Red flags

Red flags US Medical PG Question 1: A 51-year-old woman is brought into the emergency department following a motor vehicle accident. She is unconscious and was intubated in the field. Past medical history is unknown. Upon arrival, she is hypotensive and tachycardic. Her temperature is 37.2°C (99.1°F), the pulse is 110/min, the respiratory rate is 22/min, and the blood pressure is 85/60 mm Hg. There is no evidence of head trauma, she withdraws to pain and her pupils are 2mm and reactive to light. Her heart has a regular rhythm without any murmurs or rubs and her lungs are clear to auscultation. Her abdomen is firm and distended with decreased bowel sounds. Her extremities are cool and clammy with weak, thready pulses. There is no peripheral edema. Of the following, what is the likely cause of her presentation?

• A. Septic shock
• B. Neurogenic shock
• C. Obstructive shock
• D. Hypovolemic shock (Correct Answer)
• E. Cardiogenic shock

Red flags Explanation: ***Hypovolemic shock*** - The patient's presentation with ***hypotension*** (BP 85/60 mm Hg), ***tachycardia*** (pulse 110/min), ***cool and clammy extremities***, ***weak peripheral pulses***, and a ***firm, distended abdomen*** after a motor vehicle accident strongly suggests internal hemorrhage leading to hypovolemic shock. - The ***firm and distended abdomen*** is a key indicator of potential intra-abdominal bleeding, significantly contributing to the loss of intravascular volume. *Septic shock* - Septic shock is characterized by signs of infection along with organ dysfunction and circulatory compromise, often presenting with **fever** or **hypothermia**, and sometimes **warm extremities** initially due to vasodilation. This patient's temperature is normal, and extremities are cool. - While hypotension and tachycardia are present, the absence of clear signs of infection and the presence of a firm, distended abdomen make hypovolemia a more immediate concern following trauma. *Neurogenic shock* - Neurogenic shock typically follows severe spinal cord injury above T6, leading to a loss of sympathetic tone. This results in **hypotension with bradycardia** and **warm, dry skin** due to widespread vasodilation. - This patient is tachycardic and has cool, clammy extremities, which contradicts the classic presentation of neurogenic shock. *Obstructive shock* - Obstructive shock occurs due to a physical obstruction to central circulation, such as **tension pneumothorax**, **cardiac tamponade**, or **pulmonary embolism**. - There is no mention of absent breath sounds, jugular venous distention, muffled heart sounds, or other specific signs pointing to an obstructive cause. Lungs are clear to auscultation and heart rhythm is regular. *Cardiogenic shock* - Cardiogenic shock results from primary cardiac dysfunction, often presenting with signs of **heart failure**, such as **pulmonary edema** (rales), **jugular venous distention**, gallop rhythms, or new murmurs. - The patient has clear lungs, a regular heart rhythm, and no murmurs, which makes primary cardiac dysfunction less likely as the immediate cause of shock in this trauma setting.

Red flags US Medical PG Question 2: A 40-year-old Caucasian male presents to the emergency room after being shot in the arm in a hunting accident. His shirt is soaked through with blood. He has a blood pressure of 65/40, a heart rate of 122, and his skin is pale, cool to the touch, and moist. This patient is most likely experiencing all of the following EXCEPT:

• A. Decreased sarcomere length in the myocardium
• B. Increased stroke volume (Correct Answer)
• C. Confusion and irritability
• D. Decreased preload
• E. Increased thromboxane A2

