The NATURAL Study is a prospective, observational, pragmatic study of RNA biomarkers of infections to aid in the diagnosis of abdominal pain.

Summary of Research Study:

Hypothesis: A genomic-derived panel of 6 RNA biomarkers present in stabilized whole blood will provide diagnostic information about the presence of bacterial, biofilm, and viral infections in the abdomen. We hypothesize that biomarkers will be more than 90% sensitive with a high (>90%) negative predictive value for IAI.

Research Design: The project design is a prospective, pragmatic, observational study. The NATURAL Study will be sponsored by True Bearing Diagnostics, Inc., and performed at 5 or more academic medical centers. Patients with suspected intra-abdominal infections (IAIs), such as appendicitis, diverticulitis, acute cholecystitis, pancreatitis, peritonitis, pyelonephritis, and abscess are candidates for this study. This is a broad category of patients that are defined by the suspicion of an internal abdominal infection, usually involving some type of advanced imaging analysis, such as CT scan or ultrasound. All participants will be consented for this observational, minimal-risk study prior to venipuncture. Ultimately, The NATURAL Study will determine the positive agreement (~sensitivity) and negative agreement (~specificity) of the TruNAV RNA biomarkers in relation to the clinical diagnosis of the presence or absence of an IAI, based on CT scans and/or surgical confirmation, the current standard of care for diagnosis of IAI.

Objective: To validate a novel RNA fingerprint in ED patients with suspected IAIs.

The NATURAL Study is designed to determine the accuracy of novel RNA biomarkers for diagnosis of IAI in patients suspected of having IAI. Subgroup analysis will analyse RNA biomarker for multiple types of actual and suspected IAIs (appendicitis, diverticulitis, acute cholecystitis, pancreatitis, peritonitis, pyelonephritis, and abscess.)

Subjects: Approximately 1,000 ED patients presenting with abdominal pain that are candidates to receive CT or other confirmatory diagnostics will be enrolled.

The NATURAL Study Neutrophil Activation Test Using RNA Levels to aid in the diagnosis of abdominal pain.

A prospective, observational, pragmatic study of RNA biomarkers of infections to aid in the diagnosis of abdominal pain.

Summary of Research Study:

Hypothesis: A genomic-derived panel of 6 RNA biomarkers present in stabilized whole blood will provide diagnostic information about the presence of bacterial, biofilm, and viral infections in the abdomen. We hypothesize that biomarkers will be ~90% sensitive with a high (>90%) negative predictive value for IAI.

Research Design: The project design is a prospective, pragmatic, observational study. The NATURAL Study will be sponsored by True Bearing Diagnostics, Inc., and performed at 5 or more academic medical centers. Patients with suspected intra-abdominal infections (IAIs), such as appendicitis, diverticulitis, acute cholecystitis, pancreatitis, peritonitis, pyelonephritis, and abscess are candidates for this study. This is a broad category of patients that are defined by the suspicion of an internal abdominal infection, usually involving some type of advanced imaging analysis, such as CT scan or ultrasound. All participants will be consented for this observational, minimal-risk study prior to venipuncture. Ultimately, The NATURAL Study will determine the positive agreement (~sensitivity) and negative agreement (~specificity) of the TruNAV RNA biomarkers in relation to the clinical diagnosis of the presence or absence of an IAI, based on CT scans and/or surgical confirmation, the current standard of care for diagnosis of IAI.

Objective: To validate a novel RNA fingerprint in ED patients with suspected IAIs.

The NATURAL Study is designed to determine the accuracy of novel RNA biomarkers for diagnosis of IAI in patients suspected of having IAI. Subgroup analysis will analyze RNA biomarker for multiple types of actual and suspected IAIs (appendicitis, diverticulitis, acute cholecystitis, pancreatitis, peritonitis, pyelonephritis, and abscess.)

Subjects: Approximately 1,000 ED patients presenting with abdominal pain that are candidates to receive CT or other confirmatory diagnostics will be enrolled.

Inclusion Criteria:

Subjects must meet all of the inclusion criteria listed below to be eligible for the Study:

1. Age >6 years old
2. Abdominal pain of likely non-traumatic origin
3. Possible internal abdominal infection (IAI, see defined criteria)
4. Ability to provide informed consent/assent
5. Intent to order abdominal CT, ultrasound, endoscopy, or surgery

Exclusion Criteria:

Subjects with any one of the exclusion criteria listed below will not be eligible for treatment under this Study:

1. Any emergent situation where delay could be detrimental
2. Hemodynamically unstable (see age-appropriate criteria)
3. Prisoner
4. Inability to provide informed consent/assent
5. Non-English speaking

Patient Screening and Consent:

Prior to screening, each subject will be informed in detail about potential benefits of the results of TruNAV as well as of any risks and discomforts that are expected. The basic elements of informed consent as specified by International Conference on Harmonization (ICH) Good Clinical Practices (GCP) will be followed. Written consent will be obtained from each participant to be treated in the STUDY, by using the Investigational Review Board (IRB)-approved Informed Consent Form (ICF) prior to the conduct of any STUDY-related activity. Each subject will be given a copy of the signed and dated ICF. The participants will also be instructed that their participation is voluntary, and they are free to withdraw their consent and discontinue participation in the STUDY at any time without prejudice. In the case of persons younger than the age of consent (<18 years), parental consent and patient assent will be obtained. Patient assent is not needed for ages 6-7.

