Lab Studies:
Complete Blood Count with differential was within normal limits, without leukocytosis or eosinophilia. C-Reactive Protein was within normal limits.

Other Studies:
Electromyography (EMG) and nerve conduction studies (NCS) showed no neurogenic disease. <br>X-ray of shoulder showed no osseous abnormality. <br>MRI of the brachial plexus with TOS protocol showed normal signaling of the brachial plexus in all positions. <br>Magnetic Resonance Angiography (MRA) of the chest with and without contrast showed no obvious structural compression of the subclavian artery or brachial plexus. <a href="CaseStudyImages/CS1DupilumabanditsGr-1197.jpg" title="Case Photo #1" data-lity><b>Case Photo #1</b></a> <br>Venous duplex was normal. <br>However, arterial duplex demonstrated &gt; 50% stenosis (with a 3:1 ratio in flow velocity) in the left subclavian artery provoked at 180 degrees of abduction, consistent with arterial Thoracic Outlet Syndrome. <br>After further review with our radiologist, the left subclavian appears slightly more narrowed (red bracket) compared to the right subclavian in the MRA images obtained with elevation of the arms. <a href="CaseStudyImages/CS2DupilumabanditsGr-1197.jpg" title="Case Photo #2" data-lity><b>Case Photo #2</b></a>

Consultations:
The patient was referred to a sports medicine specialist, who ordered an X-Ray, MRI, MRA, and venous/arterial duplex, while making referrals for the patient to see a neurologist and a vascular surgeon. <br>A neurologist ordered and reviewed the EMG and NCS and concluded there were no signs of neurogenic TOS. <br>A vascular surgeon reviewed the MRA, venous duplex, and arterial duplex. <br>The patient also followed with his dermatologist, who recommended that the patient stop dupilumab while making a referral for the patient to see a rheumatologist. <br>A dermato-rheumatologist (dual-certified) concluded that the patient&#039;s symptoms were inconsistent with the classic presentation of dupilumab-associated joint pain. <br>The patient established care with a chronic pain specialist.

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