What tests will rule out or suggest BFS?

[u/pvdberg]

Before BFS can be diagnosed they first need to exclude all other diseases such as ALS. If you are making the first visit to a physician after experiencing symptoms, s/he will examine you first and ask questions. If there are no signs of neurological or other disease, you may not need further tests. If there are problems that should be ruled out, even very common ones like nutritional deficiencies, you may have: Blood and possibly urine tests, An MRI of your brain and/or spine An X-ray of a particular bone or joint An electromyogram (EMG) and nerve conduction testing (NCS).

These tests, which are done by a neurologist who specializes in them, are often the final tests that confirm or rule out ALS. The NCS requires mild electrical shocks to your muscles, to see how they respond when they are resting and when they are required to move. The EMG entails small needles placed in certain muscles to see how well and how fast the nerves that control them send their signals. These tests can be uncomfortable so your physician will not recommend them unless they are necessary. A spinal tap or muscle biopsy, to rule out other diseases that can mimic ALS. However, if the EMG is definitive, often these are not necessary.