1.
A 24-year-old woman is evaluated for a new-onset severe headache. The headache began acutely 3 days ago and is constant and localized to the right temporal area of the head. She has taken ibuprofen and acetaminophen without relief. She also reports swelling along the right side of her jaw that began about 2 weeks ago. On physical examination, temperature is 37.1°C (98.8°F); the remaining vital signs are normal. Her face is swollen and erythematous along the right mandible without evidence of drainage. A contrast-enhanced CT scan of the head and face shows a soft-tissue mass surrounding the right mandible. There is a 3-cm ring-enhancing lesion in the right temporal lobe of the brain. The patient undergoes CT-guided stereotactic aspiration of the lesion.
Which of the following organisms would you expect to be isolated from the pus submitted to the laboratory for culture?
Correct Answer
A. Bacteroides fragilis and viridans group streptococci
Explanation
The patient's presentation is consistent with a deep space infection, specifically a brain abscess, which is supported by the presence of a ring-enhancing lesion on CT scan. The swelling along the right side of the jaw suggests an odontogenic source of infection. Bacteroides fragilis is a common anaerobic organism found in the oral cavity and is a common cause of brain abscesses. Viridans group streptococci are also commonly found in the oral cavity and can cause deep space infections. Therefore, it is likely that these organisms would be isolated from the pus submitted for culture.
2.
A 27 years old woman has sustained a severe traumatic brain injury. Wallerian degeneration is now occuring in her brain. Wallerian degeneration is the evolution of which of the following?
Correct Answer
C. Diffuse axonal injury
Explanation
Wallerian degeneration is the process of degeneration and disintegration of the axons of nerve cells that occurs when the nerve fiber is severed or damaged. In the case of a severe traumatic brain injury, diffuse axonal injury is a common occurrence where there is widespread damage to the axons throughout the brain. This is likely the reason for the occurrence of Wallerian degeneration in this woman's brain.
3.
A 34-year-old man was admitted to the hospital for reduction of a dislocated shoulder. Sedation with diazepam was supplemented with administration of 30% concentration of nitrous oxide. Which of the following effects most likely occurred after nitrous oxide administration?
Correct Answer
B. Analgesia was very pronounced
Explanation
After administration of nitrous oxide, the most likely effect that occurred is analgesia being very pronounced. Nitrous oxide is commonly used as an analgesic in medical procedures due to its ability to provide pain relief. It does not cause unconsciousness or significantly decrease blood pressure, and while it may cause some muscle relaxation, it is not described as "excellent." Nitrous oxide can also cause respiratory depression, but this effect is not mentioned in the question stem. Therefore, the most likely effect in this case is pronounced analgesia.
4.
A child, female, age 7, is experiencing a seizure that involves the muscles of her entire body. At the beginning of the seizure, the muscles become intensely contracted. Then they go through a series of contraction-relaxation. The child is apparently not aware of her environment. Describe the seizure:
Correct Answer
C. Generalized convulsive
Explanation
The given description of the seizure indicates that the child is experiencing a generalized convulsive seizure. This type of seizure involves the muscles of the entire body and is characterized by intense muscle contractions followed by a series of contraction-relaxation cycles. The child's lack of awareness of her environment further supports the diagnosis of a generalized seizure, as opposed to a partial seizure which typically allows for some level of awareness.
5.
A 4-year old girl suffers from a congenital disease which involves frequent constipation and slow growth. From your medical studies you know that this congenital condition is a result of a blockage of the large intestine due to improper muscle movement in the bowel. Which specific part of the nervous system is absent in this disease?
Correct Answer
B. Enteric nervous system
Explanation
The enteric nervous system is responsible for controlling the movement and function of the gastrointestinal tract, including the muscles in the bowel. In this case, the absence of the enteric nervous system is causing improper muscle movement in the bowel, leading to constipation and slow growth.
6.
