Neuro Rx Review
A 30-year-old man comes to the clinic because of progressive weakness and imbalance when walking for the past several months. Neurologic examination reveals repetitive, rhythmic plantar flexion on sudden dorsiflexion of the foot. Which set of findings in the table is most likely to be seen on neurologic examination?
Clonus involves involuntary muscle contractions, where a sustained clonus of five or more beats is considered abnormal. UMN lesions can cause clonus. UMN lesions are characterized by - clonus -increased deep tendon reflexes -increased tone -normal muscle bulk -weakness -absent fasciculations -absent atrophy -upgoing toes on Babinski sign
A 32-year-old woman comes to the emergency department because of vision loss in the left eye that began 45 minutes ago and has rapidly progressed. She recalls a previous episode of double vision that resolved without treatment 3 years ago and an episode of mild bilateral leg weakness and numbness 7 years ago. Her vital signs are within normal limits. Physical examination reveals a left afferent pupillary defect. Visual acuity in the left eye is 20/200. MRI of the brain reveals periventricular white matter plaques. Which of the following cells are primarily damaged in this patient's most likely diagnosis? A. Astrocytes B.Ependymal cells C.Microglia D.Oligodendrocytes E.Schwann cells
MS is a CNS demyelinating disorder in which MRI typically reveals periventricular white matter plaques. MS likely involves an antibody attack on oligodendrocytes. If the MRI is nondiagnostic, a lumbar puncture may be obtained, revealing increased IgG oligoclonal bands in the cerebrospinal fluid (CSF) in most patients with MS.
A 38-year-old woman comes to her primary care doctor because of a 4-month history of dizziness and a buzzing sound in her right ear. The dizzy spells last for 1 to 2 hours and she feels like the room is spinning; spells are sometimes accompanied by nausea and vomiting. Also during these episodes she experiences tinnitus and ear pressure, worse on the right side. Physical examination reveals that air conduction is greater than bone conduction in both ears. However, when a tuning fork is placed on her forehead, she says that the sound is better heard on the left. During these episodes, she notes her right ear "feels full."
Meniere disease 1. Sensorineural neural hearing loss (good ear > right ear) (air conduction > bone conduction) 2. Vertigo 3. Tinnitus Etiology: increase in volume of endolymph (due to increased production or decreased excretion)
What is the triad of congenital toxoplasmosis?
The classic triad of congenital toxoplasmosis is chorioretinitis, hydrocephalus, and intracranial calcifications.
What type of bacteria are strep pneumo, n meningitidis, h. influenzae, and listeria?
strep pneumo- gram positive, lancet shaped, diplococci staph a- gram positive cocci h influenzae- gram negative rods; encapsulated coccobacillus that requires factors V and X to successfully culture on chocolate agar e. coli- gram negative, lactose fermenting listeria- gram positive rods; beta hemolytic
A 20-year-old woman with a mild intellectual disability comes to the clinic for a routine checkup. Medical history includes a heart tumor that spontaneously regressed in childhood. Skin examination reveals an oval-shaped, slightly depigmented nevus on the lower back and an angiofibroma on the forehead. A previous MRI shows multiple nodules of glial proliferation in the basal ganglia, ventricles, and cortex. A. Bilateral hearing loss B.Central scotoma C.Glaucoma D.Retinal detachment E.Seizures F.Severe sun sensitivity
-seizures The patient's mild intellectual disability combined with the cutaneous findings, MRI results, and history of rhabdomyoma that regressed during childhood are indicative of tuberous sclerosis. Tuberous sclerosis is an autosomal dominant disorder affecting tuberin and hamartin proteins, which regulate cellular growth and differentiation. Two gene loci for tuberous sclerosis have been identified on chromosomes 9 and 16. Tuberous sclerosis has a variety of manifestations: seizures, benign hamartomas, subependymal brain tubers, intellectual disability, renal angiomyolipomas, cardiac rhabdomyomas, astrocytomas, pulmonary lymphangioleiomyomatosis, and cutaneous manifestations (eg, hypopigmented ash-leaf spot, shagreen patch, and facial angiofibromas).
Biopsy findings of: 1. Glioblastoma multiforme 2. Medulloblastomas 3. Meningiomas 4. Oligodendrogliomas
1. Glioblastoma multiforme - irregular ring-enhancing mass 2. Medulloblastomas Homer-Wright rosettes and small, blue cells. 3. Meningiomas psammoma bodies (laminated califications) + spindle cells in a concentric arrangement 4. Oligodendrogliomas - round nuclei with clear cytoplasm, producing a "fried egg" appearance with a "chicken wire" capillary pattern.
A 2-year-old boy is brought to his pediatrician by his parents because he has become "cross-eyed" over the past 2 months. Physical examination reveals strabismus and the finding shown in the image. He is found to have an eye tumor. The gene causing this child's most likely diagnosis has which of the following normal functions? A. Prevents cell-cycle progression past the G1/S checkpoint B.Prevents cell-cycle progression past the G2/M checkpoint C.Prevents metaphase-to-anaphase transition D.Promotes DNA damage repair E.Regulates apoptosis and angiogenesis
A Retinoblastoma can present in infants with strabismus and lack of red reflex in one or both eyes. Loss of function of both copies of the RB1 gene results in retinoblastoma. The RB1 gene codes for a protein that normally binds the E2F complex, preventing the cells from progressing past the G1/S restriction point in quiescent cells.
