Background/aims: The analysis of sister chromatid exchanges (SCE), defined as symmetrical exchanges between sister chromatids in peripheral blood lymphocytes, has been used as an indicator of chromosomal instability. The study aimed to find out the frequency of sister chromatid exchanges in patients with Crohn's disease and to find the effect of therapy with anti-tumor necrosis factor (infliximab) on this frequency.
Methodology: A cytogenetic study was performed using peripheral lymphocytes of Crohn's disease patients. SCE frequencies were measured in peripheral blood lymphocyte cultures obtained from demographically similar groups of 21 patients with Crohn's disease and an equal number of healthy controls. Thirteen of the patients were female and mean age was 32.71+/-8.2. For each subject, 50 metaphases were scored to determine the mean SCE frequency.
Results: Mean SCE frequency in Crohn's disease patients was 6.1 (1.7-11.2) per cell, which was significantly higher than the value of 4.8 (3.9-6.8) per cell in the matched controls (p=0.017). Crohn's disease activity index and SCE frequency were significantly lower in patients treated with infliximab (p=0.036 and p=0.033 respectively).
Conclusions: In patients with Crohn's disease, SCE frequency is higher than in healthy people. Infliximab therapy lowers Crohn's disease activity index and SCE frequency.