Immunosuppression, the cornerstone of management of inflammatory bowel diseases (IBD) is associated with an increased risk of serious infections that is inadequately predicted by clinical risk factors.
The role of genetics in determining susceptibility to infections is unknown.
From a prospective-consented patient registry, Dr Ashwin Ananthakrishnan and colleagues from Massachussetts, USA identified IBD patients with serious infections requiring hospitalization.
Analysis was performed to identify IBD-related and non-IBD related immune response loci on the Immunochip that were associated with serious infections and a genetic risk score representing the cumulative burden of the identified single nucleotide polymorphisms was calculated.
The team included 1333 IBD patients with median disease duration of 13 years.
A total of 10% of patients had a serious infection requiring hospitalization.
|Each 1 point increase in the infection GRS was associated with a 50% increase in risk of infections|
|Scandanavian Journal of Gastroenterology|
The researchers found that patients with infections were more likely to have Crohn's disease, and had shorter disease duration.
The most common infections were skin and soft-tissue, respiratory and urinary tract infections.
The research team observed that 8 IBD risk loci, and 2 other polymorphisms were significantly associations with serious infections.
Each 1 point increase in the infection GRS was associated with a 50% increase in risk of infections, confirmed on multivariable analysis.
The team noted that genetic risk factors improved performance of a model predicting infections over clinical covariates alone.
Dr Ananthakrishnan's team commented, "Genetic risk factors may predict susceptibility to infections in patients with IBD."