What are biochemical changes in Alzheimers?
AD is characterized by low levels of acetylcholine, decreased acetylcholinesterase, and reduced expression of nicotinic and muscarinic receptors. AD presents with an insidious loss of short-term memory, executive dysfunction, and impaired visuospatial skills.
A 74-year-old patient comes to the clinic reporting an increase in the number of times he wakes up each night. A sleep study shows markedly decreased total sleep time and diminished rapid eye movement sleep time. Which of the following is most likely responsible for the patient's sleep study results? A.Decrease in acetylcholine B.Decrease in dopamine C.Decrease in norepinephrine D.Decrease in serotonin E.Increase in serotonin
Acetylcholine in the reticular formation induces REM sleep, but levels of acetylcholine decrease with age. Therefore elderly patients who have naturally decreased levels of acetylcholine typically notice a reduction in REM sleep, total sleep time, and delta sleep. Patients may also report longer, more frequent night time awakenings. Decrease in dopamine and norepinephrine would promote sleep. Increase in serotonin would promote sleep. Decrease in serotonin would cause a decrease in the amount of time spent in non-REM sleep.
A 67-year-old man comes to the emergency department with new-onset neurological symptoms. He has a history of hyperlipidemia and hypertension and has a 50-year smoking history. A CT of the emergent head shows an ischemic area on the lateral aspect of his left frontal and temporal lobes. Which of the following symptoms is this injury most likely to cause?
An ischemic lesion affecting the lateral frontal and temporal lobes is likely due to a lesion in the middle cerebral artery (MCA). The MCA supplies the lateral aspect of the frontal, temporal, and parietal lobes. If the right hemisphere is compromised, it results in left-sided weakness and sensory loss, gaze deviation to the right, and neglect of the left visual space. If the left hemisphere is compromised, the patient would have similar findings, but on the right side. Because the language centers of the brain are typically in the left hemisphere, an ischemic lesion in the MCA often adversely affects speech. The MCA supplies both the Broca and Wernicke speech areas. An injury to the MCA can produce either expressive aphasia (if the Broca area is injured) or receptive aphasia (if the Wernicke area is injured). Additional impairments may include difficulty with reading, writing, and calculation. (Progressive lack of empathy is a symptom of behavioral variant frontotemporal dementia, in which patients have significant atrophy of the frontal and temporal lobes. This patient's lesion is only on the left, while behavioral variant frontotemporal dementia would affect the bilateral frontal and temporal lobes.)
A 3-year-old girl is brought to the physician for a follow-up examination. She had two tonic-clonic seizures 2 weeks ago. She has a history of feeding difficulties and global developmental delay. Physical examination is notable for microcephaly, paucity of speech, and sudden outbursts of laughter. Which of the following is the etiology of this child's most likely diagnosis?
Angelman syndrome presents with feeding intolerance, developmental delay, seizure, hyperactivity, sudden outbursts of laughter, microcephaly, and movement or balance disorders. Angelman syndrome is caused by an absence or deletion of the maternal gene in a region where the paternally inherited gene is imprinted.
During an experiment, high doses of drug X are given intravenously to an anesthetized animal and an increase in blood pressure is seen. Several days later when the animal's blood pressure has stabilized, drug Y is administered, followed by administration of drug X. In this second experiment, the researchers note that the animal's mean arterial pressure is decreased. A. Drug X = acetylcholine; Drug Y = neostigmine B.Drug X = epinephrine; Drug Y = phentolamine C.Drug X = isoproterenol; Drug Y = atropine D.Drug X = norepinephrine; Drug Y = propranolol E.Drug X = phenylephrine; Drug Y = hexamethonium
B. Epinephrine is an agonist at α1-, α2-, β1-, and β2-receptors. At high doses, the effects of epinephrine to stimulate β1-receptors in the heart and α1-receptors in the vasculature lead to an increase in blood pressure. When phentolamine, a reversible antagonist at α1- and α2-receptors, is added, the effects of epinephrine-induced vasoconstriction via α1-receptors are blocked. This essentially converts epinephrine into a β1-, β2-agonist. The effect of unopposed β2-receptor activation will lead to vasodilation and a drop in mean arterial pressure. This effect of α1-antagonists to block epinephrine-induced vasoconstriction is often referred to as "epinephrine reversal."
An 18-year-old woman comes to clinic with progressive hearing loss and tinnitus. She has had increasing difficulty hearing her professors in college classes during the past few months. She has bilateral vestibular schwannomas. What does she have?
Because her tumor is bilateral, it is most likely a manifestation of an inherited condition such as neurofibromatosis type 2 (NF2). NF2 is also associated with an increased risk for developing cataracts, causing patients to present with blurry vision. An abnormal Rinne test would indicate conductive hearing loss, not sensorineural as in this patient.
