We prospectively enrolled 50 consecutive SSc patients and 60 healthy volunteers (HVs) as controls. Both groups underwent glucose breath test (GBT) to exclude small intestine bacterial overgrowth, lactulose hydrogen, and octanoic acid breath tests (LHBT and OBT) to measure OCTT and gastric emptying (GE), respectively, and manometry to assess esophageal motility.
Thirty-one (63 % ) SSc patients presented ineffective esophageal motility (IEM) compared with 3 HVs (5 % ; P<0.01), 37 (74 % ) had an abnormal OCTT compared with 4 HVs (7 % ; P <0.01), and 16 (32 % ) had an altered GE compared with 4 HVs (7 % ; P <0.01). The median OCTT and gastric t? were longer in SSc than in HVs (165 min vs. 101 min and 125 min vs. 78 min, respectively; P <0.01). A delayed GE was present in 12/37 (32 % ), whereas IEM in 27/37 (73 % ) SSc patients with prolonged OCTT. The prevalence of IEM increased in parallel with the prolongation of OCTT (31 % when OCTT<150 min, 73 % when OCTT¡Ý150 min, and up to 85 % when OCTT>180 min, P<0.01).
Abnormalities of both esophageal and small intestine motility are frequent in SSc patients and esophageal motility is altered in most cases with small bowel involvement. Delayed GE plays a limited role in prolonging OCTT. LHBT is a non-invasive, cheap, well-tolerated diagnostic tool that may be useful to estimate intestinal involvement and also to estimate a higher risk of esophageal hypomotility in SSc patients.