A 2-year-old child is brought to the emergency department following a seizure. His mother reports that he had a cold with cough, congestion, and fever for several days prior to this ED visit. He has been irritable, would not eat, and has been excessively sleepy. His parents are against immunizations based on religious grounds. On physical examination, he is febrile, tachycardic, and appears very ill. He grimaces when you try to bend his neck. No skin rash is noted. A CT scan of his head is normal. A lumbar puncture is performed. CSF analysis reveals the following:
CSF Parameter Results Reference Range
Opening pressure 300 mm H2O 100-200
Total WBC count 1,250 cells/mm3 0-5
Differential count 95% PMNs ---
Glucose 35 mg/dL 50-80
Protein 100 mg/dL 20-45
Results of the Gram stain of the CSF is shown below:
Which of the following is the most appropriate procedure to definitively identify the causative agent?
Correct Answer
A. Culture the CSF on blood agar and chocolate agar media
Explanation
The most appropriate procedure to definitively identify the causative agent is to culture the CSF on blood agar and chocolate agar media. This allows for the growth and isolation of the organism present in the CSF. By observing the characteristics of the organism and performing further tests, such as a catalase test or a coagulase test, the specific causative agent can be identified. The other options, such as performing a latex agglutination test or culturing the CSF on mannitol salt agar medium, would not provide a definitive identification of the causative agent.
7.
If a 40-year-old man, diagnosed with an acute right subdural hematoma, suddenly develops right ptosis with a dilated pupil non-reactive to light, the most likely cause of these findings is:
Correct Answer
C. Transtentorial hypoccampal herniation
Explanation
The most likely cause of a 40-year-old man with an acute right subdural hematoma suddenly developing right ptosis with a dilated pupil non-reactive to light is transtentorial hippocampal herniation. This condition occurs when there is increased pressure in the brain, causing the medial temporal lobe to herniate through the tentorial incisura. This can lead to compression of the oculomotor nerve, resulting in ptosis and dilation of the pupil. The other options, such as acute hydrocephalus, occipital lobe infarct, and laceration of pedunculi, are less likely to cause these specific findings.
8.
The following list of primary malignancies accounts for the majority of metastatic brain tumors; choose the best answer.
Correct Answer
D. Lung, breast, melanoma
Explanation
Metastatic brain tumors occur when cancer cells from a primary tumor in another part of the body spread to the brain. The answer "lung, breast, melanoma" is the best choice because these three types of cancer are known to frequently metastasize to the brain. Lung cancer is the most common cause of brain metastases, followed by breast cancer and melanoma. Therefore, these primary malignancies account for the majority of metastatic brain tumors.
9.
A 21-year-old female underwent a craniectomy because of a tumor mass located in the right fronto-parietal region. The pathologist examines the tumor in a hematoxilin-eosin-stained section and would like to identify the cells of astrocytic origin. Which IHQ stain he would most likely order?
Correct Answer
E. GFAP (Glial fast acidic protein)
Explanation
The pathologist would most likely order the GFAP (Glial fast acidic protein) stain to identify the cells of astrocytic origin. GFAP is a specific marker for astrocytes, which are a type of glial cell found in the central nervous system. By staining for GFAP, the pathologist can distinguish astrocytes from other cell types and confirm the presence of astrocytic cells in the tumor. This stain is commonly used in immunohistochemistry to identify specific cell types based on the expression of certain proteins.
10.
A 31-year-old man was brought to the hospital emergency room after a he was hit by a car. He was conscious on admission. CT images of the head demonstrated cerebral cytotoxic edema with no evidence of parenchyma or extra-axial hemorrhage. He became tachypneic and hypoxic. The pathologic alteration in this patient’s brain is most likely related to one of the following mechanisms:
Correct Answer
A. It is associated with dilutional hyponatremia
Explanation
The patient in this scenario experienced cerebral cytotoxic edema, which is characterized by swelling of brain cells due to an influx of water. This condition is most commonly associated with dilutional hyponatremia, which occurs when the concentration of sodium in the blood is diluted due to excessive fluid intake or retention. This dilution of sodium leads to an osmotic imbalance, causing water to enter the brain cells and leading to cytotoxic edema. The other options, such as brain herniation, expanding mass lesion, breakdown of the blood-brain barrier, or affecting mainly the gray matter, do not align with the given information and are not the most likely mechanism in this case.
