Chlamydia and ocular adnexal lymphomas: An Indian experience

Ocular adnexal lymphomas (OALs) are a heterogeneous group of malignancies, majority being extranodal mucosa-associated lymphoid tissue (MALT) type. Different geographical regions have reported association of Chlamydia with OALs (MALT type). In India, role of Chlamydia in OALs remains unexplored. The aim of this study was to detect Chlamydia and to correlate with clinicopathological features of OALs in India. The clinicopathological features of 41 OAL cases were studied prospectively. Chlamydia DNA was detected by genus specific PCR amplifying major outer membrane protein (MOMP) gene followed by DNA sequencing. Chlamydia immunoexpression was evaluated by immunofluorescence and immunohistochemistry. The results were correlated with clinicopathological features including follow-up and survival. Chlamydia genome was detected in 3/41 (7.3%) OAL cases by PCR. Direct sequencing revealed C. trachomatis in 3 positive cases. Immunofluorescence and immunohistochemistry showed Chlamydia antigen in 5/41 and 1/41 cases respectively. Immunofluorescence demonstrated higher sensitivity than immunohistochemistry. A significant association was observed between Chlamydia positivity and orbital location (P = 0.05). Follow-up revealed relapse in 2 Chlamydia positive cases (P = 0.056). Our results demonstrate for the first time presence of C. trachomatis genome in 7.3% OAL cases in India. As no other reports are documented, more detailed studies from different regions within India are needed to explore status of Chlamydia in OALs.