A 44-year-old woman presents to her primary care physician’s office with episodes of pain in her right hand. She says that the pain is most significant at night and awakens her from sleep numerous times. When she experiences this pain, she immediately puts her hand under warm running water or shakes her hand. She has also experienced episodes of numbness in the affected hand. Driving and extending the right arm also provoke her symptoms. She denies any trauma to the hand or associated weakness. Medical history is notable for hypothyroidism treated with levothyroxine. She works as a secretary for a law firm. On physical exam, when the patient hyperflexes her wrist, pain and paresthesia affect the first 3 digits of the right hand. Which of the following is the confirmatory diagnostic test for this patient?
Q72
An 81-year-old man comes to the physician because of increased exertional dyspnea and dizziness over the past 8 weeks. He has hypertension for which he takes lisinopril. He has smoked one pack of cigarettes daily for the past 50 years. Physical examination shows weak peripheral pulses. Cardiac examination is shown. Which of the following is the most likely diagnosis?
Q73
A 31-year-old woman presents to the physician for a routine health maintenance examination. She feels well and has no current complaints. She has no history of serious illness and takes no medications. The vital signs include: blood pressure 185/110 mm Hg, pulse 75/min, and respiration rate 12/min. Her high blood pressure is confirmed during a 2nd visit. Neurologic examination shows no abnormalities. Careful auscultation of the abdomen reveals bruits in both upper quadrants near the midline. The remainder of the physical exam is unremarkable. The results of a complete blood count (CBC), renal function panel, and urinalysis showed no abnormalities. Conventional angiography confirms bilateral disease involvement. To control this patient’s hypertension, it is most appropriate to recommend which of the following?
Q74
A 65-year-old woman presents to the clinic for a routine checkup. She has unintentionally lost 4.5 kg (9.9 lb) in the past month but denies any other complaints. Her pulse rate is 90/min, respiratory rate is 18/min, temperature is 37.0°C (98.6°F), and blood pressure is 150/70 mm Hg. An irregularly irregular rhythm is heard on auscultation of the heart. Neck examination shows a markedly enlarged thyroid with no lymphadenopathy or bruit. Laboratory tests show low serum thyroid-stimulating hormone level, high T4 level, absent thyroid-stimulating immunoglobulin, and absent anti-thyroid peroxidase antibody. Nuclear scintigraphy shows patchy uptake with multiple hot and cold areas. Which of the following is the most likely diagnosis?
Q75
A 66-year old man comes to the physician because of fatigue for 6 months. He says that he wakes up every morning feeling tired. Most days of the week he feels sleepy during the day and often takes an afternoon nap for an hour. His wife says he snores in the middle of the night. He has a history of heart failure and atrial fibrillation. His medications include aspirin, atorvastatin, lisinopril, metoprolol, and warfarin. He drinks 1–2 glasses of wine daily with dinner; he does not smoke. He is 175 cm (5 ft 9 in) tall and weighs 96 kg (212 lb); BMI is 31.3 kg/m2. His blood pressure is 142/88 mm Hg, pulse is 98/min, and respirations are 22/min. Examination of the oral cavity shows a low-lying palate. Cardiac examination shows an irregularly irregular rhythm and no murmurs. The remainder of the examination shows no abnormalities. Which of the following is the most appropriate next step in management?
Q76
A 73-year-old male is brought into the ED unconscious with cold, clammy skin. His blood pressure is 65 over palpable. There are no signs of blood loss. You recognize the patient is in acute shock and blood is drawn for investigation as resuscitation is initiated. Which of the following might you expect in your laboratory investigation for this patient?
Q77
A 14-year-old boy is brought to the emergency department from school after falling in gym class. He was unable to stand after the accident and has a painful and swollen knee. On presentation he says that he has never had an incident like this before; however, he does suffer from hard to control nosebleeds and prolonged bleeding after minor cuts. Based on his presentation a panel of bleeding tests is obtained with the following results:
Bleeding time: Prolonged
Prothrombin time: Normal
Partial thromboplastin time: Prolonged
Which of the following describes the function of the component that is defective in the most likely cause of this patient's symptoms?
