QST Study: Predicting Treatment Response in Chronic Pancreatitis Using Quantitative Sensory Testing

Quantitative Sensory Testing (QST) is a novel investigative technique used in other pain conditions to evaluate patterns of chronic pain, and in this study will be used to elucidate pain patterns in patients with Chronic Pancreatitis (CP). QST uses a specific series of standardized stimulations to map the pain system. QST has the potential to change and improve the treatment paradigm for patients with CP and may eventually be able to predict response to invasive CP therapies.

In Chronic Pancreatitis (CP), clinical pain symptoms correlate poorly with pancreatic ductal morphology, response to endoscopic or surgical therapy is unpredictable, and the rationale for invasive therapies is often questioned. Quantitative sensory testing (QST) is a technique used to map the pain system based on the rationale that different neural pathways and networks can be explored using standardized stimulation and simultaneous recording of the evoked pain response by psychophysical and/or objective methods. In this study, the investigators aim to distinguish phenotypes characterized by segmental sensitization of the pancreatic viscerotome, and systemic sensitization with pathological central pain processing.

The investigators will perform QST on controls and CP subjects consisting of stimulation in several different dermatomes including pancreatic and control areas. All subjects will also answer standardized questionnaires assessing pain, depression, anxiety, and quality of life at baseline. Subjects undergoing endoscopic or surgical therapy will also undergo follow-up testing consisting of the same tests at 1, 3, and 6 months post-procedure for evaluation of changes in their pain profile.

Eligibility Criteria:
Inclusion Criteria:

1. Subjects with no pancreatic disease and no abdominal pain, or patients with a diagnosis of functional dyspepsia.

   * Subjects are 18 years or older in age
   * Subjects must be able to read and understand the study information.
   * Personally signed and dated informed consent document indicating that the subject has been informed of all pertinent aspects of the study.
   * Subject is willing and able to comply with the scheduled visits, questionnaires, treatment plan, and other study procedures.
2. Suspected CPs Inclusion Criteria

   * Subjects are 18 years or older in age
   * Subjects with a) Indeterminate CP (Cambridge 1 or 2 on CT scan or MRI/MRCP) who have abdominal pain without prior history of AP, or b) those with acute (AP) or recurrent acute pancreatitis (RAP) who have recovered from their attack(s) of AP, whose imaging studies are either normal or show changes consistent with Cambridge classification of 1 or 2, and they have ongoing abdominal pain. Both diabetic and non-diabetic subjects will be allowed to enter the study.
   * Subjects must be able to read and understand the study information.
   * Subjects must suffer from abdominal pain suspected to be pancreatic origin with an intensity above 3 on the visual analogue scale (VAS, where 0=no pain and 10= intolerable pain), and meet the criteria for chronic pain (pain ≥ 3 days per week for at least 3 months).
   * Personally signed and dated informed consent document indicating that the subject has been informed of all pertinent aspects of the study.
   * Subjects willing and able to comply with the scheduled visits, questionnaires, and other study procedures.
3. Definite Chronic Pancreatitis - Inclusion Criteria

   * Subjects are 18 years or older in age
   * Subjects will have a prior confirmed diagnosis of CP on CT scan or MRI/MRCP according to Cambridge Classification (grade 3 or 4). Both diabetic and non-diabetic subjects will be allowed to enter the study.
   * Subjects must be able to read and understand the study information.
   * Personally signed and dated informed consent document indicating that the subject has been informed of all pertinent aspects of the study.
   * Subjects willing and able to comply with the scheduled visits, questionnaires, and other study procedures.
4. Sphincter of Oddi Dysfunction (SOD) Type 1 or Type 2 Inclusion Criteria

   * Subjects are 18 years or older in age
   * Subjects have prior diagnosis of Type 1 or Type 2 Sphincter of Oddi Dysfunction (subjects with biliary pain accompanied by biochemical features of transient biliary tract obstruction including elevated transaminases, alkaline phosphatase, or conjugated bilirubin; may also be accompanied by biliary or pancreatic ductal dilation on imaging)
   * Subjects must be able to read and understand the study information.
   * Personally signed and dated informed consent document indicating that the subject has been informed of all pertinent aspects of the study.
   * Subjects willing and able to comply with the scheduled visits, questionnaires, and other study procedures.

Exclusion Criteria:

1. Subjects with no pancreatic disease and no abdominal pain, or patients with a diagnosis of functional dyspepsia.

   * Subjects with evidence or history of medical or surgical disease of importance for this study as judged by investigator.
   * Subjects suffering from painful conditions that make them unable to distinguish the pain associated with CP from chronic pain of other origins.
   * Subjects with known pregnancy at the time of enrolment.
   * Subjects who have previously undergone surgical intervention on their pancreas.
2. Suspected CPs Exclusion Criteria

   * Subjects with evidence or history of medical or surgical disease of importance for this study as judged by investigator.
   * Subjects suffering from painful conditions other than pancreatitis or SOD type 1 or 2 that make them unable to distinguish the pain associated with pancreatitis or SOD from chronic pain of other origins.
   * Subjects with known pregnancy at the time of enrolment.
   * Subjects who have previously undergone surgical intervention on their pancreas.
3. Definite Chronic Pancreatitis Exclusion Criteria

   * Subjects with evidence or history of medical or surgical disease of importance for this study as judged by investigator.
   * Subjects suffering from painful conditions other than pancreatitis or SOD type 1 or 2 that make them unable to distinguish the pain associated with pancreatitis or SOD from chronic pain of other origins.
   * Subjects with known pregnancy at the time of enrolment.
   * Subjects who have previously undergone surgical intervention on their pancreas.
4. Sphincter of Oddi Dysfunction (SOD) Type 1 or Type 2 Exclusion Criteria

   * Subjects with evidence or history of medical or surgical disease of importance for this study as judged by investigator.
   * Subjects suffering from painful conditions other than pancreatitis or SOD that make them unable to distinguish the pain associated with pancreatitis or SOD from chronic pain of other origins.
   * Subjects with known pregnancy at the time of enrolment.
   * Subjects who have previously undergone surgical intervention on their pancreas.