A 47-year-old-woman presents to the clinic with the new onset of a red eye. She noticed it last night before bed and has not seen any change in color or size since its onset. She felt sick yesterday and had multiple bouts of emesis but feels fine today. Pulse is 78 beats/min and blood pressure is 120/80 mm Hg. Visual acuity is normal. Examination findings are as seen in the image. (whites of eye are completely red)
Brief increase in venous pressure This patient has likely had a subconjunctival hemorrhage, as evidenced by the blood localized to the conjunctiva seen on examination, recent history of vomiting, and lack of trauma or visual changes. A subconjunctival hemorrhage occurs as the capillaries within the conjunctiva are damaged, leading to pooling of blood in between the sclera and conjunctiva. The characteristic finding is a localized spot of blood where the bulbar conjunctiva would normally be white, without symptoms of vision changes or infection. The most common mechanism for the development of a spontaneous subconjunctival hemorrhage is a brief increase in the venous pressure leading to capillary damage in the conjunctiva.
A 42-year-old woman is brought to the emergency department with a 1-day history of paralysis that started in her legs and has progressed to her upper extremities and face. Medical history is notable for a diarrheal illness 3 weeks ago. Physical examination reveals that motor strength is decreased in her facial muscles and extremities, and ankle-jerk and knee-jerk reflexes are diminished bilaterally. Cerebrospinal fluid analysis shows increased protein and normal cell counts. What does she have?
GBS is an acute monophasic paralyzing illness that manifests with ascending paralysis 2 to 4 weeks after a respiratory or GI illness. Activated T cells in GBS attack and demyelinate Schwann cells, which normally function to myelinate axons in the peripheral nervous system.
A 35-year-old woman comes to the emergency department with dizziness, nausea, and hearing loss in the left ear for 1 day. She says she feels off-balance and feels like the room is spinning. She had viral gastroenteritis last week that resolved. On physical examination, her eyes slowly drift to the left before quickly jerking to the right. A vibrating tuning fork is placed in the center of the forehead, and the patient hears the vibration best in the right ear. The tuning fork is then placed outside of the ear and then onto the mastoid bone, and the patient hears the vibration better when the prongs are placed outside the ear bilaterally, but both air conduction and bone conduction are reduced in the left ear as compared to the right ear. Which of the following is the most likely mechanism behind this patient's findings? A. Bacterial infection of the middle ear B.Cerebellar hemorrhage C.Herpes simplex virus infection D.Inflammation of cranial nerve VIII E.Lateral medullary infarction F.Tympanic membrane rupture
D Labyrinthitis presents with unilateral sensorineural hearing loss, vertigo, and a horizontal nystagmus. Labyrinthitis is caused by unilateral inflammation of the vestibular portion of CN VIII and often presents shortly after a viral infection.
A 3-year-old boy is brought to the pediatrician's office by his mother for concerns over a waddling gait and frequent falls when walking. Physical examination reveals enlarged calves. The child uses his hands and arms to push himself to stand from a seated position. Which of the following disorders shares the same inheritance pattern as the most likely diagnosis in this patient? A.Cystic fibrosis B.Hemochromatosis C.Hemophilia A D.Marfan syndrome E.Neurofibromatosis type 1
DMD is characterized by difficulty walking, calf pseudohypertrophy, and a positive Gower sign. Both DMD and hemophilia A are X-linked recessive disorders because the genes that cause these diseases are located on the X chromosome, and the disease is most commonly passed from carrier mothers to their sons. Cystic fibrosis and hemochromatosis are autosomal recessive disorders. Marfan syndrome and neurofibromatosis type 1 are autosomal dominant disorders.
What does disruption of mesocortical, mesolimbic, nigrostriatal, and tuberinfundibular tract cause?
Disruption of the mesocortical tract (cognition) causes decreased cognitive function, avolition, and alogia Disruption of the mesolimbic tract causes decreased interest in positive rewards and a decrease in the positive symptoms of schizophrenia Disruption of the nigrostriatal tract causes Parkinsonian movement dysfunction and tardive dyskinesia Dsinhibiting the tuberoinfundibular pathway manifests with amenorrhea and galactorrhea.
A 69-year-old woman comes to the office because of a 6-month history of a right-hand tremor and slowed movement. She has to hold her hand to prevent it from shaking at rest, but the tremor resolves with intentional movement. Her family members have commented on her slower movements while walking or performing activities. Which of the following neurotransmitters is most likely dysregulated in this patient?
Dopamine
Lewy bodies are
Eosinophilic cytoplasmic inclusions
A 60-year-old man comes to the physician because of a persistent headache that has worsened over the past several months. He also reports worsening erectile dysfunction and says that he repeatedly collides with door frames because he cannot see out of the corners of his eyes. Physical examination reveals bilateral peripheral vision deficits. Which of the following additional symptoms is the patient most likely to report?