11.
A 20 year old woman attends to the hospital with rapidly ascending weakness in her distal extremities, to involving proximal muscles. On physical examination there is absence of deep tendon reflexes and a spinal tap reveals the CSF protein to be increased, glucose is half the amount of plasma and scant cells are reported. She had recovered from a viral respiratory tract infection two weeks before. A biopsy study of a peripheral nerve had inflammation and demyelination. The diagnosis in this patient is:
Correct Answer
A. Guillain-Barre syndrome
Explanation
The given patient presents with rapidly ascending weakness in her extremities, absence of deep tendon reflexes, increased CSF protein, and inflammation and demyelination in a peripheral nerve biopsy. These findings are consistent with Guillain-Barre syndrome, an autoimmune disorder characterized by inflammation and demyelination of peripheral nerves. The history of a recent viral respiratory tract infection further supports this diagnosis, as Guillain-Barre syndrome is often preceded by an infection. Myasthenia gravis is characterized by muscle weakness and fatigue, but it does not typically present with absent deep tendon reflexes or CSF abnormalities. Syringomyelia, Charcot-Marie-Tooth disease, and metabolic neuropathy do not fit with the clinical findings described.
12.
Your 42-year-old female patient presents with a history of type II diabetes. She complains of dysphoric mood, difficulty concentrating, sleep disturbance, appetite disturbance, back pain, headache and fatigue for the past three weeks. What is the most likely type of mood disorder exhibited by this patient?
Correct Answer
B. Major depressive disorder
Explanation
Based on the patient's symptoms of dysphoric mood, difficulty concentrating, sleep disturbance, appetite disturbance, back pain, headache, and fatigue, it is most likely that she is experiencing major depressive disorder. These symptoms are consistent with the criteria for major depressive disorder, which include a depressed mood, loss of interest or pleasure in activities, changes in appetite or weight, sleep disturbances, fatigue or loss of energy, difficulty concentrating, and physical symptoms such as back pain and headaches. The patient's history of type II diabetes may contribute to the development of the mood disorder, but it is not the primary cause.
13.
You enter a room at your family practice office to find an adult male patient placing several medical supplies into his backpack. When you ask what he is doing, he explains that he needs the supplies for his wife, who is very ill, and that the couple is unable to afford these materials on their own. When you consult his chart, you find that the patient’s marital status is listed as “single,” and further investigation reveals that this individual was actually using an alias, having apparently stolen both a driver’s license and insurance card from another patient. This individual’s pattern of behavior appears most consistent with which of the following personality disorders?
Correct Answer
C. Antisocial
Explanation
The individual's behavior of stealing another patient's identity and lying about his marital status suggests a disregard for societal norms and a lack of empathy for others. These traits are consistent with Antisocial Personality Disorder, which is characterized by a pattern of deceit, manipulation, and disregard for the rights of others.
14.
A six year old child is brought to the physician by her anxious parents who complain that she is very restless during the day and her teacher complains that she is disruptive in class at school and interferes with the other children. Her hyperactivity has been for the past two weeks and occurs mostly at school but also at home in the evenings which her parents felt was because of her tiredness after a day at school. What condition would you want to evaluate this child for, which after treatment, would result in a resolution of her problem without resorting to the use of stimulant medication or any form of psychotherapy.
