Is ALS difficult to diagnose?

ALS is a serious disease, but one that is relatively easy to diagnose. For a neurologist, the symptoms and diagnostic criteria are very familiar. The external symptoms alone (muscle wasting, weakness, changes in reflexes, altered muscle tone ranging up to spasticity, fasciculations, reduced tongue mobility, weight loss, etc.) are enough to raise suspicion of ALS. The individual symptoms, taken on their own, are not conclusive. Only a typical combination of clinical features (e.g., the combination of muscle wasting with weakness and hyperreflexia) is characteristic of an ALS diagnosis.

A suspected diagnosis of ALS can be made based on a “simple” physical examination alone. This is followed by medical, laboratory, and radiological tests to rule out other neurological disorders (which, in some cases, can cause similar symptoms). These technical examinations (electromyography, electroneurography, cerebrospinal fluid analysis, and magnetic resonance imaging of the head or spine) are performed at a neurology clinic or during a hospital stay. Once these additional diagnostic tests are complete, an ALS diagnosis can be established beyond a doubt in the majority of patients.

Only in a minority of ALS patients is the diagnosis complicated and requires additional diagnostic tests (e.g., nerve and muscle biopsies). For the majority of ALS patients, a diagnosis of ALS can be made with just a few diagnostic steps (physical and neurological examination and electromyography). Some of those affected react with skepticism and doubt that such a serious diagnosis can be made using “the simplest” methods (“just physical examinations and a reflex hammer,” without “proper” diagnostic procedures). Overall, the challenge in diagnosing ALS lies not in the technical or equipment-related requirements, but rather in explaining the diagnosis and helping patients come to terms with it.