Serum immunoglobulin free light chain levels are higher in girls than boys during eosinophilic oesophagitis.

AIM: Eosinophilic oesophagitis (EO) is an emerging worldwide disease, closely associated with male gender and allergic disorders. This study investigated the distribution of allergy markers in a cohort of children with EO.

METHODS: We analysed allergy markers in 91 children (62 males and 29 females) with EO and a control group of 45 age-matched children who had non-EO gastrointestinal allergic symptoms. The markers analysed were serum cow's milk-specific and hen's egg-specific IgE, thymic stromal lymphopoietin (TSLP), thymus-regulated and activation-regulated chemokine (TARC/CCL17) and immunoglobulin free light chain (Ig-fLC).

RESULTS: In the EO group, cow's milk-specific IgE levels were detectable in 41.9% of males and 62.1% of females and hen's egg-specific levels in 25% of males and 26.9% of females. There was no gender difference in increased TSLP or TARC levels. Kappa Ig-fLC were increased in 5.6% of males and 20.8% of females (p = 0.058) and lambda Ig-fLC in 1.9% of males and 33.3% of females (p = 0.000). No gender differences were found in the control group.

CONCLUSION: Our findings suggest that serum TSLP might be a potential marker of EO and TARC of non-EO gastrointestinal food allergies. In EO, serum Ig-fLC appeared higher in females, adding another gender difference to the biology of EO.