Q78
A 66-year-old man is brought to the emergency department because of fever, chills, and altered mental status for 3 days. According to his daughter, he has had a productive cough during this period. He has type 2 diabetes, hypertension, hypercholesterolemia, peripheral neuropathic pain, and a history of deep vein thromboses. Current medications include insulin, lisinopril, atorvastatin, warfarin, and carbamazepine. He is oriented only to self. His temperature is 39.3°C (102.7°F), pulse is 110/min, respirations are 26/min, and blood pressure is 86/50 mm Hg. Physical examination shows ecchymoses on both lower extremities. Crackles are heard at the right lung base. Laboratory studies show:
Hemoglobin 11.1 g/dL
Leukocyte count 18,000/mm3
Platelet count 45,000/mm3
Prothrombin time 45 sec
Partial thromboplastin time 75 sec
Serum
Na+ 135 mEq/L
K+ 5.4 mEq/L
Cl- 98 mEq/L
Urea nitrogen 46 mg/dL
Glucose 222 mg/dL
Creatinine 3.3 mg/dL
Which of the following is the most likely cause of this patient's ecchymoses?
Q79
A 27-year-old man is brought to the emergency department with his family because of abdominal pain, excessive urination and drowsiness since the day before. He has had type 1 diabetes mellitus for 2 years. He ran out of insulin 2 days ago. His vital signs at admission include a temperature of 36.8°C (98.24°F), a blood pressure of 102/69 mmHg, and a pulse of 121/min. On physical examination, he is lethargic and his breathing is rapid and deep. There is a mild generalized abdominal tenderness without rebound tenderness or guarding. His serum glucose is 480 mg/dL. The patient is admitted to the intensive care unit and management is started. Which of the following is considered a resolution criterion for this patient's condition?
Q80
A 25-year-old man comes to the physician because of a severe headache for 1 hour. Every day of the past week, he has experienced 3–4 episodes of severe pain over his left forehead. Each episode lasts around 30–45 minutes, and he reports pacing around restlessly during these episodes. He has been using acetaminophen for these episodes, but it has provided only minimal relief. He works as a financial analyst and says his job is very stressful. He had experienced similar symptoms 4 months ago but did not seek treatment at that time. He has no history of serious illness and takes no other medications. He has smoked one pack of cigarettes daily for 7 years. He appears anxious. Vital signs are within normal limits. There is conjunctival injection and tearing of the left eye. The remainder of the physical examination is unremarkable. Which of the following measures is most likely to provide acute relief of this patient's headaches?
Cardiology US Medical PG Practice Questions and MCQs
Question 71: A 44-year-old woman presents to her primary care physician’s office with episodes of pain in her right hand. She says that the pain is most significant at night and awakens her from sleep numerous times. When she experiences this pain, she immediately puts her hand under warm running water or shakes her hand. She has also experienced episodes of numbness in the affected hand. Driving and extending the right arm also provoke her symptoms. She denies any trauma to the hand or associated weakness. Medical history is notable for hypothyroidism treated with levothyroxine. She works as a secretary for a law firm. On physical exam, when the patient hyperflexes her wrist, pain and paresthesia affect the first 3 digits of the right hand. Which of the following is the confirmatory diagnostic test for this patient?
A. Magnetic resonance imaging
B. Needle electromyography
C. Nerve conduction studies (Correct Answer)
D. Nerve biopsy
E. Tinel test
Explanation: ***Nerve conduction studies***
- **Nerve conduction studies (NCS)** are the most sensitive and specific diagnostic test for **carpal tunnel syndrome**, definitively confirming median nerve compression.
- They measure the speed and amplitude of electrical signals through the **median nerve** at the wrist, identifying slowed conduction across the carpal tunnel.
*Magnetic resonance imaging*
- While MRI can visualize soft tissues and nerve pathology, it is not typically the **first-line confirmatory test** for carpal tunnel syndrome due to its lower sensitivity compared to NCS.
- MRI is more useful for identifying **structural abnormalities** like tumors or synovitis, which might cause secondary nerve compression.
