A 70-year-old Caucasian male presents to clinic complaining of "some very disturbing whirling attacks." He says that on three occasions in this past week, he suddenly began to feel dizzy, nauseated, and found himself unable to walk or speak properly. During these episodes he also noticed a tingling sensation in his lips and that he had double vision. The symptoms resolved gradually after lasting approximately eight to ten minutes. The episodes happened at different times of day, both while at rest and during activity. His medical history is significant for diabetes mellitus, chronic obstructive pulmonary disease, hypertension, hypercholesterolemia, and a remote myocardial infarction. His current medications include metformin, enalapril, hydrochlorothiazide, simvastatin, albuterol, and aspirin. He has a fifty-pack-year smoking history and drinks 1-2 beers per night. He denies having ever used recreational drugs. His temperature is 36.7C (98F), blood pressure is 142/88 mm Hg, pulse is 82/min, and respirations are 14/min. Funduscopic examination shows some neovascularization of the retinal surfaces. Tympanic membranes are translucent and the light reflex is present. Heart sounds are normal. Auscultation of the chest reveals wheezing and diffusely decreased breath sounds. He is barrel-chested. Abdomen is nontender and bowel sounds are present. Mild peripheral edema is evident. There is a loss of vibratory sensation and altered proprioception and impairment of pain, light touch, and temperature in a bilateral stocking-glove distribution. Ankle reflexes are decreased. His most recent laboratory evaluation included the following: What is the most likely diagnosis?

Question

A 70-year-old Caucasian male presents to clinic complaining of "some very disturbing whirling attacks."  He says that on three occasions in this past week, he suddenly began to feel dizzy, nauseated, and found himself unable to walk or speak properly.  During these episodes he also noticed a tingling sensation in his lips and that he had double vision.  The symptoms resolved gradually after lasting approximately eight to ten minutes.  The episodes happened at different times of day, both while at rest and during activity.  His medical history is significant for diabetes mellitus, chronic obstructive pulmonary disease, hypertension, hypercholesterolemia, and a remote myocardial infarction.  His current medications include metformin, enalapril, hydrochlorothiazide, simvastatin, albuterol, and aspirin.  He has a fifty-pack-year smoking history and drinks 1-2 beers per night.  He denies having ever used recreational drugs.  His temperature is 36.7C (98F), blood pressure is 142/88 mm Hg, pulse is 82/min, and respirations are 14/min.  Funduscopic examination shows some neovascularization of the retinal surfaces.  Tympanic membranes are translucent and the light reflex is present.  Heart sounds are normal.  Auscultation of the chest reveals wheezing and diffusely decreased breath sounds.  He is barrel-chested.  Abdomen is nontender and bowel sounds are present.  Mild peripheral edema is evident.  There is a loss of vibratory sensation and altered proprioception and impairment of pain, light touch, and temperature in a bilateral stocking-glove distribution.  Ankle reflexes are decreased.  His most recent laboratory evaluation included the following:  What is the most likely diagnosis?

Quizplus · Accepted Answer

Explanation: Vertebrobasilar insufficiency (Choice C) is a term for reduced blood flow in the base of the brain, typically secondary to emboli, thrombi, or arterial dissection. The labyrinth and brainstem are commonly affected, and symptoms may include vertigo, dizziness, dysarthria, diplopia, and numbness. The vertigo often resolves on its own, but the condition should not be taken lightly. Risk factors for vertebrobasilar insufficiency include diabetes mellitus, hypertension, hypercholesterolemia, arrhythmia, coronary artery disease, circulatory problems, and a history of smoking cigarettes. Labyrinthitis (Choice A) is a mild, often self-limited condition characterized by vertigo, tinnitus, nausea, and a loss of balance. The disorder often follows a viral illness (eg, influenza). Labyrinthitis may also be caused by trauma, bacterial infection, allergies, benign tumors, and certain medications. Benign paroxysmal positional vertigo (Choice B) is an abnormal feeling of motion triggered by certain provocative positions. The condition is most often attributed to the presence of calcium debris within the posterior semicircular canal. Nystagmus is commonly seen. Panic attacks (Choice D) are discrete periods of intense fear or discomfort. Symptoms may include palpitations, sweating, trembling, shortness of breath, a choking sensation, chest pain, nausea, dizziness, paresthesias, and a fear of dying or losing control. Cataplexy (Choice E) is a sudden, temporary loss of muscle tone that can result in collapse. It is often caused by intense emotions, including laughter. Educational Objective: Vertebrobasilar insufficiency is typically secondary to emboli, thrombi, or arterial dissection. The labyrinth and brainstem are commonly affected, and symptoms may include vertigo, dizziness, dysarthria, diplopia, and numbness.

A 70-Year-Old Caucasian Male Presents to Clinic Complaining of "Some