Infectious diseases (sepsis, endocarditis)

Infectious diseases (sepsis, endocarditis) 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

Infectious diseases (sepsis, endocarditis) 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.

Infectious diseases (sepsis, endocarditis) US Medical PG Question 2: Blood cultures are sent to the laboratory and empiric treatment with intravenous vancomycin is started. Blood cultures grow gram-negative bacilli identified as Cardiobacterium hominis. Which of the following is the most appropriate next step in management?

• A. Switch to intravenous gentamicin
• B. Switch to intravenous ampicillin
• C. Switch to intravenous ceftriaxone (Correct Answer)
• D. Switch to intravenous cefazolin
• E. Add intravenous rifampin

Infectious diseases (sepsis, endocarditis) Explanation: ***Switch to intravenous ceftriaxone*** - **Cardiobacterium hominis** is part of the **HACEK group** of bacteria, which are known for causing **endocarditis**. - These organisms are typically susceptible to **beta-lactam antibiotics**, with **third-generation cephalosporins** like ceftriaxone being the drug of choice due to their excellent activity and good penetration. *Switch to intravenous gentamicin* - While **aminoglycosides** like gentamicin can be used in combination regimens for serious infections, they are generally **not monotherapy** for HACEK endocarditis and are associated with **nephrotoxicity** and **ototoxicity**. - The primary treatment for HACEK endocarditis is a **beta-lactam antibiotic**, not an aminoglycoside alone. *Switch to intravenous ampicillin* - **Ampicillin** is a beta-lactam, but it may not consistently provide optimal coverage for all HACEK organisms, and some strains may have reduced susceptibility. - **Third-generation cephalosporins** are preferred due to their broader and more consistent activity against this group. *Switch to intravenous cefazolin* - **Cefazolin** is a first-generation cephalosporin and typically has **limited activity** against gram-negative bacilli, especially those like Cardiobacterium hominis which require broader-spectrum beta-lactams. - Its spectrum of activity is primarily against **gram-positive bacteria** and some **gram-negative cocci**. *Add intravenous rifampin* - **Rifampin** is primarily used for **mycobacterial infections** and in combination regimens for specific bacterial infections (e.g., bone and joint infections, prosthetic device infections) often due to resistant staphylococci. - It is **not a first-line agent** for Cardiobacterium hominis infections and there's no indication for its use here with an organism susceptible to ceftriaxone.

Infectious diseases (sepsis, endocarditis) US Medical PG Question 3: Three days after admission to the hospital following a motor vehicle accident, a 45-year-old woman develops a fever. A central venous catheter was placed on the day of admission for treatment of severe hypotension. Her temperature is 39.2°C (102.5°F). Examination shows erythema surrounding the catheter insertion site at the right internal jugular vein. Blood cultures show gram-positive, catalase-positive cocci that have a high minimum inhibitory concentration when exposed to novobiocin. Which of the following is the most appropriate pharmacotherapy?

• A. Clarithromycin
• B. Vancomycin (Correct Answer)
• C. Metronidazole
• D. Penicillin G
• E. Polymyxin B