Gynecomastia (man boobs) This 60-year-old man's symptoms of persistent headache, worsening erectile dysfunction, clumsiness, and deficits in peripheral vision indicate the presence of a prolactinoma, the most common tumor of the pituitary gland. Compression of the optic chiasm by pituitary tumors characteristically causes bitemporal hemianopia. This lesion often causes patients to miss objects that present in their temporal fields, such as door frames and cars in adjacent lanes. Furthermore, a chronic headache that increases in severity is a sign of an intracranial tumor. Hypersecretion of prolactin by a prolactinoma can cause decreased libido in men and women. It can also cause erectile dysfunction and gynecomastia in men, while in women it can cause galactorrhea, amenorrhea, and infertility.
A 53-year-old woman comes to the clinic for a hearing test. During the test, headphones are placed over her ears and tones of varying frequency are played. She indicates when each tone is heard and in which ear she hears it. Which of the following mechanisms is most involved in processing the high-frequency tones in this test? A. Bending of stereocilia found at the base of the cochlea B.Depolarization of hair cells within the utricle C.Movement of stereocilia embedded in Reissner membrane D.Transmission of vibrations along the tensor tympani, activating the organs of Corti E.Vibration of the stapes against the round window
High frequency tones are processed in the ear through bending of stereocilia found at the base of the cochlea. The sound wave travels down the auditory canal and vibrates the tympanic membrane, which in turn vibrates the malleus, incus, and stapes. The stapes vibrate against the oval window and cause a fluid wave in the cochlear scala vestibuli. The scala vestibuli becomes the scala tympani as it turns at the apex of the cochlea. The fluid wave moving through these channels pushes the basilar membrane, causing bending of the stereocilia atop hair cells and subsequent depolarization. Nerve signals travel down afferent fibers of the cochlear nerve to the brain. Different areas of the cochlea activate to different frequencies. High frequencies are detected by the base of the cochlea while low frequencies are detected at the apex.
A 60-year-old woman comes to the emergency department with a sudden-onset severe headache and right hemiparesis after an episode of emesis early this morning. She has a history of rheumatoid arthritis, hypertension, and hyperlipidemia. Which of the following is the most likely cause of this patient's pathology? A. Amyloid angiopathy B.Glioblastoma multiforme C.Hypertension D.Rupture of the bridging veins E.Rupture of the middle meningeal artery F.Ruptured berry aneurysms
IPH presents suddenly in patients, causing headache, vomiting, decreased level of consciousness, and increased intracranial pressure. IPH is most commonly caused by systemic hypertension.
Normal pressure hydrocephalus
Increased CSF due to decreased reabsorption by arachnoid granulations, resulting in dilated ventricles type of communicating hydrocephalus
A 53-year-old man comes to the clinic because he has been unable to move the left and right sides of his face over the past 4 days. One month ago he had a red rash with a central clearing on his right hip. Which of the following clinical events most likely occurred in the man's recent past?
Lyme disease may manifest with a bilateral facial palsy. These patients may describe a recent tick bite, an erythematous rash with central clearing (erythema migrans, see image), or new polyarthritis. Lyme disease is caused by transmission of the spirochete Borrelia burgdorferi from the bite of the Ixodes tick.
A 44-year-old woman who underwent a cholecystectomy 2 hours ago is being evaluated due to double vision and difficulty speaking and breathing. The surgery was performed under general anesthesia and was uneventful. On physical examination, there is bilateral ptosis, which is worse on the right, and labored breathing. An ice pack is applied to her right eyelid, and the ptosis improves after several minutes. She reports having had a few episodes of double vision during the last 2 months, usually at the end of a long day. These didn't last very long, however, and she never sought medical attention. Which of the following is the most likely cause of this patient's symptoms? A, Antibodies to acetylcholine receptors B.Antibodies to presynaptic calcium channels C.Demyelination of the central nervous system D.Demyelination of the peripheral nervous system E.Disruption of oculosympathetic chain F.Irritation of trigeminal nerve
Initial presentation of myasthenia gravis involves painless weakness of the ocular and bulbar muscles that worsens with activity and improves with rest. Patients can go undiagnosed and have the full disease manifest following surgery, due to the use of neuromuscular blocking agents. Myasthenia gravis is an autoimmune disease resulting from antibodies to nicotinic acetylcholine receptors at the neuromuscular junction. The ice pack test can aid in the diagnosis of myasthenia gravis, as cold temperatures inhibit acetylcholinesterase.
A group of researchers is studying regional specifications of the developing brain. For the study, a rat embryo is injected with a drug that inhibits the area of the brain responsible for development of the midbrain. Which of the following structures is most likely affected by this drug?
Mesencephalon The telencephalon is the rostral subdivision of the prosencephalon and gives rise to the cerebral hemispheres, hippocampus, basal ganglia, and olfactory bulb. The diencephalon is the caudal subdivision of the prosencephalon and gives rise to the thalamus and hypothalamus. The mesencephalon contains the progenitor cells of the midbrain. The metencephalon is the rostral subdivision of the rhombencephalon and gives rise to the cerebellum and pons. The myelencephalon is the caudal subdivision of the rhombencephalon and gives rise to the medulla.
