Fast Five Quiz: Can You Diagnose the Different Types of Spinal Muscular Atrophy?

Stephen L. Nelson, Jr, MD, PhD


December 06, 2018

Spinal muscular atrophy (SMA) is an autosomal-recessive disorder that affects lower motor neurons, causing progressive weakness and muscle wasting. SMA affects approximately 1 in 6000 to 1 in 10,000 live births; 1 in 50 people is a genetic carrier for the disease.

Although several types of SMA have been described, four main forms have been categorized on the basis of patient age of symptom onset and prognosis. Most cases of SMA are present at birth or in childhood, but some patients do not exhibit signs and symptoms until they are in their mid-30s.

Are you familiar with the types, presentation, workup, and diagnosis of SMA? Test your knowledge with our short quiz.


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