Patients with primary immune thrombocytopenia (ITP) appear to have a greater risk of developing systemic lupus erythematosus (SLE) than the general population, with women having a particularly high risk, according to a recently published meta-analysis in Autoimmunity Reviews.
The pathogenic mechanisms of ITP, characterized by an abnormal T-cell response that leads to B-cell differentiation and the production of antiplatelet antibodies, overlap with those involved in SLE. Furthermore, thrombocytopenia is a common finding in patients with SLE and is one of the most common initial presentations of the disease.
Read more about ITP comorbidities
Thus far, several studies have found a direct correlation between ITP and an increased risk of developing SLE. Therefore, the authors performed an extensive systematic literature review and meta-analysis to assess the development of SLE in patients with ITP and its associated factors.
“Studies suggest that [antinuclear antibody (ANA)] positive ITP may represent a distinct subgroup who are at risk of developing systemic autoimmune diseases,” the authors wrote.
The researchers used the PubMed, Web of Science, and Cochrane Library databases to search for the keywords “immune thrombocytopenia,” “immune thrombocytopenic purpura,” and “antinuclear antibody,” among others. The study included papers that studied the correlation between SLE and ITP in patients with ITP diagnosed according to the American College of Rheumatology criteria for SLE diagnosis. All findings were individually reviewed by two of the authors.
After an extensive review of 3316 articles, 26 articles were included in the meta-analysis, of which 23 included ANA levels. The selected studies involved over 14,000 patients with ITP.
The results revealed that the overall random-effects pooled prevalence of SLE was approximately 2%, with 224 patients with ITP developing SLE, 87% of which were women. ANA was present in over 17% of patients, significantly increasing the risk of developing SLE.
“ITP patients with positive ANA titers represent a distinct high-risk group requiring a close follow-up. Furthermore, the risk of developing SLE in ITP patients seems to increase with time,” the authors concluded.
Reference
Pamuk ON, Ali SM, Hasni S. Development of systemic lupus erythematosus in patients with immune thrombocytopenic purpura: a systematic meta-analysis. Autoimmun Rev. Published online February 11, 2023. doi:10.1016/j.autrev.2023.103297
