Neuro Tutoring Practice Questions
A 33-year-old woman with no significant medical history presents to the primary care clinic for jaw weakness while chewing. She states that, for the past 6 months, she has noticed her jaw muscles feel weak after prolonged chewing. Recently, she has also noticed occasional drooping of her eyelids that varies throughout the day and can affect both eyes. The patient does not take any medications on a regular basis. Her heart rate is 82 beats/minute, blood pressure is 124/76 mm Hg, respiratory rate is 14 breaths/minute, oxygen saturation is 100%, and temperature is 97.1°F. Her physical exam reveals pupils that are equal, round, and reactive to light. You note mild ptosis of her left eyelid, and she notes subjective weakness of her jaw with repeated chewing on exam. You perform an ice pack test of her left eye, which is positive. Findings on the rest of her neurologic exam are normal. You obtain serologic testing for acetylcholine receptor antibodies and muscle-specific tyrosine kinase antibodies, which are positive. This confirms your suspected diagnosis. Which of the following is the best next step in management based on this information? Ciprofloxacin 500 mg PO BID for 7 days Intravenous immune globulin Plasmapheresis Prednisone 60 mg PO daily for 14 days Pyridostigmine 180 mg PO BID
E- Pyridostigmine 180 mg PO BID This patient is presenting with transient, progressive muscle weakness of the ocular and bulbar muscles, which is consistent with myasthenia gravis, so pyridostigmine daily would be the most appropriate first-line therapy. She describes muscle fatigability, or muscle weakness, that worsens with prolonged muscle use. Fluctuating muscle weakness and fatigability are characteristic of myasthenia gravis, which is an autoimmune neuromuscular disorder that affects the postsynaptic neuromuscular junction. Myasthenia gravis can be limited to the ocular muscle group or can be generalized if there is involvement of the limbs, bulbar, or respiratory muscles. Myasthenia gravis presents in a bimodal distribution between the ages of 10 and 30 more commonly in the female population and between the ages of 50 and 70 more commonly in the male population. Patients often report fluctuating muscle weakness and fatigability that is worsened later in the day. The fluctuating nature of muscle weakness in myasthenia gravis helps to differentiate it from other neuromuscular conditions, such as amyotrophic lateral sclerosis or Lambert-Eaton syndrome. The most common initial presentation is ocular muscle weakness with diplopia, ptosis, or both. Bulbar muscle weakness can present as jaw fatigability, dysphagia, or voice changes. Myasthenia gravis can also affect the respiratory muscles, which can cause a severe, life-threatening respiratory insufficiency known as myasthenic crisis. The diagnosis of myasthenia gravis can be made clinically based on the patient's history and physical exam. One test that can support the diagnosis is the ice pack test. In this test, an ice pack is placed over the affected extraocular muscles. Neuromuscular transmission increases at colder temperatures, so improvement of ptosis after ice application supports the diagnosis of myasthenia gravis. Serologic testing for antibodies to the acetylcholine receptor and muscle-specific tyrosine kinase, in addition to other autoantibodies, can be used to confirm a diagnosis of myasthenia gravis. Electromyography can also be used for diagnostic confirmation. Acetylcholinesterase inhibitors such as pyridostigmine are the best initial treatment for myasthenia gravis. This class of medications delays the breakdown of acetylcholine, thereby increasing the amount of acetylcholine at the neuromuscular junction. The onset of action of pyridostigmine is within 15 minutes, and the time to maximal benefit is 2 hours after administration. Dosing is variable and must be tailored to each individual patient's needs. Pyridostigmine can cause cholinergic side effects, including abdominal pain, diarrhea, increased salivation, and diaphoresis. Plasma exchange and Intravenous immune globulin (IVIG) can be given for patients with acute exacerbations and myasthenic crises.
A 32-year-old man who works as a carpenter presents with leg numbness. On physical exam, he has decreased light touch and pinprick sensation only in an area around his front pants pocket. Distal leg sensation, strength, and reflexes are intact. Which of the following nerves is most likely involved? Lateral femoral cutaneous Pudendal Saphenous Sural
A- Lateral femoral cutaneous The lateral femoral cutaneous nerve is a direct branch of the lumbosacral plexus, whose main contribution is from the L2 and L3 roots. It travels inferiorly, running lateral to the femoral nerve and underneath the inguinal ligament, ultimately sending cutaneous branches to the proximal, mainly lateral, thigh. This is a common entrapment site for the lateral femoral cutaneous nerve, especially in patients with large abdomens, as in pregnancy or obesity. It also can be irritated by repetitive trunk flexion in a patient who wears large belts, as in a carpenter whose tool belt compresses the inguinal region during repetitive forward bending.
A 24-year-old woman presents to Urgent Care after tripping over her backpack and hitting her head at home. A friend noted brief period of unconsciousness lasting less than 3 seconds. Prior to arrival to urgent care, she vomits once. On your physical exam, she is noted to have a normal physical exam with normal vital signs. According to the Canadian CT Head Rule, which of the following is the most appropriate next step in management? Observation Transfer to emergency department for a CT scan of the head with contrast Transfer to emergency department for a CT scan of the head without contrast Transfer to emergency department for an MRI scan of the head
A- Observation Head injuries can be life threatening therefore it is critical to identify those patients at risk for significant pathology. Serious head trauma can result in an epidural hematoma, subdural hematoma, subarachnoid hemorrhage, intracerebral hemorrhage, and skull fracture. For minor head trauma, guidelines help clinicians decide on whether a head CT scan is needed to diagnose or rule out an intracranial injury. One set of rules called the Canadian CT Head Rule devised a set of criteria seen below on which patients with minor head trauma require a head CT scan. The patient in the clinical scenario does not meet any of these criteria and therefore can undergo a period of observation. The patient should be watched closely for signs of increased intracranial pressure (due to expanding hematoma) such as vomiting, confusion, motor or sensory deficits, visual changes, altered consciousness. It should be noted that the Canadian CT Head Rule is a guideline and any time a clinician feels a patient may have an intracranial injury despite not meeting the Canadian CT Head Rule, the clinician should go ahead and get the head CT scan.
Which of the following is correct regarding multiple sclerosis? Becomes more prevalent the farther you live from the equator More common in men Retinal tear is a common presenting symptom Worsens during the course of pregnancy
A-Becomes more prevalent the farther you live from the equator Multiple sclerosis (MS) is most common in people of Northern European descent. Those of Caucasian descent develop MS at nearly twice the rate of those of African descent in the United States. In many areas of the world, MS is more prevalent in temperate latitudes (approaching 1 in 500 in some locations) and becomes less prevalent toward the equator (1 in 20,000 or rare case reports only in some locations). Multiple sclerosis is a disease characterized by multifocal areas of demyelination in the brain and spinal cord, with associated inflammatory cell infiltrates, reactive gliosis, and axonal degeneration. It typically presents in young adults with episodic neurologic dysfunction. Pathologically, most cases are characterized by multifocal areas of demyelination and gross gliotic scarring in the brain and spinal cord. Classic locations of these lesions, called plaques, are the optic nerves, periventricular white matter, deep white matter, juxtacortical white matter, corpus callosum, cerebellar peduncles, and dorsolateral spinal cord. The presentation of MS is quite variable. The classic presentation involves acute to subacute onset of impaired vision or sensation. Patients may often describe fatigue, depression, bladder urgency, weakness, impaired balance, and impaired coordination.