Red flags Explanation: ***Increased stroke volume*** - The patient is experiencing **hypovolemic shock** due to significant blood loss, meaning their **cardiac output** is severely compromised. - In shock, the heart attempts to compensate by increasing **heart rate**, but **stroke volume** is typically decreased due to reduced **preload**. *Decreased sarcomere length in the myocardium* - In situations of significant blood loss and **decreased preload**, there is less venous return to the heart, leading to reduced end-diastolic volume. - According to the **Frank-Starling law**, reduced end-diastolic volume results in shorter initial sarcomere length, which reduces the force of contraction and thus, **stroke volume**. *Confusion and irritability* - **Hypovolemic shock** leads to widespread **tissue hypoperfusion**, especially to vital organs like the brain. - Reduced cerebral blood flow results in impaired brain function, manifesting as **confusion, irritability**, and altered mental status. *Decreased preload* - Significant blood loss leads to a reduction in the **total circulating blood volume**. - This reduction directly decreases the venous return to the heart, thus lowering the **end-diastolic volume** and subsequently, the **preload**. *Increased thromboxane A2* - In response to **vascular injury and bleeding**, the body initiates hemostasis, a critical component of which is platelet aggregation. - **Thromboxane A2** is a potent vasoconstrictor and platelet aggregator released by activated platelets to form a **platelet plug** and help stop bleeding.

Red flags US Medical PG Question 3: A 15-year-old boy is brought to the emergency department one hour after sustaining an injury during football practice. He collided head-on into another player while wearing a mouthguard and helmet. Immediately after the collision he was confused but able to use appropriate words. He opened his eyes spontaneously and followed commands. There was no loss of consciousness. He also had a headache with dizziness and nausea. He is no longer confused upon arrival. He feels well. Vital signs are within normal limits. He is fully alert and oriented. His speech is organized and he is able to perform tasks demonstrating full attention, memory, and balance. Neurological examination shows no abnormalities. There is mild tenderness to palpation over the crown of his head but no signs of skin break or fracture. Which of the following is the most appropriate next step?

• A. Discharge without activity restrictions
• B. Discharge and refrain from all physical activity for one week
• C. Observe for 6 hours in the ED and refrain from contact sports for one week (Correct Answer)
• D. Administer prophylactic levetiracetam and observe for 24 hours
• E. Administer prophylactic phenytoin and observe for 24 hours

Red flags Explanation: ***Observe for 6 hours in the ED and refrain from contact sports for one week*** - This patient experienced a brief period of **confusion, headache, dizziness**, and **nausea** immediately after a head injury, which are symptoms consistent with a **mild traumatic brain injury (mTBI)** or **concussion**. - Although his symptoms have resolved at presentation, observation in the ED for a few hours is prudent to ensure no delayed onset of more severe symptoms, and he should **refrain from contact sports** for at least one week as part of concussion management. *Discharge without activity restrictions* - Discharging without activity restrictions is unsafe given the initial symptoms of **confusion** and the potential for delayed symptom presentation or complications from a concussion. - Concussion management requires a period of **physical and cognitive rest** to allow the brain to heal and prevent **second impact syndrome**. *Discharge and refrain from all physical activity for one week* - While refraining from all physical activity for one week is part of concussion management, discharging immediately without any observation period after initial neurological symptoms could be risky. - An observation period allows for monitoring of any **worsening neurological signs** or symptoms that might indicate a more serious injury. *Administer prophylactic levetiracetam and observe for 24 hours* - **Prophylactic anticonvulsants** like levetiracetam are typically not recommended for routine management of **mild traumatic brain injury** or concussion. - Their use is generally reserved for patients with more severe injuries, evolving conditions, or those who have had **seizures post-trauma**. *Administer prophylactic phenytoin and observe for 24 hours* - Similar to levetiracetam, **phenytoin** is an anticonvulsant and its prophylactic use is not indicated for **mild head injuries** or concussions. - Anticonvulsant prophylaxis is associated with potential side effects and is reserved for specific high-risk scenarios, such as **severe TBI** or **penetrating head trauma**.

Red flags US Medical PG Question 4: A 6-month-old male presents to the emergency department with his parents after his three-year-old brother hit him on the arm with a toy truck. His parents are concerned that the minor trauma caused an unusual amount of bruising. The patient has otherwise been developing well and meeting all his milestones. His parents report that he sleeps throughout the night and has just started to experiment with solid food. The patient’s older brother is in good health, but the patient’s mother reports that some members of her family have an unknown blood disorder. On physical exam, the patient is agitated and difficult to soothe. He has 2-3 inches of ecchymoses and swelling on the lateral aspect of the left forearm. The patient has a neurological exam within normal limits and pale skin with blue irises. An ophthalmologic evaluation is deferred. Which of the following is the best initial step?

