MS Allied Diseases and Conditions to Rule Out

The MS Society provides support and services to individuals with allied conditions including neuromyelitis optica spectrum disorder (NMOSD), transverse myelitis (TM) and acute disseminated encephalomyelitis (ADEM). Like MS, NMO, TM and ADEM are demyelinating conditions of the central nervous system. Although they share some of the same symptoms as MS, they are different conditions with distinct clinical features.

NMOSD is a rare autoimmune disorder of the central nervous system (CNS) where antibodies can damage the spinal cord and/or optic nerves during attacks. It is a demyelinating condition, meaning, it damages the protective myelin sheath around the nerve fibres. 

TM is a neurological disorder caused by inflammation of the spinal cord. It can occur in individuals of all ages and affects both genders. Symptoms of TM can include weakness of the legs and arms, pain, abnormal sensations (burning, prickling, tingling etc.) and bowel and bladder dysfunction. Most individuals will only have one TM attack although some may have a recurring attack. Transverse myelitis can also be the first symptom of MS or NMOSD.*

ADEM is a rare neurological condition characterized by a short-lived but widespread attack of inflammation in the central nervous system (brain, including optic nerve, and spinal cord) causing damage to the myelin. It is generally seen in children but can affect individuals of any age.

For more information about NMO or ADEM please visit our library.

Other Conditions to Rule Out

When MS is suspected, it is important for doctors to rule out other potential causes for the symptoms an individual is experiencing. Many symptoms suggestive of MS are also seen in other conditions.

Lyme disease

Lyme disease is an illness caused by the bacterium Borrelia burgdorferi, which can be spread through the bite of certain types of ticks. Lyme disease in humans can have serious symptoms, including neurological symptoms similar to those seen in MS, but can generally be treated with antibiotics. Lyme disease can cause rashes and joint symptoms unlike MS.

Neurological symptoms may include meningitis, encephalitis, Bell’s palsy, weakness, impaired language, fatigue and impaired memory. Brain MRI may or may not show lesions in the white matter. These lesions are usually non-specific, but sometimes may mimic MS lesions.

For more information about Lyme disease please visit the Public Health Agency of Canada.

Chronic Fatigue Syndrome (CFS)

Chronic Fatigue Syndrome is a disorder characterized by extreme fatigue without an underlying medical condition. There is no one test to diagnose CFS. Some CFS symptoms are similar to MS symptoms however CFS symptoms also include sore throat and swollen lymph nodes in the neck or armpit, which are not seen in MS.

Lupus (systemic lupus erythematosus)

Lupus is a chronic inflammatory disease where an individual’s immune system attacks its own tissues and organs. Inflammation caused by lupus can affect different body systems, including the joints, skin, kidneys, blood cells, brain, heart and lungs. Lupus can be difficult to diagnose because signs and symptoms are similar to those seen in other conditions however there are distinct symptoms that are not seen in MS such as skin rash, shortness of breath and fever.

This is not an extensive list; your doctor may need to rule out other conditions. It is possible to have MS and another condition but this does not mean that they are related or that one has caused the other.

*With information from NINDS