Autoimmune Diseases Triggered by E. coli Gastrointestinal Infections
E. coli gastrointestinal infections can trigger several autoimmune diseases, with the strongest evidence supporting reactive arthritis, systemic lupus erythematosus, Sjögren's syndrome, IgA nephropathy, and Henoch-Schönlein purpura. 1
Established Autoimmune Diseases Linked to E. coli Infections
Reactive arthritis - E. coli gastrointestinal infections are associated with a 48.7% increased risk of developing reactive arthritis compared to those without infection 1
Systemic lupus erythematosus (SLE) - E. coli infections increase the risk of developing SLE by 83.8%, with bacterial infections contributing to the exposure of nuclear autoantigens to the immune system 1, 2
Sjögren's syndrome - Patients with E. coli infection have a 100.2% higher risk of developing Sjögren's syndrome compared to non-infected individuals 1
IgA nephropathy - E. coli infection is associated with a 61.3% increased risk of developing IgA nephropathy 1
Henoch-Schönlein purpura - Children with E. coli infections have a 26.5% higher risk of developing this vasculitis 1
Mechanisms of Autoimmunity Induction
Molecular mimicry - Bacterial proteins from E. coli share structural similarities with human proteins, leading to cross-reactive immune responses 2, 3
Pro-inflammatory cell death - E. coli infections can trigger pyroptosis and NETosis, releasing nuclear autoantigens 2
Bacterial amyloid/DNA complexes - Curli amyloid fibers produced by E. coli form complexes with DNA that can trigger autoimmunity by acting as danger signals and molecular mimickers 2
Bacterial biofilms - E. coli biofilms contribute to chronic exposure to extracellular nuclear autoantigens, stimulating autoreactive immune responses 2
Conserved bacterial proteins - E. coli expresses proteins highly homologous to human autoantigens including proteinase 3, type II collagen, binding immunoglobulin protein, glucose-6-phosphate isomerase, α-enolase, and heterogeneous nuclear ribonuclear protein 3
Risk Factors for Developing Autoimmunity After E. coli Infection
Infection severity - Longer hospital stays for E. coli infection correlate with higher risk of autoimmune disease development 1
Recurrent infections - The risk of autoimmune disease increases with the frequency of E. coli infections 1
Pre-existing autoimmune conditions - The presence of other autoimmune diseases elevates the risk of developing additional autoimmune disorders after E. coli infection 1
Specific Autoimmune Conditions with Established Links
Hemolytic Uremic Syndrome (HUS)
- Shiga toxin-producing E. coli (STEC) is a well-established cause of HUS, particularly in children 4
- Antibiotics should be avoided in cases of STEC infection as they may increase the risk of HUS development 4, 5
Autoimmune Pancreatitis
- E. coli flagellin protein (FliC) has been identified as a potential trigger for autoimmune pancreatitis 6
- Repeated exposure to this bacterial protein can induce pancreatitis and higher titers of anti-lactoferrin and anti-carbonic anhydrase II antibodies 6
Diagnostic Considerations
- For suspected autoimmune diseases following E. coli infection, specific autoantibody testing should be performed based on clinical presentation 7
- In patients with gastrointestinal symptoms and subsequent joint pain, consider reactive arthritis and test for relevant autoantibodies 1
- For renal manifestations following E. coli infection, evaluate for IgA nephropathy with urinalysis and potentially renal biopsy 1
Clinical Implications and Management
- Monitor patients with severe or recurrent E. coli infections for signs of autoimmune diseases, particularly in the months following infection 1
- For Shiga toxin-producing E. coli infections, avoid antimicrobial therapy as it may increase the risk of HUS 4, 5
- Consider early rheumatology consultation for patients developing joint symptoms following E. coli gastroenteritis 1
- In pediatric patients with E. coli infections, maintain vigilance for development of Henoch-Schönlein purpura and IgA nephropathy 1