Step 2 Capstone Questions Head and Neck

Four days after undergoing open reduction and internal fixation of a fracture of the right femur sustained in a motor vehicle collision, a 47-year-old man continues to have agitation and confusion despite treatment with haloperidol. He has mild hypertension. Other medications include acetaminophen, atenolol, and prophylactic subcutaneous heparin. His temperature is 37.2°C (99°F), pulse is 98/min, respirations are 24/min, and blood pressure is 168/98 mm Hg. During the examination, he is uncooperative and refuses to answer questions. Neurologic examination shows tremulousness and no focal findings. He is oriented to person but not to place or time. A CT scan of the head shows no abnormalities. Which of the following is the most likely cause of these findings? (A) Adverse effect of medication (B) Alcohol withdrawal (C) Fat emboli (D) Sepsis (E) Subdural hematoma

*Answer B is correct.* Agitation, confusion, and tremulousness are consistent with a diagnosis of alcohol withdrawal. Tachycardia and elevated blood pressure are common in withdrawal, but may be abated by antihypertensive medicine (e.g., atenolol). Symptoms of withdrawal can last up to 7 days. Answer A is incorrect. Haloperidol administration would not explain the patient's symptoms. Haloperidol can cause parkinsonism (tremor, rigidity, hypokinesia, and postural instability) because of its anti-dopaminergic properties. Rarely, it can cause neuroleptic malignant syndrome, characterized by hyperthermia, delirium, rigidity, and autonomic instability. Answer C is incorrect. Fat embolism typically occurs after trauma to long bones. Findings include confusion, shortness of breath, hypoxemia, and petechial rash (often associated with anemia and thrombocytopenia). Answer D is incorrect. Sepsis is often associated with fever, altered mentation, and hypotension. Answer E is incorrect. A subdural hematoma should be visible by CT. The patient in this vignette has a normal head CT scan.

A previously healthy 22-year-old college student is brought to the emergency department by her parents 20 minutes after they observed her having a seizure. After the seizure, she was confused and had difficulty thinking of some words. She has had a headache, cough, and fever for 3 days treated with acetaminophen and dextromethorphan. Her temperature is 38.9°C (102°F). Neurologic examination shows diffuse hyperreflexia. On mental status examination, she is confused and has short-term memory deficits. She has difficulty naming objects and makes literal paraphasic errors. An MRI of the brain shows bitemporal hyperintensities. A lumbar puncture is done; cerebrospinal fluid analysis shows an erythrocyte count of 340/mm3, a leukocyte count of 121/mm3, (88% monocytes), and a protein concentration of 78 mg/dL. Which of the following is the most likely diagnosis? (A) Bacterial meningitis (B) Dextromethorphan intoxication (C) Herpes simplex encephalitis (D) HIV encephalopathy (E) Reye syndrome (F) Syphilis