An 18-year-old man presents with a decreased mental status. Which of the following could be empirically given? Activated charcoal Dextrose and thiamine Flumazenil Syrup of ipecac
B- Dextrose and thiamine In the undifferentiated patient with depressed mental status, empiric delivery of dextrose and thiamine should be considered. Hypoglycemia can manifest with varied presentations. Patients may exhibit lethargy, somnolence, agitation, confusion, altered mental status, seizures, focal neurologic deficits or coma. In all patients with neurologic changes, a rapid finger stick should be obtained. However, in the absence of a finger stick, it is reasonable to empirically treat with dextrose as hypoglycemia is life threatening. 1-2 grams of dextrose/kg should be given intravenously. In patients in whom intravenous access cannot be established, glucagon can be given intramuscularly. This will increase circulating glucose levels by mobilizing glycogen stores. However, it will not work in those patients with limited glycogen stores (chronically ill, malnourished etc.). Thiamine should be given with dextrose to prevent the development of Wernicke encephalopathy although the traditional "thiamine before dextrose" has little basis in the literature.
A 34-year-old man presents to the psychiatric clinic because his wife thinks he has become more irritable, reckless, and paranoid over the past year. During the patient interview, he appears unable to prevent occasional, jerking movements of his arms and torso. He says his father developed the same problem in his 40's and died alone in a psychiatric hospital about 15 years later. Which of the following tests will most definitively diagnose this patient's likely condition? Brain MRI Genetic testing Lumbar puncture Positive emission tomography (PET) scan
B- Genetic testing Genetic testing is the most definitive method of diagnosing Huntington disease, the most likely disease in this patient. Huntington disease is a genetically-passed neurologic disorder with an autosomal dominant inheritance pattern. Patients usually present with symptoms between 30 and 50 years of age and typically first notice mild abnormal movements or intellectual changes. Irritability, personality changes, and antisocial behaviors are common. In the initial stages, the abnormal movements may merely be slight fidgeting or restlessness. However, over the next 15-20 years, the disorder will progress to cause obvious dementia and the stereotypic dystonic posturing and choreiform ("dance-like") movements that are hallmarks of the disease. Huntington disease may be suggested by cerebral atrophy of the caudate nucleus on CT or MRI scanning of the brain. A positive emission tomography (PET) scan might show a reduced striatal metabolic rate. However, genetic testing under the guidance of a licensed genetic counselor is diagnostic. There is no cure for Huntington disease and no treatments exist to slow its progress. Tetrabenazine is usually used to manage the dyskinesia. Phenothiazines or haloperidol may be recommended to provide additional control of movements and to palliate any behavioral disturbances. Clozapine is occasionally needed to manage severe psychiatric effects. All patients with Huntington disease should be given the option to have their offspring referred for genetic counseling to aid in informed reproductive planning.
A 63-year-old man presents to your office accompanied by his wife. She reports a cognitive decline over the last several months. Physical exam shows a shuffling gait and a reduced arm swing. He has no delusions, but is reacting to visual hallucinations. His affect is flat. He has deficits in short-term and long-term memory and confabulates when answering questions. A previous medical provider gave the patient an antipsychotic medication which caused catatonia. Which of the following is the most likely diagnosis? Frontotemporal dementia Lewy body dementia Normal pressure hydrocephalus Parkinson's disease
B- Lewy body dementia Lewy body dementia (LBD) is a dementia similar to Alzheimer's and is characterized by hallucinations, parkinsonian features, and extrapyramidal signs, as well as the cognitive dysfunction common in all dementias. Patients with LBD lose cholinergic neurons which cause the loss in cognitive functioning and a loss in dopaminergic neurons causes the loss in motor control. Lewy bodies occur in the brainstem, midbrain, olfactory bulb, and neocortex. Patients with LBD are very sensitive to neuroleptic and antiemetic medications that affect dopaminergic and cholinergic systems. They respond with catatonia, loss of cognitive function, or develop life-threatening muscle rigidity.
A 67-year-old woman presents with severe unilateral pain in her face. She characterizes the symptoms as lasting only a few seconds and denies any associated nausea, vomiting, dizziness, or blurry vision. Her HEENT exam and neurologic exam are normal. Which of the following statements is correct regarding this patient's condition? Facial droop is associated with this condition Pain is most commonly located in the V2 and V3 cranial nerve distribution Pain is usually bilateral in the elderly population Poor dentition is associated with this condition The typical pain attack lasts 30-60 minutes then resolves spontaneously
B- Pain is most commonly located in the V2 and V3 cranial nerve distribution Trigeminal neuralgia manifests with unilateral facial pain characterized as lancinating paroxysms of pain in the lips, teeth, gums, and chin. The pain is often associated with triggers such as chewing, brushing teeth, shaving, washing or touching the affected area of the face, swallowing, or exposure to heat or cold in the affected area. Pain most often occurs in the maxillary (V2) and mandibular (V3) distribution of the trigeminal (V) nerve. The ophthalmic division (V1) is rarely involved.
A 54-year-old woman presents with bilateral lower extremity weakness. She has no achilles or patellar reflexes. Her sensation appears intact. Her strength is 3 out of 5. An MRI of the thoracolumbar spine is normal. Which of the following is the most appropriate next step in making the diagnosis? CT myelogram Edrophonium test Lumbar puncture Pulmonary function tests
C- Lumbar puncture Guillain-Barré syndrome (GBS) is a polyneuropathy characterized by symmetric weakness typically beginning distally and spreading proximally. Sensory abnormalities may also occur although motor weakness predominates. Some patients present days to weeks after an antecedent upper respiratory or gastrointestinal illness. GBS is diagnosed clinically with the assistance of some additional tests including a lumbar puncture. The results of the lumbar puncture demonstrate a markedly elevated protein and mild pleocytosis.
An 18-year-old college student presents from his dormitory to the emergency department with headache, fever, and stiff neck for two days. He thought he had a cold and has been taking acetaminophen without relief of his headache. He has no medical history. His parents did not have him vaccinated because of worries about autism. Vital signs are T 38.8°C, BP 110/50 mm Hg, HR 137 beats/min, and RR 25/min. He is sleepy but arousable. When you flex the patient's head, you note flexion of the patient's lower extremities (hips and knees). Skin exam reveals diffuse petechiae. What is the most likely diagnosis and recommended therapy? Cryptococcus; amphotericin B and flucytosine Herpes simplex virus; acyclovir Neisseria meningitidis; ceftriaxone plus vancomycin Streptococcus pneumoniae; ceftriaxone plus vancomycin West Nile virus; supportive care
C- Neisseria meningitidis; ceftriaxone plus vancomycin Neisseria meningitidis is a common cause of meningitis in crowded living conditions such as college dorms and military barracks. The classic signs of meningitis are fever, headache, neck stiffness, and mental status change. Petechiae and purpura may also be seen with more advanced cases of meningococcemia. N. meningitidis is an encapsulated bacterium that gains entry through the upper airway and spreads hematogenously to the subarachnoid space. Elements of the capsule trigger an inflammatory cascade, causing the brain and meninges to become edematous, leading to decreased cerebrospinal fluid (CSF) drainage. Disruption of the blood-brain barrier also allows entry of protein and water into the brain, resulting in vasogenic edema. The Brudzinski sign is positive if flexion of the neck results in passive flexion of the hips and knees. It is more sensitive than the Kernig sign. Diagnosis of meningitis is made with lumbar puncture (LP). The LP typically reveals an opening pressure > 30 mm H2O, WBC > 1,000/mcL with > 80% polymorphonuclear leukocytes, glucose < 40 mg/dL, protein > 200 mg/dL, and cultures testing positive for gram-negative bacteria. Early treatment of meningitis is essential. Antibiotics should be administered as quickly as possible, even before lumbar puncture. Ceftriaxone and vancomycin are recommended.
