Hui Yiang, Chen Sonja, Lombardo Kara A, Resnick Murray B, Mangray Shamlal, Matoso Andres
1 Department of Pathology and Laboratory Medicine, Rhode Island Hospital and Alpert Medical School of Brown University, Providence, Rhode Island, USA.
Pediatr Dev Pathol. 2017 Sep-Oct;20(5):375-380. doi: 10.1177/1093526617693106. Epub 2017 Feb 9.
Histologically, esophageal biopsies should have ≥15 intraepithelial eosinophils (IEEs) per high power field (HPF) to support a clinicopathologic diagnosis of eosinophilic esophagitis (EoE). Children with clinically apparent EoE may show pauci-eosinophilic biopsies due to patchy involvement. Immunostaining (Immunohistochemistry) for arachidonate-15 lipooxygenase (ALOX15) has been demonstrated to be a sensitive marker for EoE. We retrospectively assessed the expression of ALOX15 in 48 biopsies from 21 patients with established diagnosis of EoE and with tissue fragments below the threshold of 15 IEEs/HPF. Fragments were classified into pauci-eosinophilic and non-pauci-eosinophilic groups using cutoffs of 10 and 15 IEEs/HPF. Controls included patients with reflux and normal biopsies. Sixty-five (43.9%) fragments showed <10 IEEs/HPF and 83 (56.1%) showed ≥10 IEEs/HPF. Using a cutoff of 15 IEEs/HPF, 87 (58.7%) fragments showed <15 IEEs/HPF while 61 fragments (41.2%) had ≥15 IEEs/HPF. ALOX15 was positive in 53/65 (81.5%) of fragments with <10 IEEs/HPF versus 82/83 (98.8%) of fragments with ≥10 IEEs/HPF ( P < .001). For a cutoff of 15 IEEs/HPF, 75/87 (86.2%) of pauci-eosinophilic fragments were ALOX15-positive, while 60/61(98.4%) of biopsies meeting the threshold were positive ( P < .001). In 3/21 (14.3%) patients with EoE, all of the fragments (n = 7) were pauci-eosinophilic and all of them were positive for ALOX15. Two of 24 patients with reflux (one with 9 and one with 14 IEEs/HPF) were also positive. Fragments from normal controls (0 IEEs/HPF) were negative. Our results support the utility of ALOX15 immunohistochemistry in supporting the diagnosis of EoE in rare situations with strong clinical suspicion where no fragments reach 15 IEEs/HPF.
在组织学上，食管活检每高倍视野（HPF）应具有≥15个上皮内嗜酸性粒细胞（IEEs），以支持嗜酸性粒细胞性食管炎（EoE）的临床病理诊断。具有明显临床症状的EoE患儿可能因病变呈斑片状而表现为嗜酸性粒细胞较少的活检结果。花生四烯酸-15脂氧合酶（ALOX15）免疫染色（免疫组织化学）已被证明是EoE的敏感标志物。我们回顾性评估了21例确诊为EoE且组织碎片中IEEs/HPF低于15个阈值的患者的48份活检标本中ALOX15的表达情况。使用10和15个IEEs/HPF的临界值将碎片分为嗜酸性粒细胞较少组和非嗜酸性粒细胞较少组。对照组包括反流患者和活检正常的患者。65份（43.9%）碎片显示IEEs/HPF＜10个，83份（56.1%）显示≥10个IEEs/HPF。使用15个IEEs/HPF的临界值时，87份（58.7%）碎片显示IEEs/HPF＜15个，而61份（41.2%）碎片≥15个IEEs/HPF。IEEs/HPF＜10个的碎片中有53/65（81.5%）份ALOX15呈阳性，而IEEs/HPF≥10个的碎片中有82/83（98.8%）份呈阳性（P＜0.001）。对于15个IEEs/HPF的临界值，嗜酸性粒细胞较少的碎片中有75/87（86.2%）份ALOX15呈阳性，而达到阈值的活检标本中有60/61（98.4%）份呈阳性（P＜0.001）。在3/21（14.3%）例EoE患者中，所有碎片（n = 7）均为嗜酸性粒细胞较少，且所有碎片ALOX15均呈阳性。24例反流患者中有2例（1例IEEs/HPF为9个，1例为14个）也呈阳性。正常对照组的碎片（IEEs/HPF为0个）为阴性。我们的结果支持在临床高度怀疑但无碎片达到15个IEEs/HPF的罕见情况下，ALOX15免疫组织化学对EoE诊断的辅助作用。
