title: Validation of a stable isotope gastric emptying test for normal, accelerated or delayed gastric emptying.
abstract: To validate a 13C-Spirulina platensis breath test for measurement of accelerated or delayed gastric emptying, we measured gastric emptying of egg containing 13C-S. platensis and 99mTc-sulphur colloid by breath 13 CO2 every 15 min over 3 h and scintigraphy every 15-30 min over 5 h in 57 healthy volunteers. Thirty-three received no treatment, 10 received erythromycin, and 14 atropine. A generalized linear regression model predicted half-emptying time by scintigraphy (t1/2S) from breath 13CO2 (t1/2B) data. Accuracy was assessed by standard deviation (SD) of differences between t1/2S and t1/2B and by receiver operating characteristic (ROC) curves. Regression models using breath samples at baseline, and 45, 90, 105 and 120 min, predicted t1/2B (mean +/- SD) at 118 +/- 59 min, similar to t1/2S (118 +/- 67 min). Correlation between t1/2B and t1/2S was significant (r=0.88; P < 0.0001). Differences between t1/2S and t1/2B were: 18-19.2 min for t1/2 < 70-150 min, and 68.3 min for t1/2 > 150 min. Breath test detected abnormal emptying with a sensitivity of 86% and specificity of 80%. Thus, the 13C-S. platensis test measures gastric emptying t1/2 for solids, which is accelerated or delayed to mimic a range of conditions from dumping syndrome to severe gastroparesis, with high sensitivity and specificity. Additional breath samples are needed to increase sensitivity in detecting accelerated gastric emptying.
authors.affiliation: Enteric Neuroscience Program, Gastroenterology Research Unit and Section of Biostatistics, Mayo Clinic and Mayo Foundation, Rochester, MN 55905, USA.
authors.forename: B E
authors.initials: BE
authors.lastname: Viramontes
authors.forename: D Y
authors.initials: DY
authors.lastname: Kim
authors.forename: M
authors.initials: M
authors.lastname: Camilleri
authors.forename: J S
authors.initials: JS
authors.lastname: Lee
authors.forename: D
authors.initials: D
authors.lastname: Stephens
authors.forename: D D
authors.initials: DD
authors.lastname: Burton
authors.forename: G M
authors.initials: GM
authors.lastname: Thomforde
authors.forename: P D
authors.initials: PD
authors.lastname: Klein
authors.forename: A R
authors.initials: AR
authors.lastname: Zinsmeister
mesh_terms: D000293:Adolescent; D000328:Adult; D000375:Aging / Q000502:physiology; D000465:Algorithms; D000900:Anti-Bacterial Agents / Q000009:adverse effects; D001285:Atropine / Q000009:adverse effects; D001426:Bacterial Proteins / Q000737:chemistry; D001944:Breath Tests; D002245:Carbon Dioxide / Q000032:analysis; D002247:Carbon Isotopes; D004917:Erythromycin / Q000009:adverse effects; D005260:Female; D005746:Gastric Emptying / Q000187:drug effects*; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D010276:Parasympatholytics / Q000009:adverse effects; D012727:Sex Characteristics; D053545:Spirulina
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D002247:Carbon Isotopes; D010276:Parasympatholytics; D002245:Carbon Dioxide; D004917:Erythromycin; D001285:Atropine