Bilateral inferior petrosal sinus sampling without lateralization is less accurate for the diagnosis of Cushing disease
Shi Chen, Xiaohong Lyu, Weixin Hong, Dingyue Zhang, Yuelun Zhang, Daiyu Yang, Yijing Xu, Zhen Shen, Hui Pan, Huijuan Zhu, Xiaobo Zhang, Lin Lu- Endocrinology, Diabetes and Metabolism
Abstract
Context
During bilateral inferior petrosal sinus sampling (BIPSS), the side-to-side ACTH ratio, referred to as ‘sampling lateralization’, was used to predict pituitary adenoma localization.
Objective
To investigate the potential different diagnostic accuracy of BIPSS for differentiating CD and EAS patients with low-lateralization (IPS:IPS<=1.4) and high-lateralization (IPS:IPS > 1.4).
Design/Setting
Single-center retrospective study (2011-2021).
Patients
220 consecutive CD patients as validation set, and 30 ectopic ACTH secretory syndrome (EAS) patients, with confirmed pathological diagnoses and BIPSS results. 40 CD patients who had digital subtraction angiography (DSA) videos were as discovery set.
Results
In the discovery set, he low-lateralization CD group (n = 11) had a higher median plasma ACTH concentration (62.2, IQR 44.7-181.0 ng/L) than high-lateralization CD group (n = 29) (33.0, IQR 18.5-59.5, P = 0.013). Lower IPS to peripheral ratios were observed in low-lateralization group during BIPSS, both before and after stimulation (P = 0.013 and P = 0.028). The sensitivity of BIPSS before stimulation in differentiating CD from EAS was lower in low-lateralization group than high-lateralization group (54.6% vs. 93.1%, P = 0.003), which was validated in validation set. DSA videos revealed a higher two sides visible vascular area difference of the pituitary in low-lateralization group (median 1.2, IQR 0.5-1.8, *105 Pixel) than another group (0.4, IQR 0.1-0.7, *105 Pixel, P = 0.008). The two sides vascular area ratio was also significantly higher in low-lateralization group (1.55, IQR 1.31-2.20) than high-lateralization group (1.19, IQR 1.07-1.35, P = 0.010).
Conclusion
Our study suggested that the low-lateralization in CD patients may reduce the diagnostic sensitivity of BIPSS, which might be potentially associated with peripituitary vascular anatomy.