Diagnostic challenges in restless abdomen syndrome: A case report

Abstract

BACKGROUND

Restless abdomen is a rare phenotypic variant of restless legs syndrome (RLS), characterized by visceral discomfort and an urge to move localized to the abdominal region. Due to its atypical presentation, it is frequently misdiagnosed as a primary psychiatric or functional gastrointestinal disorder, leading to ineffective management.

CASE SUMMARY

We report the case of a 55-year-old female presenting with significant visceral discomfort and an irresistible urge to move localized to the abdomen, accompanied by severe anxiety and chronic insomnia. Initial treatment with standard antidepressant and hypnotic regimens for a suspected primary anxiety disorder proved ineffective. A comprehensive workup excluded underlying gastrointestinal pathologies. Diagnostic clarification was achieved via polysomnography, which revealed a significantly elevated periodic limb movement index (37.7 events/hour), providing objective neurophysiological support for an RLS diagnosis. Following the confirmation of an abdominal variant of RLS, monotherapy with pramipexole (0.25 mg/day) was initiated. The therapeutic response was rapid and robust: Within one week, abdominal restlessness resolved, and sleep quality normalized. Clinical remission was corroborated by marked reductions in the Hamilton Anxiety Rating Scale (from 20 to 3) and Hamilton Depression Rating Scale (from 10 to 3) scores.

CONCLUSION

Restless abdomen syndrome is easily misdiagnosed, making meticulous history taking, iron screening, and polysomnography paramount.

Keywords: Restless abdomen syndrome; Restless legs syndrome; Comorbidity of anxiety and insomnia; Dopaminergic therapy; Case report

Core Tip: Restless abdomen syndrome is an under-recognized variant of restless legs syndrome characterized by abdominal discomfort worsening at rest. This report describes a patient previously misdiagnosed with anxiety-induced insomnia. A novel finding was isolated hypotransferrinemia despite normal ferritin, suggesting a specific deficit in blood-brain barrier iron transport. The patient achieved complete remission with the dopamine agonist pramipexole. This report underscores the diagnostic value of the circadian symptom pattern and suggests that transferrin levels may offer mechanistic insights into restless legs syndrome variants, alerting clinicians to avoid misdiagnosing this treatable condition as a psychiatric disorder.