Evaluation and Management of Functional Neurological Symptoms in Patients with Multiple Sclerosis

Background: Functional or conversion symptoms, classified in DSM-5 under Somatic Symptom Disorder (SSD), are highly prevalent in patients with confirmed neurological conditions. Psychiatric comorbidity is common in multiple sclerosis. In addition to depression and other conditions, anecdotal evidence and input from seasoned MS specialists suggest that functional neurological symptoms and SSD may also be highly prevalent in MS but the level of evidence and guidelines in this area are very limited.

 In this context patients with multiple sclerosis frequently present with somatic or neurological symptoms that raise the question of a functional etiology; the ensuing evaluation is challenging and there is little to guide the clinician in the active management of a case. 

Objectives: The goals of this study were to review the current state of scientific knowledge regarding the topic of functional symptoms in patients with established MS and to summarize our findings into a set of guidelines that clinicians can use in their assessment and management of these patients.

Methods: We conducted a PubMed search combining multiple sclerosis with the following keywords: somatization, conversion disorder, pseudo-relapse, pseudo-flare, factitious, Munchausen, and summarized the current literature.

We reported representative cases of patients with established MS and comorbid functional neurological disorders gathered from the collective experience of a multidisciplinary group of MS specialists. The cases demonstrate four different presentations of functional symptoms in MS: 1) classic conversion disorder with sensory and motor symptoms, 2) anxiety and somatic hypervigilance with multiple somatic symptoms, 3) pain disorder, 4) cogniform presentation. We convened the approach of these MS experts into a set of guidelines to be used in assessment and management of this patient population.

Results: The level of scientific evidence is limited to case reports and case series. There is a lack of evidence-based guidelines and a need for increased awareness about this problem. Patients may be misdiagnosed as having MS relapses and receive unnecessary medical treatments that can cause iatrogenic complications, while their underlying psychiatric illness may go untreated. The assessment and management of these patients should be interdisciplinary whenever possible. Aspects of history, mental status, and neurological exam may aid in differential diagnosis. Brain imaging may aid in some cases, but has limitations. Education of patients and their engagement in this diagnostic and therapeutic process are an essential component.

Conclusions: Functional symptoms are common in patients with clinically definite multiple sclerosis; we propose initial guidelines to aid in evaluation and management of these symptoms. Further research is needed to understand prevalence, clinical presentation, and best approaches to treat functional disorders in MS patients.