Infectious diseases (sepsis, endocarditis) Explanation: ***Vancomycin*** - The description of **gram-positive, catalase-positive cocci** that are **novobiocin-resistant** (high MIC) strongly points to **Staphylococcus epidermidis** or other coagulase-negative staphylococci. *S. epidermidis* is the most common cause of **catheter-related bloodstream infections** and is often **methicillin-resistant**, making **vancomycin** the drug of choice. - The presence of erythema at the catheter site and fever in a patient with a central venous catheter indicates a **central line-associated bloodstream infection (CLABSI)**, for which empiric coverage with vancomycin is standard until sensitivities are known. - The novobiocin resistance test helps differentiate *S. epidermidis* (resistant) from *S. saprophyticus* (sensitive). *Clarithromycin* - **Clarithromycin** is a macrolide antibiotic primarily used for respiratory tract infections and *Mycobacterium avium complex*. - It is **not effective** against methicillin-resistant staphylococci and would not be appropriate for a suspected CLABSI. *Metronidazole* - **Metronidazole** is an antibiotic mainly used for **anaerobic bacterial infections** and certain parasitic infections. - It has **no activity** against gram-positive cocci like staphylococci. *Penicillin G* - **Penicillin G** is a narrow-spectrum penicillin effective against some gram-positive cocci, like **Streptococcus pyogenes**. - However, virtually all staphylococci, especially those causing hospital-acquired infections, are **resistant to penicillin G** due to beta-lactamase (penicillinase) production. *Polymyxin B* - **Polymyxin B** is an antibiotic primarily effective against **gram-negative bacteria**, particularly those with multi-drug resistance such as **Pseudomonas aeruginosa** and **Acinetobacter baumannii**. - It has **no significant activity** against gram-positive cocci like staphylococci.

Infectious diseases (sepsis, endocarditis) US Medical PG Question 4: A 46-year-old male was found unconscious in the field and brought to the emergency department by EMS. The patient was intubated in transit and given a 2 liter bolus of normal saline. On arrival, the patient's blood pressure is 80/60 mmHg and temperature is 37.5°C. Jugular veins are flat and capillary refill time is 4 seconds. Vascular parameters are measured and are as follows: Cardiac index - Low Pulmonary capillary wedge pressure (PCWP) - Low Systemic vascular resistance - High Which of the following is the most likely diagnosis?

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

Infectious diseases (sepsis, endocarditis) Explanation: ***Hypovolemic shock*** - The patient presents with **hypotension**, **flat jugular veins**, **prolonged capillary refill**, and a **low cardiac index** and **low pulmonary capillary wedge pressure (PCWP)**, all indicative of inadequate intravascular volume. - The **high systemic vascular resistance** is a compensatory mechanism to maintain blood pressure in the setting of decreased circulating volume. *Septic shock* - Septic shock typically presents with **vasodilation**, leading to a **low systemic vascular resistance**, which contradicts the findings in this patient. - While patients can be hypotensive, the vascular parameters, especially SVR, do not align with septic shock. *Anaphylactic shock* - This type of shock is characterized by widespread **vasodilation** and increased capillary permeability, leading to a **low systemic vascular resistance** and often significant **edema** or **urticaria**, none of which are suggested here. - While it can cause hypotension and low PCWP due to fluid shifts, the high SVR makes it less likely. *Cardiogenic shock* - Cardiogenic shock is characterized by **pump failure**, leading to a **low cardiac index** but a **high PCWP** due to fluid backup in the pulmonary circulation. - This directly contrasts the patient's low PCWP. *Neurogenic shock* - Neurogenic shock involves a loss of **sympathetic tone**, resulting in widespread **vasodilation** and a **low systemic vascular resistance**, often accompanied by **bradycardia**. - The high SVR in this patient rules out neurogenic shock.

Infectious diseases (sepsis, endocarditis) US Medical PG Question 5: A 65-year-old man presents with low-grade fever and malaise for the last 4 months. He also says he has lost 9 kg (20 lb) during this period and suffers from extreme fatigue. Past medical history is significant for a mitral valve replacement 5 years ago. His temperature is 38.1°C (100.6°F), respirations are 22/min, pulse is 102/min, and blood pressure is 138/78 mm Hg. On physical examination, there is a new onset 2/6 holosystolic murmur loudest in the apical area of the precordium. Which of the following organisms is the most likely cause of this patient’s condition?

