<<Disclaimer: Verify this information before applying it to your situation.>> I would just like to add an update on sorbitol H2 breath testing for celiac disease. Here is an interesting recent letter by Antonio Tursi commenting on the usefulness of the sorbitol H2 test: Seronegative coeliac disease - a clinical challenge Antonio Tursi (26 April 2005) http://bmj.bmjjournals.com/cgi/eletters/330/7494/775 ---------- Perhaps one reason why more doctors don't make use of the sorbitol H2 test is that they don't want patients sitting around in their offices for over 4 hours while getting the test. In answer to that, in case you missed my posting over the July 4th weekend, I refer you to the following: Do-It-Yourself Sorbitol H2 Testing - Part 1 & 2 http://maelstrom.stjohns.edu/CGI/wa.exe?A2=ind0507a&L=celiac&P=1874 http://maelstrom.stjohns.edu/CGI/wa.exe?A2=ind0507a&L=celiac&P=1748 In those posts, I listed a benchtop model, and 2 portable, handheld breath H2 analyzers. Here is one more portable, handheld analyzer I missed selling for $2,500. I note in this website that there is no mention of a need for periodic calibration, nor do they sell H2 calibration gas. I would check with them as to whether calibration is needed: HBT Sleuth, Breathe E-Z Systems, Inc. http://www.testbreath.com/products/hbt.htm * * * *Support summarization of posts, reply to the SENDER not the CELIAC List*