*Answer C is correct.* In a patient with symptoms of encephalitis, the presence of bitemporal hyperintensities on MRI suggests herpes simplex encephalitis. Cerebrospinal fluid findings are consistent with this diagnosis. Answer A is incorrect. Bacterial meningitis would not produce these cerebrospinal fluid findings or cause bitemporal hyperintensities to appear on MRI. Answer B is incorrect. Dextromethorphan intoxication causes hallucinations, gait disturbance, and clinical findings of sympathetic stimulation. Neurobehavioral changes may include euphoria, hallucinations, inappropriate laughing, psychosis with dissociative features, agitation, and coma. Physical findings include tachycardia, dilated pupils, diaphoresis, and "zombie-like" ataxic gait. The patient in this scenario does not have findings of sympathetic stimulation. Answer D is incorrect. HIV encephalopathy is also known as AIDS dementia complex (ADC). Nearly all patients with AIDS develop HIV encephalopathy at some time during the course of the disease. All persons with changes in mental status should be questioned about risk factors for HIV exposure; if any are present, serum testing should be performed. HIV encephalopathy is the most common but by no means the only neurologic manifestation of HIV infection. Although a wide variety of infections and neoplastic brain diseases may occur, the dementia syndrome progresses in a fairly predictable fashion. Forgetfulness, poor concentration, and slowing of thought are early symptoms. Apathy and social withdrawal often appear early and become progressively severe. Psychomotor retardation occurs. Memory impairment and disturbances of higher cortical functioning become apparent as the disease progresses. Delusions, hallucinations, and agitation may occur. The terminal state is usually characterized by "quiet confusion." The patient in this scenario has an acute process manifested by headache, confusion, and seizure, not a chronic process of dementia, suggestive of HIV encephalopathy. Answer E is incorrect. Reye syndrome is a rare but serious condition that causes swelling in the liver and brain. Reye's syndrome most often affects children and teenagers recovering from a viral infection and who may also have a metabolic disorder. Signs and symptoms, such as confusion, seizures and loss of consciousness, require emergency treatment. Early diagnosis and treatment of Reye's syndrome can save a child's life. Aspirin has been linked with Reye's syndrome. Though aspirin is approved for use in children older than age 2, children and teenagers recovering from chickenpox or flu-like symptoms should never take aspirin. In Reye's syndrome, a child's blood sugar level typically drops while the levels of ammonia and acidity in his or her blood rise. At the same time, the liver may swell and develop fatty deposits. Swelling may also occur in the brain, which can cause seizures, convulsions or loss of consciousness. The signs and symptoms of Reye's syndrome typically appear about three to five days after a viral infection, such as the flu (influenza) or chickenpox, or an upper respiratory infection, such as a cold. Reye's syndrome is not associated with the cerebrospinal fluid findings or bitemporal changes seen in this patient. Answer F is incorrect. Neurosyphilis is simply the occurrence of neurologic complications due to infection with T pallidum. It may occur during early or late syphilis. The spectrum of neurosyphilis is broad. The most common form of neurosyphilis currently diagnosed is asymptomatic neurosyphilis. Individuals with this form of neurosyphilis come to medical attention because of serological evidence of syphilis in the absence of neurologic sequelae. Examination of the cerebrospinal fluid reveals evidence of neurosyphilis; these patients are at risk for developing symptomatic disease. Among the symptomatic disorders of neurosyphilis, the earliest manifestation is syphilitic meningitis, which typically occurs within the first 12 months of infection and may accompany features of secondary syphilis (maculopapular rash affecting the palms and soles). Headaches, meningismus, cranial nerve palsies (chiefly, in descending order of frequency, VII, VIII, VI, and II), hearing loss, tinnitus, and vertigo may be observed in isolation or combination in upwards of 40% of patients with secondary syphilis. Impaired vision secondary to chorioretinitis, retinitis, optic neuropathy, optic chiasmal, or optic tract disease has also been reported. The symptoms of syphilitic meningitis include headache, photophobia, and a stiff neck. Encephalopathic features resulting from vascular compromise or increased intracranial pressure may be observed. These include confusion, lethargy, seizures, aphasia, and hemiplegia. Intractable seizures may, on rare occasions, be the initial manifestation of neurosyphilis. Acute sensorineural hearing loss and acute optic neuritis may occur in association with syphilitic meningitis or independently. Neurosyphilis is no associated with bitemporal hyperintensities on MRI, as were seen in this patient.

A 75-year-old man presents with problems walking that have developed over the previous 2 years, consisting of slow gait, imbalance (especially on turning), short stride length, and gait initiation failure. He reports urinary frequency, occasional urge incontinence, and some memory loss. On examination, his symptoms are symmetric and much more prominent in the lower half of the body, with relative sparing of hand function, and normal facial expressiveness. He has previously been diagnosed with Parkinson disease; however, therapy with levodopa has not improved his symptoms. These findings are most consistent with which of the following conditions? A. Alzheimer disease B. Frontotemporal dementia C. Lewy body disease D. Normal-pressure hydrocephalus E. Parkinson disease F. Vascular dementia

*Answer D is correct.* Normal-pressure hydrocephalus is associated with dementia, gait instability, and urinary incontinence.

A previously healthy 19-year-old college student comes to student health services 24 hours after the onset of headache, stiff neck, and sensitivity to light. She does not recall any sick contacts. She had chickenpox at the age of 7 years. Her most recent examination 1 year ago included PPD skin testing and showed no abnormalities. She takes a daily multivitamin and an herbal weight-loss preparation. She received all appropriate immunizations during childhood but has not received any since then. She does not smoke, drink alcohol, or use illicit drugs. There is no family history of serious illness. She appears lethargic. Her temperature is 39.1°C (102.4°F), pulse is 112/min, respirations are 20/min, and blood pressure is 100/68 mm Hg. Examination shows diffuse petechiae. Kernig and Brudzinski signs are present. The remainder of the examination shows no abnormalities. A lumbar puncture is performed. Cerebrospinal fluid (CSF) analysis shows numerous segmented neutrophils and a decreased glucose concentration. A Gram stain of the CSF shows gram-negative cocci. Which of the following is the most appropriate pharmacotherapy? (A) Ceftriaxone (B) Clindamycin (C) Erythromycin (D) Metronidazole (E) Vancomycin

Answer A is correct. The presence of fever, headache, stiff neck, petechiae, positive Kernig and Brudzinski signs, and CSF with neutrophils, low glucose, and gram-negative diplococci suggests meningococcal meningitis. A third-generation cephalosporin, such as ceftriaxone, is the treatment of choice.