Correct Answer
B. Sleep apnea
Explanation
The correct answer is sleep apnea. Sleep apnea is a condition characterized by pauses in breathing or shallow breathing during sleep, leading to poor sleep quality and excessive daytime sleepiness. In children, sleep apnea can manifest as hyperactivity and disruptive behavior during the day. Treating sleep apnea can improve sleep quality and resolve the behavioral problems without the need for stimulant medication or psychotherapy.
15.
Mr. Davies is 60 years old. He is a successful businessman and likes to have a drink or two with his associates in the evening. One evening he came home, went to sleep and woke at three a.m. with the worst unilateral headache he’d had to date. His nose was stuffy and eyelid drooping on that side. His face was flushed. He had had a similar headache, but not as severe, 2 days before and also the previous week. In the past these headaches had only lasted a ½ hour, so Mr. Davies felt it wasn’t worth calling the doctor. About every 4 or 5 months Mr. Davies gets a week or so of these bad headaches and then they disappear until the next time. Mr. Davies has a classical case of:
Correct Answer
C. Cluster headaches
Explanation
Mr. Davies is experiencing severe unilateral headaches that last for a week or so and then disappear until the next time. These headaches are accompanied by symptoms such as a stuffy nose, drooping eyelid, and flushed face. These symptoms are characteristic of cluster headaches, which are recurring headaches that occur in clusters or cycles. This is the most likely diagnosis based on the symptoms described.
16.
A 23-year-old female has been doing military maneuvers in the desert all day. She returns to base and then is required to attend a parade which involves standing at attention in the sun for half an hour. After a quarter of an hour she suddenly collapses and passes out. She recovers quickly and, apart from feeling a little shaky, is behaving normally. She has most likely suffered from:
Correct Answer
D. Vascular syncope
Explanation
The 23-year-old female likely suffered from vascular syncope. Vascular syncope refers to a temporary loss of consciousness due to a sudden drop in blood pressure and reduced blood flow to the brain. The combination of physical exertion in the desert, standing in the sun for an extended period, and possibly dehydration likely contributed to her collapse. The fact that she recovered quickly and is behaving normally suggests that it was a temporary episode rather than a more severe condition like heat stroke.
17.
A 68-year-old male presents with progressive memory difficulties over 3 years, and is now unable to dress properly without his wife laying out his clothes. A diagnosis is made clinically, but for a definitive diagnosis the most characteristic pathological feature/s would be:
Correct Answer
E. Plaques and tangles
Explanation
Plaques and tangles are the most characteristic pathological features of Alzheimer's disease, which is associated with progressive memory difficulties and cognitive decline. These plaques are made up of beta-amyloid protein and tangles are formed by twisted tau protein fibers. The presence of plaques and tangles in the brain is a definitive diagnostic feature of Alzheimer's disease. The other options, such as abnormal Tau protein and abnormal APOE4, are also associated with Alzheimer's disease but are not as specific or characteristic as plaques and tangles. Frontal atrophy and cerebellar stroke are unrelated to the pathological features of Alzheimer's disease.
18.
A 56-year-old right-handed white male presents with a sudden onset of weakness; right upper more than lower extremity. His speech is non-fluent, with poor repetition and word-finding difficulty. There is a past history of uncontrolled hypertension and diabetes. The clinical / pathophysiological correlation most fitting with this case is:
Correct Answer
B. Middle cerebral artery distribution stroke with an anterior (Broca’s type) apHasia
Explanation
The patient's symptoms of weakness in the right upper extremity, non-fluent speech, poor repetition, and word-finding difficulty are indicative of a stroke affecting the middle cerebral artery distribution. The fact that the patient has an anterior (Broca's type) aphasia further supports this diagnosis. Additionally, the patient's history of uncontrolled hypertension and diabetes increases the likelihood of a stroke. The other options, such as anterior cerebral artery distribution stroke, hemorrhagic stroke, lacunar stroke, and border-zone stroke, do not align with the patient's symptoms and risk factors.
19.
