Background Vasculitis in primary Sjögren’s syndrome (pSS) may be related to cthe presence of cryoglobulins (cryos) or hypergammaglobulinemia. Cryos reflect a high grade of B-cell lymphoproliferation, possibly leading to malignant lymphoma.
Objectives Patients with pSS with cryos with or without vasculitis, and pSS with hypergammaglobulinemic vasculitis (hypergammaV) were retrospectively compared in a large cohort of consecutive patients.
Methods Clinical, laboratory and histopathologic data in 1170 patients with pSS (1118 females, and 52 males, age at diagnosis 51±14 years) were collected. Univariate analyses were performed.
Results cryos were tested in 850/1170 patients (72.6%), and detected in 59/850 (6.9%). Cryos were significantly associated with male sex (p=0.02), purpura (p<0.0001), renal involvement (p=0.002), haematologic abnormalities (p<0.0001), peripheral neuropathy (p<0.0001), fibromyalgia (p=0.007), lymphoma (p<0.0001), low C3 or C4 complement (p<0.0001 for both), leukopenia (p<0.0001), serum M-component (p<0.0001), hypergammaglobulinemia (p=0.04), anti-SSB (p=0.005), and rheumatoid factor (RF) (p<0.0001). Lip or parotid biopsy was positive in 36/37 pSS patients with cryos who underwent salivary biopsy, and the grade of lymphoid infiltrate in the target tissue correlated with an increased risk of cryos (p<0.0001; OR 2.8, 95%CI 1.8-4.6). Cryoglobulinemic vasculitis (CV) (1), was reported in 3.9% (33/850). CV was significantly associated with renal involvement (p=0.02), with haematologic abnormalities (p<0.0001), peripheral neuropathy (p<0.0001), lymphoma (p=0.001), low C3 or C4 complement (p<0.0001 for both), leukopenia (p<0.0001), serum M-component (p<0.0001), and RF (p<0.0001). Lip or parotid biopsy was positive in all pSS patients with CV who underwent salivary biopsy, i.e. 20/20 and the grade of lymphoid infiltrate correlated with an increased risk of CV (p=0.033; OR 1.67, 95%CI 1.04-2.70). Hypergammaglobulinemia was present in 403/839 (48.0%). HypergammaV without cryos was reported in 48/839 (5.7%). HypergammV was associated with Raynaud’s phenomenon (p=0.005), haematologic abnormalities (p<0.0001), fibromyalgia (p=0.02), but not with other extraglandular involvement. HypergammaV was associated with leukopenia (p=0.001), serum M-component (p=0.02), antinuclear antibodies (p=0.02), anti-SSA (p<0.0001), anti-SSB (p=0.002), RF (p<0.0001). Lip or parotid biopsy was positive in 27/33 pSS patients with hypergammaV, without correlation with the grade of lymphoid infiltrate (p=0.07).
Conclusions pSS with cryos showed both a high grade of activation of peculiar B-cell clones and a high grade of B-cell organization into ectopic salivary MALT. By contrast, hypergammaV was not associated with MALT lymphoid infiltrate. Both cryos alone and CV but not hypergammaV were associated with lymphoma in pSS, indicating that cryos itself represents a red flag for lymphoma in pSS, while hypergammaV did not.
De Vita S, et al. Ann Rheum Dis 2011.
Disclosure of Interest None Declared