*Needle electromyography*
- **Electromyography (EMG)** involves inserting a needle into muscles to assess their electrical activity; it helps evaluate for **axonopathy** and muscle denervation.
- While EMG is often performed alongside NCS, it primarily assesses muscle function and nerve damage severity, rather than directly confirming nerve compression itself, which is best done by NCS.
*Nerve biopsy*
- **Nerve biopsy** is an invasive procedure generally reserved for diagnosing demyelinating or infiltrative neuropathies when less invasive tests are inconclusive.
- It carries risks and is **unnecessary** and inappropriate for diagnosing a common compressive neuropathy like carpal tunnel syndrome.
*Tinel test*
- The **Tinel test** is a clinical provocative maneuver where percussion over the median nerve at the wrist elicits tingling or pain.
- It is a **screening tool** and part of the physical exam for carpal tunnel syndrome, but it is not a confirmatory diagnostic test due to its variable sensitivity and specificity.
Question 72: An 81-year-old man comes to the physician because of increased exertional dyspnea and dizziness over the past 8 weeks. He has hypertension for which he takes lisinopril. He has smoked one pack of cigarettes daily for the past 50 years. Physical examination shows weak peripheral pulses. Cardiac examination is shown. Which of the following is the most likely diagnosis?
A. Tricuspid stenosis
B. Mitral regurgitation
C. Aortic regurgitation
D. Pulmonary regurgitation
E. Aortic stenosis (Correct Answer)
Explanation: ***Aortic stenosis***
- The patient's age (81 years), history of **hypertension** and **smoking**, and symptoms of **exertional dyspnea** and **dizziness** suggest reduced cardiac output due to a fixed left ventricular outflow obstruction.
- **Weak peripheral pulses** are the pathognomonic sign of severe aortic stenosis, representing **pulsus parvus et tardus** (small and delayed pulse) due to reduced stroke volume and slow ventricular ejection through the narrowed valve.
- The cardiac examination would typically reveal a harsh **crescendo-decrescendo systolic ejection murmur** best heard at the right upper sternal border, radiating to the carotids.
- Classic triad of severe AS: **exertional dyspnea** (heart failure), **dizziness/syncope** (decreased cerebral perfusion), and angina (increased myocardial oxygen demand).
*Tricuspid stenosis*
- This is a rare condition usually associated with **rheumatic heart disease** or carcinoid syndrome, neither of which is suggested in this case.
- Presents with signs of **right-sided heart failure** (jugular venous distension, hepatomegaly, ascites, peripheral edema) rather than exertional dyspnea and dizziness.
- Would not cause weak peripheral pulses.
*Mitral regurgitation*
- Characterized by a **holosystolic murmur** radiating to the axilla, not the findings expected in this case.
- While chronic severe MR can cause exertional dyspnea, it does not typically produce **weak peripheral pulses** as a primary finding.
- Peripheral pulses are usually normal or even hyperdynamic in acute MR.
*Aortic regurgitation*
- This condition presents with a **diastolic decrescendo murmur** and characteristically **bounding, wide pulse pressure** (water-hammer or Corrigan pulse), which is the opposite of the weak peripheral pulses described.
- While severe AR can cause exertional dyspnea, the pulse examination finding directly contradicts this diagnosis.
- Other signs would include head bobbing (de Musset sign) and nail bed pulsations (Quincke pulse).
*Pulmonary regurgitation*
- Usually asymptomatic or presents with signs of **right heart failure** (peripheral edema, hepatomegaly, ascites).
- Would not explain the exertional dyspnea, dizziness, or weak peripheral pulses seen in this patient.
- Typically occurs secondary to pulmonary hypertension or congenital heart disease.
Question 73: A 31-year-old woman presents to the physician for a routine health maintenance examination. She feels well and has no current complaints. She has no history of serious illness and takes no medications. The vital signs include: blood pressure 185/110 mm Hg, pulse 75/min, and respiration rate 12/min. Her high blood pressure is confirmed during a 2nd visit. Neurologic examination shows no abnormalities. Careful auscultation of the abdomen reveals bruits in both upper quadrants near the midline. The remainder of the physical exam is unremarkable. The results of a complete blood count (CBC), renal function panel, and urinalysis showed no abnormalities. Conventional angiography confirms bilateral disease involvement. To control this patient’s hypertension, it is most appropriate to recommend which of the following?
