Polyautoimmunity is a condition in which an individual has two or more autoimmune diseases that are not just coexisting but are linked by a shared underlying autoimmune process. It's different from simply having multiple unrelated conditions; in polyautoimmunity, the body's immune system mistakenly targets and attacks its own tissues in a cascade effect, leading to a cluster of autoimmune disorders.
For example, a person with Hashimoto's thyroiditis (an autoimmune disease affecting the thyroid) might also develop Type 1 diabetes (where the immune system attacks the pancreas) and celiac disease (which targets the small intestine). These conditions are all distinct, but they share a common thread of immune dysfunction, which leads to them appearing together.
In one study, researchers analyzed 1,083 patients from four autoimmune disease cohorts from a previously published series of patients with systemic lupus erythematosus, rheumatoid arthritis, multiple sclerosis, and systemic sclerosis. The cohorts investigated included 23 autoimmune diseases. A rheumatologist or neurologist evaluated patient demographics, clinical and laboratory data, physical examinations, interviews, and chart reviews. A systematic literature review was completed for all multiple autoimmune syndrome cases, with 226 cases from 142 articles. A clustering analysis found that autoimmune thyroid disease was the most common hierarchical disease.
The exact cause of polyautoimmunity is not fully understood, but it is believed to be a combination of genetic predisposition and environmental triggers. Certain genes can make an individual more susceptible to autoimmune diseases, and once the immune system is activated by a trigger (like an infection, stress, or diet), it may be more likely to develop multiple autoimmune conditions over time. The concept of polyautoimmunity highlights the interconnectedness of these diseases and suggests that treating one may not be enough to resolve the underlying immune issue. This is why I perform comprehensive testing on patients with autoimmune disease to look for key root causes, including gut problems (infections, microbiome imbalance, leaky gut), chronic infections, toxins, hormone imbalances, and others. Once the causes are identified, they can be treated in a holistic manner to balance the immune system.
Reference
Rojas-Villarraga, A., Amaya-Amaya, J., Rodriguez-Rodriguez, A., Mantilla, R. D., & Anaya, J.-M. (2012). Introducing polyautoimmunity: Secondary autoimmune diseases no longer exist. Autoimmune Diseases, 1–9. https://doi.org/10.1155/2012/254319