• A. Genetic testing
• B. Complete blood count and coagulation panel (Correct Answer)
• C. Ensure the child's safety and alert the police
• D. Peripheral blood smear
• E. Hemoglobin electrophoresis

Red flags Explanation: ***Complete blood count and coagulation panel*** - The unusual amount of **bruising** after minor trauma, along with a family history of an unknown blood disorder, strongly suggests a potential **bleeding disorder**. A **CBC** and a **coagulation panel** (PT, aPTT, fibrinogen) are essential initial steps to evaluate for abnormalities in platelets, clotting factors, or other hematologic conditions. - These tests can help narrow down the differential diagnosis between **platelet dysfunction**, **coagulopathies** (like hemophilia or von Willebrand disease), or other less common bleeding disorders, guiding further specific investigations. - **Important consideration:** The presence of **blue sclera** (described as "blue irises") raises concern for **osteogenesis imperfecta (OI)**, a connective tissue disorder causing bone fragility. However, initial hematologic screening is still appropriate given the family history of blood disorder and presentation of excessive bruising. If coagulation studies are normal, imaging and further workup for OI would be indicated. *Genetic testing* - While a genetic component is plausible given the patient's family history and clinical presentation (blue sclera may suggest osteogenesis imperfecta), **genetic testing** is typically performed *after* initial laboratory workup has identified a specific type of bleeding or inherited disorder. - Starting with genetic testing without basic hematologic parameters is not the most efficient or cost-effective initial diagnostic approach. *Ensure the child's safety and alert the police* - While child abuse should always be considered in cases of unexplained or excessive bruising, the presence of a **family history of a blood disorder** and the **blue sclera** (suggesting possible osteogenesis imperfecta) make **medical causes** more immediate concerns for initial investigation. - Pursuing a medical workup first often clarifies whether abuse is the primary explanation, although child protective services should be notified if suspicion remains high after medical evaluation. *Peripheral blood smear* - A **peripheral blood smear** provides information on red blood cell morphology, platelet size and number, and white blood cell differential. While useful in assessing for some hematologic conditions, it is often performed *after* a CBC has indicated abnormalities or in conjunction with specialized testing. - It would not be the *best initial step* as it doesn't directly assess clotting factor function, which is critical in evaluating significant bruising severity. *Hemoglobin electrophoresis* - **Hemoglobin electrophoresis** is used to diagnose **hemoglobinopathies** like sickle cell anemia or thalassemia. - The patient's symptoms (easy bruising) are not characteristic of hemoglobinopathies, and while he has pale skin, this test would not be the initial step to investigate a bleeding disorder.

Red flags US Medical PG Question 5: A 68-year-old woman presents to the hospital for an elective right hemicolectomy. She is independently mobile and does her own shopping. She has had type 2 diabetes mellitus for 20 years, essential hypertension for 15 years, and angina on exertion for 6 years. She has a 30-pack-year history of smoking. The operation was uncomplicated. On post-op day 5, she becomes confused. She has a temperature of 38.5°C (101.3°F), respiratory rate of 28/min, and oxygen saturation of 92% on 2 L of oxygen. She is tachycardic at 118/min and her blood pressure is 110/65 mm Hg. On chest auscultation, she has coarse crackles in the right lung base. Her surgical wound appears to be healing well, and her abdomen is soft and nontender. Which of the following is the most likely diagnosis?