A 31-year-old farm worker is brought to the emergency department obtunded with slow regular respirations. There is no visible sign or report of head trauma. His pupils are midposition and 1-2mm with little or no reaction to light. Which of the following conditions should be considered?
Correct Answer
A. Uncal herniation
Explanation
The presentation of an obtunded patient with midposition and non-reactive pupils suggests uncal herniation. Uncal herniation occurs when the uncus, a part of the temporal lobe, herniates through the tentorium cerebelli, causing compression on the oculomotor nerve. This compression leads to midposition pupils and impaired pupillary light reflex. The absence of head trauma and the presence of slow regular respirations also support the diagnosis of uncal herniation. Bilateral Horner's Syndrome, pontine hemorrhage, opiate overdose, and organophosphate poisoning may present with altered mental status, but they do not typically cause midposition pupils.
20.
An 18 year-old women presents to the University’s clinic with a behavioral problem. She must get up at 5 am in the morning to get to her first class in time. However, the time needed is expanding and she is now missing her class. She must go through a ritual of dressing, packing her books and going through doors and down steps that is taking more and more time. She has always had to be meticulous to get things done right, but she is now facing the fact that she cannot control it. Besides CBT what is the best pharmacotherapy a physician might prescribe for this condition?
Correct Answer
E. Sertraline
Explanation
The given scenario describes symptoms of obsessive-compulsive disorder (OCD), characterized by repetitive and time-consuming rituals. Sertraline is a selective serotonin reuptake inhibitor (SSRI) commonly used to treat OCD, as it helps to increase serotonin levels in the brain, which can reduce obsessive thoughts and compulsive behaviors. Alprazolam is a benzodiazepine used for anxiety disorders, not specifically for OCD. Amphetamine is a stimulant and not indicated for OCD. Clozapine is an antipsychotic used for schizophrenia, not OCD. Imipramine is a tricyclic antidepressant that may be used for OCD but SSRIs like sertraline are generally preferred.
21.
A 32-year old man presents to his family physician with complaints about headaches. He says either a headache or a stomachache seems to interfere with his work and his boss is complaining. Upon questioning he admits that he now finds his work is stressful but hadn’t a year ago, has lost weight over the past 6 months, sleeps all the time on the weekends, finds it hard to get up during the week and is bored with life. His physician rules out physical ailments with several tests and suggests a diagnosis. He recommends they try pharmacotherapy that will work to increase the action of several monoamines and that they may in turn reverse stress induced damage. What is a first line drug for his condition?
Correct Answer
E. Venlafaxine
Explanation
The patient's symptoms, including headaches, weight loss, excessive sleep, difficulty waking up, and loss of interest in life, suggest a possible diagnosis of depression. The physician recommends pharmacotherapy to increase the action of several monoamines, which are neurotransmitters involved in mood regulation. Venlafaxine is a first-line drug for depression that works by inhibiting the reuptake of both serotonin and norepinephrine, increasing their levels in the brain. This can help alleviate symptoms of depression and reverse stress-induced damage.
22.
A 19-year-old girl and her fiancé, come to see her doctor to discuss her present antiepileptic drug therapy,. They are to be married soon, and want to start a family. Her doctor discusses her present diagnosis of complex partial, and secondarily generalized tonic-clonic seizures from which she has suffered over the past three years . She was first treated with drug A which gave her severe gingival hyperplasia , acne , and mental dullness, therefore this drug was stopped. Drug A was followed by Drug B which caused her to gain weight, loose hair, and develop a tremor; Drug B was also was stopped. When she started on drug X, its plasma levels seemed to decrease very quickly and the dose had to be adjusted upwards. Drug X effectively controls her condition, and the doctor says that it is safer than some of the others in pregnancy. Which of the options below correctly identifies drug X?