Prosopagnosia
PCA infarct inability to recognize faces
A 45-year-old man with type 2 diabetes mellitus presents to his physician for a wellness evaluation. The patient does not report any changes in vision, difficulty with gait, or injuries to the feet. Fundoscopic examination is unremarkable. On neurologic examination, there is absent vibratory sensation in the feet on tuning fork test and diminished ankle-jerk reflexes bilaterally. Motor strength is intact. What is damaged in diabetic neuropathy? Pacinian vs Meissner vs Merkel vs Ruffini vs free nerve endings
Pacinian corpuscles- vibration, pressure, and tension (damaged in diabetic neuropathy) Meissner- light tough/vibration Merkel nerve- deep touch/pressure Ruffini- stretch/transducing pressure free nerve endings- pain/temperature
A 10-year-old boy is brought to the pediatrician with 1 month of headache, nausea, and vomiting. The headaches are dull, worse in the morning, and not effectively relieved by acetaminophen or ibuprofen. He does not report snoring. On examination, the physician notes impairment of upward gaze. Results of fundoscopic examination are shown. MRI of the brain after contrast reveals an abnormal mass with calcifications located at the third ventricle. Which of the following is the most likely cause of this patient's symptoms? A. Craniopharyngioma B.Epidermoid cyst C.Hypothalamic hamartoma D.Pineal tumor E.Pituitary adenoma
Pineal masses typically manifest with symptoms of increased ICP and Parinaud syndrome, a condition characterized by vertical gaze palsy and pupil abnormalities. MRI with contrast will show an abnormal mass located in the posterior third ventricle. The patient's symptoms of headache, nausea, and vomiting combined with fundoscopy depicting swelling of the optic nerve head (papilledema) are strongly suggestive of increased intracranial pressure (ICP). His MRI shows an abnormal mass with punctate calcifications located in the posterior aspect of the third ventricle, which is consistent with a pineal mass (indicated by arrows in the images). This is a rare condition that accounts for only 1% of primary brain tumors. Calcifications are typically visualized on noncontrast CT and are not visible on the postgadolinium MRI images. Pineal masses can manifest with symptoms of increased ICP, such as headache, nausea, and vomiting, as a result of obstruction of cerebrospinal fluid flow through the cerebral aqueduct. Pressure on the pretectal region of the midbrain may also result in Parinaud syndrome, a condition characterized by vertical gaze paralysis and pupil abnormalities.
A 40-year-old man is brought to the emergency department by his wife because he has become agitated and is unable to drink water. This follows a week-long illness, which included a low-grade fever with fatigue, sore throat, vomiting, headache, and photophobia. He and his wife were recently in Haiti, where they interacted with stray dogs and cats. Vital signs show a temperature of 38.9°C (102°F), pulse of 120/min, and respirations of 22/min. The patient is diaphoretic and drooling. He is unable to follow commands. His salivary glands are enlarged on palpation. Muscle tone and reflexes are increased bilaterally. This patient's most likely disease affects the central nervous system through which of the following mechanisms?
Rabies infection presents with photophobia, enlarged salivary glands, profuse salivation, and altered mental status. After direct inoculation, rabies virus binds to nicotinic acetylcholine receptors and travels to the central nervous system via retrograde axonal transport.
A 12-year-old boy is brought to the emergency department due to severe blistering on his face for 2 days. The blisters have gotten increasingly worse. He has a history of epilepsy and was started on a new seizure medication 1 week ago. This new medication blocks sodium channels. Temperature is 38°C (101.1°F). Physical examination reveals lesions of the genital, nasal, and oral mucosa and of the face as shown. Which of the following drugs was most likely prescribed to this patient? A. Ethosuximide B.Gabapentin C.Lamotrigine D.Lorazepam E.Phenobarbital
Several antiepileptic medications are characterized by severe blistering of the mucosal surfaces, potentially leading to epidermal necrosis; these drugs include lamotrigine, phenobarbital, phenytoin, and carbamazepine. Lamotrigine blocks sodium channels. Phenobarbital and ethosuximide may cause SJS but are not sodium channel blockers. Lorazepam and gabapentin neither block sodium channels nor cause SJS.
A 10-year-old girl is brought to the emergency department by her parents because of a worsening headache. She fell down the stairs at home last week but felt fine except for a scrape on her right knee. For the last 12 hours she has had a headache and has felt nauseous. On physical examination she is conscious but appears drowsy and is unable to answer detailed questions. What trauma type?
The imaging and clinical scenario are consistent with a subdural hematoma (SDH), consistent with her signs of increased intracranial pressure (nausea, drowsiness) after trauma. They present 1 to 14 days after the injury with progressively worsening symptoms of headache, increased intracranial pressure, personality changes, or focal neurologic signs as the hematoma slowly enlarges. SDH occurs when there is bleeding from the low-pressure bridging veins that traverse the subdural space to empty blood into the dural venous sinuses. This results in blood accumulation between the dura and arachnoid layers.
What does lacunar infract to following sites cause? A. Cerebellum B.Internal capsule C.Pons D.Temporal lobe E.Thalamus
The most common type of lacunar stroke is a pure motor stroke. The typical site of injury is the posterior limb of the internal capsule. Hypertension and diabetes mellitus are two risk factors for the development of lacunar infarcts (ie, small-vessel strokes). An infarct in the cerebellum is most likely to cause dysmetria, ataxia, and/or intention tremor. Pons is most likely to cause dysarthria and clumsiness of the hand. Infarction to the superior temporal lobe in the left hemisphere can cause Wernicke (receptive) aphasia, in which patients exhibit nonsensical fluent speech because they have difficulty comprehending language. A patient with an infarct in the thalamus likely would present only with sensory losses. The patient might report numbness and/or tingling on one side of the body (face, arm, leg, trunk). A thalamic infarct is unlikely to cause motor symptoms.
