Symptoms in MS can appear or become more pronounced when the MS is active and may lessen or disappear when it is quiet. Often symptoms can feel - and may be - worse when a person is tired, under stress (upset, worried, anxious), or suffering from some common and totally unrelated condition such as a bad cold or influenza, an infection, or injury. These fluctuations do not necessarily mean that the MS is getting worse; only that everyone has good days and bad days, and that the influence of other, unrelated, conditions is real and should not be ignored.
The most common presentation of MS is the clinically isolated syndrome (CIS). In CIS, a patient has an attack suggestive of demyelination, but does not fulfill the criteria for multiple sclerosis. Only 30 to 70% of persons experiencing CIS later develop MS. The disease usually presents with sensorial (46% of cases), visual (33%), cerebellar (30%) and motor (26%) symptoms. Many rare initial symptoms have also been reported, including aphasia, psychosis and epilepsy.
Patients first seeking medical attention commonly present with multiple symptoms. The initial signs and symptoms of MS are often transient, mild, and self-limited. These signs and symptoms often do not prompt a person to seek medical attention and are sometimes identified only retrospectively once the diagnosis of MS has been made. Cases of MS are sometimes incidentally identified during neurological examinations performed for other causes. Such cases are referred to as subclinical MS
Nystagmus, characterized by involuntary eye movements, is one of many symptoms that can appear with MS.
The person with MS can suffer almost any neurological symptom or sign, including changes in sensation (hypoesthesia and paraesthesia), muscle weakness, muscle spasms, or difficulty in moving; difficulties with coordination and balance (ataxia); problems in speech (dysarthria) or swallowing (dysphagia), visual problems (nystagmus, optic neuritis, or diplopia), fatigue, acute or chronic pain, and bladder and bowel difficulties. Cognitive impairment of varying degrees and emotional symptoms of depression or unstable mood are also common. The main clinical measure of disability progression and symptom severity is the Expanded Disability Status Scale or EDSS.Multiple sclerosis relapses are often unpredictable, occurring without warning and without obvious inciting factors. Some attacks, however, are preceded by common triggers. Relapses occur more frequently during spring and summer. Infections such as the common cold, influenza, or gastroenteritis increase the risk of relapse. Stress may also trigger an attack. Pregnancy may affect susceptibility to relapse, offering protection during the last trimester, for instance. During the first few months after delivery, however, the risk of relapse is increased. Overall, pregnancy does not seem to influence long-term disability. Many potential triggers have been examined and found not to influence MS relapse rates. There is no evidence that vaccination for influenza, hepatitis B, varicella, tetanus, or tuberculosis increases risk of relapse. Physical trauma does not trigger relapses. Exposure to higher than usual ambient temperatures can exacerbate extant symptoms, an effect known as Uhthoff's phenomenon. Uhthoff's phenomenon is not, however, an established relapse trigger.
