ntermountain Central Laboratory, Murray, UT 84157, USA.
Arch Pathol Lab Med. 2010 Nov;134(11):1679-84. doi: 10.5858/2009-0511-OAR1.1.
Complement activation, evidenced by deposition of C4d, is important in the diagnosis of antibody-mediated rejection of cardiac allografts. C4d deposition can be assessed by either immunofluorescence (IF)- or immunoperoxidase (IP)-based methods. The use of methods varies considerably among institutions, but there are few data addressing their diagnostic equivalence.
To compare IF and IP C4d staining on paired endomyocardial biopsy samples from a large number of heart transplant patients.
Retrospectively selected paired frozen and paraffin-embedded samples from the same biopsy were stained for C4d by IF and IP methods. Capillary staining was scored by using a 0, 1+, 2+, 3+ scale.
A total of 296 biopsy pairs from 70 patients were studied. There were two hundred forty-three cases that were scored 0, twenty-four scored 1+, sixteen scored 2+, and thirteen scored 3+ by IF. Two hundred thirty-one cases scored 0, forty scored 1+, ten scored 2+, and fifteen scored 3+ by IP. Complete agreement was seen in 81% of cases. Among discrepant cases, 89% (n = 51) were minor (±1) and 11% (n = 6) were major (±2). Five of the 6 major discrepancy biopsies came from 2 patients, both of whom had concordant (IF and IP) 3+ results on prior biopsies. The weighted κ value for the entire sample set was 0.78 and for the first biopsy only set (to correct for bias introduced by multiple biopsies from the same patient) the weighted κ value was 0.88.
Immunofluorescence and IP C4d staining methods are highly comparable and are both viable options for antibody-mediated rejection surveillance in transplant heart biopsies.
补体激活，表现为 C4d 的沉积，在诊断心脏同种异体移植物的抗体介导排斥反应中很重要。C4d 的沉积可以通过免疫荧光（IF）或免疫过氧化物酶（IP）方法来评估。这些方法在不同的机构中使用差异很大，但关于它们诊断等效性的数据很少。
比较大量心脏移植患者的心脏活检标本中 IF 和 IP 的 C4d 染色。
从同一次活检中选择了 IF 和 IP 方法染色的冷冻和石蜡包埋配对的回顾性样本。使用 0、1+、2+、3+评分系统对毛细血管染色进行评分。
共研究了 70 例患者的 296 对活检。IF 评分 243 例为 0，24 例为 1+，16 例为 2+，13 例为 3+。IP 评分 231 例为 0，40 例为 1+，10 例为 2+，15 例为 3+。81%的病例完全一致。在不一致的病例中，89%（n=51）为轻微差异（±1），11%（n=6）为显著差异（±2）。在 6 个主要差异活检中，有 5 个来自 2 个患者，这两个患者的先前活检均有一致的（IF 和 IP）3+结果。整个样本集的加权κ值为 0.78，仅对首次活检样本集（纠正来自同一患者的多次活检引入的偏差）的加权κ值为 0.88。
免疫荧光和 IP C4d 染色方法高度可比，都是移植心脏活检中抗体介导排斥反应监测的可行选择。