• A. Malignant hyperthermia
• B. Drug-induced fever
• C. Multiple organ dysfunction syndrome
• D. Sepsis (Correct Answer)
• E. Non-infectious systemic inflammatory response syndrome (SIRS)

Red flags Explanation: ***Sepsis*** - The patient exhibits several signs of **systemic inflammatory response syndrome (SIRS)** (fever, tachycardia, tachypnea) coupled with evidence of infection (coarse crackles in the lung base suggests **pneumonia**). - The combination of **SIRS criteria** and a likely infection source in a postoperative patient strongly points to sepsis, a life-threatening organ dysfunction caused by a dysregulated host response to infection. *Malignant hyperthermia* - This is a rare, life-threatening condition typically triggered by **volatile anesthetic agents** or **succinylcholine** during surgery. - It usually presents **intraoperatively or immediately postoperatively** with rapid onset of hyperthermia, muscle rigidity, and metabolic acidosis, which is not consistent with a presentation on post-op day 5. *Drug-induced fever* - While drug-induced fever is possible, particularly in polymedicated patients, it would be a **diagnosis of exclusion** when other more likely causes of fever, such as infection, are present. - There are no specific clinical features in this case that strongly suggest a drug as the singular cause of fever and the systemic inflammatory response. *Multiple organ dysfunction syndrome* - **MODS** is the progressive failure of two or more organ systems and is often a **complication of severe sepsis or septic shock**, rather than an initial diagnosis. - While the patient is unwell, her current presentation describes a potential precursor (sepsis) rather than established multi-organ dysfunction. *Non-infectious systemic inflammatory response syndrome (SIRS)* - SIRS caused by non-infectious etiologies (e.g., pancreatitis, trauma, burns) can occur, but the presence of **localized lung crackles** and a **postoperative fever** makes an infectious etiology much more likely. - Postoperative SIRS can occur due to surgical stress, but the signs of infection (especially respiratory) shift the diagnosis towards sepsis.

Red flags US Medical PG Question 6: A 65-year-old man presents to the emergency department for sudden weakness. He was doing mechanical work on his car where he acutely developed right-leg weakness and fell to the ground. He is accompanied by his wife, who said that this has never happened before. He was last seen neurologically normal approximately 2 hours prior to presentation. His past medical history is significant for hypertension and type II diabetes. His temperature is 98.8°F (37.1°C), blood pressure is 177/108 mmHg, pulse is 90/min, respirations are 15/min, and oxygen saturation is 99% on room air. Neurological exam reveals that he is having trouble speaking and has profound weakness of his right upper and lower extremity. Which of the following is the best next step in management?

• A. Thrombolytics
• B. Noncontrast head CT (Correct Answer)
• C. CT angiogram
• D. MRI of the head
• E. Aspirin

Red flags Explanation: ***Noncontrast head CT*** - A **noncontrast head CT** is the most crucial initial step in managing acute stroke symptoms because it can rapidly rule out an **intracranial hemorrhage**. - Distinguishing between ischemic stroke and hemorrhagic stroke is critical, as the management strategies are vastly different and administering thrombolytics in the presence of hemorrhage can be fatal. *Thrombolytics* - **Thrombolytics** can only be administered after an **intracranial hemorrhage** has been excluded via noncontrast head CT. - Administering thrombolytics without imaging could worsen a hemorrhagic stroke, causing significant harm or death. *CT angiogram* - A **CT angiogram** is used to identify large vessel occlusions in ischemic stroke and is typically performed after a noncontrast CT rules out hemorrhage. - This imaging is crucial for determining eligibility for **endovascular thrombectomy** but is not the very first diagnostic step. *MRI of the head* - An **MRI of the head** is more sensitive for detecting acute ischemic changes but takes longer to perform and is often not readily available in the acute emergency setting. - It is not the initial imaging of choice for ruling out hemorrhage due to its longer acquisition time compared to CT. *Aspirin* - **Aspirin** is indicated for acute ischemic stroke but should only be given after an **intracranial hemorrhage** has been ruled out. - Like thrombolytics, aspirin could exacerbate a hemorrhagic stroke and is thus deferred until initial imaging is complete.

