Ischaemia of the small intestine in patients with systemic sclerosis: Raynaud's phenomenon or chronic vasculopathy?

We investigated duodenal and gastric mucosal blood flow by endoscopiclaser Doppler flowmetery (LDF) in ten patients with systemicsclerosis (SSc) and in ten healthy volunteers. In addition,we tested for the presence of small bowel bacterial overgrowthby jejunal aspiration. Jejunal aspiration and LDF were doneconsecutively, via a gastroscope, using a flexible catheterand laser Doppler probe. Following these procedures, two duodenalbiopsies were obtained for light and electron microscopy. Meanduodenal and gastric blood flow were significantly lower inpatients with SSc than in normal subjects (516 flux units vs.240, 521 vs. 202, both p < 0.001). There was no correlationbetween age and blood flow in patients or volunteers. Four ofthe ten patients had evidence of significant bacterial overgrowthon jejunal aspiration (>10⁵ colony-forming units/ml). Thesefindings support the hypothesis that within the small intestineof patients with SSc, factors independent of bacterial overgrowthmay be responsible for malabsorption. The observed reductionin small-intestine mucosal blood flow may play an importantcontributary role. Further studies are required to determinewhether this represents reversible or chronic progressive ischaemia,and its effect on nutrient absorption.