A 36-year-old woman presents to the emergency department with progressive lower back pain. She denies history of fever or trauma, but the pain worsened acutely when she bent over to pick up a box earlier today. Which of the following features is most concerning for cauda equina syndrome? Decreased patellar reflex on the right Decreased sensation of the lateral foot Pain radiating down both legs Positive straight leg raise
C- Pain radiating down both legs Cauda equina syndrome is a neurosurgical emergency that results from sudden compression of multiple lumbar and sacral nerve roots. Often the result of massive central disk herniation, it can also be caused by trauma, malignancy, and epidural abscess or hematoma. Patients present with acute onset of lower back pain with pain, weakness, and numbness affecting multiple levels and both legs. Urinary retention is the most consistent examination finding and has a positive predictive value of 99%. Patients may complain of overflow urinary incontinence. Other findings include saddle anesthesia, decreased rectal tone, and fecal incontinence. Emergent neurosurgical consultation is indicated for operative decompression.
A 19-year-old woman at 34 weeks gestation presents with a 1-day history of progressive left-sided facial weakness. She notes a recent history of an upper respiratory infection. On exam, she is unable to raise her left eyebrow, close her left eye, or smile on her left side. She also reports decreased taste sensation. Her neurologic exam is otherwise unremarkable. Which of the following complications is most commonly associated with the patient's diagnosis? Cavernous sinus thrombosis Descending paralysis Hearing loss Keratitis
D- Keratitis The patient has unilateral facial nerve palsy with no other focal neurologic or systemic findings. Although the differential diagnosis for facial nerve paralysis is extensive and includes infectious, traumatic, and neoplastic etiologies, the most common diagnosis is idiopathic Bell palsy. Bell palsy is characterized by the sudden onset of facial nerve paralysis with symptoms usually peaking by 48 hours. Some 60% of patients have a viral prodrome. In making the diagnosis, careful consideration must be given to the motor function of the forehead; sparing of this region would be characteristic of a central, and not peripheral, etiology. Because the orbicularis oculi muscles are involved, this results in incomplete closure of the eyelids on the affected side and leads to corneal exposure keratitis. It is important to prescribe lubricating eye drops, to keep the corneal epithelium from breaking down, and to patch the affected eye at nighttime.
A 68-year-old man presents to the ED after a fall down twelve stairs. On physical exam, you note a large parietal scalp hematoma. His non-contrast computed tomography scan of the head is shown above. Which of the following is the most likely diagnosis? Basilar skull fracture Epidural hematoma Subarachnoid hemorrhage Subdural hematoma
D- Subdural hematoma This patients imaging and physical examination are consistent with a traumatic acute subdural hematoma. A subdural hematoma is a collection of blood between the dura and the arachnoid mater. Subdural hematomas occur most commonly in individuals with brain atrophy, such as those with alcohol use disorder and elderly patients. Subdural hematomas are significantly more common than epidural hematomas. Subdural hematomas occur when there is rupture of the bridging veins from movement of the brain relative to the skull, such as that seen with acceleration-deceleration injuries. This results in blood filling the potential space between the dura and arachnoid. Subdural hematomas may be acute, subacute, or chronic. Acute subdural hematomas are characteristically seen after a traumatic head injury. Patients typically present with a headache, mental status changes, seizures, or focal deficits. Subacute or chronic subdural hematomas may occur without reported history of trauma in up to 50% of patients. These patients may present with symptoms similar to those seen in acute subdural hematomas; however, they may also present with more indolent symptoms such as personality changes, depression, or memory deficits. Subdural hematoma is diagnosed on non-contrast CT of the head and appears as a crescent-shaped hematoma that may cross suture lines. Management of subdural hematomas includes neurosurgical consultation for possible surgical evacuation; however, small subdural hematomas may be closely observed with serial non-contrast CTs of the head. Indications for emergent surgery in a patient with a subdural hematoma include neurologic deterioration or > 5 mm midline shift on CT.
A 55-year-old woman without significant medical history presents with right-sided facial weakness that began acutely 1 hour prior to arrival. She woke up from sleep this morning with a dry right eye and is now unable to move the right side of her mouth. You ask the patient to smile and raise her eyebrows, and you note a right-sided facial droop and no forehead wrinkling on the right side. Her neurological exam and vital signs are otherwise normal. Which of the following is the most appropriate next step in management? Administer a small dose of edrophonium, followed by a full dose, and observe the patient for improvement of her symptoms Administer intravenous prochlorperazine Obtain a blood glucose level, basic laboratory work, and CT scan of the head Obtain a National Institutes of Health Stroke Scale, bring the patient to the CT scanner, and consult a neurologist Provide prescriptions for corticosteroids, antivirals, artificial tears, and an eye patch and have the patient follow up with her physician
E- Provide prescriptions for corticosteroids, antivirals, artificial tears, and an eye patch and have the patient follow up with her physician This patient has Bell palsy, partial or complete paralysis of the facial nerve (cranial nerve VII). Typical symptoms include sudden onset of unilateral facial paralysis, including the forehead, decreased tearing, hyperacusis, and loss of taste sensation on the anterior two-thirds of the tongue that can progress over 1 to 7 days. Many patients describe a viral prodrome. The physical exam is key in the diagnosis to establish the presence of a peripheral rather than a central seventh nerve palsy. Upper and lower facial weakness is present in the peripheral nerve palsy. In central seventh nerve palsy, common in stroke syndromes, only the lower facial weakness is present. The forehead is spared because of bilateral hemispheric innervations to the forehead muscles. Treatment includes corticosteroids, antivirals (for patients with severe to complete paralysis), artificial tears, and eye protection.
Which of the following disease entities can be treated with the Epley maneuver? Benign paroxysmal positional vertigo Meniere disease Vertebrobasilar insufficiency Vestibular neuritis
A - Benign paroxysmal positional vertigo The Epley maneuver may be curative in patients with benign paroxysmal positional vertigo (BPPV). Vertigo is defined as the sensation or illusion of movement, often spinning, when the patient is standing still. There are numerous causes of vertigo. For matters of diagnosis and management, they are often divided into peripheral causes and central causes. Peripheral causes involve pathophysiologic changes outside of the central nervous system and are typically benign (with the exception of acoustic neuroma). Central vertigo, on the other hand, is generally caused by a dangerous etiology affecting the central nervous system (vertebrobasilar insufficiency, cerebellar hemorrhage, and occlusion of the posterior inferior cerebellar artery). BPPV typically involves rapid onset of vertigo with nausea and vomiting that is elicited with moving the head to a certain position and relieved by moving the head away from that position. It is typically caused by the presence of an otolith in one of the semicircular canals in the inner ear. A Dix-Hallpike test can be performed to aid in diagnosis and an Epley maneuver can be used to dislodge the otolith from the semicircular canal leading to a resolution of symptoms.
