Phenotypical Characterization of Gastroenterological and Metabolic Manifestations in Patients With Williams-Beuren Syndrome

Gastrointestinal (GI) symptoms are common in patients with Williams–Beuren syndrome (WBS), but their prevalence and possible causes are not yet fully known. This study assessed GI symptoms' prevalence and their possible origin by performing a predefined set of tests in adult WBS patients. Laboratory tests and a questionnaire were administered to assess GI symptoms and dietary habits. All the patients underwent the urea breath test, H2-lactose and H2-glucose breath tests, and intestinal ultrasound (IUS) and vibration-controlled transient elastography for liver stiffness measurement (LSM) and controlled attenuation parameter (CAP, dB/m). Thirty-one patients were enrolled (72% of the whole cohort, 17 males, median age 32 years). Gastroesophageal reflux disease (GERD) symptoms were reported in 29% of the patients, abdominal pain in 26%, and altered bowel habits in 48%. Pathologic signs at (IUS) were present in 60% of the cases. Prevalence was 0.26 (95% CI 0.12–0.44) for Helicobacter pylori infection and 0.61 (95% CI 0.42–0.78) for lactose intolerance. LSM was > 6 kPa (in the range of a fibrosis score > F1) in three patients, and CAP values were > 268 dB/m (corresponding to a steatosis score > S2, e.g., moderate steatosis) in nine. The presence of altered bowel habits was significantly related to chronic abdominal pain (OR 13.1, p = 0.03). Increased BMI (> 28 kg/m2) (OR 10.8, p = 0.04) was associated with the presence of moderate–severe hepatic steatosis. After specific treatment and dietary counseling, most patients reported resolution/improvement of symptoms, whereas a few retained/developed symptoms during follow-up. Chronic abdominal pain, GERD symptoms, and unbalanced metabolic parameters were common in our WBS patients, together with an increased prevalence of lactose intolerance/colonic diverticula. Specific counseling and treatment improved symptoms for most patients.