IVIG Reduces Symptom Severity for AGID

A new study indicates intravenous immun globulin (IVIG) therapy can reduce symptom severity for patients with autoimmune gastrointestinal dysmotility (AGID), also known as gastroparesis. AGID is a chronic digestive condition characterized by a delay in gastric emptying and is associated with many symptoms including early satiety, excessive fullness, nausea, vomiting and abdominal pain. While small, open-label studies of IVIG have demonstrated symptom improvement for patients with autoimmune markers, the new study evaluated how IVIG therapy affects symptom severity.

The retrospective case study included patients who were identified through medical chart review as having gastroparesis and seropositive autoimmune dysfunction identified through bloodwork. These markers included glutamic acid decarboxylase, neuronal voltage-gated calcium channel, acetylcholine receptor and neuronal voltage-gated potassium channel autoantibodies. All patients included in the study received at least 12 weeks of IVIG therapy. Before the treatment, the researchers collected the group’s Gastroparesis Cardinal Symptom Index (GCSI) scores to compare their post-treatment scores.

“Our study was limited to patients with seromarkers of autoimmune dysfunction associated with gastroparesis, as these are the only patients right now who have a chance of receiving insurance coverage for IVIG,” explained Madison Simons, PsyD, a gastrointestinal psychologist and the lead author of the study. “Even then, many patients are being denied coverage for this treatment. There is emerging evidence that even antibody-negative individuals may benefit from IVIG, but more evidence is needed to confirm this.”

The final sample included 27 patients (96.3 percent female; 81.5 percent white; mean age=39.0) with AGID. Just under half (44.4 percent) of the cohort had a per-oral pyloromyotomy (POP) prior to IVIG therapy. Gastric scintigraphy mean four-hour retention was 38.6 percent. The mean wireless motility capsule gastric emptying time was 677.0 minutes.

“Prior to receiving IVIG therapy, the patients indicated in their GCSI scores that early satiety was the most problematic symptom,” said Dr. Simons. “However, following treatment, the group’s mean GCSI scores significantly improved by more than 1.5 points, and two-thirds of the patients had GCSI scores that improved by at least 1 point after receiving IVIG therapy.”

Based on their findings, the researchers believes IVIG therapy should be considered for AGID treatment. Although the study showed significant improvement in symptoms for patients, the researchers suggests future randomized, placebo-controlled trials would provide more clarity on the effectiveness of IVIG in treating AGID.

According to Dr. Simons, the researchers hope their findings, in collaboration with other centers conducting similar research, may lead to funding opportunities for a randomized trial to better demonstrate the efficacy of this treatment. More work is also needed to predict who will most likely respond to IVIG treatment.