A 23-year-old man presents to the emergency department via ambulance from the scene of a motor vehicle collision in which he was an unrestrained passenger. The patient was intubated at the scene due to a Glasgow Coma Scale score of 4. On arrival to the emergency department, the patient has an oxygen saturation of 92% intubated, HR of 90 bpm, T of 98°F, and RR of 13/min with the ventilator. The patient is assessed for other injuries via the Acute Trauma Life Support protocol with no acute findings. He is in a cervical collar. Noncontrast head CT is obtained in the emergency department and shows no skull fracture but does show multiple cerebral contusions. After several days in the ICU, the patient is not improving. He remains intubated and unresponsive, except to painful stimuli. What is the suspected diagnosis based on the patient's symptoms? Diffuse axonal injury Epidural hematoma Intraventricular hemorrhage Subarachnoid hemorrhage Subdural hematoma
A- Diffuse axonal injury Traumatic brain injury is defined as an alteration in brain function due to an external force. The force could be from the patient's head being struck by an object, the head striking an object, penetration of the brain, acceleration/deceleration injury, or other forces. Risk factors include having a lower socioeconomic status, alcohol and drug use, and underlying psychiatric or cognitive disorders. Younger age and increased age are also risk factors. A traumatic brain injury can be categorized in many different ways, most commonly by using the Glasgow Coma Scale (GCS). The GCS categorizes injury based on eye opening, motor, and verbal response. A score of 13-15 is mild injury, 9-12 is moderate injury, and 8 or less is severe injury. Diagnosis of a mild traumatic brain injury can be made clinically after a patient has head trauma, and the paitent may have memory impairment, confusion, nausea, and dizziness but no neurological deficits. Imaging is not usually needed. Treatment includes observation and supportive care with close follow-up. Moderate and severe traumatic brain injury are diagnosed from physical exam, GCS score, and findings on imaging with CT head. Treatment includes possible intubation based on chest rise, oxygen saturation, and GCS score. Management of blood pressure and oxygen saturation are important, as well as involvement of the neurosurgical team. Diffuse axonal injury, considered a moderate to severe traumatic brain injury, occurs from shearing forces along white matter tracts causing focal cerebral contusions and hematomas.MRI is the most diagnostic, but CT can also aid in the diagnosis. As noted above, multiple cerebral contusions will be present. It can also be characterized by coma without focal lesion with axonal damage present in multiple regions of the brain parenchyma. Treatment is focused on managing vital signs, glucose, and intracranial pressure. The damage to the brain with diffuse axonal injury is often irreparable, and the prognosis is usually poor.
In the initial diagnostic evaluation of a patient with undifferentiated polyneuropathy, which of the following approaches is most appropriate? Electrodiagnostics, then laboratory testing Electrodiagnostics, then nerve biopsy Laboratory testing, then electrodiagnostics Laboratory testing, then nerve biopsy
A- Electrodiagnostics, then laboratory testing In the workup of suspected polyneuropathy, first assess for the possibility of the more common underlying causes, such as diabetes mellitus, alcohol abuse, medication side effects, chronic renal impairment (uremia), and HIV, by taking a complete detailed history. In those patients with common known underlying conditions and mild symptomatology, an extensive initial diagnostic workup may be unnecessary. However, in patients with unknown underlying conditions, or those with moderate, severe, or progressive symptoms, the initial diagnostic workup should begin with electrodiagnostic testing such as electromyography and/or nerve conduction studies. Laboratory studies can be ordered based on electrodiagnostic testing results and history and examination findings.
What is the genetic basis of Huntington disease? Expansion of the cytosine-adenine-guanine trinucleotide repeats in the HTT gene Hemizygous deletion of up to 28 genes on chromosome 7q11.23 Mutations in the fibrillin gene Mutations in the gene encoding phenylalanine hydroxylase
A- Expansion of the cytosine-adenine-guanine trinucleotide repeats in the HTT gene Huntington disease (HD) is an autosomal dominant inherited, neurologic disorder characterized by choreiform movements, dementia and psychiatric disturbances. The pathophysiology of the disease is still not fully understood. Diagnosis is with genetic testing. Asymptomatic patients with a known family history of HD may also request genetic testing prior to the onset of symptoms. Genetic testing in individuals with HD will show expansion of the cytosine-adenine-guanine trinucleotide repeats in the HTT gene. There is no cure and no disease-modifying treatment available at this time. Treatment focuses on supportive care for the patient and family along with management of symptoms. HD is progressive with the end stages of the disease being severe disability and then death.
What level does the spinal cord terminate in adults? L1-L2 L2-L3 L3-L4 L4-L5
A- L1-L2 The level of the spinal cord varies by age as the spine grows. Knowing the level is essential knowledge prior to performing a lumbar puncture. In the fetus, the spinal canal and spinal cord are equal in length. But, growth of the spinal cord does not keep pace with the growth of the spinal canal. In adults and older children the spinal cord (conus medullaris) terminates at the lower level of the L1 spinal nerve or the body of L2. Therefore, the best approach for a lumbar puncture is between the L3-L4, L4-L5 or L5-S1 interspace.
A 38-year-old man presents with the worst headache of his life. A magnetic resonance angiogram is obtained which demonstrates a large unruptured cerebral aneurysm of the posterior communicating artery. Which of the following are you most likely to find on physical examination? Cranial nerve III palsy Cranial nerve V palsy Cranial nerve VI palsy Cranial nerve VII palsy
A-Cranial nerve III palsy Cranial nerve III palsy is a likely physical examination finding in a patient presenting with a subarachnoid hemorrhage due to a cerebral aneurysm. A subarachnoid hemorrhage is bleeding within the subarachnoid space of the brain and is most commonly caused by a cerebral aneurysm or an arteriovenous malformation. A cerebral aneurysm is a ballooning of the blood vessels of the brain that when under continued pressure can rupture. This is a medical emergency which requires immediate intervention. An unruptured cerebral aneurysm is often incidentally found on brain imaging or when screening for a cerebral aneurysm if a patient has a strong family history. Patients are typically asymptomatic with an unruptured aneurysm but may become symptomatic if increased pressure on the aneurysm continues. Characteristic findings of both unruptured and ruptured cerebral aneurysms include headache, often the worst headache of life, cranial nerve III deficit, and visual loss. Cranial nerve III is the oculomotor nerve which can become compressed when a cerebral aneurysm is present at the junction of the internal carotid artery and posterior communicating artery, causing a unilateral strict downward gaze, ptosis, anisocoria, and blurred vision. When a cerebral aneurysm causes a cranial nerve III deficit with no other neurological symptoms, the aneurysm is likely to be unruptured, but is large enough to compress the nerve.
A 27-year-old man presents to your office with a complaint of numbness and weakness in his feet and fingers that began 24 hours ago. He tells you that two weeks ago he had an upper respiratory infection, but is otherwise healthy. Physical exam 4/5 motor of the lower extremities and absent deep tendon reflexes. Which of the following is the most likely diagnosis? Botulism Guillain-Barré syndrome Lyme disease Multiple sclerosis
B- Guillain-Barré syndrome Guillain-Barré syndrome (GBS) is a post-infection, immune-mediated polyneuropathy. The cardinal feature of GBS is progressive, ascending, symmetric muscle weakness that begins in the lower extremities. Two-thirds of patients with GBS report a viral or bacterial infection prior to the onset of symptoms, most commonly upper respiratory or gastrointestinal. Muscle weakness progresses over hours to days and may eventually affect the muscles of respiration. Diagnosis is initially made based on clinical presentation and may be confirmed with cerebrospinal fluid analysis or neurophysiology studies including nerve conduction studies or needle electromyography. Patients diagnosed with GBS need to be hospitalized for close monitoring until it is determined where the patient is in the course of the disease. Many patients develop respiratory failure and require admission to the intensive care unit. Supportive care is the most important treatment modality for patients with GBS. Patients should receive deep vein thrombosis prophylaxis, bladder and bowel care, physical therapy and emotional support as part of their management plan. Prognosis ranges from full recovery to death, based on severity of symptoms and progression of the disease.
