AUTHOR=Siraj Elias S. , Homko Carol , Wilson Laura A. , May Patrick , Rao Ajay D. , Calles Jorge , Farrugia Gianrico , Hasler William L. , Koch Kenneth L. , Nguyen Linda , Snape William J. , Abell Thomas L. , Sarosiek Irene , McCallum Richard W. , Pasricha Pankaj J. , Clarke John , Tonascia James , Hamilton Frank , Parkman Henry P. 

TITLE=Islet Cell Associated Autoantibodies and C-Peptide Levels in Patients with Diabetes and Symptoms of Gastroparesis

JOURNAL=Frontiers in Endocrinology

VOLUME=Volume 9 - 2018

YEAR=2018

URL=https://www.frontiersin.org/journals/endocrinology/articles/10.3389/fendo.2018.00032

DOI=10.3389/fendo.2018.00032

ISSN=1664-2392

ABSTRACT=Individuals with diabetes are at increased risk for complications including gastroparesis.  Type 1 diabetes mellitus (T1DM) is an autoimmune disorder resulting in decreased beta-cell function. Glutamic acid decarboxylase-65 antibody (GADA) is the most commonly used test to assess autoimmunity while C-peptide level is used to assess beta cell function. Patients with type 2 diabetes mellitus (T2DM), who are GADA positive are labelled latent autoimmune diabetes in adults (LADA). Objective: To characterize patients with T1 and T2DM who have symptoms of gastroparesis using GADA and C-peptide levels and to look for association with the presence of gastroparesis and its symptom severity. Design:  113 T1DM and 90 T2DM patients with symptoms suggestive of gastroparesis were studied.  Symptom severity was assessed using Gastroparesis Cardinal Symptom Index (GCSI).  Serum samples were analyzed for GADA and C-peptide.  Results:  Delayed gastric emptying was present in 91 (81%) of T1DM and 60 (67%) of T2DM patients (p=0.04). GADA was present in 13% of T2DM subjects (10% in delayed gastric emptying and 20% in normal gastric emptying [p=0.2]). Gastric retention and GCSI scores were mostly similar in GADA positive and negative T2DM patients.  GADA was present in 45% of T1DM subjects (46% in delayed gastric emptying and 41% in normal gastric emptying [p=0.81]).  Low C-peptide levels were seen in 79% T1DM patients and 8% T2DM.  All 7 T2DM patients with low C-peptide were taking insulin compared to 52% of T2DM with normal C-peptide.  Conclusions:  GADA was present in 13% while low C-peptide was seen in 8% of our T2DM patients with symptoms of gastroparesis. Neither did correlate with degree of delayed gastric emptying or symptom severity.