Neuropathic Gastroduodenal Disorders Can Be Diagnosed by Non-Invasive Body Surface Gastric Mapping: A Comparison With...

Antroduodenal manometry (ADM) is the gold standard for diagnosing myopathy and neuropathy in patients with upper gastrointestinal (GI) disorders. However, ADM is invasive and costly. Body surface gastric mapping (BSGM) has emerged as a non-invasive test to assess gastric function. This study evaluates the correlation between BSGM and ADM in children.

Clinically indicated ADM was performed using high-resolution water-perfused motility catheters, with simultaneous BSGM. Real-time symptoms were tracked using a validated symptom logging app at 15-min intervals, and Nausea Severity Scale (NSS) scores were recorded. Protocols involved a 2 h fast, provocative testing, a meal, and over 1 h of post-prandial recordings. ADM tracings were categorized into neuropathy, myopathy, post-prandial hypomotility, or normal. BSGM metrics included principal gastric frequency, BMI-adjusted amplitude, and Rhythm Index. Gastric emptying data were also evaluated.

Fifteen subjects were recruited (13 female; ages 10-19 years, BMI 20.6 ± 3.5 kg/m²). ADM results showed neuropathy (n = 4), myopathic CIPO (myopathy) (n = 1), post-prandial hypomotility (n = 4), and normal motility (n = 6). Patients with neuropathy had lower rhythm stability (0.16 ± 0.03 vs. 0.38 ± 0.17; p = 0.001), accompanied by higher nausea scores (8.2 ± 1.2 vs. 3.15 ± 2.9; p < 0.001) and bloating (7.3 ± 0.9 vs. 2.1 ± 2.0; p < 0.001). ADM neuropathy correlated completely with dysrhythmia on BSGM. Normal ADM were consistent with normal BSGM in 83.3% of cases. Delayed gastric emptying did not correlate with a neuropathic diagnosis.

Dysrhythmic BSGM phenotype reliably identified gastrointestinal neuropathy with identical results to ADM, with significant correlations to nausea and bloating severity. This study supports considering BSGM as an actionable biomarker when performing ADM is not feasible.