A 49-year-old woman presents with headaches that occur nearly every afternoon since she switched jobs 6 months ago. She describes squeezing pain at her forehead, accompanied by fatigue and poor concentration. Her exam is normal except for posterior neck tenderness, which she attributes to stress at work. Which of the following interventions would be most helpful to this patient? Headache abortive therapy with sumatriptan Headache prevention with amitriptyline Headache prevention with daily verapamil High dose prednisone taper
B- Headache prevention with amitriptyline Amitriptyline would be most helpful for headache prevention in this patient who is describing tension-type headaches. Tension headaches are very common and tend to present as a bilateral headache in a band-like distribution with pain in the frontal and occipital regions. It is the most common type of primary headache. A physical exam may reveal focal areas of tenderness at the posterior neck, where pain and stiffness radiate upward causing pain at the back of the head and a vice-like discomfort around the skull. Neurologic exams should be normal. Tension headaches frequently occur during times of stress, and the clinician should be alert to underlying, untreated depression or anxiety. Tricyclic antidepressants such as amitriptyline have been shown to be effective for depressive symptoms as well as headaches and other chronic pain symptoms. Beyond this, avoidance of triggers, such as stress, poor sleep, loud noises, and light glare, can help. Patients should also be counseled to try daily stretches, biofeedback exercises, hot compresses on the posterior neck, and massage as ways of inducing relaxation of the neck and body in general. If these interventions are not helpful or new symptoms such as nausea and vomiting develop, clinicians should reconsider whether a diagnostic overlap with migraines may be possible as tension headaches and migraine headaches commonly occur together.
A 44-year-old woman presents with a bilateral throbbing headache and nausea that was preceded by vision changes of flashing lights and blind spots. Her past medical history is significant for poorly controlled hypertension. Currently, her blood pressure is 182/100 and neurological examination is normal. CT scanning reveals no intracranial pathology. Which of the following is the most appropriate headache treatment at this time? High flow oxygen Ibuprofen Sumatriptan alone Sumatriptan plus ergotamine
B- Ibuprofen Migraine headaches are characterized by 4-72 hours of unilateral or bilateral head pain which is associated with neurologic, autonomic and psychological symptoms. Three subtypes exist. Migraine with aura only accounts for 20% of migraines. This type of headache is preceded by 30 minutes to 1 hour of prodrome symptoms: weakness, paresthesias and several visual changes including scotoma (blind spots), hemianopia, fortification (zigzag patterns) and scintilla (flashing lights). Migraine without aura is headache without preceding prodrome symptoms. Finally, chronic migraine (or episodic migraine without aura) is a progressive form characterized by increasing symptom frequency and comorbid psychiatric conditions such as depression, anxiety, bipolar disorder, panic disorder and obsessive-compulsive disorder. The pathophysiological basis of migraine is brain "hypersensitivity" caused by trigeminal nerve and upper cervical nerve excitation of perivascular inflammation. Up to 90% of migraine sufferers have a positive family history. The majority of patients are adult females. Associated nonprodromal symptoms include nausea and vomiting, sensitivity to light (photophobia; prefer to be left alone in a dark room), sensitivity to sound (phonophobia), blurred vision and polyuria. Abortive treatment consists of acetaminophen-aspirin-caffeine, NSAIDs (ibuprofen), antiemetics, ergotamine and triptan medications. Preventive treatment of migraine consists of tricyclic antidepressants, beta-blockers, anticonvulsants, ergot-derivatives, tizanidine, occipital nerve blocks, botulinum toxin injection and calcium channel blockers.
A 35-year-old woman with a known history of seizure disorder is actively seizing in the ED. Which of the following is the first-line medication and route to treat her seizure? Intramuscular fosphenytoin Intravenous midazolam Oral lorazepam Rectal diazepam
B- Intravenous midazolam In an actively seizing patient, attention is always directed to the airway first. A patient having a generalized tonic-clonic seizure has a suppressed gag reflex and is prone to aspiration of gastric contents. Therefore, patients should be placed in the left lateral decubitus position. First-line pharmacologic management for an actively seizing patient is a parenteral benzodiazepine. Benzodiazepines directly enhance GABA-mediated neuronal inhibition, affect clinical and electrical manifestations of seizures, and are highly effective at terminating seizure activity. Benzodiazepines have been shown to be more effective than phenytoin at terminating status epilepticus. They are as effective as parenteral phenobarbital, but phenobarbital is associated with a higher risk of hypoventilation and hypotension. The intravenous route is the preferred route to administer an antiepileptic because this has the quickest onset of action. Therefore, intravenous midazolam is the preferred agent from the choices listed above. Midazolam's onset of action is within one minute. In addition to the intravenous preparation, it is available in both intranasal and buccal formulations. It also has the least cardiovascular effects among benzodiazepines.
A 21-year-old man presents to the emergency department with headache, fever, and vomiting. He has been febrile and acting lethargic for the past three days. On exam, a petechial rash is noted on his lower extremities and sacral area. Which of the following signs is most likely to be positive in this patient? Kehr sign Kernig sign Murphy sign Obturator sign
B- Kernig sign The Kernig sign is most likely to be positive in patients with meningitis. Meningitis is an inflammatory disorder of the meninges. Meningitis can be caused by bacteria, viruses, parasites, or drugs. The most common causes of community acquired bacterial meningitis are Streptococcus pneumoniae, Neisseria meningitidis, and Listeria monocytogenes. Healthcare-associated bacterial meningitis is usually occurs after neurosurgery and is usually caused by Staphylococci and gram-negative bacilli. Some of the most common risk factors for meningitis include age extremes (< 5 years or > 60 years), diabetes mellitus, renal insufficiency, immunosuppression, human immunodeficiency virus (HIV) infection, crowded housing (e.g. military recruits, college dorms), intravenous drug use, and alcoholism. Patients with bacterial meningitis typically present with fever, headache, and altered mental status. Nuchal rigidity is present in the majority of patients. Nuchal rigidity can be assessed by actively or passively flexing the neck, or with Brudzinski sign or Kernig sign. A positive Brudzinski sign occurs when the patient flexes his or her hips and knees in response to neck flexion. Kernig sign is positive when the knee cannot be fully extended when the patient is lying supine with the hip flexed. Many patients with meningitis caused by N. meningitidis will have characteristic skin manifestations like petechiae and purpura. Laboratory studies should include complete blood count, blood cultures, and lumbar puncture. A computed tomography (CT) scan may be required prior to lumbar puncture to assess for increased intracranial pressure. The typical cerebrospinal fluid findings, in patients with bacterial meningitis, are increased white blood cell count and decreased glucose. Antibiotics should be initiated as quickly as possible after the lumbar puncture is performed however antibiotics should be initiated empirically if the CT or LP is delayed. Intravenous antibiotics should be directed against the most likely bacteria based on the patient's age, underlying risk factors, and comorbid diseases. Dexamethasone is a common adjunctive therapy used to diminish rates of permanent neurologic sequelae such as hearing loss, intellectual impairment, and focal deficits.