A 3-day-old male infant is brought to the clinic with eye swelling and discharge. The infant was born via normal spontaneous vaginal delivery at home; his mother did not receive prenatal care. Physical examination shows bilateral purulent ocular discharge, inflammation surrounding both eyes, and enlarged preauricular lymph nodes. A. Adenoviral keratoconjunctivitis B.Chlamydial conjunctivitis C.Congenital cataracts D.Gonococcal conjunctivitis E.Herpes simplex keratoconjunctivitis
This infant whose mother received no prenatal care is presenting with ocular swelling and discharge. Because the patient was delivered at home, it is very unlikely that he received erythromycin eyedrops and is likely suffering from infectious conjunctivitis. His presentation of bilateral purulent discharge and preauricular lymphadenopathy within 5 days postpartum is indicative of gonococcal conjunctivitis. Neonatal gonococcal conjunctivitis is caused by Neisseria gonorrhea, a gram-negative diplococcus that is acquired from the birth canal of an infected mother during birth. Gonococcal conjunctivitis has an early onset and can present anywhere from birth up to the fifth day of life. It presents with conjunctival injection, edema of the eyelids, severe bilateral purulent discharge, tenderness of the globe, and preauricular lymphadenopathy. Gonococcal conjunctivitis presents with conjunctival infection and mucopurulent discharge. It typically occurs from birth to around the fifth day of life.
A 59-year-old man comes to the emergency department with dizziness, vomiting, and a humming sound in his left ear. He has a history of poorly controlled hypertension and atrial fibrillation, for which he does not consistently take medication. Temperature is 37°C (98.6°F), pulse is 120/min, and blood pressure is 168/90 mm Hg. On physical examination, the patient is ataxic and falling toward his left side. Pain and temperature sensation are impaired along the right side of his body and the left side of his face. His right pupil is 5 mm in diameter, left pupil is 2 mm, and there is drooping of the left eyelid. He is unable to move the left side of his face. Which of the following areas is rostral (superior) to the level of the lesion most likely affecting this patient? A. Hypoglossal trigone B.Nucleus ambiguus C.Nucleus solitarius D.Red nucleus E.Vestibular nucleus
This patient has a history of hypertension and presents with high blood pressure. He is likely experiencing lateral pontine syndrome with tinnitus, left-sided Horner syndrome, loss of pain and temperature sensation to the right side of his body but the left side of the face, dizziness, vomiting, and ataxia. This syndrome is caused by a pontine stroke from occlusion of the anterior inferior cerebellar artery (AICA). Occlusion of the AICA prevents blood flow to the pons and causes the symptoms seen here. Areas affected may include the vestibular nuclei (vertigo, vomiting), spinocerebellar tract (ipsilateral ataxia), spinothalamic tract (contralateral loss of pain and temperature sensation), spinal trigeminal nucleus (ipsilateral loss of pain and temperature sensation to face), facial nerve (ipsilateral facial paralysis), vestibulocochlear nerve (ipsilateral tinnitus), and descending sympathetic pathway (Horner syndrome). The red nucleus is located in the midbrain. Therefore, it is superior (rostral) to the lesion that is affecting this patient, which is localized to the pons. The red nucleus is involved in flexion of extremities. The vestibular nucleus is located in the pons and medulla. The nucleus ambiguus, hypoglossal trigone, and nucleus solitarius are located in the medulla.
What does open-angle glaucoma look like on fundoscopy?
This patient has glaucoma, most likely open-angle glaucoma, evident by the optic nerve cupping (cup/disc ratio of >50%) seen on fundoscopy. The cup is the white area in the center of the optic disc (see figure). A cup diameter that exceeds 50% of the disc diameter suggests glaucoma, reflecting the loss of vision-sensing neurons due to high intraocular pressure (IOP). Open-angle glaucoma usually presents asymptomatically, with the chronic loss of peripheral vision, but it can present with headaches and impaired adaptation to darkness.
What are PML symptoms?
This patient living with HIV presents with right-sided weakness and reduced vision in her left eye. These symptoms, combined with her MRI and her low CD4+ cell count, are consistent with progressive multifocal leukoencephalopathy (PML). PML typically manifests with rapidly progressive focal neurologic deficits without signs of increased intracranial pressure. Ataxia, aphasia, and cranial nerve deficits may also occur. Cerebrospinal fluid (CSF) analysis is often normal, although it can reveal the presence of myelin basic protein, which is due to demyelination caused by the JC virus. It can also show nonenhancing multiple white matter lesions that are hyperintense on T2-weighted sequences, indicated by the arrows.
