Muscular Dystrophy (MD) is well-known as a disease that progressively weakens muscles, leading to muscle spasms, difficulty walking, and eventually difficulty breathing. What many people don’t know is that MD is actually a group of diseases, each of which can have different effects on the human body. Doctors are still discovering and classifying new forms of MD.

This week the American Academy of Neurology (AAN) and the American Association of Neuromuscular & Electrodiagnostic Medicine (AANEM) issued guidelines meant to differentiate between MD disease types in preparation for genetic testing. The guidelines, published in this week’s Neurology, use symptoms, physical exams, lab tests, family history, and ethnicity to determine which genetic tests doctors should perform.

According to the guidelines’ lead author, Dr. Pushpa Narayanaswami, MD can often be difficult to diagnose. The guidelines should help doctors determine MD subtypes, leading to better treatments and avoiding unnecessary tests.

“Looking at a range of clinical signs and symptoms – such as which muscles are weak and if there is muscle wasting or enlargement, winging out of the shoulder blades, early signs of contracted limbs, rigidity of the neck or back, or heart or lung involvement – can help doctors determine which genetic test to order,” said Dr. Anthony Amato, senior author of the guidelines and a neurologist at Brigham and Women’s Hospital. “This in turn can shorten the time to diagnosis and start of treatment while helping avoid more extensive and expensive testing.”

According to the guidelines MD treatment should take place at facilities that specialize in the disease. No cure for MD yet exists, so the guidelines also suggest that MD patients inform their doctors of treatable symptoms such as shortness of breath or irregular heartbeat and that they seek out safe exercises.

“Before this publication, there were no care guidelines that covered both limb-girdle muscular dystrophy and distal MD and were based on the evidence,” said Julie Bolen, team lead on the guidelines and a member of the National Center on Birth Defects and Developmental Disabilities at the U.S. Centers for Disease Control and Prevention (CDC). “We hope that this guideline will fill that gap for both the people who live with these rare disorders and the health care professionals who treat them.”