A. Percutaneous transluminal angioplasty (Correct Answer)
B. Dietary salt restriction
C. Long-term captopril
D. Surgical revascularization
E. Calorie restriction and weight loss
Explanation: ***Percutaneous transluminal angioplasty***
- The presence of **bilateral abdominal bruits** and **resistant hypertension** in a young woman strongly suggests **fibromuscular dysplasia** leading to renal artery stenosis.
- Percutaneous transluminal angioplasty (PTA) is the **definitive treatment** for fibromuscular dysplasia, by dilating the narrowed renal arteries and restoring blood flow.
*Dietary salt restriction*
- While salt restriction is a general recommendation for hypertension, it is **insufficient** to control severe hypertension caused by renovascular disease such as **fibromuscular dysplasia**.
- This approach does not address the **underlying anatomical obstruction** in the renal arteries.
*Long-term captopril*
- **Angiotensin-converting enzyme (ACE) inhibitors** like captopril are generally **contraindicated** or should be used with extreme caution in patients with **bilateral renal artery stenosis**.
- These drugs can paradoxically **worsen renal function** and even induce **acute kidney injury** by reducing glomerular filtration pressure due to efferent arteriolar vasodilation.
*Surgical revascularization*
- Surgical revascularization (bypass grafting) is a more **invasive procedure** typically reserved for **atherosclerotic renal artery stenosis** with significant occlusions or when PTA has failed.
- It is **less commonly indicated** for fibromuscular dysplasia, which usually responds well to less invasive angioplasty.
*Calorie restriction and weight loss*
- Calorie restriction and weight loss are lifestyle modifications that can help manage **primary (essential) hypertension**, particularly in overweight or obese individuals.
- However, they are **ineffective** in treating **secondary hypertension** caused by a structural renal artery issue like fibromuscular dysplasia.
Question 74: A 65-year-old woman presents to the clinic for a routine checkup. She has unintentionally lost 4.5 kg (9.9 lb) in the past month but denies any other complaints. Her pulse rate is 90/min, respiratory rate is 18/min, temperature is 37.0°C (98.6°F), and blood pressure is 150/70 mm Hg. An irregularly irregular rhythm is heard on auscultation of the heart. Neck examination shows a markedly enlarged thyroid with no lymphadenopathy or bruit. Laboratory tests show low serum thyroid-stimulating hormone level, high T4 level, absent thyroid-stimulating immunoglobulin, and absent anti-thyroid peroxidase antibody. Nuclear scintigraphy shows patchy uptake with multiple hot and cold areas. Which of the following is the most likely diagnosis?
A. Toxic multinodular goiter (Correct Answer)
B. Hashimoto’s thyroiditis
C. Graves’ disease
D. Subacute granulomatous thyroiditis
E. Toxic adenoma
Explanation: ***Toxic multinodular goiter***
- The patient's presentation with **unexplained weight loss**, **irregularly irregular rhythm** (suggesting atrial fibrillation), and an **enlarged thyroid** points towards hyperthyroidism.
- **Low TSH, high T4**, absent thyroid-stimulating immunoglobulin, and **patchy uptake with multiple hot and cold areas on scintigraphy** are all characteristic features of toxic multinodular goiter.
*Hashimoto’s thyroiditis*
- This is an **autoimmune condition** that typically causes **hypothyroidism** due to thyroid destruction, leading to high TSH and low thyroid hormone levels.
- It is characterized by the presence of **anti-thyroid peroxidase antibodies**, which are absent in this case.
*Graves’ disease*
- While it causes hyperthyroidism with **low TSH and high T4**, it is characterized by the presence of **thyroid-stimulating immunoglobulins** and **diffuse uptake on scintigraphy**.
- This patient has absent thyroid-stimulating immunoglobulins and patchy uptake, ruling out Graves' disease.
*Subacute granulomatous thyroiditis*
- This condition, often preceded by a **viral infection**, typically presents with **thyroid pain** and tenderness, which are absent in this case.