A 40-year-old man with HIV presents with two weeks of progressive headache, malaise, and fever. On examination, he has mild nuchal rigidity, confusion, and a temperature of 38.2°C. Cerebrospinal fluid analysis shows a white blood cell count 360 cells/mL with a mononuclear predominance, glucose 28 mg/dL, and protein 220 mg/dL. What is the treatment of choice? Acyclovir Amphotericin B Ceftriaxone Vancomycin
B-Amphotericin B Cryptococcal meningoencephalitis is an opportunistic infection that occurs primarily in patients with advanced AIDS, although it can be seen in immunocompromised transplant patients as well. The majority of HIV-related cases occur when the CD4 count is < 100 cells/mm3. Patients present with progressive headache, nausea, malaise, and fever over the course of 1 - 2 weeks. Examination findings are typical for meningitis and include altered mental status, photophobia, and fever. Meningismus is less commonly seen. Presentations can be subtle and a high index of suspicion is needed for diagnosis. A CT scan of the brain is indicated if there are signs of increased intracranial pressure or focal neurologic deficits. Lumbar puncture should be performed with careful measurement of the opening pressure. Cerebrospinal fluid will show a mildly elevated white blood cell count with a mononuclear predominance, decreased glucose, and mildly elevated protein. However, in some cases the cerebrospinal fluid will only show minor, if any, abnormalities. Cryptococcal antigen testing of the CSF is nearly 100% sensitive and specific. India ink staining will show budding organisms. Treatment of choice is intravenous amphotericin B in addition to oral flucytosine for 14 days followed by an 8 week course of oral fluconazole.
A 40-year-old man presents to the office with his wife, who states she has noticed some personality changes and aggressive behavior that began a few months ago. He is now having brief, irregular involuntary movement of his arms, is unable to focus, and is having trouble problem-solving. His wife also describes excessive blinking and head thrusts. Which of the following conditions are these findings suspicious for? Alzheimer disease Huntington disease Parkinson disease Wilson disease
B-Huntington disease Huntington disease is a fully penetrant autosomal dominant neurodegenerative disorder caused by an expanded trinucleotide (CAG) repeat in the gene for the protein huntingtin. The prevalence is approximately 10 per 100,000. Symptoms include a combination of a movement disorder, psychiatric disturbances, and cognitive dysfunction. Early on, the movement disorder is predominantly chorea, but parkinsonism and dystonia develop later. Some patients, especially those with juvenile onset, have a more rapidly progressive akinetic-rigid and dystonic form (the Westphal variant). Psychiatric manifestations, which are universal but widely variable, include personality changes, impulsiveness, aggressive behavior, depression, and paranoid psychosis. These psychiatric symptoms may precede the motor manifestations, and psychotropic drug therapy may be incorrectly blamed for the subsequent development of the movement disorder. Cognitive changes result in progressive subcortical dementia with disturbed attention, concentration, judgment, and problem-solving that differs from the typical cortical dementia of Alzheimer disease. Oculomotor dysfunction most often manifests in difficulties with refixating the gaze, and a resulting tendency to use blinks and head thrusts is common. The diagnosis is confirmed by genetic testing.
A 45-year-old woman presents to her primary care provider complaining of pain and paresthesias in the first three digits of her left hand. The symptoms worsen at night. She has a history of hypothyroidism. Which of the following tests is most likely to be positive in this patient? Finkelstein test McMurray test Phalen test Thompson test
C - Phalen Test Phalen's test can be used to evaluate for carpal tunnel syndrome. Carpal tunnel syndrome (CTS) is a collection of signs and symptoms caused by compression of the median nerve within the carpal tunnel. CTS is the most common compressive focal mononeuropathy. Increased intra-carpal canal pressure is a key cause of clinical CTS. Risk factors for the development of CTS include obesity, female sex, pregnancy, diabetes, hypothyroidism, rheumatoid arthritis, aromatase inhibitor use, and occupational factors (e.g. repetitive hand and wrist use, vibrating tool use, sustained wrist or palm pressure). Patients with CTS classically present with pain or paresthesias in the median nerve distribution. Symptoms are often worse at night and provoked by activities that involve flexing and extending the wrist. Patients with severe cases may notice weakness or clumsiness when using the affected hand. The Phalen and Tinel tests are physical exam tests used to aid in the diagnosis. The Phalen test involves flexing the wrist and pressing the posterior aspect of the hands together. The Tinel test is performed by tapping the wrist over the median nerve. The diagnosis of CTS is a clinical diagnosis. Nerve conduction studies and needle electromyography can be used to exclude other conditions and determine the severity of the median nerve injury. Mild to moderate disease is initially managed with nonsurgical approaches such as splinting, oral and injection glucocorticoids, and physical therapy. Surgical decompression is often recommended in patients who present with severe disease. The majority of women who develop CTS during pregnancy will improve after delivery.
A 68-year-old man presents with complaints of a progressive, constant headache for the last three weeks. He was involved in a low speed motor vehicle collision a few days before the headaches began, but did not seek medical attention at the time because of a lack of symptoms immediately following the event. He takes aspirin and lisinopril daily. He denies a prior history of headaches. Noncontrast computed tomography of the head reveals a thin, crescent-shaped collection that is hypodense relative to the adjacent parenchyma. The lesion extends from the right frontal lobe to the ipsilateral falx cerebri, without crossing the midline. Which of the following is the most likely diagnosis? Acute epidural hematoma Acute subdural hematoma Chronic subdural hematoma Subarachnoid hemorrhage
C- Chronic subdural hematoma Chronic subdural hemorrhage occurs because of rupture of the bridging veins between the dural sinuses and the surface of the brain. Subdural hemorrhage is described as chronic if it is at least three weeks old, and often follows so-called 'trivial' head trauma that may not be readily recalled by the patient. Older individuals typically demonstrate cerebral atrophy, which is thought to increase the tension on the bridging veins, and their risk of rupture. Thus, the elderly are more likely than are the young to develop a subdural hemorrhage after a minor head injury. The presentation ranges from asymptomatic to comatose, although the most common symptom is headache. The initial imaging study of choice is a CT scan of the head, which characteristically shows a crescent-shaped collection of fluid that is hypodense relative to the brain or isodense relative to the cerebrospinal fluid. The blood products are not limited by dural attachments, although meningeal folds prevent the hemorrhage from crossing the midline, and blood may extend adjacent to the falx cerebri or tentorium. The management can be conservative or involve surgical drainage, depending on several factors, including the degree of midline shift caused by the hemorrhage, progression of the hematoma, neurologic deficits, and overall health of the patient. Large volume subdural hemorrhages left untreated can produce substantial midline shift, potentially resulting in brain herniation and death.
A 50-year old woman presents to her primary care provider's office with complaints of difficulty walking and balancing. The weakness started in both of her feet, but has now progressed to her knees and hips. She has an unremarkable past medical history except for a recent gastrointestinal infection with Campylobacter jejuni. Which of the following exam findings would this woman most exhibit? Choreiform movements and dyskinesia Diminished or absent deep tendon reflexes Hyperreflexia of the patellar reflex Resting tremor and immobile faces
C- Diminished or absent deep tendon reflexes Patients with Guillain-Barré syndrome would most likely have diminished or absent deep tendon reflexes. Guillain-Barré syndrome (GBS) encompasses a heterogeneous group of acute immune-related polyneuropathies. GBS most commonly presents following a preceding respiratory or gastrointestinal infection, which is thought to trigger an autoimmune response against axons. Campylobacter jejuni is the most commonly recognized precipitant of GBS. The hallmark symptoms of GBS are bilateral, progressive, symmetrical muscle weakness and paralysis, accompanied by diminished to absent deep tendon reflexes. In 90% of cases, the weakness begins in the legs and ascends. Tachycardia, hypotension, and other manifestations of autonomic dysfunction occur in approximately 70% of patients. Sensory involvement is usually less obvious than motor symptoms. The clinical course of GBS typically progresses over a period of two weeks. The cerebrospinal fluid of patients with GBS typically has an elevated protein concentration and a normal white blood cell count. Antibody testing may be of benefit in some GBS variants. All patients with suspected GBS should be admitted due to the risk of respiratory compromise. Intensive care unit admission is warranted for any patients with labile dysautonomia. Plasmapheresis and intravenous immunoglobulin are the main treatment methods. Corticosteroids are not typically indicated. Physical, occupational, and speech therapy should be considered for most patients. Most patients are able to ambulate independently within six months and about half of patients regain full strength within one year.
