Symptoms and Diagnosis
The initial symptoms of ALS vary from person to person and may be very subtle. There are two general types of ALS onset: limb and bulbar. In limb-onset, the first symptoms will be in the arms or legs and start with weakness, tripping or stumbling or a reduction in fine manual dexterity. In bulbar-onset, the first symptoms will be difficulty in speaking or swallowing. As there are many diseases that cause these symptoms, an ALS diagnosis can be a long journey.
Every person with ALS has a different experience. Over time, people with ALS will experience difficulty moving, swallowing and speaking, and will eventually develop weakness in the respiratory muscles. When breathing becomes affected, people with ALS will need permanent ventilation support to assist with breathing.
Since ALS attacks only motor neurons, the sense of sight, touch, hearing, taste and smell are not affected. For many people, muscles of the eyes and bladder are generally not affected. Some people with ALS also have cognitive, emotional and behavioral symptoms. While ALS does not cause pain, pain is a symptom experienced by most people with ALS due to reduced mobility.
ALS is a difficult disease to diagnose. There is no existing test to establish the diagnosis of ALS. Physicians must rule out other diseases before a diagnosis can be established. ALS diagnosis should be performed by an experienced neurologist with expertise in neuromuscular diseases. Appropriate tests will includes many of the following:
- Electomyography (EMG) which detects electrical activity in the muscles
- Nerve conduction velocity (NCV) tests
- Blood and urine studies to eliminate other diseases such as Lyme disease, HIV, syphilis or heavy metal exposure
- Spinal tap
- X-rays, including magnetic resonance imaging (MRI)
- Myelogram of cervical spine
- Muscle and/or nerve biopsy
- A thorough neurological examination
There are several diseases that have similar symptoms to ALS, and most of these conditions are treatable. A person diagnosed with ALS should always seek a second opinion from an ALS expert - someone who diagnoses and treats many ALS patients and has training in this medical specialty. Click here to see local ALS Clinics or contact our Care Services Team.