Association of chronic spontaneous urticaria and Chlamydia trachomatis genitourinary infection in men: A case control observational study

Although urticaria has been described as a manifestation of lymphogranuloma venereum caused by L1, L2, L3 serovars of Chlamydia trachomatis and IgG autoantibodies to IgE and IgE receptors have been found, the trigger for autoimmunity is not known.

The present study focussed on the role of C. trachomatis as an aetiology in cases of chronic spontaneous urticaria (CSU).

A case control observational study was conducted over two years in a tertiary care hospital by comparing the presence of C. trachomatis in semen specimens of 30 cases of CSU and equal number of age matched controls by Rapid Antigen Test.

Nine (30%) out of 30 cases of CSU detected C. trachomatis antigen in their semen samples as compared to 2 (6.66%) controls, the difference was found to be statistically significant (X² 5.45 df 1, p 0.0195). Furthermore, average pus cell count in semen specimens of case of CSU was found to be significantly higher in those with C. trachomatis antigen positivity as compared to those who were antigen negative (12.11+/-3.75 and 8.38+/-2.59 respectively p<0.0001).

Since rapid antigen test is a screening test, those testing positive are confirmed as having C. trachomatis infection. Those who test negative can be further tested with nucleic acid amplification test (NAAT) to pick up few more cases.

Chlamydia trachomatis genitourinary infection in males has been found to be a significant cause of chronic spontaneous urticaria in 30% of the cases on Rapid Antigen testing in semen specimens. Further semen was also found to have significantly higher number of pus cells in those who tested positive as compared to those who were negative.