Ćerimagić A, Džananović N
Department of Clinical Immunology, Clinical Centre University of Sarajevo, Bosnia and Herzegovina.
J Transl Autoimmun. 2020 Jan 31;3:100034. doi: 10.1016/j.jtauto.2020.100034. eCollection 2020.
Paraneoplastic cerebellar degeneration (PCD) is a rare disease that is triggered by an abnormal immune response to a malignant tumor by cross-reaction of antibodies. The low prevalence of this condition has not allowed for large-scale randomized controlled trials. Suspecting a paraneoplastic syndrome followed by rapid diagnosis is crucial before the symptoms irreversibely progress. Indirect immunofluorescence (IIF) with HEp-2 cells is currently the most widely used screening technique for the detection of a wide range of nuclear and cytoplasmatic autoantibodies. Here, we present a case of a female Caucasian patient, 61 years of age, who started having sudden symptoms of PCD starting April 2016 that progressed through the course of 10 months before the final diagnosis. Assuming that antinuclear antibodies (ANA) testing could give rise to suspicion of an underlying malignancy but also to an underlying autoimmune etiology of PCD, we followed the ANA patterns of the patient during the course of disease and treatment protocols. A total of four ANA follow ups were done on serum dilution 1:100 and all showed weak positive results on hepatic cells and a mix of similar patterns that, through the course of time, differed slightly on HEp-2 cells. Finding positive antinuclear or anticytoplasmic auto-antibodies might guide toward an extensive and useless search for a systemic autoimmune disease ignoring the possibility of searching for paraneoplastic-specific antibodies. An unspecified mix of patterns should not be ignored and might, through further research, show to be more valuable in the ANA screening than is the case now. Weak positive results should not mislead into thinking that there is no overall effect on health, since quite the opposite was the case here. In our example, neither the tumor response to treatment, neurological presentation nor the immunological treatment had a strong effect on the ANA patterns which remained almost identical throughout the course of disease and treatment. Ultrastructural and molecular events in the pathogenesis of the disease could have caused certain minor changes in the pattern but are not of clinical value at the moment and further research is needed.
副肿瘤性小脑变性（PCD）是一种罕见疾病，由抗体交叉反应对恶性肿瘤产生异常免疫反应引发。这种疾病的低患病率使得无法进行大规模随机对照试验。在症状不可逆转地进展之前，怀疑副肿瘤综合征并进行快速诊断至关重要。目前，使用HEp-2细胞的间接免疫荧光（IIF）是检测多种核和细胞质自身抗体最广泛使用的筛查技术。在此，我们报告一例61岁的白种女性患者，她于2016年4月开始出现PCD的突发症状，在最终诊断前持续了10个月。假设抗核抗体（ANA）检测可能引发对潜在恶性肿瘤的怀疑，但也可能引发对PCD潜在自身免疫病因的怀疑，我们在疾病和治疗过程中跟踪了患者的ANA模式。对血清稀释1:100共进行了四次ANA随访，所有结果在肝细胞上均显示弱阳性，并且有相似模式的混合，随着时间推移，在HEp-2细胞上略有不同。发现抗核或抗细胞质自身抗体阳性可能会导致对全身性自身免疫性疾病进行广泛且无用的检查，而忽略了寻找副肿瘤特异性抗体的可能性。未明确的模式混合不应被忽视，通过进一步研究，可能会发现其在ANA筛查中比目前更有价值。弱阳性结果不应误导人们认为对健康没有总体影响，因为实际情况恰恰相反。在我们的例子中，无论是肿瘤对治疗的反应、神经学表现还是免疫治疗，对ANA模式都没有强烈影响，在疾病和治疗过程中ANA模式几乎保持不变。疾病发病机制中的超微结构和分子事件可能导致模式出现某些微小变化，但目前没有临床价值，需要进一步研究。