- Scintigraphy would show **decreased or absent iodine uptake** during the initial hyperthyroid phase, not patchy uptake.
*Toxic adenoma*
- A toxic adenoma would present with a **solitary hot nodule** on nuclear scintigraphy, which is a single area of increased uptake, unlike the multiple hot and cold areas seen in this patient.
- While it can cause hyperthyroidism, the scintigraphy findings are inconsistent with a single toxic adenoma.
Question 75: A 66-year old man comes to the physician because of fatigue for 6 months. He says that he wakes up every morning feeling tired. Most days of the week he feels sleepy during the day and often takes an afternoon nap for an hour. His wife says he snores in the middle of the night. He has a history of heart failure and atrial fibrillation. His medications include aspirin, atorvastatin, lisinopril, metoprolol, and warfarin. He drinks 1–2 glasses of wine daily with dinner; he does not smoke. He is 175 cm (5 ft 9 in) tall and weighs 96 kg (212 lb); BMI is 31.3 kg/m2. His blood pressure is 142/88 mm Hg, pulse is 98/min, and respirations are 22/min. Examination of the oral cavity shows a low-lying palate. Cardiac examination shows an irregularly irregular rhythm and no murmurs. The remainder of the examination shows no abnormalities. Which of the following is the most appropriate next step in management?
A. Echocardiography
B. Home sleep apnea testing
C. ENT evaluation
D. In-laboratory polysomnography (Correct Answer)
E. Overnight pulse oximetry
Explanation: ***In-laboratory polysomnography***
- The patient presents with classic symptoms of **obstructive sleep apnea (OSA)**, including chronic fatigue, daytime sleepiness, and snoring, along with risk factors such as **obesity (BMI 31.3)** and a **low-lying palate**. His medical history of **heart failure** and **atrial fibrillation** are also associated with OSA.
- While **portable home sleep apnea testing** can be used to diagnose OSA, in-laboratory polysomnography is indicated when there is a **strong suspicion of sleep apnea** and **comorbid conditions** (like heart failure and atrial fibrillation in this case) that might require more comprehensive monitoring of sleep stages, respiratory effort, and cardiac rhythm during sleep.
*Echocardiography*
- This patient has a history of heart failure and atrial fibrillation, for which an echocardiogram would typically be part of routine management, but there are no new acute cardiac symptoms or signs to suggest a need for immediate re-evaluation.
- Addressing the **sleep-related symptoms** that significantly impact his quality of life and potentially exacerbate his cardiac conditions takes precedence at this moment.
*ENT evaluation*
- An ENT evaluation might be considered later if **in-laboratory polysomnography** confirms severe OSA and surgical intervention, such as uvulopalatopharyngoplasty, is being considered.
- However, immediate ENT consultation is not the most appropriate first step in diagnosing or managing the sleep disorder.
*Home sleep apnea testing*
- While home sleep apnea testing (HSAT) is a convenient and cost-effective option for diagnosing OSA in patients with a high pretest probability and no significant comorbidities, it is **less comprehensive** than in-laboratory polysomnography.
- Given the patient's **comorbid heart failure and atrial fibrillation**, in-laboratory polysomnography is preferred to allow for more detailed physiological monitoring during sleep, including continuous EEG to determine sleep stages, which is crucial for distinguishing between central and obstructive events.
*Overnight pulse oximetry*
- **Overnight pulse oximetry** can screen for nocturnal hypoxemia but is **insufficient for diagnosing sleep apnea**.
- It does not provide information on sleep stages, respiratory effort, or arousals, which are critical for characterizing the type and severity of sleep-disordered breathing.
Question 76: A 73-year-old male is brought into the ED unconscious with cold, clammy skin. His blood pressure is 65 over palpable. There are no signs of blood loss. You recognize the patient is in acute shock and blood is drawn for investigation as resuscitation is initiated. Which of the following might you expect in your laboratory investigation for this patient?
A. Increased serum bicarbonate
B. Increased arterial pH
C. Decreased hemoglobin
D. Increased serum ketones
E. Increased blood lactate (Correct Answer)
Explanation: ***Increased blood lactate***
- In **shock**, inadequate tissue perfusion leads to **anaerobic metabolism**, which produces **lactic acid** as a byproduct.