• A. Enterococcus (Correct Answer)
• B. Candida albicans
• C. Coagulase-negative Staphylococcus spp.
• D. Escherichia coli
• E. Pseudomonas aeruginosa

Infectious diseases (sepsis, endocarditis) Explanation: ***Enterococcus*** - This patient has **late prosthetic valve endocarditis (PVE)**, occurring **5 years after mitral valve replacement**. - Late PVE (>1 year post-surgery) is most commonly caused by **viridans streptococci** and ***Staphylococcus aureus***, followed by **Enterococcus species**. - Among the given options, ***Enterococcus*** is the most common cause, particularly in **elderly patients**. - The **subacute presentation** with **4 months of low-grade fever, malaise, weight loss**, and **new-onset murmur** is consistent with enterococcal endocarditis. - Enterococcus is a common cause of healthcare-associated endocarditis and has increased prevalence in patients with prosthetic valves. *Coagulase-negative Staphylococcus spp.* - Coagulase-negative staphylococci (e.g., *S. epidermidis*) are the **most common cause of early PVE** (within the first year after surgery). - At **5 years post-surgery**, this represents **late PVE**, where coagulase-negative staph is much less common than streptococci, *S. aureus*, and enterococci. - While it can occur in late PVE, it is not the most likely organism in this timeframe. *Escherichia coli* - *E. coli* is an uncommon cause of endocarditis, typically associated with underlying gastrointestinal or urinary tract sources. - It generally presents **acutely** rather than with the subacute 4-month course seen here. - Not a typical cause of prosthetic valve endocarditis. *Candida albicans* - Fungal endocarditis is rare and typically seen in **immunocompromised patients, IV drug users**, or those with **prolonged ICU stays** with indwelling catheters. - While *Candida* can cause PVE, it is much less common than bacterial causes in this clinical context. *Pseudomonas aeruginosa* - *Pseudomonas* endocarditis typically occurs in **IV drug users** and commonly affects the **tricuspid valve** (right-sided). - Usually presents as an **acute infection** rather than the subacute presentation here. - Not a common cause of late prosthetic valve endocarditis in non-IVDU patients.

Infectious diseases (sepsis, endocarditis) US Medical PG Question 6: A 28-year-old male presents to his primary care physician with complaints of intermittent abdominal pain and alternating bouts of constipation and diarrhea. His medical chart is not significant for any past medical problems or prior surgeries. He is not prescribed any current medications. Which of the following questions would be the most useful next question in eliciting further history from this patient?

• A. "Does the diarrhea typically precede the constipation, or vice-versa?"
• B. "Is the diarrhea foul-smelling?"
• C. "Please rate your abdominal pain on a scale of 1-10, with 10 being the worst pain of your life"
• D. "Are the symptoms worse in the morning or at night?"
• E. "Can you tell me more about the symptoms you have been experiencing?" (Correct Answer)

Infectious diseases (sepsis, endocarditis) Explanation: ***Can you tell me more about the symptoms you have been experiencing?*** - This **open-ended question** encourages the patient to provide a **comprehensive narrative** of their symptoms, including details about onset, frequency, duration, alleviating/aggravating factors, and associated symptoms, which is crucial for diagnosis. - In a patient presenting with vague, intermittent symptoms like alternating constipation and diarrhea, allowing them to elaborate freely can reveal important clues that might not be captured by more targeted questions. *Does the diarrhea typically precede the constipation, or vice-versa?* - While knowing the sequence of symptoms can be helpful in understanding the **pattern of bowel dysfunction**, it is a very specific question that might overlook other important aspects of the patient's experience. - It prematurely narrows the focus without first obtaining a broad understanding of the patient's overall symptomatic picture. *Is the diarrhea foul-smelling?* - Foul-smelling diarrhea can indicate **malabsorption** or **bacterial overgrowth**, which are important to consider in some gastrointestinal conditions. - However, this is a **specific symptom inquiry** that should follow a more general exploration of the patient's symptoms, as it may not be relevant if other crucial details are missed. *Please rate your abdominal pain on a scale of 1-10, with 10 being the worst pain of your life* - Quantifying pain intensity is useful for assessing the **severity of discomfort** and monitoring changes over time. - However, for a patient with intermittent rather than acute, severe pain, understanding the **character, location, and triggers** of the pain is often more diagnostically valuable than just a numerical rating initially. *Are the symptoms worse in the morning or at night?* - Diurnal variation can be relevant in certain conditions, such as inflammatory bowel diseases where nocturnal symptoms might be more concerning, or functional disorders whose symptoms might be stress-related. - This is another **specific question** that should come after gathering a more complete initial picture of the patient's symptoms to ensure no key information is overlooked.

