诊断囊性纤维化 (CF) 并不总是那么简单，特别是当汗液氯化物浓度 (SCC) 处于中等水平并且识别出 <2 个导致 CF 的 CFTR 变异时。指南中提出的生理 CFTR 测定、鼻电位差和肠道电流测量，在所有年龄段都不容易获得也不可行。直肠类器官形态分析（ROMA）先前被证明可以根据明显的表型差异区分患有和不患有CF的受试者的类器官：与非CF类器官相比，CF类器官具有不规则的形状并且缺乏可见的管腔。当前的研究旨在进一步探讨 ROMA 在 CF 诊断不确定时的作用。使用先前建立的 ROMA 协议对类器官形态进行分析。计算了两个指数：用于量化类器官圆度的圆形指数和用于衡量中央腔是否存在的强度比。来自 116 名受试者的直肠类器官与之前研究中的 189 名受试者一起进行了培养和分析。 ROMA几乎完全区分CF和非CF。 ROMA 指数与鳞状细胞癌、胰腺状态和遗传学相关，证明了收敛有效性。对于根据当前指南诊断结果不确定的病例，ROMA 提供了额外的诊断信息，其中 24 例中的 18 例 (75%) 具有诊断性 ROMA 分类。当 SCC 和遗传学不足以进行诊断分类时，ROMA 提供额外的信息来支持 CF 诊断。 ROMA 是标准化的并且可以集中化，允许未来在诊断不明确的情况下作为首选生理检测纳入诊断检查中。© 作者（或其雇主）2024。禁止商业重复使用。请参阅权利和权限。由英国医学杂志出版。

Diagnosing cystic fibrosis (CF) is not always straightforward, in particular when sweat chloride concentration (SCC) is intermediate and <2 CF-causing CFTR variants are identified. The physiological CFTR assays proposed in the guidelines, nasal potential difference and intestinal current measurement, are not readily available nor feasible at all ages. Rectal organoid morphology analysis (ROMA) was previously shown to discriminate between organoids from subjects with and without CF based on a distinct phenotypical difference: compared with non-CF organoids, CF organoids have an irregular shape and lack a visible lumen. The current study serves to further explore the role of ROMA when a CF diagnosis is inconclusive.Organoid morphology was analysed using the previously established ROMA protocol. Two indices were calculated: the circularity index to quantify the roundness of organoids and the intensity ratio as a measure of the presence of a central lumen.Rectal organoids from 116 subjects were cultured and analysed together with the 189 subjects from the previous study. ROMA almost completely discriminated between CF and non-CF. ROMA indices correlated with SCC, pancreatic status and genetics, demonstrating convergent validity. For cases with an inconclusive diagnosis according to current guidelines, ROMA provided additional diagnostic information, with a diagnostic ROMA classification for 18 of 24 (75%).ROMA provides additional information to support a CF diagnosis when SCC and genetics are insufficient for diagnostic classification. ROMA is standardised and can be centralised, allowing future inclusion in the diagnostic work-up as first-choice physiological assay in case of an unclear diagnosis.© Author(s) (or their employer(s)) 2024. No commercial re-use. See rights and permissions. Published by BMJ.