Sample Collection:

After appropriate screening and consent, the study tubes (4) marked with the study code ID, containing a special RNA preservative are drawn by venipuncture, or indwelling IV line if available.

Sample Preparation and Shipping The four (4) TruNAV tubes are collected: 4 tubes (Tempus) should all be shaken vigorously 10 times and then they rest at room temperature for 2 hours.

The Tempus tubes are shipped to the Sponsor in the packing provided via FedEx at the end of each day.

Clinical Data Extraction

1.1 Demographics, Medical History, and Clinical Assessment All of the data collection parameters are described in detail in the web-based electronic data collection (EDC) tool (iMednet). A general description is provided here for review and discussion.

1.2 Standard of Care Diagnostics As stated, no aspect of the clinical treatment of the patient should be altered because of this Study. However, the Sponsor is very interested in recording all of the tests and results performed.

1.2.1 Clinical Data

• Demographic data: race, sex, age, height, weight
• Blood pressure, heart rate, temperature 1.2.2 Laboratory Tests
• absolute lymphocyte count
• absolute neutrophil count
• neutrophil/lymphocyte ratio (NLR)
• %bands (if ordered)
• Serum lactate levels
• Creatinine
• Procalcitonin 1.2.3 Imaging
• Radiologist interpretation of CT/MR scan suggesting presence/absence of an internal infection. (non-invasive)
• Radiologist interpretation of ultrasound of the abdomen suggesting presence/absence of an internal infection. (non-invasive)
• Any type of upper or lower GI imaging by ingestion of contrast agents.
• Any type of camera-based 'pills' that are ingested for diagnostic purposes. 1.2.4 Surgery
• Any invasive surgical confirmation of a disorder by colonoscopy, endoscopy or laparotomy.

1.3 Standard of Care Treatment (if provided to patient) 1.3.1 Antibiotics, Antivirals, and Antifungals The specific types of these drugs, with doses and frequencies should be recorded.

1.3.2 Other Medication or Non-Surgical Treatment Other common medications that might be ordered should be recorded. This includes, but is not limited to: non-steroidal inflammatories (NSAIDs), steroids, such as prednisone, diuretics, laxatives, etc.

1.3.3 Surgical Treatment Surgery should be broadly interpreted to mean any invasive procedure. This could include a range of procedures from upper or lower GI imaging by endoscopy or laparoscopy or upper/lower GI contrast imaging.

1.4 Disposition or Resolution The final disposition of the patient at this visit is a specific endpoint of the Study. A typical range of dispositions is specified in the online collection tool: Admitted to floor, ICU, or surgery. Discharged. Death.

1.4.1 Clinical Assessment A particularly important endpoint of the Study is the final clinical assessment of a) the final confirmed diagnosis of an infectious disorder, ie appendicitis, and, b) of the clinically adjudicated likelihood of an infectious cause. These 2 dimensions are related, but can differ in important ways. For instance, a diagnosis of 'kidney stones' could have symptoms or lab results indicative of a related or unrelated infection, or, particularly in the case of non-obstructive stones that pass relatively easily, may have no infectious symptoms or lab results.

1.5 Long Term Follow Up Long term follow up is not required past the 30 day collection window. Only follow-up that is a normal part of the standard of care for the patient is required for the Study. No additional follow-up is needed.

Inclusion Criteria:

Age > 7 yr old Abdominal pain of likely non-traumatic origin Risk of intra-abdominal infection (see IAI signs) Ability to provide informed consent/assent Potential to order abdominal CT, ultrasound, endoscopy, or surgery for possible IAI

Exclusion Criteria:

Any situation where delay could be detrimental Hemodynamically unstable (see age-adjusted criteria) Prisoner or other involuntary detainee Inability to provide informed consent/assent

Patients presenting to a physician at an Emergency Department or Gastroenterology Clinic with a primary complaint of abdominal pain that the physician believes could have an infectious etiology.

IPD could include sequence data that could construed as identifiable. If stripped of any potential sequence or other personal data, the IPD will be disclosed.