Characterizing Abdominal Pain in Patients with Gastroparesis

TITLE: CHARACTERIZING ABDOMINAL PAIN IN PATIENTS WITH GASTROPARESIS AUTHORS (LAST NAME, FIRST NAME): Vainer, Dylan1; Shahsavari, Dariush2; Parkman, Henry P.2 INSTITUTIONS (ALL): 1. Section of Gastroenterology, Lewis Katz School of Medicine at Temple University, Philadelphia, PA, United States. 2. Temple University Health System Inc, Philadelphia, PA, United States. ABSTRACT BODY: Introduction: Patients with gastroparesis (Gp) typically present with nausea, vomiting, and early satiety. Abdominal pain can be present in Gp. The cause of abdominal pain in patients with Gp is often unknown. In patients whose predominant symptom is abdominal pain, other causes of abdominal pain should be sought. Chronic pancreatitis and acute porphyria may be potential causes. Aims: 1) To characterize the abdominal pain in patients with diabetic (DM) and idiopathic Gp. 2) To determine if chronic pancreatitis and/or porphyria may explain the abdominal pain in a proportion of patients. Methods: Patients with Gp diagnosed by gastric emptying studies filled out Patient Assessment of Upper GI Symptoms (PAGI-SYM) questionnaire assessing their symptoms. Patients reporting abdominal pain also filled out questions to assess characteristics of pain and underwent testing for serum trypsin, amylase, lipase, urine porphyrins, and urine porphobilinogen (PBG). Results: Of 158 patients with Gp (140 (88.6%) women, average age 45.7 ± 15.8 years, BMI 26.9 ± 7.0), 86 (54.4%) patients reported abdominal pain as a symptom. The most common locations of pain were periumbilical (38.6%) and left upper quadrant (22.9%). 73.2% of patients with abdominal pain reported constant pain, with the majority (91.5%) having acute exacerbations of pain. The mean severity of constant pain was 2.94 ± 0.93 (scale from 0 = none to 4 = very severe), whereas the severity during acute exacerbations was 3.07 ± 0.82. 48.7% of patients reported radiation of pain, most commonly to the back (86%). Abdominal pain was most frequently exacerbated by eating (78.2%) and improved with use of pain medications (53.9%) and rest (52.6%). There was no difference in the prevalence of abdominal pain between DM and non-DM patients (43(53%) vs 107(56%); p = 0.807). DM and non-DM patients reported similar abdominal pain severity (chronic pain: 3.13 vs 2.89; p = 0.78, acute pain: 3.06 ± 0.87 vs 3.00 ± 0.80; p = 0.81). One patient with abdominal pain had a slight elevation in urine porphyrins (227.1 mg/L) and one had elevated urine PBG (4.1 mg/L). None of 45 (0%) patients with abdominal pain had low trypsin levels (\u3c 30 mg/L). No correlation was found between serum trypsin and severity of pain (r = 0.114; p = 0.457). Conclusion: Abdominal pain was present in 54% of patients with Gp and characterized by continuous pain with intermittent episodes of worsening pain. The pain was frequently exacerbated by eating and relieved by pain medications and rest. There were no significant differences in abdominal pain severity between DM and non-DM patients. Abnormal pancreatic enzyme and urine porphyrin levels were uncommon among Gp patients with abdominal pain and were not correlated with severity of symptoms. Thus, upper abdominal pain is frequent in patients with gastroparesis, but the cause remains largely unknown