Autoimmune gastritis as an unexpected cause of diarrhea in a young adult with type I diabetes: a case report

Type 1 diabetes mellitus (T1DM) is a lifelong diagnosis that involves immune-mediated damage of pancreatic beta cells and subsequent hyperglycemia, manifesting as: polyuria, polydipsia, polyphagia, and weight loss. Treatment of type 1 diabetes centers on insulin administration to replace or supplement the body's own insulin with the goal of achieving euglycemia and preventing or minimizing complications. Patients with T1DM are at risk for developing other autoimmune conditions, most commonly thyroid or celiac disease. A 20-year-old African American female with T1DM was referred by her endocrinologist to pediatric gastroenterology for 2 months of nocturnal, non-bloody diarrhea, left lower quadrant pain, and nausea; she was also being followed by neurology for complaints of lower extremity paresthesias and pain. The patient's initial lab-workup was remarkable for a low total Immunoglobulin A (IgA) level of