Comparison of near infrared reflectance analysis of fecal fat, nitrogen and water with conventional methods, and fecal energy content

Objectives: To evaluate Near-Infrared Analysis (NIRA) method for determining fecal fat, water and nitrogen. Design and methods: The results of fecal fat, water and nitrogen by NIRA were compared with results of van de Kamer and Acid Steatocrit (AS), Dumas and vacuum drying methods for fat, nitrogen and water respectively. Results of fat determining methods were also compared with total fecal energy as obtained by bomb calorimeter. Results: NIRA results correlated significantly (p< 0.001) with standard methods for nitrogen (r = 0.79), fat (r = 0.84 and R = 0.88 for van de Kamer and AS respectively) and water (r = 0.91). The limits of agreement for nitrogen and fat results were too wide for the methods to be used interchangeably. The fecal fat results correlated significantly (p< 0.001) with fecal energy results. Conclusion: NIRA may be valuable for monitoring malabsorption but the diagnostic value remains to be determined.