A 72-year-old woman is brought to the emergency department 2 hours after the sudden onset of visual loss in her right eye. Visual acuity is limited to light perception on the right. Examination of the right eye shows an afferent papillary defect. The anterior structures of both eyes appear normal. Funduscopic findings of the right eye are shown. Which of the following is the most likely diagnosis? (A) Background diabetic retinopathy (B) Central artery occlusion (C) Central vein occlusion (D) Papilledema (E) Proliferative diabetic retinopathy

Answer B is correct. Central retinal artery occlusion Occlusion (usually embolic, but sometimes thrombotic or inflammatory) of the central retinal artery can result in severe vision loss. The main artery supplying the eye is the ophthalmic artery. The part of the ophthalmic artery that enters the eye at the optic nerve is called the central retinal artery. Risk factors for central retinal artery occlusion include atherosclerosis, cardiac disease, and hypercoagulable states. Patients usually complain of the acute painless vision loss. This may have been preceded by transient loss of vision (amaurosis fugax) due to embolization. Occlusion of the central retina artery results in an afferent papillary defect. The affected (ischemic) part of the retina appears white (retinal ganglion cells swell due to ischemia). The foveal center (center of the macula) appears red (called a cherry red spot). This occurs because there are no ganglion cells to swell and obscure the underlying color. Acutely, diagnosis is prompted by the sudden onset of visual acuity loss and the presence of retinal whitening. This image above shows retinal whitening and a "cherry red" spot. Answer A is incorrect. Non-proliferative diabetic retinopathy Non-proliferative diabetic retinopathy, previously called background retinopathy, is the earliest stage of diabetic eye disease. Microscopic changes occur in the blood vessels of the eye in non-proliferative disease; however, the changes typically do not produce symptoms and are not visible to the naked eye. Non-proliferative disease progresses from mild to moderate to severe. Non-proliferative diabetic retinopathy is initially characterized by microaneurysms (microscopic blood-filled bulges in the artery walls) which may burst and leak into the retina. Tiny spots or dots of blood may accumulate in the retina, but they usually do not produce noticeable symptoms in the early stages of the disease. As the disease progresses, hard exudates (accumulations of fluid that has leaked from blood vessels), abnormalities in the growth of microscopic blood vessels in the retina, and bleeding from the veins that feed the retina may occur. While non-proliferative diabetic retinopathy is not itself a sight-threatening condition, it can trigger macular edema or macular ischemia, which can cause rapid vision loss. As the severity of non-proliferative retinopathy increases, the risk of developing sight-threatening proliferative diabetic retinopathy also increases. Answer C is incorrect. Central retinal vein occlusion Central retinal vein occlusion presents with visual loss. The fundus may show retinal hemorrhages, dilated tortuous retinal veins, cotton-wool spots, macular edema, and optic disc edema. Answer D is incorrect. Papilledema Papilledema results from increased intracranial pressure. Signs include venous engorgement, loss of venous pulsation, hemorrhages near the optic disc, blurring of optic margins, elevation of optic disc, and Paton's lines (radial retinal lines cascading from the optic disc.) Answer E is incorrect. Proliferative diabetic retinopathy Proliferative diabetic retinopathy is characterized by neovascularisation - that is, the growth of abnormal new blood vessels in the retina. The vessels are weak and may burst and bleed into the retina or vitreous fluid, causing vision loss.

A 30-year-old woman comes to the physician because of intermittent throbbing headaches, sweating, and pallor over the past 3 months. She has had several blood pressure measurements that fluctuate from 110/80 mm Hg to 160/108 mm Hg. Her pulse is 100/min, and blood pressure now is 138/88 mm Hg. Serum studies show: Na+ 140 mEq/L Cl− 110 mEq/L K+ 4.5 mEq/L HCO3− 26 mEq/L Urea nitrogen 14 mg/dL Creatinine 1 mg/dL Which of the following is the most likely location of the abnormality? (A) Adrenal cortex (B) Adrenal medulla (C) Aorta (D) Renal arterioles (E) Renal glomeruli (F) Thyroid gland