Red flags US Medical PG Question 7: A 65-year-old woman is brought to the emergency department by her husband due to difficulty speaking and confusion for 1 hour. She was gardening when she suddenly developed these symptoms. She is not able to respond to the questions despite multiple repetitions. She also appears unsteady with her gait and is able to walk with support. The past medical history includes type 2 diabetes mellitus, dyslipidemia, and osteoarthritis. The medicine list includes aspirin, atorvastatin, metformin, and chondroitin sulfate. The vital signs include: blood pressure 174/88 mm Hg, heart rate 154/min and irregular, respiratory rate 12/min, and oxygen saturation 96% on room air. She is awake, but not following commands. The pupils are equal bilaterally and reactive to light. There is mild facial droop on the right side. The forehead wrinkles are preserved. When the soles of her feet are stimulated with a blunt instrument, the right-sided big toe goes upward, while the left-sided big toe goes downward. The ECG shows variable R-R intervals and absence of P waves. What is the next step in the management of this patient?

• A. MRI of the head
• B. Echocardiography
• C. Amiodarone
• D. Aspirin
• E. CT scan of the head (Correct Answer)

Red flags Explanation: ***CT scan of the head*** - This patient presents with acute neurological deficits suggestive of a **stroke**, including difficulty speaking, confusion, facial droop, and Babinski sign (right-sided big toe going upward). - An **urgent non-contrast CT scan of the head** is the immediate next step to differentiate between an ischemic stroke and a hemorrhagic stroke, which dictates subsequent management. *MRI of the head* - While an **MRI** can provide more detailed imaging of brain tissue, it is **not the initial imaging modality** of choice in acute stroke due to longer acquisition times and limited availability. - CT is faster and readily available in most emergency settings, making it crucial for timely decision-making. *Echocardiography* - **Echocardiography** would be considered later in the workup to identify a potential **cardiac source of emboli**, such as left atrial appendage thrombus in the context of atrial fibrillation. - However, it is **not the immediate next step** as it does not help differentiate between ischemic and hemorrhagic stroke, which is critical for acute management. *Amiodarone* - The patient's irregular heart rate and absent P waves are highly suggestive of **atrial fibrillation with rapid ventricular response**. - While **amiodarone** can be used for rhythm or rate control in atrial fibrillation, addressing the acute stroke and determining its type (ischemic vs. hemorrhagic) takes **precedence** over cardiac rhythm management. *Aspirin* - **Aspirin** is indicated for the acute management of **ischemic stroke** to prevent further clot formation. - However, administering aspirin to a patient with a **hemorrhagic stroke** could worsen bleeding and be devastating, hence the critical need for a CT scan first.

Red flags US Medical PG Question 8: A 48-year-old man with a history of nephrolithiasis presents with acute-onset left flank pain. He says that the pain started suddenly 4 hours ago and has progressively worsened. He describes the pain as severe, sharp, and localized to the left flank. The patient denies any fever, chills, nausea, vomiting, or dysuria. His past medical history is significant for nephrolithiasis diagnosed 4 years ago status post shockwave lithotripsy. The patient says, "I’m allergic to many pain medications, but there is one that I get all the time when I have this pain. I think it starts with D". He is afebrile and his vital signs are stable. On physical examination, he is writhing in pain and moaning. Exquisite left costovertebral angle tenderness is noted. Laboratory findings, including a urinalysis, are unremarkable. IV fluid resuscitation is administered. Which of the following is the best next step in the management of this patient?

• A. Non-contrast CT of the abdomen and pelvis
• B. Administer ibuprofen and acetaminophen for pain control (Correct Answer)
• C. Administer dilaudid (hydromorphone) for pain control
• D. Discharge patient with prescription of dilaudid with follow-up in 3 months
• E. Admit to hospital floor for IV dilaudid patient-controlled analgesia

