1. Presented by Regina Kwon, MD and reviewed by Claire Knezevic, PhD

A middle-aged adult patient presents to an outpatient clinic with a chief complaint of numbness, burning, and tingling in the feet bilaterally that has been worsening over the past few days. The hands are not affected, and the patient also endorses chronic lower back pain. Past medical history is remarkable for meralgia paresthetica. Past surgical history includes several minor outpatient surgical procedures. Social history includes smoking, and daily activities include spending time outdoors and home-maintenance.

A physical exam reveals decreased breath sounds with wheezing and 1+ pitting edema of the ankles. Strength, reflexes, and sensation are within normal limits. Vitals are as follows:

BP: 142/84
HR: 70
RR: 18
T: 36.6 C
BMI: 32.3

You perform an extensive workup, with these results:



What is the best next step?