Bacterial DNA linked to short-term Crohn’s disease flare
The presence of bacterial genomic fragments, or bactDNA, in the blood of patients with Crohn’s disease in remission was found to be an independent risk factor for flare in the short term. At 6 months, bactDNA presence also was found to be independently and significantly linked to an increase in hospitalization risk, switch of treatments and steroids startup.
“This effect is independent of established therapy, evidence of mucosal lesion or nucleotide-binding oligomerization domain containing 2 (NOD2) genotype status,” study researchers wrote.
In a prospective, multicenter study, researchers examined time-to-relapse in 288 patients with CD with Crohn’s disease activity index (CDAI) of less than 150. Patients were enrolled from 2012 to 2014, and all patients completed a 6-month follow-up evaluation.
At baseline, the researchers determined bactDNA presence in the patients’ blood (found in 98 patients at baseline) and the NOD2 genotype (found in 114 patients at baseline). Serum cytokine levels also were measured at baseline in all patients. At 6 months, the researchers examined the primary outcome of time-to-relapse as evaluated by CDAI of more than 150.
Fourteen percent (n = 40) of the patients relapsed during the 6-month follow-up. BactDNA was identified as an independent risk factor for relapse using a multivariate survival analysis (HR = 8.75; 95% CI, 4.02-19.06). At 6 months, bactDNA also was associated with hospitalization (P < .001), steroids startup (P < .001) and switch of treatment (P = .002). Also, in the patients with bactDNA or with the variant-NOD2 genotype, serum pro-inflammatory cytokines were significantly increased.
“The present study identifies bactDNA translocation as an independent risk factor of relapse in the short term in CD patients in remission. The presence of this bacterial antigen is also independently associated with a significantly increased risk of other complications such as hospitalization, switch of treatment or the startup of steroids,” the researchers wrote. “The increased inflammatory response to bactDNA translocation, particularly compromised in patients with a variant NOD2 genotype, is likely identifying a subgroup of CD patients susceptible of more aggressive early therapeutic approaches.” – by Suzanne Reist
Disclosure: The researchers report no relevant financial disclosures.