Infectious diseases (sepsis, endocarditis) US Medical PG Question 7: A 50-year-old man with a history of stage 4 kidney disease was admitted to the hospital for an elective hemicolectomy. His past medical history is significant for severe diverticulitis. After the procedure he becomes septic and was placed on broad spectrum antibiotics. On morning rounds, he appear weak and complains of fatigue and nausea. His words are soft and he has difficulty answering questions. His temperature is 38.9°C (102.1°F), heart rate is 110/min, respiratory rate is 15/min, blood pressure 90/65 mm Hg, and saturation is 89% on room air. On physical exam, his mental status appears altered. He has a bruise on his left arm that spontaneously appeared overnight. His cardiac exam is positive for a weak friction rub. Blood specimens are collected and sent for evaluation. An ECG is performed (see image). What therapy will this patient most likely receive next?

• A. Send the patient for hemodialysis (Correct Answer)
• B. Perform a STAT pericardiocentesis
• C. Prepare the patient for renal transplant
• D. Treat the patient with aspirin
• E. Treat the patient with cyclophosphamide and prednisone

Infectious diseases (sepsis, endocarditis) Explanation: ***Send the patient for hemodialysis*** - This patient presents with symptoms of **uremic encephalopathy** and **uremic pericarditis** in the context of **stage 4 kidney disease**. The altered mental status, weakness, fatigue, nausea, and the development of a bruise (which could indicate uremic coagulopathy) are suggestive of severe uremia. The ECG shows widespread **ST elevation and PR depression**, particularly noticeable in leads like II, V2-V6, which is a classic finding for pericarditis. The **weak friction rub** confirms this clinical suspicion. Hemodialysis is crucial to rapidly remove uremic toxins and resolve both uremic encephalopathy and pericarditis. - The ECG findings, including diffuse **ST elevation** with **PR depression**, are characteristic of **pericarditis**. In a patient with end-stage renal disease, **uremia** is a common cause of pericarditis, which can be life-threatening if not promptly treated with dialysis. *Perform a STAT pericardiocentesis* - While the patient has pericarditis, there are no immediate signs of **cardiac tamponade**, such as muffled heart sounds, jugular venous distension, or pulsus paradoxus, that would necessitate an emergency pericardiocentesis. - The primary treatment for **uremic pericarditis** is typically **hemodialysis** to resolve the underlying uremic state, not direct fluid removal unless tamponade is present. *Prepare the patient for renal transplant* - **Renal transplant** is a long-term solution for end-stage renal disease, but it is not an acute intervention for immediate life-threatening uremic complications like uremic pericarditis and encephalopathy. - The patient needs urgent stabilization and treatment of his current acute medical issues before transplant consideration. *Treat the patient with aspirin* - While aspirin can be used for some forms of pericarditis, it is generally **contraindicated** in patients with **uremic pericarditis** due to the increased risk of **gastric bleeding** and potential exacerbation of uremic coagulopathy. - The primary treatment for uremic pericarditis is **dialysis**, not anti-inflammatory medications, as the inflammation is driven by uremic toxins. *Treat the patient with cyclophosphamide and prednisone* - **Immunosuppressants** like cyclophosphamide and prednisone are used for autoimmune or inflammatory conditions causing pericarditis, such as systemic lupus erythematosus. - This patient's pericarditis is clearly linked to **uremia** from kidney disease, not an autoimmune condition, making immunosuppressive therapy inappropriate and potentially harmful.

