Treating chronic diarrhea: A systematic review on Immunoproliferative Small Intestinal Disease (IPSID)

Immunoproliferative Small Intestinal Disease (IPSID) is a disease characterized by extra-nodal marginal zone B-cell lymphoma with villous atrophy in the small intestine, causing chronic intermittent non-bloody diarrhea. Although originally associated with the Mediterranean region, this disease is present in many countries worldwide and may have been underreported due to its complicated diagnosis and scarce scientific literature, especially in regards to treatment. This study aims to review IPSID clinical features, therapeutic options, and treatment outcomes to help physicians identify and treat IPSID. Using PRISMA guidelines, a systematic review of articles was conducted on PubMed database with search terms including IPSID, therapy, treatment, and outcomes. Inclusion and exclusion criteria were used to select 33 English language articles published from the year 2000-2020 that included relevant clinical information about IPSID treatment. Data were extracted independently by at least two authors to reduce the introduction of potential bias. There were 22 case reports, 7 reviews, 1 research article, 1 prospective study, 1 letter to the editor and 1 memoriam in which 76 patients were identified. Epidemiological analysis showed a mean patient age of 32 years old, 2.4:1 mal to female ratio and heterogeneous ethnicities, with 16 Europeans (43.2%) and 12 Asians (32.4%). Chief symptoms included chronic diarrhea (53/76, 69.7%), weight loss (49/76, 64.4%), malabsorption (38/76, 50%), abdominal pain (32/76, 42.1%), and finger clubbing (24/76, 31.6%). Patients stratified into the early disease stage (Galian A) were treated with tetracycline antibiotics, corticosteroids, and non-pharmacological supplements with mostly with complete or partial remission. Late stages (Galian B or C), were treated mostly with anthracycline-based chemotherapy, and occasionally surgery, radiotherapy, or rituximab. This work offers a targeted approach to diagnosing and treating IPSID to aid physicians and serve as a treatment guideline recommendation for future public policies and clinical studies.