A 77-year-old man presents to the clinic with complaints of trouble reading, developing gradually over the past year. He has increasing difficulty seeing things in the center of his vision; he no longer drives amid family concerns about his vision impairment. He is otherwise healthy. He has a 50-pack-year history of smoking. Visual acuity is decreased bilaterally, and formal testing shows severe loss of central vision with intact peripheral vision. Which of the following funduscopic findings is most likely in this patient? A. Arteriovenous nicking B.Cherry-red spot C.Cotton-wool spots D.Extracellular lipid deposits E.Flame hemorrhages F.Roth spots
This patient is likely suffering from dry age-related macular degeneration, evidenced by his central vision loss (with normal peripheral vision), gradual onset of symptoms, and smoking history. This is an extremely common cause of bilateral, insidious blindness in the elderly. Central vision loss with blind spots, called scotomas, is characteristic and often progresses for longer than a decade before stabilizing. This central vision loss occurs due to the involvement of the macula in disease progression. Fundoscopic exam in patients with dry age-related macular degeneration is likely to reveal extracellular lipid deposits, called drusen. Progressively increased drusen deposition can also lead to atrophy of the retinal pigment epithelium, which will appear as lighter pigmented regions near the macula.
A 69-year-old man comes to the clinic because of a 6-month history of progressive leg weakness and falling. During the last month he also has experienced intermittent double vision with droopy eyelids. He also complains of a dry mouth and constipation. His wife has noticed that his voice is slurred and more difficult to understand. On examination, he has mild ptosis of the left eyelid, but eye movements are normal. He has mild bilateral lower extremity muscle weakness that is more prominent in proximal muscles, but the muscles do not appear atrophied. Reflexes are absent throughout, but with brief muscle activation he is observed to have normal reflexes, but this only lasts for about 5 to 10 seconds. He says that he is otherwise healthy but has smoked 1 pack of cigarettes per day since he was 19 years old. The physical examination is normal. An x-ray of the chest is shown. Further workup reveals metastases throughout the body. A. Antibodies against presynaptic voltage-gated calcium channels at the neuromuscular junction B.Autoantibodies to acetylcholine receptors at the neuromuscular junction C.Autoimmune disease with anti-double-stranded DNA, anti-DNA, and anti-Smith antibodies D.Inflammatory disorder of synovial joints with pannus formation E.Reactivation of a peripheral subpleural parenchymal lesion and hilar lymph nodes
This patient likely has Lambert-Eaton syndrome (LES), a paraneoplastic syndrome, given his x-ray of the chest showing a central lung cancer, metastases, proximal muscle weakness, decreased deep tendon reflexes (that improve with activity), and diplopia. Parasympathetic deficits, especially dry mouth and constipation, are common. Exercise-induced facilitation of reflexes is a unique diagnostic finding for LES. Patients typically have neurologic symptoms prior to the diagnosis of lung cancer. Small cell lung carcinoma (indicated by red box in the image) is a neoplasm of neuroendocrine Kulchitsky cells that frequently produces paraneoplastic syndromes, including ectopic production of ACTH and ADH. Small cell lung carcinoma is a neoplasm of neuroendocrine Kulchitsky cells associated with a number of paraneoplastic syndromes, including ectopic production of ACTH, ADH, and LES. LES is caused by antibodies against presynaptic calcium channels at the neuromuscular junction.
A 25-year-old woman comes to the clinic with difficulty walking for the past 2 days. Both legs feel heavy. She also reports numbness from the waist and down to both legs. She decided to come to the clinic when she also noticed difficulty emptying her bladder fully. Six months ago, she lost the vision in her left eye while on a trip to Europe. She never sought medical attention, and her vision returned to normal within about 2 weeks. She is aware, however, that when she takes a long, hot bath, the vision in her left eye is blurred but then resolves to normal after she cools down. On examination, she has bilateral leg weakness and sensory loss with hyperreflexia in both legs. She also has left optic disc pallor. A T2-weighted fluid-attenuated inversion recovery MRI is shown. Which of the following cerebrospinal fluid (CSF) findings would be seen in this patient's most likely diagnosis? A. Cytoalbuminologic dissociation B.Elevated lactate level C.High levels of clonal IgG antibodies D.Increased number of neutrophils E.Reduced glucose level
This patient likely has multiple sclerosis (MS). This is because of her presentation with central nervous system symptoms, including transverse myelitis (paraplegia, hyperreflexia, and bladder dysfunction) and optic neuritis. MS is also suggested by the recurrent episodes of left-eye blurred vision with heat exposure, called the Uhthoff phenomenon, the exacerbation of symptoms with increased body temperature (eg, hot bath, exercise). In addition, this patient's MRI demonstrated hyperintense signal abnormalities in the periventricular and subcortical white matter (indicated by the arrows), confirming MS as the diagnosis. Patients with MS may also present with optic neuritis (painful loss of vision resulting in Marcus Gunn pupils) and internuclear ophthalmoplegia. In patients with MS, CSF analysis will show high levels of clonal IgG antibodies, referred to as oligoclonal bands. The overall protein level is also elevated, especially during an MS relapse. The increased WBC count in CSF will show mostly T cells. Elevated lactate level, increased number of neutrophils, and reduced glucose level would be seen in bacterial meningitis, which presents with fever, nuchal rigidity, and altered mental status. Cytoalbuminologic dissociation is indicative of Guillain-Barré syndrome, which manifests with a symmetric ascending paralysis and absent reflexes.