Infectious diseases (sepsis, endocarditis) US Medical PG Question 8: Five days after admission into the ICU for drug-induced acute kidney injury, a 27-year-old woman develops fever. She is currently on a ventilator and sedatives. Hemodialysis is performed via a catheter placed in the right internal jugular vein. Feeding is via a nasogastric tube. An indwelling urinary catheter shows minimum output. Her blood pressure is 85/45 mm Hg, the pulse is 112/min, the respirations are 32/min, and the temperature is 39.6°C (103.3°F). The examination of the central catheter shows erythema around the insertion site with no discharge. Lung auscultation shows rhonchi. Cardiac examination shows no new findings. A chest CT scan shows bilateral pleural effusions with no lung infiltration. Empirical antibiotic therapy is initiated. Blood cultures obtained from peripheral blood and the catheter tip show S. aureus with a similar antibiogram. Urinary culture obtained from the indwelling catheter shows polymicrobial growth. Which of the following best explains this patient’s recent findings?

• A. Catheter-associated urinary tract infection
• B. Central catheter-related bacteremia (Correct Answer)
• C. Endocarditis
• D. Ventilator-associated pneumonia
• E. Naso-gastric tube sinusitis

Infectious diseases (sepsis, endocarditis) Explanation: ***Central catheter-related bacteremia*** - The presence of **erythema at the catheter insertion site** and the isolation of **_S. aureus_ with a similar antibiogram from both peripheral blood and the catheter tip** are highly indicative of a catheter-related bloodstream infection. - This type of infection is common in critically ill patients with central venous catheters due to the direct access provided for bacteria to enter the bloodstream. *Catheter-associated urinary tract infection* - While a **polymicrobial growth** in the urinary culture suggests a urinary tract infection, the isolation of **_S. aureus_ in blood cultures** with signs of local catheter infection points away from the urinary tract as the primary source of bacteremia. - The patient has an **indwelling urinary catheter**, which is a risk factor for UTIs, but the systemic infection with _S. aureus_ is better explained by the central line. *Endocarditis* - Although **_S. aureus_ bacteremia** can lead to endocarditis, the case states that the **cardiac examination shows no new findings**, making endocarditis less likely as the primary explanation for the acute deterioration without other supporting evidence like a new murmur or imaging findings. - Endocarditis is a potential complication of bacteremia, not typically the initial source, especially with a clear source like a central line. *Ventilator-associated pneumonia* - Pulmonary symptoms like **rhonchi** and **bilateral pleural effusions** are present, but the **lack of lung infiltration on CT** and the **isolation of _S. aureus_ from blood and catheter tip** (not respiratory samples) make VAP unlikely to be the primary cause of this systemic infection. - The patient is also on a ventilator, which is a risk factor for VAP, but the microbiologic and imaging evidence does not fully support it as the main diagnosis. *Naso-gastric tube sinusitis* - While nasogastric tubes can cause sinusitis, which could manifest with fever, it is less likely to result in **_S. aureus_ bacteremia with a positive catheter tip culture**. - Sinusitis would explain fever, but not the specific microbiological findings of _S. aureus_ in blood and catheter tip, nor the local erythema at the catheter site.

Infectious diseases (sepsis, endocarditis) US Medical PG Question 9: A 65-year-old man presents to the emergency department with a fever and weakness. He states his symptoms started yesterday and have been gradually worsening. The patient has a past medical history of obesity, diabetes, alcohol abuse, as well as a 30 pack-year smoking history. He lives in a nursing home and has presented multiple times in the past for ulcers and delirium. His temperature is 103°F (39.4°C), blood pressure is 122/88 mmHg, pulse is 129/min, respirations are 24/min, and oxygen saturation is 99% on room air. Physical exam is notable for a murmur. The patient is started on vancomycin and piperacillin-tazobactam and is admitted to the medicine floor. During his hospital stay, blood cultures grow Streptococcus bovis and his antibiotics are appropriately altered. A transesophageal echocardiograph is within normal limits. The patient’s fever decreases and his symptoms improve. Which of the following is also necessary in this patient?