A 60-year-old man is admitted to the general medicine floor. He presented to the emergency department 1 week ago with bilateral leg weakness that had worsened to include bilateral arm and hand weakness after recovering from a recent gastrointestinal infection. You are performing your daily rounds. The patient reports feeling well this morning. On exam, he has a T of 97°F, RR of 18/min, oxygen saturation of 99% on room air, HR of 85 bpm, and BP of 117/77 mm Hg. The patient has not had trouble breathing independently. Based on the suspected diagnosis, what is the most likely exam finding? Bilateral papilledema Cogwheel rigidity Hyporeflexia Paresthesias Urinary retention
C- Hyporeflexia Guillain-Barré syndrome is an immune-mediated polyneuropathy that is triggered from an event such as recent illness, commonly gastrointestinal illness or influenza. It can also be triggered by vaccinations, although the risk is very low. Gastrointestinal illness is the most common preceding event. It will present with symmetric, ascending, progressive muscle weakness, and up to 90% of patients will have diminished or absent deep tendon reflexes on initial exam and hyporeflexia will be present at the nadir of the disease. Patients may develop complete paralysis. Dysautonomia or autonomic dysfunction can also be a physical exam finding and may present as hypertension, ileus, fever, tachycardia, or urinary retention. Many patients will have to be intubated due to the ascending muscle weakness affecting their respiratory system. Diagnosis is clinical and must include progressive, ascending weakness with hyporeflexia. Diagnosis is confirmed via lumbar puncture which reveals elevated protein but normal white blood cell counts. If diagnosed within 4 weeks of symptom onset, intravenous immune globulin (IVIG) therapy is recommended. Otherwise, care is supportive and focused on rehabilitation. About 80% of patients will recover fully within 1 year.
A 69-year-old man with a history of atrial fibrillation had a syncopal episode while on vacation in India and struck his head on the stairs. He was transported to the local clinic to be evaluated. His wife accompanied him and she informs the provider that her husband is on a "blood thinner" but she is not sure which one. The patient is alert but is not oriented to time or place. You suspect a subdural hematoma but there is no access to a CT scanner at this time. His vital signs are within normal limits. While awaiting transportation to a facility with a CT scan, which of the following labs should be ordered? Alcohol level Basic metabolic profile INR, PT, aPTT, and platelet count Vitamin K level
C- INR, PT, aPTT, and platelet count Elderly patients on anticoagulation therapy are at high risk of subdural hematomas when they fall. In general, elderly patients are at risk of falls because they tend to have balance difficulties and decreased vision in older age. A non-contrast CT of the head is the gold diagnostic standard for diagnosing a subdural hematoma. A subdural hematoma usually appears as a hyper dense, crescent-shape-mass between the skull and the brain. A coagulation panel is necessary in the workup of a suspected subdural hematoma because individuals on anticoagulants or who are alcoholics may have an associated coagulopathy placing them at higher risk for a subdural hematoma. In addition, if INR levels are found to be elevated, reversal agents (e.g. vitamin K and fresh frozen plasma can be administered). Therefore, all patients with a head injury should have at least a basic coagulation panel (INR, PT, aPTT, and platelet count). Fresh frozen plasma or platelets should be given as needed.
A 32-year-old woman complains of a band-like pressure around her forehead that radiates down to the back of her neck. These headaches occur twice a week on average and last for approximately 1 hour in duration. Her neurological exam is within normal limits and she has no other associated symptoms. What is the best initial abortive treatment? Amitriptyline Caffeine Ibuprofen Promethazine
C- Ibuprofen Tension-type headaches cause pain that is mild or moderately intense and is described as tightness, pressure, or a dull ache. The pain is usually experienced as a band extending bilaterally back from the forehead across the sides of the head to the occiput. Patients often report that this tension radiates from the occiput to the posterior neck muscles. In its most extensive form, the pain distribution is "cape like," radiating along the medial and lateral trapezius muscles covering the shoulders. Tension-type headaches can last from 30 minutes to several days and can be continuous in severe cases. In addition to its characteristic distribution and intermittent nature, the history obtained from patients with tension-type headache discloses an absence of signs of any serious underlying condition. Patients with tension-type headache do not typically report any visual disturbance, fever, stiff neck or recent trauma. Treatment goals for patients with tension-type headache should include recommending effective over the counter analgesic agents and discovering and ameliorating any circumstances that may be triggering the headaches. Research confirms that NSAIDs, such as Ibuprofen, and acetaminophen are effective in reducing headache symptoms. Patients with chronic tension-type headache should limit their use of analgesics to two times weekly to prevent the development of chronic daily headache. Repeated use of analgesics, especially ones containing caffeine or butalbital, can lead to "rebound" headaches as each dose wears off and patients then take another round of medication. Common features of chronic daily headache associated with frequent analgesic use are early morning awakening with headache, poor appetite, nausea, restlessness, irritability, memory or concentration problems, and depression. If the patient requires analgesic medication more frequently, adjunctive headache medications can be initiated. Smoking cessation is an important issue to address in patients with chronic tension-type headache. The number of cigarettes smoked has been "significantly related" to the headache index score and to the number of days with headache each week.
An 88-year-old woman with osteoporosis sustained a hip fracture after falling. The fracture was surgically treated, and she was discharged to the inpatient rehabilitation unit. Her main complaint now is leg pain and numbness. On examination, you find hamstring and ankle weakness, an absent ankle reflex, and numbness on the posterolateral leg. Hip flexion, hip abduction, and knee extension strength is intact. Injury to which of the following nerves is most likely causative? Femoral Obturator Sciatic Superior gluteal
C- Sciatic The hip is a very common site for osteoporotic fractures, especially in an older woman. Hip dislocation or fracture is a common cause of compressive sciatic neuropathy. Other causes include prolonged bed rest, piriformis syndrome, and pelvic masses. Proximal sciatic neuropathy results in a wide array of symptoms, including sensory changes in the peroneal, tibial, and sural distributions (medial lower leg and arch of foot are likely spared due to saphenous innervation); absent ankle, decreased hamstring, and preserved knee reflexes; local pain that radiates through the posterior thigh and leg; and weakness in most of the leg EXCEPT for hip flexion and extension (femoral and gluteal nerve innervation), hip abduction and adduction (superior gluteal (D) and obturator (B) nerve innervation), and knee extension (femoral nerve (A) innervation). Electrodiagnostics (EMG and nerve conduction studies) are helpful in distinguishing sciatic neuropathy from L5 or S1 radiculopathy.
