Institute of Clinical Pathology and Clinic of Rheumatology, University Hospital of Udine, Italy.
Clin Exp Rheumatol. 2014 Jan-Feb;32(1):61-5. Epub 2014 Jan 20.
To assess Chlamydophila psittaci (Cp) subclinical infection in patients with Sjögren's syndrome (SS).
Seventy-four SS patients (55.4 ±13.4 yrs; 94.6% females) were studied. Among them, 18 had salivary gland mucosa-associated lymphoid tissue (MALT) B-cell lymphoma, 20 myoepithelial sialoadenitis (MESA), and 36 no lymphoproliferative disorders (LPD). The presence of Cp DNA was assessed in peripheral blood of all patients by specific PCR protocols. Paired salivary gland samples were also investigated whenever available (34 cases), including lymphomatous and non-lymphomatous samples, as well as major and minor salivary gland tissues. As controls, 225 blood donors were analysed in the peripheral blood.
Overall, Cp DNA was detected in 11/74 (14.9%) SS patients vs. 1/225 (0.4%) controls (p<0.0001). Cp was detected at higher frequency in MALT lymphoma patients (6/18, 33.3%), as compared with MESA (3/20, 15%) or patients without LPD (2/36, 5.6%), (MALT lymphomas vs. others: p=0.02). A similar Cp prevalence was observed in blood vs. salivary gland tissues, however with a higher frequency in the major than in the minor salivary glands (5/18, 27.8%, vs. 1/17, 5.9%, p=0.18). Cp-positive patients were all rheumatoid factor positive (11/11, 100% vs. 40/63, 63.5% Cp-negative; p=0.014), while no difference was noticed for anti-SSA/SSB positivity.
In the light of accepted models of MALT B-cell lymphomagenesis and considering previous data implicating Cp infection in ocular adnexa MALT lymphoma, our results suggest that Cp infection could be involved also in a fraction of patients with SS developing lymphoma. The potential therapeutic implications of these findings appear worthwhile.
评估干燥综合征（SS）患者中鹦鹉热衣原体（Cp）亚临床感染。
研究了 74 例 SS 患者（55.4±13.4 岁；94.6%为女性）。其中，18 例有唾液腺黏膜相关淋巴组织（MALT）B 细胞淋巴瘤，20 例有肌上皮涎腺炎（MESA），36 例无淋巴增殖性疾病（LPD）。通过特异性 PCR 方案评估所有患者外周血中 Cp DNA 的存在。在有条件的情况下，还对配对的唾液腺样本进行了研究（34 例），包括淋巴瘤和非淋巴瘤样本，以及大唾液腺和小唾液腺组织。作为对照，对 225 名献血者进行了外周血分析。
总体而言，Cp DNA 在 74 例 SS 患者中检出 11 例（14.9%），在 225 名对照者中检出 1 例（0.4%）（p<0.0001）。Cp 在 MALT 淋巴瘤患者中的检出率较高（18 例中的 6 例，33.3%），明显高于 MESA（20 例中的 3 例，15%）或无 LPD 的患者（36 例中的 2 例，5.6%）（MALT 淋巴瘤患者与其他患者相比：p=0.02）。Cp 在血液与唾液腺组织中的检出率相似，但大唾液腺中的检出率高于小唾液腺（18 例中的 5 例，27.8%，17 例中的 1 例，5.9%，p=0.18）。Cp 阳性患者均为类风湿因子阳性（11 例中的 11 例，100%，63 例中的 40 例，63.5% Cp 阴性，p=0.014），而抗 SSA/SSB 阳性率无差异。
根据 MALT B 细胞淋巴瘤发生的公认模型，并考虑到先前的研究提示 Cp 感染与眼附属器 MALT 淋巴瘤有关，我们的结果表明 Cp 感染可能也涉及到发生淋巴瘤的一部分 SS 患者。这些发现具有潜在的治疗意义。