• A. Addiction medicine referral
• B. Colonoscopy (Correct Answer)
• C. Social work consult for elder abuse
• D. Repeat blood cultures for contamination concern
• E. Replace the patient’s central line and repeat echocardiography

Infectious diseases (sepsis, endocarditis) Explanation: ***Colonoscopy*** - The isolation of **_Streptococcus bovis_** (now often referred to as _Streptococcus gallolyticus_) from blood cultures is highly associated with **colorectal neoplasms** or other gastrointestinal pathologies. - A comprehensive workup, including a **colonoscopy**, is crucial to identify the underlying source of bacteremia and screen for malignancy. *Addiction medicine referral* - While the patient has a history of **alcohol abuse**, there is no indication that his current presentation or the discovery of _Streptococcus bovis_ necessitates an immediate addiction medicine referral as the primary next step from an acute management perspective. - Addiction management is an important long-term consideration but not the most pressing diagnostic need. *Social work consult for elder abuse* - The patient lives in a **nursing home** and has a history of delirium and frequent hospitalizations for ulcers, which can be concerning. However, there are no specific signs or symptoms presented in this vignette that directly suggest elder abuse as the reason for his current _S. bovis_ bacteremia, making it a less immediate priority compared to diagnosing the source of infection. - While a general social work assessment might be beneficial for a vulnerable patient in a nursing home, it is not the most necessary intervention based on the microbiological finding. *Repeat blood cultures for contamination concern* - The question states that **_Streptococcus bovis_** blood cultures "grew" and antibiotics were "appropriately altered," suggesting a confirmed infection rather than contamination. - Furthermore, _S. bovis_ is a known pathogen with specific associations and is not typically considered a common contaminant in the same vein as coagulase-negative staphylococci. *Replace the patient’s central line and repeat echocardiography* - The patient's **transesophageal echocardiogram (TEE) was normal**, ruling out endocarditis as the source of bacteremia in this case. - There is no mention of a central line, and even if there were, the normal TEE and the specific pathogen (_S. bovis_) point towards a gastrointestinal source.

Infectious diseases (sepsis, endocarditis) US Medical PG Question 10: A 71-year-old man presents to the emergency department with severe substernal chest pain. An initial EKG demonstrates ST elevation in leads V2, V3, V4, and V5 with reciprocal changes. The patient is started on aspirin and heparin and is transferred to the cardiac catheterization lab. The patient recovers over the next several days. On the floor, the patient complains of feeling very fatigued and feels too weak to ambulate even with the assistance of physical therapy. Chest radiography reveals an enlarged cardiac silhouette with signs of fluid bilaterally in the lung bases. His temperature is 98.4°F (36.9°C), blood pressure is 85/50 mmHg, pulse is 110/min, respirations are 13/min, and oxygen saturation is 97% on room air. Which of the following would be expected to be seen in this patient?

• A. Decreased systemic vascular resistance
• B. Increased venous oxygen content
• C. Increased ejection fraction
• D. Decreased tissue oxygen extraction
• E. Increased pulmonary capillary wedge pressure (Correct Answer)

