Both MS and fibromyalgia can be hard to diagnose, as they involve a range of nonspecific symptoms — such as pain and fatigue — which are common to various conditions.
To confirm a diagnosis of MS, a doctor will likely compare how lesions on MRI results change over time and how widespread they are on the body. A lab test of cerebral spinal fluid may show unusual features, such as high levels of certain proteins.
There is currently no diagnostic test that can confirm the presence of fibromyalgia. However, some research has shown that certain changes may be present in people with this condition.
Tests to rule out other conditions can help identify these conditions.