Related Experiment Video
Updated: Jan 22, 2026

An Orthotopic Sciatic Nerve Xenograft for Neurofibromatosis Type 1 Neurofibromas
Published on: October 10, 2025
Clonidine suppression testing for pheochromocytoma in neurofibromatosis type 1
WingYee Wan1, Bichle Nguyen1, Sky Graybill2
1Internal Medicine, Brooke Army Medical Center, Fort Sam Houston, Texas, USA.
Abstract:
Compared with the general population, rates of pheochromocytoma are higher in neurofibromatosis type 1 (NF1) patients. However, pheochromocytoma testing is often plagued by false positive results. Here we present a patient with NF1, elevated urinary metanephrine levels, and an indeterminate adrenal nodule. Clonidine suppression testing aided diagnosis and led to definitive surgical treatment that confirmed a pheochromocytoma. Pheochromocytoma screening and clonidine suppression testing can both aid in the evaluation for catecholamine-secreting tumours.
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