Correct Answer
B. Drug X is carbamazepine
Explanation
The patient's doctor mentions that Drug X is safer than some of the others in pregnancy. This suggests that Drug X has been proven to have a lower risk of harm to the fetus compared to other antiepileptic drugs. Among the options given, carbamazepine is known to be relatively safe during pregnancy and is commonly used to treat seizures. Therefore, the correct answer is Drug X is carbamazepine.
23.
A 25-year-old women presented at the emergency room with tremors, hyperreflexia, tachycardia, mydriasis, increased bowel sounds, gait difficulties and delirium. She has a history of depression, anxiety and opiate dependence. She is currently being treated with fluoxetine, olanzepine and methadone. What best explains the symptoms she has presented with?
Correct Answer
B. Serotonin syndrome
Explanation
The symptoms presented by the patient, including tremors, hyperreflexia, tachycardia, mydriasis, increased bowel sounds, gait difficulties, and delirium, are consistent with serotonin syndrome. Serotonin syndrome is a potentially life-threatening condition that occurs due to an excess of serotonin in the body. The patient's history of depression, anxiety, and opiate dependence, as well as the medications she is currently taking (fluoxetine, olanzapine, and methadone), all contribute to an increased risk of developing serotonin syndrome. Benzodiazepine overdose, alcohol overdose, GABA syndrome, and opiate overdose do not fully explain the range of symptoms seen in this patient.
24.
A 26-year-old women presents to her primary care physician in the winter with a current complaint of a pattern of symptoms. She “hibernates” all winter and has done so since High School. She has gained weight from increased sweets, excessive alcohol use, lack of motivation, negative ruminations, and decreased productivity at work. From a complete history, she has had several episodes of increased mood with overspending and was brought to the emergency room for intoxication. Her physician recommends a specialist who confirms his diagnosis and suggests she start with which pharmacotherapy?
Correct Answer
D. Quetiapine
Explanation
The patient's symptoms, such as weight gain, excessive alcohol use, lack of motivation, negative ruminations, and decreased productivity at work, along with a history of increased mood and overspending, suggest a diagnosis of bipolar disorder with a seasonal pattern, also known as seasonal affective disorder (SAD). Quetiapine is a commonly used medication for the treatment of bipolar disorder, including SAD. It helps stabilize mood and reduce symptoms of depression and mania. Therefore, quetiapine would be an appropriate pharmacotherapy choice for this patient.
25.
When the patient, a 26 year old male medical student, exhibits intense sweating, hyperventilation and racing pulse before a test, but in other situations he is only moderately anxious and tries to maintain a healthy lifestyle which statement is most true?
Correct Answer
A. In the long term, Panic Control Treatment is most effective
Explanation
In the long term, Panic Control Treatment is most effective for the patient's symptoms of intense sweating, hyperventilation, and racing pulse before a test. This suggests that the patient may be experiencing panic attacks specifically related to test anxiety. Panic Control Treatment focuses on teaching the patient strategies to manage and reduce panic symptoms, such as breathing exercises and cognitive restructuring. It is considered the most effective approach for long-term management of panic attacks.
26.
The patient, a 37 year old female with three children, After a recent strong earthquake she has an intense fear of going in the basement of the house, and is now afraid when using the elevator to get to her work office on the 21st floor. She feels her heart racing; she perspires heavily and says the lights seem to be getting brighter and dimmer as she rides the elevator. This has been going on for the last two weeks, does not seem to be getting any better or worse during that time. Which is the best classification at this time?
Correct Answer
A. Acute Anxiety Reaction
Explanation
The best classification for the patient's symptoms at this time is Acute Anxiety Reaction. The patient is experiencing intense fear and physical symptoms such as racing heart, heavy perspiration, and changes in vision. These symptoms are consistent with an acute anxiety reaction, which is a temporary and intense reaction to a specific trigger, in this case, the recent strong earthquake. The symptoms have been ongoing for the past two weeks and do not seem to be improving or worsening. This suggests that the reaction is acute rather than a chronic disorder like Generalized Anxiety Disorder or Specific Phobia.