Answer B is correct. Pheochromocytoma, a tumor of the adrenal medulla, causes hypertension, headache, pallor, and sweating. Blood pressure readings can be quite labile. Answer A is incorrect. Primary aldosteronism causes hypokalemia and is not typically associated with pallor and sweating. Answer C is incorrect. Coarctation of the aorta causes blood pressure to be much higher in the upper extremities than in the lower extremities. It is not typically associated with pallor or sweating. Answer D is incorrect. Renal artery stenosis may produce an abdominal bruit and is not typically associated with pallor or sweating. Answer E is incorrect. Chronic kidney disease is the most common cause of secondary hypertension. It is associated with an elevated serum creatinine level and does not typically cause pallor or sweating. Answer F is incorrect. Hyperthyroidism raises blood pressure and causes sweating, but is not associated with pallor.

A 77-year-old man is brought to the physician because of a 12-hour history of word-finding difficulty and weakness and sensory loss of the right arm and leg. He has no history of similar symptoms. He has type 2 diabetes mellitus, hypertension, and atrial fibrillation. Current medications include metformin, lisinopril, and aspirin. He is alert. His pulse is 80/min and irregular, respirations are 16/min, and blood pressure is 170/90 mm Hg. He follows commands but has nonfluent aphasia. There is moderate weakness and decreased sensation of the right upper and lower extremities. Deep tendon reflexes are 2+ bilaterally. Babinski sign is present on the right. His serum glucose concentration is 162 mg/dL. Which of the following is the most appropriate next step in diagnosis? (A) Carotid duplex ultrasonography (B) CT scan of the head (C) EEG (D) Lumbar puncture (E) Cerebral angiography

Answer B is correct. The patient has findings consistent with stroke in the distribution of the left middle cerebral artery. CT scan, the first test recommended in the evaluation of stroke, can distinguish ischemic stroke from hemorrhagic stroke. It can also identify other abnormalities, such as tumor. Answer A is incorrect. Carotid duplex ultrasonography is useful in the work-up of stroke, but should not precede CT evaluation. Answer C is incorrect. Electroencephalography is used to evaluate patients with seizure. Answer D is incorrect. Lumbar puncture is used to evaluate patients with suspected meningitis. Answer E is incorrect. Cerebral angiography is used to evaluate patients with suspected cerebral vasculitis or cerebral aneurysm.

A 20-year-old woman with no significant past medical history presents with lower back pain and bilateral foot and hand tingling. Her symptoms rapidly progress over 4 days to include lower extremity weakness to the point that she is unable to mobilize her lower extremities. She reports coryzal symptoms 2 weeks ago. On examination, she has 0/5 power in her lower extremity with areflexia, but despite the paresthesias she does not have sensory deficits. Her aminotransferases are elevated, and CSF examination reveals mildly elevated protein with no cells and normal glucose. Which of the following is the most likely diagnosis? A. Amyotrophic lateral sclerosis B. Botulism C. Guillain-Barré syndrome D. Multiple sclerosis E. Myasthenia gravis

