Submitted to: Gastroenterology
Publication Type: Abstract only
Publication Acceptance Date: 3/1/2006
Publication Date: 4/1/2006
Citation: Robayo, C., Opekun, A.R., Quezada-Calvillo, R., Baker, S.S., Nichols, B.L. 2006. 13c-Sucrose breath test to differentiate congenital sucrase-isomaltase deficiency from pandisaccharidase deficiency [abstract]. Gastroenterology. 130(4 Suppl. 2):A319. Interpretive Summary:
Technical Abstract: Introduction: A substrate-paired breath test using 13C-sucrose (S) and 13C-glucose (G) has been developed to assess congenital sucrase-isomaltase deficiency (CSID). The aim was to determine if CSID could be detected without duodenal enzyme assay. Methods: Two patients (1F:1M, aged 1 & 15 yrs) with CSID (duodenal mucosa biopsy-proven), 3 patients with pandisaccharidase deficiency (P) (1F:2M, aged 10-15 yrs) and 5 normal patients (4F:1M, aged 3-15 yrs) were studied. All had mucosal enzyme activity determinations done. Uniformly labeled 13C-substrates (G & S; 20 mg. each, Isotec, Miamisberg, OH) were given in 10 gm unlabeled glucose oligomers (10%) vehicle after an overnight fast and reference sampling on 2 separate days. Serial 13CO2 breath enrichments (every 15 min * 6) were assayed using a 13CO2 infrared spectrophotometer (POCone®, Otsuka Electronics, Tokyo, Japan). A coefficient of glucose oxidation (CGO) was calculated for S breath enrichments to adjust for individual differences for each time-paired sample. Normal control patients were used to define CGO lower reference levels (LL) defined as mean-1 SD. Results: The CSID patients had S-CGO significantly below the LL, and the P patients had relatively normal S-CGO results above the LL. Duodenal S enzyme activity levels and S-CGO results closely correlated (R^2 0.72). Conclusions: The S/G substrate-paired breath test distinguished CSID patients from controls and differentiated CSID patients from the secondary forms of S deficiency. It appears that patients with low S-CGO could benefit from mucosal biopsy to identify additional enzyme deficiencies.