- This accumulation of **lactate** is a key indicator of tissue hypoperfusion and is characteristic of various forms of shock.
*Increased serum bicarbonate*
- **Metabolic acidosis** is common in shock due to lactic acid accumulation, which would lead to a *decrease* in serum bicarbonate as the body tries to **buffer the acid**.
- An increased bicarbonate level would suggest **metabolic alkalosis**, which is not expected in this context.
*Increased arterial pH*
- The elevated lactic acid levels from **anaerobic metabolism** in shock cause **metabolic acidosis**, leading to a *decreased* arterial pH.
- An increased pH would indicate **alkalosis**, which is contrary to the expected physiological response in shock.
*Decreased hemoglobin*
- While a **decreased hemoglobin** could be a cause of shock (hemorrhagic shock), the question explicitly states there are **no signs of blood loss**.
- Additionally, other forms of shock (e.g., cardiogenic, septic) would not necessarily present with decreased hemoglobin.
*Increased serum ketones*
- **Ketone bodies** are elevated in conditions involving increased **fat metabolism** due to **insulin deficiency** (e.g., diabetic ketoacidosis) or prolonged starvation.
- While a patient in shock might have metabolic derangements, significant ketosis is not a primary or direct result of the **hypoperfusion** itself in the absence of other underlying conditions.
Question 77: A 14-year-old boy is brought to the emergency department from school after falling in gym class. He was unable to stand after the accident and has a painful and swollen knee. On presentation he says that he has never had an incident like this before; however, he does suffer from hard to control nosebleeds and prolonged bleeding after minor cuts. Based on his presentation a panel of bleeding tests is obtained with the following results:
Bleeding time: Prolonged
Prothrombin time: Normal
Partial thromboplastin time: Prolonged
Which of the following describes the function of the component that is defective in the most likely cause of this patient's symptoms?
A. Binds to a nucleotide derivative
B. Binds to fibrinogen
C. Binds to subendothelial collagen (Correct Answer)
D. It is a cofactor for an epoxide reductase
E. Catalyzes the conversion of factor X
Explanation: ***Binds to subendothelial collagen***
- The patient's history of **nosebleeds**, **prolonged bleeding**, and a knee injury suggests a **primary hemostasis** defect. The lab results (prolonged bleeding time, normal PT, prolonged PTT) point to **von Willebrand disease** (vWD).
- The most important function of **von Willebrand factor** (vWF), which is deficient or dysfunctional in vWD, is to mediate platelet adhesion to the **subendothelial collagen** at sites of vascular injury.
*Binds to a nucleotide derivative*
- This option refers to the function of **P2Y12 receptors** on platelets, which bind to ADP (a nucleotide derivative) to promote platelet aggregation.
- While important for platelet function, this is not the primary defect in von Willebrand disease, which is an issue with **platelet adhesion**.
*Binds to fibrinogen*
- **Glycoprotein IIb/IIIa receptors** on platelets bind to **fibrinogen** to mediate platelet aggregation and form a platelet plug.
- This is a secondary step in hemostasis, and while affected by vWF's indirect role in stabilizing FVIII, it's not the direct primary defect.
*It is a cofactor for an epoxide reductase*
- This describes the role of **Vitamin K** in the carboxylation of clotting factors; specifically, its role as a cofactor for **gamma-glutamyl carboxylase**, which is then reduced by **epoxide reductase**.
- Deficiencies in Vitamin K activity affect the **extrinsic** and **common pathways** (factors II, VII, IX, X), which would typically present with a **prolonged PT** in addition to PTT, unlike this patient.
*Catalyzes the conversion of factor X*
- This describes the function of **Factor IXa** (in complex with Factor VIIIa) and **Factor VIIa** (with Tissue Factor), which activate Factor X to Factor Xa.
- While vWF stabilizes **Factor VIII**, leading to prolonged PTT, the direct catalytic conversion of Factor X is not the primary function of vWF itself.
