Perphial neuropathy or MS all my symptoms first pointed to be beginning stages of MS had a MRI done of the brain and it wasnt specific enough and have to have 2 more done but the neurologist said that he doesn't believe that it is MS and more like perphia

Testing can prove. If you have symptoms due to peripheral neuropathy, an EMG-nerve conduction test should be abnormal unless it is a small fiber neuropathy, which can be confirmed under the microscope. If you have MS, MRI of head and/or spinal cord could confirm diagnosis, but spinal fluid studies often can doubly confirm suspicions. Blood and urine studies can rule out other diseases which mimic MS.
Autonomic . Autonomic neuropathy can indeed give bowel and bladder problems along with peripheral neuropathy. There are tests that would be done by a urologist to evaluate the nature of your bladder dysfunction. A neurologist would do an electromyographic study to evaluate peripheral nerve function. If you are diabetic or prediabetic you may be developing neuropathy. While ms can cause bowel and bladder problems during the course of the disease, it doesn't usually cause peripheral nerve involvement. Your neurologist will probably request an EMG test along with autonomic testing.
To . To add to dr dyro's answer, ms can affect the spinal cord as well as the brain, so if a brain MRI was not conclusive but a spinal cord MRI was not done, ms has certainly not been excluded. As to whether autonomic neuropathy can be fatal, it is unusual but can happen, if low blood pressure affects the heart or brain, causing loss of consciousness which can then cause serious trauma depending on when it happens. If you have syncope and fall you could injure yourself substantially. Usually the various manifestations of peripheral or autonomic neuropathy can be treated symptomatically with some benefit but the underlying disease process is often not treatable with current knowledge and technology.