5 Steps of SMA Diagnosis

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by Wendy Henderson |

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Spinal muscular atrophy (SMA) is a rare genetic disorder that affects around one in 10,000 babies. The severity of the disease varies, but children with SMA are usually unable to walk and after time, muscle degeneration can affect their ability to sit, swallow and breathe without assistance. Diagnosis of the disease is usually a straightforward process involving these simple steps:


1. Failing to Meet Milestones

Usually, the parents will be the first to realize something is wrong when their infant fails to meet milestones such as turning over, crawling, etc. They will then speak to their doctor about their concerns.

Read about five frequently asked questions about spinal muscular atrophy.

2. Physical Exam and Family’s Medical History

The doctor will likely perform a physical exam and take down details of the family’s medical history.

Read about five experimental therapies for SMA you might find interesting


3. Creatine Kinase Test

The doctor might also run a test for creatine kinase (CK), an enzyme that can leak out of deteriorating muscles. Elevated levels of CK could point to a number of neuromuscular diseases.

Understand more about spinal muscular atrophy and poor muscle tone. 


4. Blood Test

A blood test is the most accurate way to diagnose SMA; it will determine if the patient has the faulty SMN1 and SMN2 genes which cause the disease.

This video explains more about the faulty SMN2 gene.


5. Further Tests

Further tests are usually carried out to determine the type (SMA types run from type I to type IV, with type I being the most severe). These may include electromyography (EMG) to discover the health of the muscles and motor neurons, nerve conductor velocity tests, and occasionally muscle biopsies in cases where it is not possible to carry out genetic tests. Read more about diagnosing SMA.

Find out more about the four different types of SMA. 

SMA News Today is strictly a news and information website about the disease. It does not provide medical advice, diagnosis or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or another qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.