Question 78: A 66-year-old man is brought to the emergency department because of fever, chills, and altered mental status for 3 days. According to his daughter, he has had a productive cough during this period. He has type 2 diabetes, hypertension, hypercholesterolemia, peripheral neuropathic pain, and a history of deep vein thromboses. Current medications include insulin, lisinopril, atorvastatin, warfarin, and carbamazepine. He is oriented only to self. His temperature is 39.3°C (102.7°F), pulse is 110/min, respirations are 26/min, and blood pressure is 86/50 mm Hg. Physical examination shows ecchymoses on both lower extremities. Crackles are heard at the right lung base. Laboratory studies show:
Hemoglobin 11.1 g/dL
Leukocyte count 18,000/mm3
Platelet count 45,000/mm3
Prothrombin time 45 sec
Partial thromboplastin time 75 sec
Serum
Na+ 135 mEq/L
K+ 5.4 mEq/L
Cl- 98 mEq/L
Urea nitrogen 46 mg/dL
Glucose 222 mg/dL
Creatinine 3.3 mg/dL
Which of the following is the most likely cause of this patient's ecchymoses?
A. Adverse effect of warfarin
B. Immune thrombocytopenic purpura
C. Hemolytic uremic syndrome
D. Disseminated intravascular coagulation (Correct Answer)
E. Thrombotic thrombocytopenic purpura
Explanation: ***Disseminated intravascular coagulation***
- The patient presents with **sepsis** (fever, altered mental status, productive cough, crackles, hypotension, leukocytosis), **thrombocytopenia** (platelet count 45,000/mm3), and **prolonged PT and PTT** (45 sec and 75 sec, respectively). These findings, in the setting of severe infection, are highly suggestive of **DIC**.
- **Ecchymoses** are a common manifestation of DIC due to widespread microthrombi consuming clotting factors and platelets, leading to subsequent bleeding.
*Adverse effect of warfarin*
- While the patient is on warfarin, his **severe thrombocytopenia** (45,000/mm3) and **markedly prolonged PTT** are not typical findings for isolated warfarin overdose; warfarin primarily prolongs PT and sometimes PTT, but usually doesn't cause such a severe drop in platelet count.
- Furthermore, isolated warfarin toxicity would not explain the patient's profound **sepsis** and multi-organ dysfunction.
*Immune thrombocytopenic purpura*
- ITP is characterized by **isolated thrombocytopenia** without other coagulation abnormalities or systemic illness like sepsis.
- This patient has signs of **severe infection**, coagulation factor consumption (prolonged PT/PTT), and renal dysfunction, which are not features of ITP.
*Hemolytic uremic syndrome*
- HUS involves **microangiopathic hemolytic anemia** (MAHA), **thrombocytopenia**, and **acute kidney injury** (AKI), often preceded by a diarrheal illness.
- While this patient has thrombocytopenia and AKI, there is no mention of hemolytic anemia (e.g., schistocytes, elevated LDH, decreased haptoglobin), and the prolonged PT/PTT are not characteristic of HUS alone.
*Thrombotic thrombocytopenic purpura*
- TTP classically presents with the **pentad** of fever, neurological symptoms, renal dysfunction, thrombocytopenia, and microangiopathic hemolytic anemia (MAHA).
- Similar to HUS, TTP is not associated with prolonged PT and PTT, which are prominent features in this patient and point towards a consumptive coagulopathy like DIC.
Question 79: A 27-year-old man is brought to the emergency department with his family because of abdominal pain, excessive urination and drowsiness since the day before. He has had type 1 diabetes mellitus for 2 years. He ran out of insulin 2 days ago. His vital signs at admission include a temperature of 36.8°C (98.24°F), a blood pressure of 102/69 mmHg, and a pulse of 121/min. On physical examination, he is lethargic and his breathing is rapid and deep. There is a mild generalized abdominal tenderness without rebound tenderness or guarding. His serum glucose is 480 mg/dL. The patient is admitted to the intensive care unit and management is started. Which of the following is considered a resolution criterion for this patient's condition?