Red flags Explanation: ***Administer ibuprofen and acetaminophen for pain control*** - In acute renal colic with severe pain, **immediate pain management is the priority** before diagnostic imaging, especially in a hemodynamically stable patient without signs of infection or complications. - **NSAIDs (ibuprofen) are first-line therapy** per American Urological Association (AUA) and European Association of Urology (EAU) guidelines for acute renal colic, as they reduce pain and decrease ureteral spasm. - Acetaminophen provides additional analgesia through a different mechanism and is safe to combine with NSAIDs. - The patient's mention of "allergies to many pain medications" does not contraindicate a trial of NSAIDs and acetaminophen, which are generally well-tolerated. The reference to "D" medication is a distractor suggesting opioid-seeking behavior. - **Non-contrast CT will still be performed**, but after addressing the acute pain crisis - this is patient-centered, evidence-based care. *Non-contrast CT of the abdomen and pelvis* - While this is the **gold standard for diagnosing nephrolithiasis** and will be needed to confirm stone size, location, and complications, it is **not the immediate next step** in a patient writhing in severe pain. - The clinical presentation (acute flank pain, CVA tenderness, history of stones, normal UA, stable vitals) is classic for uncomplicated renal colic. - Modern clinical practice prioritizes **pain control first, then imaging** - delaying analgesia to obtain a CT first is not appropriate emergency management. - CT should be performed after initiating pain management to guide definitive treatment decisions. *Administer dilaudid (hydromorphone) for pain control* - While opioids like dilaudid can be used for renal colic, **NSAIDs are preferred first-line therapy** as they are equally or more effective for renal colic pain and have fewer side effects. - The patient's hint about "D" medication may suggest drug-seeking behavior, making it more appropriate to start with non-opioid analgesics. - Opioids should be reserved for cases where NSAIDs are contraindicated or ineffective after trial. *Discharge patient with prescription of dilaudid with follow-up in 3 months* - Discharging a patient with **severe, acute, undiagnosed pain** without imaging or confirmed diagnosis is unsafe and inappropriate. - The patient requires diagnostic imaging (CT) after pain control to assess stone burden, size, location, and likelihood of spontaneous passage. - Follow-up in 3 months is far too delayed - patients with acute renal colic need reassessment within days to weeks depending on stone characteristics. *Admit to hospital floor for IV dilaudid patient-controlled analgesia* - Admission is premature before attempting outpatient pain management and obtaining diagnostic imaging. - Most patients with uncomplicated renal colic can be managed in the emergency department with oral analgesics and discharged with close follow-up. - Admission criteria include: intractable pain/vomiting, suspected infection, acute kidney injury, solitary kidney, or stones unlikely to pass spontaneously. - Starting with PCA opioids bypasses appropriate first-line NSAID therapy.

Red flags US Medical PG Question 9: An 82-year-old male visits his primary care physician for a check-up. He reports that he is in his usual state of health. His only new complaint is that he feels as if the room is spinning, which has affected his ability to live independently. He is currently on lisinopril, metformin, aspirin, warfarin, metoprolol, and simvastatin and says that he has been taking them as prescribed. On presentation, his temperature is 98.8°F (37°C), blood pressure is 150/93 mmHg, pulse is 82/min, and respirations are 12/min. On exam he has a left facial droop and his speech is slightly garbled. Eye exam reveals nystagmus with certain characteristics. The type of nystagmus seen in this patient would most likely also be seen in which of the following diseases?

• A. Benign paroxysmal positional vertigo
• B. Multiple sclerosis (Correct Answer)
• C. Meniere disease
• D. Vestibular neuritis
• E. Aminoglycoside toxicity

