A 27-year-old woman comes to the office due to facial weakness. When the patient woke up this morning, the left side of her face seemed to be "pulling down." She had difficulty eating breakfast, and orange juice leaked out the left side of her mouth. The patient had some minor left ear pain last night that responded to acetaminophen and is fully resolved. She has no chronic medical conditions and takes no other medications. Vital signs are within normal limits. On examination, the external ear, external auditory canal, and tympanic membrane are normal. There is weakness of the entire left side of the face, including the forehead and incomplete eye closure. The pupils are equal and reactive to light. Hearing is intact. Which of the following is the most appropriate next step in diagnosis of this patient?

Question

A 27-year-old woman comes to the office due to facial weakness.  When the patient woke up this morning, the left side of her face seemed to be "pulling down."  She had difficulty eating breakfast, and orange juice leaked out the left side of her mouth.  The patient had some minor left ear pain last night that responded to acetaminophen and is fully resolved.  She has no chronic medical conditions and takes no other medications.  Vital signs are within normal limits.  On examination, the external ear, external auditory canal, and tympanic membrane are normal.  There is weakness of the entire left side of the face, including the forehead and incomplete eye closure.  The pupils are equal and reactive to light.  Hearing is intact.  Which of the following is the most appropriate next step in diagnosis of this patient?

Quizplus · Accepted Answer

11ec25c8_d571_941d_bc81_c78d5d4eb565_MD0003_00 This patient likely has Bell palsy, the most common cause of facial nerve (CN VII) palsy. Bell palsy typically presents with acute-onset (eg, over hours), unilateral, upper and lower facial drooping (peripheral pattern). Other common findings include an inability to raise the eyebrow or close the eye, drooping of the mouth corner (with the mouth drawn to the unaffected side), and disappearance of the nasolabial fold. The development of facial weakness may be preceded by a prodrome of auricular pain or dysacusis (ie, distortion of sound). upper and lower Bell palsy represents >50% of cases of facial nerve palsy, rarely causes multisystemic involvement, and has a very good prognosis (>85% completely recover with high-dose glucocorticoids). Therefore, further diagnostic workup is not cost effective and is not recommended when patients have a classic presentation (eg, acute onset, diffuse, peripheral nerve palsy with no systemic findings suggestive of other conditions). Other causes of facial nerve weakness can often be excluded with a thorough history and physical examination. Patients with Bell palsy typically recover within a few weeks. If facial function has not returned by 4 months, further workup can be considered for secondary causes. (Choice A) Chest x-ray is used to screen for sarcoidosis. Neurosarcoidosis can present with facial nerve palsy; however, the majority of patients already have an established diagnosis of sarcoidosis or have multisystem (eg, cutaneous, ophthalmologic, gastrointestinal) involvement. Therefore, routine chest-x-ray screening is not recommended. (Choice B) Patients with HIV are at risk for sensory peripheral neuropathy. Isolated motor mononeuropathy is an extremely uncommon presentation. Therefore, routine HIV screening is not recommended. (Choice C) Suspected Guillain-Barré syndrome (GBS) should be evaluated with lumbar puncture, which often shows albuminocytologic dissociation. It is extremely unusual not to have limb weakness in GBS. When facial palsy occurs as part of this condition, it is usually bilateral and symmetric. (Choice D) MRI of the head may exclude stroke in patients with facial palsy. However, stroke is unlikely in this patient with no risk factors (eg, advanced age, hypertension) or findings (eg, sparing of upper face, onset over seconds or minutes) suggestive of stroke. Educational objective: Bell palsy, a peripheral neuropathy involving the facial nerve (CN VII), presents with acute, progressive, unilateral facial weakness. In patients with a classic presentation, no further diagnostic workup is needed, and many other causes of facial weakness can be eliminated through a thorough history and physical examination. References: Clinical practice guideline: Bell's palsy. (http://www.ncbi.nlm.nih.gov/pubmed/24189771)

A 27-Year-Old Woman Comes to the Office Due to Facial