The Erasmus-Polyneuropathy Symptom Score as a screening tool for chronic axonal polyneuropathy
Aims: To validate the Erasmus-Polyneuropathy Symptom Score (E-PSS), a six-item symptom questionnaire, in a non-academic neurology out-patient setting and compare its performance with the questionnaire component of the Michigan Neuropathy Screening Instrument (MNSIq).
Methods: This cross-sectional observational study included 818 adults attending neurology outpatient clinics, for any reason of referral, at two non-academic Dutch hospitals. Participants completed the E-PSS and MNSIq, and the presence of chronic axonal polyneuropathy (PNP) was defined according to the treating physician’s diagnosis, based on clinical assessment and nerve conduction studies when indicated (as defined in the Dutch National Guideline on Polyneuropathy). Diagnostic discrimination was assessed using ROC curves and sensitivity analyses.
Results: PNP was diagnosed in 222 participants (27%), with diabetes being the established cause in 30 participants (14%), while 130 participants (59%) were classified as having idiopathic PNP. The E-PSS showed good discrimination (AUC 0.81, 95% CI 0.77–0.84), significantly outperforming the MNSIq (AUC 0.65, 95% CI 0.61–0.69). An E-PSS score ≥4 provided 73.9% sensitivity and 74.2% specificity. Tingling of the feet, numbness and a “cotton-wool” sensation were the most discriminating symptoms.
Conclusions: The authors conclude that E-PSS is a brief, easy-to-complete, symptom questionnaire with good discriminative ability for chronic axonal PNP in a routine neurology outpatient population and may facilitate the screening of patients for the presence PNP.
Comments: The current study evaluates the performance of E-PSS for the detection of chronic PNP of any cause in a non-selected general neurology out-patient clinic. The large number of included patients in a real-world setting is a clear strength. The E-PSS is developed with the aim of providing a simple and generalized questionnaire for PNP symptoms, applicable outside of specialized settings (six questions, total score 0-14). The E-PSS weighs questions based on both the type of symptom and its frequency (constant vs intermittent) based on previous validation (Hanewinckel R et al J Peripher Nerv Syst. 2019;24:235-241). The data presented in the current study shows a significantly clearer separation between patients with and without PNP of any cause when using E-PSS compared to MNSIq, which is of interest for the field of diabetic polyneuropathy (DPN).
DPN only accounted for 14% of the PNP cases, most probably because of the neurological out-patient setting. No subgroup analyses were performed. A similar setup in a primary care context, or an endocrinological out-patient clinic, including comparison to the MNSIq, would be of interest to define the value of E-PSS in DPN. As we know, early DPN detection may be difficult and asymptomatic patients may be missed with screening tools based on symptoms. However, this study strengthens the case for using a short symptom-based tool to screen patients for PNP and could be hypothesized to have value in non-specialized settings such as routine diabetes controls in primary care.
A potential limitation to the study is the overlap between the symptoms assessed by the E-PSS and those likely included in the clinical PNP assessment, which may introduce incorporation-related bias and potentially overestimate diagnostic discrimination. Hence, it would be of interest to see how E-PSS performs when requiring a confirmatory test for small- or large nerve fiber function/structure for PNP diagnosis.
Laura Linnea Määttä
Reference. Taams NE, Huijg M, Vermeij FH, Kuitwaard K, Hanewinckel R, de Beukelaar J, Reynolds EL, Callaghan BC, Ikram MA, van Doorn PA. The Erasmus-Polyneuropathy Symptom Score for the Screening of Chronic Axonal Polyneuropathy: A Validation Study. J Peripher Nerv Syst. 2026 Sep;31(3):e70143. doi: 10.1111/jns.70143. PMID: 42442712; PMCID: PMC13364287.