An 43-year-old man living with HIV is brought to the physician by his caregiver because of significant cognitive and behavioral decline over the last 6 months. The patient has not had recent fevers, headaches, or motor or sensory changes. Recent CD4+ cell count was 150/mm3. His temperature is 37.0°C (98.7°F). The cerebrospinal fluid analysis shows an HIV viral load of 700 copies/mL. Which of the following central nervous system cell types has most likely become infected with HIV in this patient?
This patient living with poorly controlled HIV has experienced insidious onset of cognitive and behavioral decline but does not have a fever, headaches, or focal neurologic deficits. This should raise suspicion for HIV encephalopathy (HIV-associated dementia). HIV encephalopathy is classically seen in patients with a long history of poorly controlled HIV infection with CD4+ cell counts below 200. Cerebrospinal fluid analysis would typically reveal a high HIV viral load, and brain imaging scans might show nonspecific, diffuse cortical and subcortical atrophy. HIV encephalopathy is caused by infection of microglia in the brain. Microglia act as macrophages of the central nervous system (CNS). The histologic hallmark of HIV encephalopathy is the microglial nodule, largely consisting of multinucleated giant cells (indicated by the arrow in the image in the stem), which are formed by the fusion of HIV-infected microglial cells.
A 24-year-old woman comes to the clinic with 2 months of redness and chronic, dull, achy pain of the right eye. Medical history is significant for Crohn disease, for which she takes adalimumab. Examination reveals right-sided dilated ciliary vessels and inflammatory cells in the anterior chamber. Which of the following is the most likely diagnosis? A. Anterior uveitis B.Blepharitis C.Conjunctivitis D.Glaucoma E.Retrobulbar hematoma
This patient with Crohn disease most likely has anterior uveitis, which can be caused by trauma but is also associated with several systemic inflammatory syndromes, such as Crohn disease. On exam, the patient will present with ciliary vessel dilation, redness, and hypopyon (WBCs in the anterior chamber). Patients with anterior uveitis often also present with consensual photophobia. This phenomenon is observed when light is shined into the unaffected eye, but it causes the affected eye to constrict as well, leading to pain.
A 73-year-old woman comes to the clinic with extremely painful blisters on her head. She is undergoing chemotherapy to treat late-stage breast cancer. Physical examination shows a vesicular rash on the back of her head. Which of the following dorsal root ganglions is most likely associated with the patient's dermatologic lesions? A. C1 dorsal root ganglion B.C2 dorsal root ganglion C.C3 dorsal root ganglion D.C4 dorsal root ganglion E.C5 dorsal root ganglion
This patient's lesion location implies dermatome C2, meaning that latent VZV was reactivated in the C2 dorsal root ganglion (see figure). It can be described as the "posterior half of a skull cap." The C1 dorsal root ganglion is not associated with a dermatome, as there are no sensory roots exiting at C1. The dermatome associated with the C5 dorsal root ganglion covers the shoulders and outer part of the upper arm. The dermatome associated with the C3 dorsal root ganglion covers the neck. The dermatome associated with the C4 dorsal root ganglion covers the shoulder, collarbone, and shoulder blade.
A 43-year-old homeless man is brought to the emergency department via ambulance after being found unconscious in a nearby park. He is unarousable and has a blood alcohol concentration of 0.3%. He is admitted for hydration and nutritional supplementation. On awakening, he has concerning neurologic findings but the examination is otherwise normal. The serum electrolytes, glucose, blood urea nitrogen, creatinine, calcium, albumin, and hepatic transaminases are normal. An MRI of the head shows cerebellar atrophy. Which of the following would be a likely early sign of this patient's most likely disease? A. Abnormal finger-to-nose pointing B.Asterixis (predominantly related to abnormal ammonia metabolism and thus seen in chronic renal or liver failure) C.Hyporeflexia D.Tinnitus E.Unsteady heel-to-toe walking F.Vertigo
Unsteady heel-to-toe walking This patient's alcohol use and MRI showing cerebellar atrophy make the diagnosis of alcoholic cerebellar degeneration likely. It is characterized by initial lower extremity ataxia and gait impairment and later may show dysarthria, upper extremity ataxia, diplopia, or blurred vision. Alcoholic cerebellar degeneration targets the anterior and superior parts of the cerebellar vermis, which is responsible for axial and lower extremity coordination.
Bilateral lesions of the mammillary bodies cause
Wernicke-Korsakoff syndrome, with ataxia, confusion, and ophthalmoplegia.
This patient with RIGHT conductive hearing loss would be expected to have
bone conduction greater than air conduction on Rinne testing on the right side with right lateralization of the Weber test (louder on the right side).
Rabies is a
enveloped, single-stranded RNA virus. Rabies infection manifests early with a nonspecific prodrome, followed by a long incubation that slowly progresses to severe encephalitis.
What are calcium channel anti-epileptics?
ethosuximide gabapentin + pregabalin levetiracetam
