital syphilis. Etymology
The term (cranio- + tabes) is derived from the Latin words cranium for skull and tabes for wasting. References


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