Answer C is correct. Guillain-Barré syndrome. Guillain-Barré syndrome is an acute inflammatory demyelinating polyneuropathy (AIDP), an autoimmune disorder affecting the peripehral nervous system, usually triggered by an acute infectious process. Typically, the patient experiences ascending paralysis, in which leg weakness spreads to the upper limbs and face. There is complete loss of deep tendon reflexes. With prompt treatment, the majority of patients recover. Death may result, however, from respiratory or autonomic nervous system dysfunction. Amyotrophic lateral sclerosis (ALS). ALS is a disease that affects upper and lower motor neurons. Most patients present with spasticity and hyperreflexia (upper motor neuron signs) and progressive muscle weakness and atrophy (lower motor neuron signs). Cognitive function, bowel and bladder function, and eye movements are usually preserved. The disease is relentless and progressive: Affected individuals lose control of voluntary movements, and respiratory paralysis ensues. Sensory and autonomic nerves are usually spared. ALS may be familial or acquired. The two forms are clinically and pathologically indistinguishable. Botulism. Botulism is a rare, toxin-mediated, paralytic disease. The toxin is produced by the bacterium Clostridium botulinum. The disease may be acquired by bacterial colonization of the digestive tract, by direct ingestion of toxin, or by wound contamination. Paralysis typically starts with the cranial nerves and spreads to the limbs. The patient may present with double vision, drooping of the eyelids, loss of facial expression, or difficulty with swallowing or talking. The weakness then spreads to the arms (starting in the shoulders and proceeding to the forearms) and legs (starting with the thighs and proceeding to the feet). The autonomic nervous sytem may be affected, causing dry mouth and throat, postural hypotension, and constipation. Nausea and vomiting may occur, and, in severe forms, respiratory paralysis ensues. Multiple sclerosis. Multiple sclerosis is an inflammatory disease in which the myelin sheaths around the axons of the brain and spinal cord are damaged, leading to demyelination and scarring. (Myelin is a substance that provides "electrical insulation." It forms a layer, the myelin sheath, which is usually around only the axon of a neuron. Schwann cells supply the myelin for peripheral neurons, whereas oligodendrocytes myelinate the axons of the central nervous system.) Multiple sclerosis usually begins in young adults. Women are more commonly affected than men. Patients can have almost any neurological finding, including fatigue, visual changes, altered sensation, pain, muscle weakness, difficulty with movement or balance, problems with speech or swallowing, and bowel or bladder dysfunction. Cognitive and mood changes may occur. Uhthoff's phenomenon (exacerbation of symptoms with exposure to heat) and Lhermitte's sign (an electrical sensation running down the back when bending the neck) are characteristic but not specific for multiple sclerosis. Symptoms may progress gradually or alternate between relapse and remission. Myasthenia gravis. Myasthenia gravis is an autoimmune neuromuscular disease that causes fluctuating muscle weakness and fatigability. Weakness is caused by circulating antibodies that block acetylcholine receptors at the post-synaptic neuromuscular junction. The hallmark of myasthenia gravis is fatigability: Muscles become weaker with activity and stronger with rest. Especially susceptible are the muscles that control eye and eyelid movements, facial expression, chewing, talking, and swallowing. Presenting symptoms include ptosis, diplopia, dysarthria, dysphagia, and change in facial expression. Neck and limb movements may be affected, gait may be unsteady, and breathing may be impaired.

A 3-year-old girl is brought to the physician because of fever and left ear pain for 3 days. She has been treated with amoxicillin for the past 5 days for left otitis media. Her temperature is 38.5°C (101.3°F), pulse is 100/min, respirations are 20/min, and blood pressure is 80/60 mm Hg. Examination shows the left ear displaced forward and laterally from the head. There is edema and tenderness behind the left ear. Otoscopic examination shows a red, dull, left tympanic membrane that does not move. Which of the following is the most likely diagnosis? (A) Acoustic neuroma (B) Labyrinthitis (C) Lateral sinus thrombosis (D) Mastoiditis (E) Rhabdomyosarcoma

Answer D is correct. Fever and ear pain associated with otitis media and displacement (forward and lateral) of the ear suggest a diagnosis of mastoiditis. Answer A is incorrect. An acoustic neuroma (or more precisely, vestibular schwannoma) is a benign tumor that arises from the Schwann cells of cranial nerve VIII. Acoustic neuromas account for about 10% of all intracranial tumors. They are most commonly diagnosed in middle age. They are slightly more common in women than men. They are usually sporadic but may be associated with neurofibromatosis 1 or 2 (NF-1, NF-2). Most patients with NF-2 will develop bilateral acoustic neuromas. Acoustic neuromas in NF-1 are much less common. The primary symptoms of vestibular schwannoma are asymmetric hearing loss (sensorineural) and tinnitus. The hearing loss is usually gradual in onset and progressive but can occur suddenly. Disequilibrium is not usually the chief complaint on presentation, but patients often admit to mild unsteadiness. Larger tumors can cause dysesthesia around the ear or facial weakness, or both. If the neuroma is diagnosed late, patients can manifest cerebellar symptoms and symptoms of mass effect and obstructing hydrocephalus. After a complete neuro-otologic examination and audiologic evaluation, an MRI scan of the brain with fine cuts through the internal auditory canal with gadolinium contrast is necessary for diagnosis. Treatment options include observation, surgery, or stereotactic radiotherapy. Most vestibular schwannomas require treatment to prevent cerebral complications from future growth. Answer B is incorrect. Labyrinthitis causes sudden and severe vertigo, tinnitus, and hearing loss. The hearing loss is sensorineural, is often severe, and can be permanent. Labyrinthitis is caused by inflammation within the inner ear. The cause is most often a viral infection but can be bacterial. Bacterial labyrinthitis usually results from extension of a bacterial otitis media into the inner ear. A noninfectious serous labyrinthitis can also occur after an episode of acute otitis media. Other, less common causes include treponemal infections (syphilis) and rickettsial infection (Lyme disease). Antibiotics are recommended if a bacterial cause is suspected. As with acute otitis media, bacterial labyrinthitis can, in rare cases, lead to meningitis. Few other conditions cause the constellation of hearing loss, tinnitus, and vertigo, but cerebrovascular ischemia, meningitis, brain abscess, and encephalitis should all be considered. Although the vertigo should resolve over days to weeks, hearing loss and tinnitus can persist. Drugs known to be ototoxic can cause acute onset of hearing loss and disequilibrium, although this is not true labyrinthitis. These drugs include salicylates, aminoglycosides, loop diuretics, and various chemotherapeutic agents. This cause should be considered in patients who complain of hearing loss or dizziness while taking these medications. Answer C is incorrect. Septic thrombosis of the lateral sinus results from acute or chronic infections of the middle ear. Symptoms consist of ear pain and fever followed by headache, nausea, vomiting, loss of hearing, and vertigo, usually evolving over a period of several weeks. Symptoms or signs suggestive of otitis media, including mastoid swelling, may be seen. Sixth cranial nerve palsies can occur, but other focal neurologic signs are rare. In some patients with nonseptic lateral sinus thrombosis, headache may be the only symptom. Papilledema occurs in 50% of cases, and elevated CSF pressure is present in most. Answer E is incorrect. In rhabdomyosarcoma, cancer cells arise from skeletal muscle progenitors. Most tumors of this type occur in the head, neck, or genitourinary tract. Rhabdomyosarcoma is a relatively rare form of cancer. It is most common in children ages one to five.