A. Anion gap < 10 (Correct Answer)
B. Bicarbonate < 10 mEq/L
C. Increased blood urea nitrogen
D. Disappearance of serum acetone
E. Hyperkalemia
Explanation: ***Anion gap < 10***
- Resolution of **diabetic ketoacidosis (DKA)** is indicated by the closure of the **anion gap**, typically defined as an anion gap less than 10-12 mEq/L, signifying the correction of metabolic acidosis.
- This criterion, along with serum bicarbonate ≥ 15 mEq/L and blood pH > 7.3, confirms that the excess ketoacids have been cleared.
*Bicarbonate < 10 mEq/L*
- A bicarbonate level less than 10 mEq/L indicates severe **metabolic acidosis**, which is characteristic of DKA, not a sign of its resolution.
- As DKA resolves, **bicarbonate levels should increase** towards the normal range (typically ≥ 15 mEq/L for resolution).
*Increased blood urea nitrogen*
- **Increased BUN** reflects changes in kidney function, often due to dehydration in DKA, but it is not a direct measure of DKA resolution.
- While hydration therapy will improve renal function, BUN levels may not normalize immediately and their elevation does not directly track the resolution of the **ketoacidotic state**.
*Disappearance of serum acetone*
- While the disappearance of serum acetone (a **ketone body**) indicates a reduction in ketosis, it is not the primary or sole resolution criterion.
- **Beta-hydroxybutyrate** is the predominant ketone in DKA, and its levels returning to normal are more indicative; however, blood pH and anion gap are more robust indicators for overall resolution.
*Hyperkalemia*
- **Hyperkalemia** can occur in DKA due to acidosis, but paradoxically, total body **potassium is deficient**.
- As insulin therapy is initiated and acidosis corrects, potassium shifts back into cells, often leading to **hypokalemia**, necessitating careful potassium monitoring and replacement; it is not a resolution criterion but a potential complication of treatment or the underlying condition.
Question 80: A 25-year-old man comes to the physician because of a severe headache for 1 hour. Every day of the past week, he has experienced 3–4 episodes of severe pain over his left forehead. Each episode lasts around 30–45 minutes, and he reports pacing around restlessly during these episodes. He has been using acetaminophen for these episodes, but it has provided only minimal relief. He works as a financial analyst and says his job is very stressful. He had experienced similar symptoms 4 months ago but did not seek treatment at that time. He has no history of serious illness and takes no other medications. He has smoked one pack of cigarettes daily for 7 years. He appears anxious. Vital signs are within normal limits. There is conjunctival injection and tearing of the left eye. The remainder of the physical examination is unremarkable. Which of the following measures is most likely to provide acute relief of this patient's headaches?
A. Oxygen therapy (Correct Answer)
B. Naproxen
C. Oxycodone
D. Amitriptyline
E. Carbamazepine
Explanation: ***Oxygen therapy***
- This patient's symptoms (unilateral severe headache, conjunctival injection, tearing, restlessness, short duration, and recurrent episodes) are characteristic of **cluster headaches**.
- **High-flow oxygen (100% at 12-15 L/min)** delivered via a non-rebreather mask is a highly effective and safe acute treatment for cluster headaches, often providing relief within 15-20 minutes.
*Naproxen*
- **Naproxen**, an NSAID, is a common acute treatment for **mild to moderate tension-type headaches** or in conjunction with other abortive medications for migraine.
- It is generally **ineffective** for the severe pain and distinct autonomic features of cluster headaches.
*Oxycodone*
- **Opioids like oxycodone** are not recommended for acute treatment of cluster headaches due to the risk of **medication overuse headache**, dependence, and their lack of specific efficacy for this condition.
- They tend to be less effective than specific cluster headache treatments and can **aggravate the condition** with long-term use.
*Amitriptyline*
- **Amitriptyline** is a tricyclic antidepressant primarily used for the **prophylactic treatment** of **chronic tension-type headaches or migraines**.
- It is **not effective** for the acute termination of a cluster headache attack.
*Carbamazepine*
- **Carbamazepine** is an anticonvulsant primarily used to treat **trigeminal neuralgia** due to its efficacy in neuropathic pain.
- While sometimes used second-line in other headache disorders, it is **not a first-line acute treatment** for cluster headaches and its effectiveness in this context is limited.
