Using atypical symptoms and red flags to identify non-demyelinating disease

Area of Science:

• Neurology
• Clinical Diagnostics

Background:

• Red flags and atypical symptoms may suggest alternative diagnoses in suspected multiple sclerosis (MS) or clinically isolated syndrome (CIS).
• The diagnostic utility of these indicators has not been previously assessed.

Purpose of the Study:

• To determine the predictive value of red flags and symptom typicality/atypicality in diagnosing MS/CIS.
• To evaluate the diagnostic utility of clinical presentation features for MS/CIS.

Main Methods:

• Assessed patients referred for suspected MS over three years.
• Evaluated symptom typicality and red flags against final diagnoses.
• Determined inter-rater agreement between trainee and consultant neurologists on clinical presentation typicality.

Main Results:

• Of 244 referred patients, 119 (49%) had MS/CIS. Atypical symptoms (n=96) were associated with a high rate of non-MS/CIS diagnosis (84%).
• Atypical symptoms demonstrated 84% sensitivity, 90% specificity, and a positive likelihood ratio (PLR) of 8.4 for excluding MS/CIS.
• Red flags showed 47% sensitivity, 88% specificity, and a PLR of 3.9 for excluding MS/CIS. Inter-rater agreement was 73%.

Conclusions:

• Atypical presenting symptoms are more sensitive, specific, and possess a higher PLR than red flags for refuting a diagnosis of MS/CIS.
• Symptom presentation is a valuable tool in differentiating MS/CIS from other neurological conditions.