Is There an Association between Ocular Adnexal Lymphoma and Chlamydia psittaci Infection? The University of Rochester Experience.

Several subsets of extranodal marginal zone lymphomas of mucosa-associated lymphoid tissues (MALT lymphomas) have been associated with infectious organisms. This finding is of particular significance in the treatment of these conditions because it suggests that eliminating the source of the antigen may result in regression of the malignancy. For example, gastric MALT lymphoma is associated with Helicobacter pylori infection. Antibiotic therapy that eliminates the H. pylori infection frequently causes regression of the lymphoma. Ferreri et al (2004, J Natl Cancer Inst. 96:586) reported the presence of Chlamydia psittaci DNA in 80% of 40 ocular adnexal lymphomas. Consistent with the gastric MALT lymphoma data, a subset of these patients responded well to antibiotic treatment. We used a PCR based assay similar to that of Ferreri et al to analyze a set of ocular adnexal lymphomas and benign (non-neoplastic) lesions for evidence of C. psittaci DNA in patients from New York State. No evidence of C. psittaci DNA was seen in seven MALT-type ocular adnexal lymphomas, four non-MALT B-cell ocular adnexal lymphomas, one Langerhans histiocytosis, and five reactive lymphoproliferations. In addition, we found no evidence for C. psittaci in DNA samples from 21 monoclonal B-cell lymphomas from sites other than the ocular adnexa. We confirmed the negative results using an alternate PCR target in the 23S ribosomal RNA gene. In addition, we used appropriate controls to demonstrate that PCR inhibition and DNA template degradation did not affect our results. We conclude that C. psittaci infection did not play a role in the ocular adnexal lymphoproliferations in our survey. The difference in results with the previous report (Ferreri et al) suggests geographical differences in the incidence of C. psittaci infection, or other unknown disease cofactors.