Nodular regenerative hyperplasia (NRH) can manifest as alternating parenchymal compression/expansion on hematoxylin and eosin (H&E) staining and as reticulin collapse/nodularity on reticulin staining. Histologic diagnosis can be challenging, especially when there is mild disease and on limited biopsy samples. We reviewed clinical and histologic parameters in a large series of NRH. We identified 60 liver specimens convincingly showing changes of NRH and reviewed them for clinical (age, sex, symptoms, lab values, portal hypertension [PHTN], NRH etiology) and histologic (inflammation, sinusoidal dilation, cholestasis, architectural change, portal vascular abnormalities, degree of changes on reticulin) parameters. The cases came from 28 women and 32 men (median age: 54 years). Most (55, 92%) were biopsies. Thirty patients were symptomatic. Forty-five cases showed mild NRH changes on reticulin; 24 of these (53%) showed them on H&E as well. Fifteen demonstrated well-developed changes on reticulin, which were always seen on H&E as well. Sinusoidal dilation was commonly observed in both of these subgroups (88% overall). Portal vascular abnormalities were seen in 33%. Well-developed NRH was diffuse more often than mild NRH (53% vs. 4%, P < 0.0001). Twenty-nine patients had clinically confirmed or likely PHTN. Of these, 21 showed mild and 8 showed well-developed NRH changes; only 3 had concomitant advanced fibrosis. Chemotherapy was the most frequent known cause of NRH; 30 patients lacked any definite etiology. NRH can be difficult to diagnose on biopsy, particularly since mild changes may be visible on reticulin but not H&E; even these patients can have PHTN. Additionally, NRH is often idiopathic, potentially lowering clinical and pathologic suspicion. Pathologists should have a low threshold for ordering reticulin stains, especially when a patient is known to have PHTN. Sinusoidal dilation, while nonspecific, commonly accompanies NRH.

结节性再生性增生 (NRH) 在苏木精和伊红 (H&E) 染色上表现为交替的实质压缩/扩张，在网状蛋白染色上表现为网状蛋白塌陷/结节。组织学诊断可能具有挑战性，尤其是在疾病轻微且活检样本有限的情况下。我们回顾了一系列 NRH 的临床和组织学参数。我们确定了 60 份令人信服地显示 NRH 变化的肝脏标本，并对它们的临床（年龄、性别、症状、实验室值、门静脉高压 [PHTN]、NRH 病因）和组织学（炎症、肝窦扩张、胆汁淤积、结构改变、门静脉异常，网状蛋白的变化程度）参数。这些病例来自 28 名女性和 32 名男性（中位年龄：54 岁）。大多数 (55, 92%) 是活检。30 名患者出现症状。45 例在网状蛋白上显示出轻微的 NRH 变化；其中 24 个 (53%) 也在 H&E 上展示了它们。15 个在网状蛋白上表现出良好的变化，这在 H&E 上也经常看到。在这两个亚组中通常观察到正弦扩张（总体为 88%）。门脉血管异常见于 33%。发育良好的 NRH 比轻度 NRH 更容易扩散（53% 对 4%，P  < 0.0001)。29 名患者有临床证实或可能的 PHTN。其中，21 人表现出轻微的 NRH 变化，8 人表现出良好的 NRH 变化；只有 3 人伴有晚期纤维化。化疗是已知最常见的 NRH 原因。30 名患者缺乏任何明确的病因。NRH 在活检时可能难以诊断，特别是因为在网状蛋白上可能会看到轻微的变化，但在 H&E 上看不到；甚至这些患者也可能患有 PHTN。此外，NRH 通常是特发性的，可能会降低临床和病理学怀疑。病理学家对网状蛋白染色的要求应该较低，尤其是当患者已知患有 PHTN 时。正弦扩张虽然非特异性，但通常伴随 NRH。