Adult Pilot Study for Reference Ranges and Optimal Cut-offs for the Sucrose Challenge Test and Sucrose Breath Test

Adult Pilot Study to Establish the Reference Ranges and Optimal Cut-offs for Oral 50g Sucrose Challenge Test & 13C-Sucrose Breath Test for CSID Cases (Previously Diagnosed Sucraid Responders) & Controls (GI Asymptomatic Healthy Volunteers)

An adult pilot study to establish the normal reference range and optimal cutoffs for the oral 50g Sucrose Challenge Test (SCT) and the 50g 13C-Sucrose Breath Test (CBT) for patients with CSID and healthy controls. This study will enroll 120 healthy controls and 50 CSID patients. No study drug will be administered during this study.

In an effort to mimic the real-world diagnostic setting for these tests, this study will be conducted virtually using a central site with telemedicine capabilities and electronic data capture software to collect data in real time via a mobile app. Subject will complete 3 visits within 21 days. Eligible subjects will undergo the following tests:

1. 50g 13C-Sucrose Breath Test (CBT)
2. Sucrose Intolerance Hydrogen Methane Breath Test (HBT)
3. Sucrose Challenge Test (SCT)
4. Buccal swab for CSID Genetic Testing (GT)

The primary aim is to establish the reference/normal ranges and optimal cutoff values for the SCT and CBT.

Inclusion Criteria:

• Subject must provide informed consent prior to any study procedures being performed.
• Subject is a U.S. resident, and speaks and understands English
• Subject is male or female, ≥ 18 years old.
• CSID Cases must have been on Sucraid for at the last 12 months.
• Healthy Volunteers do not have a CSID diagnosis or other chronic gastrointestinal conditions.
• Subject must have their own Android or Apple device to access the mobile patient app.

Exclusion Criteria:

• Females who are lactating or pregnant.
• Subjects with allergy to sucrose.
• Subjects with causes of abdominal pain or altered bowel habits other than symptoms -related to CSID (in CSID group) such as SIBO, IBD, celiac disease, pancreatitis, or -gastrointestinal bleeding.
• Diabetes mellitus.
• Use of systemic antibiotics, had a barium study, colonoscopy, unexplained runny diarrhea, or similar within 14 days prior to informed consent. Potential subjects can be re-screened once they meet this criterion.
• Recent febrile illness.
• Subject has major physical or psychiatric illness within the last 6 months that in the opinion of the investigator would affect the subject's ability to complete the trial.