Infectious diseases (sepsis, endocarditis) Explanation: ***Increased pulmonary capillary wedge pressure*** - The patient's symptoms of **fatigue**, **weakness**, **hypotension**, **tachycardia**, and **pulmonary congestion** (enlarged cardiac silhouette, bilateral pleural effusions) after a significant myocardial infarction are highly suggestive of **cardiogenic shock**. - In cardiogenic shock, the heart's pumping ability is severely compromised, leading to **increased end-diastolic filling pressures** in the left ventricle, which is reflected as an elevated **pulmonary capillary wedge pressure (PCWP)**. *Decreased systemic vascular resistance* - **Decreased systemic vascular resistance (SVR)** is a hallmark of **distributive shock**, such as septic shock, where widespread vasodilation occurs. - In **cardiogenic shock**, the body typically tries to compensate for reduced cardiac output by **increasing SVR** to maintain blood pressure, although this compensation may be overwhelmed, leading to hypotension. *Increased venous oxygen content* - **Increased mixed venous oxygen saturation (SvO2)** or **venous oxygen content** is seen when tissues are not adequately extracting oxygen, either due to shunt physiology or when oxygen delivery far exceeds demand. - In **cardiogenic shock**, tissue oxygen demand often exceeds delivery due to severely impaired cardiac output, leading to **increased oxygen extraction** by tissues and thus **decreased venous oxygen content**. *Increased ejection fraction* - The patient experienced a **large myocardial infarction (ST elevation in V2-V5)**, indicating substantial damage to the left ventricle. - This damage would severely impair the heart's pumping function, leading to a **decreased ejection fraction**, which is characteristic of **cardiogenic shock**. *Decreased tissue oxygen extraction* - **Decreased tissue oxygen extraction** would imply that tissues are not properly utilizing the delivered oxygen, or that oxygen delivery is so high that tissues don't need to extract as much. - In **cardiogenic shock**, cardiac output is severely reduced, leading to **inadequate oxygen delivery** to tissues, forcing them to **maximally extract oxygen** from the blood to meet metabolic demands.

Infectious diseases (sepsis, endocarditis) Flashcard 1 of 10

Question: How does cardiac output change during distributive shock due to sepsis and anaphylaxis?_____

Answer: Increased

Infectious diseases (sepsis, endocarditis) Flashcard 2 of 10

Question: Hypotension and distended neck veins + clear lungs = _____ infarction

Answer: right ventricular

Extra Information:  https://onlinemeded.org/spa/cardiology/coronary-artery-disease/acquire?ref=anki 

Infectious diseases (sepsis, endocarditis) Flashcard 3 of 10

Question: What kidney complication may be associated with bacterial endocarditis?_____

Answer: Glomerulonephritis

Infectious diseases (sepsis, endocarditis) Flashcard 4 of 10

Question: _____ shock may be caused by acute MI, HF, valvular dysfunction, and arrhythmia (pump failure)

Answer: Cardiogenic

Infectious diseases (sepsis, endocarditis) Flashcard 5 of 10

Question: What is the treatment of culture-negative endocarditis caused by Coxiella?_____

Answer: Doxycycline (along with hydroxychloroquine)

Infectious diseases (sepsis, endocarditis) Flashcard 6 of 10

Question: One symptom associated with bacterial endocarditis is _____, which occurs as blood flows over vegetations on the heart valve

Answer: murmur

Infectious diseases (sepsis, endocarditis) Flashcard 7 of 10

Question: _____ shock may be caused by acute MI, HF, valvular dysfunction, and arrhythmia (pump failure)

Answer: Cardiogenic

Extra Information:  Watch associated Bootcamp video [https://app.bootcamp.com/med-school/cardiology/videos/shock?index=4] https://onlinemeded.org/spa/surgery-trauma/shock/acquire?ref=anki 

Infectious diseases (sepsis, endocarditis) Flashcard 8 of 10

Question: Pneumocyctis pneumonia

Answer:

Extra Information: diffuse bilateral infiltrates on CXR

Infectious diseases (sepsis, endocarditis) Flashcard 9 of 10

Question: Extrapulmonary tuberculosis can affect the _____, _____, _____, _____, and _____.

Answer: CNS

Infectious diseases (sepsis, endocarditis) Flashcard 10 of 10

Question: prostatitis

Answer: acute - bacterial infection chronic - usually sterile

Extra Information: in male: dysuria, urinary frequency, urgency, low back pain