Approach to the Critical Patient

Immediate priorities

Airway and breathing threats

Rapidly deteriorating neurologic status

Pseudo-relapse versus true relapse — first branch point

Monitoring and targets

Monitoring bundle

Escalation and consult triggers

Immediate neurology consultation

ICU-level care indications

History

Onset and symptom characterization

Relapse definition

Core symptoms

Visual symptoms

Motor and sensory symptoms

Cerebellar and brainstem symptoms

Autonomic and bladder symptoms

Triggers and precipitants

Infection as relapse trigger

Heat exposure (Uhthoff phenomenon)

Stressful life events (RR 2.2 within 4 weeks of major stress)

DMT nonadherence or discontinuation

Alarm features in history

Features suggesting NMOSD rather than MS

Features suggesting PML

Features suggesting alternative diagnosis

Baseline and prior disease history

MS subtype and disease course

Prior relapse pattern

Physical Exam

Vital signs

Temperature assessment

Neurologic examination

Visual system

Cranial nerve examination

Motor system

Sensory system

Cerebellar and gait examination

Bladder and sacral function

Comparison to baseline

Documented prior neurologic examination

Differential Diagnosis

Pseudo-relapse

Pseudo-relapse (most common mimic of true relapse)

Demyelinating mimics

NMOSD (neuromyelitis optica spectrum disorder)

MOGAD (myelin oligodendrocyte glycoprotein antibody disease)

ADEM (acute disseminated encephalomyelitis)

Vascular

Ischemic stroke or TIA

Transverse myelitis (non-MS)

Infectious

PML (progressive multifocal leukoencephalopathy)

CNS infection (meningitis, encephalitis, brain abscess)

Structural and metabolic

Cervical spondylotic myelopathy

Vitamin B12 or copper deficiency (subacute combined degeneration)

CNS lymphoma or tumefactive MS

Laboratory Tests

First-line workup

Rule out pseudo-relapse

Diagnostic uncertainty workup

CSF analysis (when diagnosis uncertain or atypical presentation)

Antibody serology

Monitoring and ancillary labs

Vitamin D level (25-OH vitamin D)

DMT-specific monitoring labs

Emerging biomarkers

Diagnostic Tests

Scoring Systems

EDSS (Expanded Disability Status Scale)

MS Functional Composite (MSFC)

McDonald Criteria (2017, updated 2024)

MRI

MRI brain without and with gadolinium

MRI spinal cord (cervical and thoracic) with gadolinium

MRI for PML exclusion

CT

CT head (non-contrast)

Ultrasound

Bladder ultrasound

Optic nerve ultrasound

General utility

Disposition

Admission criteria

Indications for inpatient admission

Observation indications

Moderate relapse with IV steroid treatment

Discharge criteria

Mild to moderate relapse with preserved function

Specialist consultation triggers

Neurology (all confirmed or suspected relapses)

Treatment

Acute relapse treatment — steroids

IV methylprednisolone (first-line)

Steroid-refractory relapse

Plasma exchange (therapeutic plasma exchange, TPE)

Disease-modifying therapy review

Breakthrough relapse on current DMT

DMT adverse effect management

Supportive care

Bladder management

Spasticity management

Neuropathic pain

Fatigue

Depression and anxiety

Special Populations

Pregnancy

Relapse risk during pregnancy

Treatment of relapse in pregnancy

DMT management during pregnancy

Geriatric

Age-related diagnostic challenges

Treatment modifications in elderly

Pediatrics

Pediatric MS characteristics

Diagnostic considerations in pediatrics

Treatment in pediatrics

Background

Epidemiology

Global MS prevalence and incidence

Relapse epidemiology

Disability outcomes

Pathophysiology

Immune-mediated demyelination

Relapse mechanism

Lesion distribution

Remyelination

Therapeutic Considerations

Steroid mechanism of action

Plasma exchange mechanism

Disease-modifying therapy classes

Vitamin D and lifestyle

Patient Discharge Instructions

copy discharge instructions

What is an MS relapse?

Your steroid treatment

Activity and heat avoidance

Follow-up

Return to the emergency department if you experience

References

Guidelines and key sources

McGinley MP, Goldschmidt CH, Rae-Grant AD — Diagnosis and Treatment of Multiple Sclerosis: A Review

Gavoille A, Rollot F, Casey R, et al — Acute Clinical Events Identified as Relapses With Stable MRI in Multiple Sclerosis

Le Page E, Veillard D, Laplaud DA, et al — COPOUSEP Randomized Controlled Trial

Wattjes MP, Ciccarelli O, Reich DS, et al — 2021 MAGNIMS-CMSC-NAIMS Consensus MRI Recommendations

Solomon AJ, Arrambide G, Brownlee WJ, et al — Differential Diagnosis of Suspected MS

Bunganic R, Blahutova S, Revendova K, et al — Therapeutic Plasma Exchange in MS Aggressive Relapse

Pfeuffer S, Rolfes L, Bormann E, et al — Comparing Plasma Exchange to Escalated Methylprednisolone

Jakimovski D, Bittner S, Zivadinov R, et al — Multiple Sclerosis

Expert Panel on Neurologic Imaging — ACR Appropriateness Criteria: Demyelinating Diseases

Fadda G, Armangue T, Hacohen Y, Chitnis T, Banwell B — Paediatric MS and Antibody-Associated Demyelination

Pakpoor J, Saylor D, Izbudak I, et al — Emergency Department MRI Scanning of MS Patients

Pelletier J, Sugar D, Koyfman A, Long B — Multiple Sclerosis: Emergency Medicine-Focused Narrative Review

Bar-Or A, Li R — Cellular Immunology of Relapsing MS

Beiki O, Frumento P, Bottai M, Manouchehrinia A, Hillert J — Changes in MS Disability Milestone Rates