A 27-year-old man comes to the physician because of persistent headaches since a motor vehicle collision 2 weeks ago. In the collision, he struck his head on the windshield but did not lose consciousness. The headaches are generalized with a constant pressure-like pain. He also has had memory loss and difficulty sleeping. Neurologic examination and an MRI of the brain show no abnormalities. Which of the following is the most likely diagnosis? (A) Increased intracranial pressure (B) Migraine (C) Occipital neuralgia (D) Post-traumatic headache (E) Subarachnoid hemorrhage (F) Subdural hematoma (G) Temporomandibular joint syndrome (H) Tension-type headache

Answer D is correct. Post-traumatic headache is associated with irritability, concentration impairment, insomnia, memory disturbance, and light-headedness. Anxiety and depression are present to variable degrees. Neurological examination and MRI of the brain would be normal.

A 47-year-old man comes to the physician 12 hours after the sudden onset of a severe occipital headache and stiff neck. He has not had any other symptoms and has no history of severe headache. He has hypertension and gastroesophageal reflux disease. Current medications include hydrochlorothiazide and ranitidine. He is oriented to person, place, and time. His temperature is 36.7°C (98.1°F), pulse is 100/min, and blood pressure is 160/90 mm Hg. Range of motion of the neck is decreased due to pain. Neurologic examination shows no focal findings. Which of the following is the most likely diagnosis? (A) Cluster headache (B) Meningitis (C) Migraine (D) Subarachnoid hemorrhage (E) Tension-type headache