A 32-year-old man is brought to the emergency department after being the unrestrained passenger in a motor vehicle collision. His Glasgow coma score on scene was 6 and he was intubated for airway protection. On arrival, his vital signs are T 36.5°C, HR 40, BP 180/110. His physical exam is notable for a fixed and dilated left pupil. Which of the following is the most likely cause of this patient's physical exam findings? Central transtentorial herniation Tonsillar herniation Uncal transtentorial herniation Upward posterior fossa herniation
C- Uncal transtentorial herniation Brain herniation occurs as a result of increased intracranial pressure (ICP). The cranial vault has a fixed volume due to the rigidity of the skull bones. As such, the contents of the cranial vault exist in a state of volume equilibrium, such that an increase in the volume of one of the constituents must be compensated for by a decrease in the volume of another (Monro-Kellie doctrine). Increase in the blood constituent due to hematoma formation leads to an increase in the intracranial pressure, which will push a portion of the brain tissue out of the fixed cranial vault in an attempt to restore balance. Brain herniation can occur in multiple ways, including central transtentorial, tonsillar, uncal transtentorial, and upward posterior fossa herniation. Uncal transtentorial herniation occurs when the uncus of the temporal lobe is pushed inferiorly through the medial edge of the tentorium. This leads to compression of parasympathetic fibers running with the third cranial nerve resulting in a fixed and dilated pupil due to unopposed sympathetic tone.
A 24-year-old woman presents to the emergency department with a headache and receives a lumbar puncture. She is eventually discharged home in improved condition, but returns 24 hours later with a worsened headache, now throbbing in nature, which is worse in the standing position and relieved in the supine position. Which of the following reduces the risk of post-lumbar puncture headache? Inserting the needle bevel perpendicular to the spine Lying supine for one hour after the lumbar puncture is completed Using a higher gauge needle Using a Quincke needle
C- Using a higher gauge needle Post-lumbar puncture headache is the most common complication of a lumbar puncture (LP). The headache usually presents within the first 48 hours after LP and tends to be worsened by standing up and improved by lying down. The exact etiology is unclear, but may be related to the persistent leak of cerebrospinal fluid from the dural puncture site. Post-LP headache is generally benign and self-limiting within 24 to 48 hours, but can in some cases be debilitating. Bed rest and intravenous caffeine have been shown to improve symptoms, as has epidural blood patching, though the invasiveness of this procedure leads most providers to reserve it only for the most intractable and debilitating cases. Prevention of post-LP headache has been the subject of much research, with mixed and sometimes inconsistent results. Modern evidence-based strategies for prevention include the use of a higher gauge spinal needle (which corresponds to a smaller caliber needle), orientation of the needle's bevel parallel to the spine, use of a non cutting needle like the pencil-point Whitacre or Sprotte models, and reinsertion of the stylet prior to needle removal.
A 45-year-old woman presents to the ED reporting 1 day of vision loss in her left eye associated with a left retro-orbital headache. She reports no trauma or preceding illness. On exam, her vital signs are T 36.8°C, BP 112/80 mm Hg, and HR 74 bpm. Visual acuity is 20/20 in the right eye, 20/400 in the left eye, and 20/40 using both eyes. She has a left-sided afferent pupillary defect. Visual field testing reveals left-sided central vision loss. Which of the following is most accurate regarding her condition? Strict blood glucose control reduces the likelihood for future recurrences The diagnosis is confirmed by measurement of an intraocular pressure > 20 mm Hg The diagnosis is made by magnetic resonance venography The syndrome is associated with multiple sclerosis Therapy should be aimed at removing the acute obstruction of the ophthalmic artery
D- The syndrome is associated with multiple sclerosis The patient's exam is consistent with optic neuritis, an acute monocular loss of vision caused by focal demyelination of the optic nerve. Most cases are retrobulbar and do not involve any visible changes on funduscopy (especially during an acute episode). But on occasion and with more protracted cases, optic disk pallor may be seen. However, an afferent pupillary defect is always present. Approximately 30% of patients presenting with acute optic neuritis develop multiple sclerosis (MS) within 5 years. The classic clinical syndrome of MS consists of recurring episodes of neurologic symptoms that rapidly evolve over days and slowly resolve.
A 28-year-old woman complains of onset of lower back pain that began two days ago. The pain radiates down both legs. On exam, she has 3/5 strength bilaterally, decreased sensation from her waist distally, decreased patellar reflexes, and a distended urinary bladder. An MRI of her spine reveals no masses. Which of the following is the most likely diagnosis? Guillain-Barré syndrome Spinal epidural abscess Syringomyelia Transverse myelitis
D- Transverse myelitis Transverse myelitis is an acute spinal cord disorder characterized by paraplegia, a transverse level of sensory impairment, and sphincter disturbance. The specific etiology is unknown, although it is noted to follow a viral infection in 30% of patients and is commonly referred to as postinfectious myelitis. Patients often complain of back pain and may have a low-grade fever, raising the concern for an epidural abscess. An MRI is usually performed to rule out compressive lesions of the spine. Despite the absence of evidence, most sources still recommend high-dose steroids as first-line treatment.
A 45-year-old man with a history of alcohol use disorder presents with numbness and weakness of the left hand. He states he slept on a bench last night and awoke this morning with the symptoms. Physical examination reveals decreased sensation over the first, second, and third digits and a wrist drop is present. What management is indicated? CT of the cervical spine MRI of the brain Noncontrast CT scan of the head Wrist splint and follow up with neurology
D- Wrist splint and follow up with neurology This patient presents with a radial nerve palsy likely caused by direct compression and should have a wrist splint placed and given follow up with a neurologist. The radial nerve arises from the C5-T1 roots, exits the brachial plexus, and passes into the spiral groove behind the proximal humerus. It bifurcates at the antecubital fossa. This nerve controls extension of the fingers, thumb and wrist. Compression of the radial nerve in the axilla occurs secondary to the improper use of crutches or from an extended period of unconsciousness with prolonged compression. This pathology is typically called a Saturday night palsy. Patients with radial nerve palsy present with weakness in extension of the fingers and wrist. Spontaneous recovery often occurs but may take 2-4 months. During this time, the wrist should be splinted with 60 degrees of volar extension in order to prevent atrophy and contractures.
A 37-year-old man with a history of obesity and epilepsy presents to the primary care office. He takes phenytoin 300 mg twice daily. His vital signs are BP 108/69 mm Hg, HR 67 bpm, RR 15 breaths/min, T 98.2°F, and oxygen saturation 98% on room air. The patient states he has experienced migraine headaches for years. He says he has migraines an average of nine times per month. He describes his migraines as a unilateral, pounding sensation behind one of his eyes that is typically associated with nausea and sensitivity to light. At his last visit, you discussed lifestyle modifications, and the patient states he followed the modifications for months without improvement of his headaches. The patient would like to be started on prophylactic medication at this time. Which of the following is the best medication for this patient? Botulinum toxin Ergotamine Metoprolol Sertraline Topiramate
E - Topiramate Migraine headache is a disorder of recurrent attacks of unilateral, throbbing head pain that may or may not be associated with other neurological symptoms. Nausea and photophobia are commonly associated with migraine headaches. Migraine is a syndromic disorder of the brain that is, in most instances, inherited. The most common triggers include emotional stress, hormones in women, hunger, weather, sleep disturbances, odors, and neck pain. Neuroimaging is not necessary in most patients with migraine. Diagnosis is made clinically based on the patient's symptoms and history. Migraine headache attacks last anywhere between 4 and 72 hours, are unilateral, have a pulsatile quality, and are aggravated by physical activity. Either nausea or vomiting (or both) and photophobia or phonophobia are common during attacks, as well. More than four migraines per month or migraines that last longer than 12 hours and diminish a patient's quality of life despite acute treatment qualify patients for migraine prophylactic therapy. While several classes of medication can be used for migraine prophylaxis, the choice should be individualized according to patient-specific comorbid conditions and values. Topiramate is an anticonvulsant and is also indicated as a prophylactic medication for episodic migraines in patients with a history of seizure, thus is the best option for this patient.