Red flags Explanation: ***Multiple sclerosis*** - This patient's presentation (acute vertigo, left facial droop, dysarthria, and nystagmus in an elderly patient with vascular risk factors) is most consistent with a **brainstem stroke** affecting the posterior circulation. - The nystagmus in this case is **central nystagmus**, characterized by being non-fatigable, multidirectional, and not suppressed by visual fixation—typical of **CNS lesions** affecting the brainstem or cerebellum. - **Multiple sclerosis** also causes **central nystagmus** due to demyelinating plaques in the brainstem, cerebellum, or medial longitudinal fasciculus, making it the condition that would exhibit the same type of nystagmus pattern. - Both brainstem stroke and MS produce central vestibular dysfunction with similar nystagmus characteristics. *Benign paroxysmal positional vertigo* - BPPV causes **peripheral nystagmus** that is fatigable, triggered by specific head positions, and typically resolves within 30-60 seconds. - The nystagmus is usually **rotatory or torsional** and follows a predictable pattern with the Dix-Hallpike maneuver. - This patient's persistent symptoms and additional neurological signs (facial droop, dysarthria) indicate a **central, not peripheral**, cause. *Meniere disease* - Meniere's disease causes **peripheral nystagmus** associated with episodic vertigo, fluctuating hearing loss, tinnitus, and aural fullness. - The nystagmus in Meniere's is typically **horizontal** during acute attacks but does not present with focal neurological deficits like facial weakness or speech changes. - This patient lacks the classic auditory symptoms and has clear signs of a **central lesion**. *Vestibular neuritis* - Vestibular neuritis results from inflammation of the vestibular nerve, causing **peripheral nystagmus** that is horizontal-torsional, unidirectional, and enhanced without visual fixation. - It typically presents with acute severe vertigo following a viral illness, without other neurological signs. - The presence of **facial droop and dysarthria** in this patient rules out a purely peripheral vestibular disorder. *Aminoglycoside toxicity* - Aminoglycosides cause **bilateral vestibulotoxicity**, leading to oscillopsia, chronic dysequilibrium, and possible hearing loss, but not acute vertigo with nystagmus. - When present, the vestibular dysfunction is typically **bilateral and symmetric**, without spontaneous nystagmus at rest. - This patient is not on aminoglycosides, and his presentation with focal neurological signs points to a **central structural lesion** rather than toxic peripheral vestibulopathy.

Red flags US Medical PG Question 10: A 21-year-old man presents with fever, headache, and clouded sensorium for the past 3 days. His fever is low-grade. He says his headache is mild-to-moderate in intensity and associated with nausea, vomiting, and photophobia. There is no history of a sore throat, pain on urination, abdominal pain, or loose motions. He smokes 1–2 cigarettes daily and drinks alcohol socially. Past medical history and family history are unremarkable. His vital signs include: blood pressure 120/80 mm Hg, pulse 106/min, temperature 37.3°C (99.2°F). On physical examination, he is confused, disoriented, and agitated. Extraocular movements are intact. The neck is supple on flexion. He is moving all his 4 limbs spontaneously. A noncontrast CT scan of the head is within normal limits. A lumbar puncture is performed, and cerebrospinal fluid results are still pending. The patient is started on empiric intravenous acyclovir. Which of the following clinical features favors encephalitis rather than meningitis?

• A. Photophobia
• B. Clouded sensorium (Correct Answer)
• C. Headache
• D. Fever
• E. Nausea and vomiting

Red flags Explanation: ***Clouded sensorium*** - **Altered mental status**, including confusion, disorientation, agitation, and clouded sensorium, is the hallmark feature that distinguishes **encephalitis** from meningitis - **Encephalitis** involves direct inflammation of the **brain parenchyma**, leading to impaired brain function and altered consciousness - While meningitis can cause irritability, profound changes in consciousness like disorientation and confusion are characteristic of **brain tissue involvement** rather than isolated meningeal inflammation - The patient's confusion, disorientation, and agitation indicate parenchymal dysfunction, making encephalitis the more likely diagnosis *Photophobia* - Photophobia is a common symptom in **both meningitis and encephalitis**, reflecting meningeal irritation - It results from inflammation of the meninges and does not indicate brain parenchymal involvement - This symptom is **not a differentiating factor** between the two conditions *Headache* - Headache is a prominent symptom in **both meningitis and encephalitis** due to meningeal inflammation and increased intracranial pressure - While often severe in meningitis, it can also occur in encephalitis when meningeal irritation is present (meningoencephalitis) - Headache alone **does not specifically favor** one diagnosis over the other *Fever* - Fever is a systemic response to infection and inflammation, present in **both meningitis and encephalitis** - It reflects the body's immune response to the infectious agent - The presence of fever **does not help distinguish** between inflammation of the meninges alone versus inflammation involving the brain parenchyma *Nausea and vomiting* - Nausea and vomiting can occur in **both meningitis and encephalitis**, often associated with meningeal irritation and increased intracranial pressure - These symptoms result from stimulation of the vomiting center and are common in many CNS infections - These symptoms are **not specific enough to differentiate** between the two conditions