Answer D is correct. Sudden onset of a severe occipital headache and neck stiffness, particularly in an individual with no history of severe headache, is worrisome for subarachnoid hemorrhage. The absence of focal findings on neurological exam is not surprising. This patient should undergo CT scanning of brain. If the CT scan is normal, lumbar puncture should be undertaken and the cerebrospinal fluid should be centrifuged to detect xanthochromia. Answer A is incorrect. The pain in cluster headache is of extreme intensity, is unilateral, and is associated with congestion of the nasal mucosa and injection of the conjunctiva on the side of the pain. Increased sweating of the ipsilateral side of the forehead and face may occur. There may be associated ocular signs of Horner syndrome: miosis, ptosis, and the additional feature of eyelid edema. The pain is usually steady, nonthrobbing, and invariably localized retro-orbitally on one side of the head; it may occasionally spread to the ipsilateral side of the face or neck. Attacks often awaken patients, usually 2 to 3 hours after the onset of sleep ("alarm-clock headache"). The duration of headache is usually around 1 hour, although it may recur several times in a day, recurring paroxysmally (in clusters) for several weeks. Answer B is incorrect. Patients with bacterial meningitis may exhibit fever, headache, lethargy, confusion, irritability, and stiff neck. One of three principal modes of onset can occur. (1) Approximately 25% of cases begin abruptly with fulminant illness; mortality is very high in this setting. (2) More often, meningeal symptoms progress over 1 to 7 days. (3) Meningitis may superimpose itself on 1 to 3 weeks of an upper respiratory-type illness; diagnosis is most difficult in this group. Occasionally, no more than a single additional neurologic symptom or sign hints at disease more serious than a routine upper respiratory tract infection. Stiff neck is absent in roughly one half of all patients with meningitis, notably in the very young, the old, and the comatose. A petechial or purpuric rash is found in one half of patients with meningococcemia; although not pathognomonic, palpable purpura is very suggestive of N. meningitidis infection. Approximately 20% of patients with acute bacterial meningitis have seizures, and a similar fraction has focal neurologic findings. The absence of fever in this patient goes against a diagnosis of meningitis. Answer C is incorrect. The two most common types of migraine are migraine without aura and migraine with aura; migraine without aura accounts for 80% of patients. Migraine auras are focal neurologic symptoms that precede, accompany, or, rarely, follow an attack. The aura usually develops over 5 to 20 minutes, lasts less than 60 minutes, and can involve visual, sensorimotor, language or brainstem disturbances. The most common aura is typified by positive visual phenomena (such as scintillating scotomata) that often precede the headache; they resemble the effect of being too close to a photographer with a flash camera (phosphenes). The pain of migraine is often pulsating, unilateral, and frontotemporal in distribution and often accompanied by anorexia, nausea, and, occasionally, vomiting. In characteristic attacks, patients are markedly intolerant of light (photophobia) and seek rest in a dark room. There may also be intolerance to sound (phonophobia) and occasionally to odors (osmophobia). The diagnosis of migraine requires the presence of at least one of these features, particularly in the absence of gastrointestinal symptoms. The presence of these symptoms results in a syndrome that is invariably disabling for the patient, to the extent that for the duration of the attack he or she is unable to function normally. In children, migraine is often associated with episodic abdominal pain, motion sickness, and sleep disturbances. Onset of typical migraine late in life (older than age 50) is rare, although recurrence of migraine that had been in remission is not uncommon. Recurrent migraine headache associated with transient hemiparesis or hemiplegia occurs rarely as a clearly genetically determined (Mendelian) disease (familial hemiplegic migraine). In this patient, the location of the headache, presence of neck stiffness, and absence of associated symptoms argue against the diagnosis of migraine. Also, it would be unusual for a migraine headache to appear for the first time in a 47-year-old man. Answer E is incorrect. In contrast to migraine, pain of tension-type headache is usually not throbbing but rather steady and often described as a "pressure feeling" or a "viselike" sensation. It is usually not unilateral and may be frontal, occipital, or generalized. There is frequently pain in the neck area, unlike in migraine. Pain commonly lasts for long periods of time (e.g., days) and does not rapidly appear and disappear in attacks. There is no "aura." Photophobia and phonophobia are usually absent. Although tension-type headache may be related by the patient to occur or be exacerbated at times of particular emotional stress, the pathophysiology may relate to sustained craniocervical muscle contraction; hence, a more appropriate term for this syndrome is muscle-contraction headache. A careful evaluation should be made of the patient's psychosocial milieu and the presence of anxiety or depression. The tricyclic antidepressant drugs in low doses have proven the most useful for prevention of tension-type headache; although the best documented is amitriptyline, newer agents with fewer side effects may be equally effective. Nonpharmacologic therapies such as relaxation therapy, massage, physiotherapy, or acupuncture may be useful in refractory cases. The presence of sudden-onset, severe headache with neck stiffness in this patient is not suggestive of tension-type headache.

A 9-month-old boy is brought to the physician because of discharge from the left ear for 1 day. He has had frequent infections since the age of 4 months. He had Streptococcus pneumoniae bacteremia at 4 months of age, Haemophilus influenzae meningitis at 5½ months of age, and S. pneumoniae pneumonia at 7 months of age. He also has had two episodes of otitis media during this period. He is an only child, and there is no family history of frequent infections. His immunizations are up-to-date. He is at the 20th percentile for length and 3rd percentile for weight. He is not in acute distress. Examination shows no abnormalities other than a purulent drainage from the left ear canal. Which of the following is the most likely diagnosis? A. Chronic granulomatous disease of childhood B. Severe combined immunodeficiency C. Thymic-parathyroid dysplasia (DiGeorge syndrome) D. Transient hypogammaglobulinemia of infancy E. X-linked agammaglobulinemia

