CD4+ T-lymphocytopenia--a frequent finding in anti-SSA antibody seropositive patients with primary Sjögren's syndrome.

OBJECTIVE: Case reports have described an association between idiopathic CD4+ T-lymphocytopenia (ICL) and non-Hodgkin's malignant lymphoma (NHML), and both entities have an increased prevalence in patients with primary Sjögren's syndrome (SS). We investigated lymphocyte subset counts in patients with primary SS to determine if presence of different autoantibodies is associated with ICL and hence may represent an increased risk for development of NHML.

METHODS: A total of 80 patients with primary SS according to the American-European Consensus Classification Criteria (AECC) and 37 non-AECC sicca patients were studied for presence of different autoantibodies, and lymphocyte subsets were investigated by flow cytometry.

RESULTS: Absolute CD4+ T-lymphocyte counts were significantly lower among anti-SSA antibody seropositive SS patients compared to correlating seronegatives and non-AECC sicca patients (601/microl vs 956/microl and 1087/microl; p < 0.001 and p < 0.001, respectively). ICL was found in 16% of anti-SSA seropositive patients.

CONCLUSION: ICL, a proposed risk factor for development of NHML, occurs frequently and presumably exclusively in patients with primary SS who are anti-SSA antibody seropositive. These findings support that this group comprises patients at risk for development of NHML.