Red flags Flashcard 1 of 10

Question: Varicocele is associated with left-sided _____ carcinoma

Answer: renal cell

Red flags Flashcard 2 of 10

Question: A retropharyngeal abscess commonly presents with fever, _____ pain, drooling, and cervical lymphadenopathy

Answer: neck

Red flags Flashcard 3 of 10

Question: What are the signs and symptoms of stage 2 Lyme disease?

Answer: bilateral facial nerve palsy, AV node block

Red flags Flashcard 4 of 10

Question: Paraesophageal hernias are associated with _____ in lung fields

Answer: bowel sounds

Extra Information:   Watch Structural Esophageal Disorders & GERD [https://dashboard.sketchy.com/study/medical/courses/medical-pathophysiology/units/medical-pathophysiology-gi/videos/medical-pathophysiology-gi-esophageal-and-gastric-disorders-structural-esophageal-disorders-and-gerd?utm_source=anki&utm_medium=partnership&utm_campaign=february_update&utm_content=medical]Watch associated Bootcamp video [https://app.bootcamp.com/med-school/gastroenterology/videos/non-visceral-anatomy?index=6] https://onlinemeded.org?ref=anki Atlas: 

Red flags Flashcard 5 of 10

Question: Spinal metastases present with back pain that is worse at _____, and is not relieved by position changes / analgesics

Answer: night

Extra Information:  https://onlinemeded.org?ref=anki 

Red flags Flashcard 6 of 10

Question: PSA > _____ ng/dl is worrisome at any age and may be indicative of prostatic adenocarcinoma

Answer: 10

Extra Information:   Watch Benign Prostatic Hyperplasia (BPH) & Prostate Cancer [https://dashboard.sketchy.com/study/medical/courses/medical-pathophysiology/units/medical-pathophysiology-reproductive-gu/videos/medical-pathophysiology-reproductive-and-gu-male-gu-benign-prostatic-hyperplasia-bph-and-prostate-cancer?utm_source=anki&utm_medium=partnership&utm_campaign=february_update&utm_content=medical] https://onlinemeded.org/spa/renal/prostate/acquire?ref=anki 

Red flags Flashcard 7 of 10

Question: Cardiovascular collapse, hyponatremia, hypoglycemia, adrenal insufficiency, and hypothermia/confusion are complications seen in _____

Answer: myxedema coma

Extra Information:  * Adrenal insufficiency (broken adrenal beanie cap) associated with myxedema coma, as well Watch Hypothyroidism Overview & Hashimotos Thyroiditis [https://dashboard.sketchy.com/study/medical/courses/medical-pathophysiology/units/medical-pathophysiology-endocrine/videos/medical-pathophysiology-endocrine-thyroid-and-parathyroid-hypothyroidism-overview-and-hashimotos-thyroiditis?utm_source=anki&utm_medium=partnership&utm_campaign=february_update&utm_content=medical] https://onlinemeded.org/spa/endocrine?ref=anki 

Red flags Flashcard 8 of 10

Question: Cauda equina syndrome may present with absent _____ and ankle reflexes

Answer: knee

Extra Information:  Watch associated Bootcamp video [https://app.bootcamp.com/med-school/neurology/videos/spinal-cord-syndromes?index=6] https://onlinemeded.org/spa/neurology?ref=anki Other: 

Red flags Flashcard 9 of 10

Question: As limb compartment syndrome progresses, patients can develop _____ deficits

Answer: motor

Extra Information:  https://onlinemeded.org?ref=anki 

Red flags Flashcard 10 of 10

Question: Ependymomas may present with _____

Answer: hydrocephalus

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