Answer E is correct. Recurrent infections with encapsulated bacteria (Streptococcus pneumoniae and Haemophilus influenzae) despite adequate immunization suggest a defect in B-cell/immunoglobulin function, as seen in X-linked agammaglobulinemia. Answer A is incorrect. Patients with chronic granulomatous disease are predisposed to disease by catalase-producing organisms such as staphylococci, Serratia, Nocardia, and Aspergillus. Answer B is incorrect. SCID patients are usually affected by severe bacterial, viral, or fungal infections early in life and often present with interstitial lung disease, chronic diarrhea, and failure to thrive. Ear infections, recurrent Pneumocystis jirovecii pneumonia, and profuse oral candidiasis commonly occur. These babies, if untreated, usually die within 1 year due to severe, recurrent infections unless they have undergone successful hematopoietic stem cell transplantation. Answer C is incorrect. Children with DiGeorge syndrome suffer from recurrent viral and fungal infections within the first year of life. Answer D is incorrect. Infants with transient hypogammaglobulinemia of infancy (THI) typically begin to experience increasingly frequent and recurrent otitis media, sinusitis, and bronchial infections. Life-threatening infections with polysaccharide-encapsulated bacteria are unusual. Because antigen-specific antibody responses are largely intact, this likely accounts for the lack of serious bacterial infections observed in THI. In children older than 3 years, the frequency of infections typically diminishes, even if serum immunoglobulin levels have not yet normalized. T cell immunity is intact, and infections with opportunistic microorganisms do not usually occur.

A 32-year-old woman comes to the physician because of an 8-month history of moderately severe, bilateral, diffuse headaches that last "all day, every day." They are not responsive to over-the-counter medications. She has not had nausea, vomiting, or aura. She appears mildly depressed. Neurologic examination shows no abnormalities. Which of the following is the most likely diagnosis? A. Increased intracranial pressure B. Migraine C. Occipital neuralgia D. Post-traumatic headache E. Subarachnoid hemorrhage F. Subdural hematoma G. Temporomandibular joint syndrome H. Tension-type headache

Answer H is correct. Steady diffuse headaches in the absence of nausea, vomiting, aura, and neurological findings are likely to be tension-type headaches. Answer A is incorrect. Headaches due to increased intracranial pressure are usually mild and worse in the morning or with exertion. Visual disturbances may occur and papilledema may be present. Answer B is incorrect. The pain of migraine is often pulsating, unilateral, and frontotemporal in distribution and often accompanied by anorexia, nausea, and, occasionally, vomiting. In characteristic attacks, patients are markedly intolerant of light (photophobia) and seek rest in a dark room. Some migraines are accompanied by aura. Answer C is incorrect. Occipital neuralgia is characterized by a sharp, lancinating pain lasting a few seconds and occurring repetitively in the occipital region. Symptoms may be provoked by neck extension. Answer D is incorrect. Post-traumatic headache occurs after head injury and is associated with irritability, concentration impairment, insomnia, memory disturbance, and light-headedness. Anxiety and depression are present to variable degrees. Answer E is incorrect. Subarachnoid headache is usually extremely severe and often described by the patient as "the worst headache of my life." Nuchal rigidity, third nerve palsy (usually involving the pupil), and retinal, preretinal, or subconjunctival hemorrhages may be found. Answer F is incorrect. Subdural hematoma occurs after head injury and is commonly associated with abnormalities on neurological exam. Answer G is incorrect. Temporomandibular joint (TMJ) syndrome is associated with pain and tenderness over the TMJ and muscles of mastication, as well as decreased range of motion of the TMJ.

A 67-year-old man is brought to the emergency department because of headache and decreased level of consciousness over the past hour. He has a 20-year history of poorly controlled hypertension. He is unresponsive to verbal stimuli. With painful stimulation, he moves the left extremities semipurposely but not the right extremities. The left pupil is larger than the right and reacts sluggishly to light. Babinski sign is present on the right. A CT scan of the head shows a large hyperintense mass in the left basal ganglia with compression of the left lateral ventricle and shift of the midline structures. Which of the following is the most likely diagnosis? (A) Acute cerebral infarction (B) Arteriovenous malformation (C) Astrocytoma (D) Bacterial abscess (E) Carotid cavernous fistula (F) Epidural abscess (G) Epidural hematoma (H) Fungal abscess (I) Glioblastoma multiforme (J) Intracerebral hemorrhage (K) Medulloblastoma (L) Meningioma (M) Metastatic carcinoma (N) Mycobacterium avium-intracellulare granuloma (O) Sturge-Weber syndrome (P) Subarachnoid hemorrhage (Q) Subdural hematoma

Answer J is correct. Headache and decreased level of consciousness in a 67-year-old man with hypertension and a hyperintense mass on CT indicates intracerebral hemorrhage. In this vignette, there is evidence of left uncal herniation. (The uncus squeezes the third cranial nerve, affecting the parasympathetic input to the eye, which causes the pupil to dilate and become less reactive to light.)