# Clinical Cases: Sepsis

## Case 1: Sepsis from Urinary Source

### Patient Presentation
A 76-year-old woman with a history of type 2 diabetes and recurrent urinary tract infections presents with confusion, fever, and decreased oral intake for 2 days. Her daughter reports she has been more tired than usual and not acting like herself. She lives independently but needed help getting dressed today. She has an indwelling urinary catheter that was placed 3 weeks ago for urinary retention.

### Vital Signs
- Blood Pressure: 88/52 mmHg
- Heart Rate: 108 bpm
- Respiratory Rate: 24/min
- Oxygen Saturation: 94% on room air
- Temperature: 39.2°C

### Physical Examination
- General: Ill-appearing, confused, oriented to name only
- Cardiovascular: Tachycardic, regular rhythm, warm extremities
- Pulmonary: Clear
- Abdomen: Suprapubic tenderness, no rebound
- Skin: Warm, flushed
- Foley catheter: Cloudy urine with sediment

### Laboratory Results
- **WBC**: 18,200/μL with 22% bands
- **Creatinine**: 2.4 mg/dL (baseline 1.0)
- **Lactate**: 4.2 mmol/L
- **Urinalysis**: Large leukocyte esterase, positive nitrites, >100 WBC/hpf, bacteria present
- **Blood glucose**: 320 mg/dL

### Clinical Image
![Sepsis Pathway](image_01.png)
*Figure 1: Diagram illustrating the pathophysiology of sepsis: infection triggers systemic inflammatory response leading to organ dysfunction through cytokine release, endothelial dysfunction, and microcirculatory failure.*

**Image Source**: Educational illustration for teaching purposes.

### Questions

1. **What is the Sepsis-3 definition of sepsis?**
   - A) SIRS criteria plus suspected infection
   - B) Life-threatening organ dysfunction caused by dysregulated host response to infection
   - C) Bacteremia with fever
   - D) Any infection requiring hospitalization

2. **What is this patient's qSOFA score?**
   - A) 0
   - B) 1
   - C) 2
   - D) 3

3. **Does this patient meet criteria for septic shock?**
   - A) No, blood pressure is not low enough
   - B) Yes, she has sepsis with hypotension and lactate >2 despite fluid resuscitation
   - C) Cannot determine without central line
   - D) Shock only defined by need for vasopressors

4. **What are the components of the Hour-1 Bundle for sepsis?**

5. **What is the appropriate empiric antibiotic choice for urosepsis?**

### Answers

1. **B) Life-threatening organ dysfunction caused by dysregulated host response to infection** - Sepsis-3 (2016) defines sepsis as infection plus organ dysfunction, identified by increase in SOFA score ≥2 points. This replaced the older SIRS-based criteria.

2. **D) 3** - qSOFA (quick SOFA) criteria:
   - Respiratory rate ≥22: Yes (24) = 1 point
   - Altered mental status: Yes (confused) = 1 point
   - Systolic BP ≤100: Yes (88) = 1 point
   - Total = 3 points; score ≥2 suggests increased mortality risk

3. **B) Yes, she has sepsis with hypotension and lactate >2 despite fluid resuscitation** - Septic shock = sepsis with:
   - Persistent hypotension requiring vasopressors to maintain MAP ≥65, AND
   - Lactate >2 mmol/L despite adequate fluid resuscitation
   - This patient likely has septic shock given her presentation; formal diagnosis requires demonstrating fluid unresponsiveness.

4. **Hour-1 Bundle for sepsis**:
   - **Measure lactate** (remeasure if initial >2 mmol/L)
   - **Obtain blood cultures** before antibiotics
   - **Administer broad-spectrum antibiotics**
   - **Begin rapid fluid resuscitation** (30 mL/kg crystalloid for hypotension or lactate ≥4)
   - **Apply vasopressors** if hypotensive during or after fluid resuscitation (target MAP ≥65)
   - Goal: Complete all elements within 1 hour of sepsis recognition

5. **Empiric antibiotics for urosepsis**:
   - Piperacillin-tazobactam, OR
   - Ceftriaxone (if low ESBL risk), OR
   - Cefepime, OR
   - Carbapenem (if high ESBL/resistance risk)
   - Consider adding vancomycin if enterococcal coverage needed
   - Remove/replace the Foley catheter
   - De-escalate based on culture and sensitivities

---

## Case 2: Sepsis with Multi-Organ Dysfunction

### Patient Presentation
A 62-year-old man with a history of alcohol use disorder presents with 3 days of right upper quadrant pain, fever, and jaundice. He reports rigors and appears quite ill. He has not seen a doctor in years and has no prior abdominal surgery.

### Vital Signs
- Blood Pressure: 78/45 mmHg
- Heart Rate: 122 bpm
- Respiratory Rate: 28/min
- Oxygen Saturation: 91% on room air
- Temperature: 39.8°C

### Physical Examination
- General: Toxic-appearing, icteric, diaphoretic
- Cardiovascular: Tachycardic, cool and mottled extremities
- Pulmonary: Tachypneic, bibasilar crackles
- Abdomen: RUQ tenderness with voluntary guarding, positive Murphy's sign
- Skin: Jaundiced, mottled lower extremities

### Laboratory Results
- **WBC**: 24,500/μL with 30% bands
- **Hemoglobin**: 11.2 g/dL
- **Platelets**: 68,000/μL
- **Creatinine**: 3.1 mg/dL (baseline unknown)
- **Total bilirubin**: 8.4 mg/dL
- **AST/ALT**: 180/210 U/L
- **Alkaline phosphatase**: 420 U/L
- **Lactate**: 6.8 mmol/L
- **INR**: 1.8
- **ABG**: pH 7.28, PaCO2 28, PaO2 68

### Imaging
- **RUQ ultrasound**: Dilated common bile duct (12 mm), gallstones, gallbladder wall thickening

### Clinical Image
![Cholangitis Ultrasound](image_02.png)
*Figure 2: Right upper quadrant ultrasound demonstrating dilated common bile duct with shadowing gallstones, consistent with choledocholithiasis causing acute cholangitis.*

**Image Source**: Educational illustration for teaching purposes.

### Questions

1. **What is Charcot's triad and what additional findings suggest Reynolds' pentad?**
   - A) Fever, jaundice, RUQ pain; add hypotension and altered mental status
   - B) Fever, jaundice, tachycardia
   - C) RUQ pain, nausea, vomiting
   - D) Elevated bilirubin, elevated ALP, dilated CBD

2. **Calculate this patient's SOFA score based on available data.**
   - A) 4
   - B) 8
   - C) 12
   - D) Cannot calculate

3. **What is the definitive treatment for acute cholangitis?**
   - A) Antibiotics alone
   - B) Biliary decompression (ERCP or PTC) plus antibiotics
   - C) Cholecystectomy
   - D) Conservative management

4. **How should vasopressor therapy be initiated in septic shock?**

5. **What is the significance of the elevated lactate and how should it guide management?**

### Answers

1. **A) Fever, jaundice, RUQ pain; add hypotension and altered mental status** - Charcot's triad (fever, jaundice, RUQ pain) suggests cholangitis. Reynolds' pentad adds hypotension and altered mental status, indicating severe/suppurative cholangitis with high mortality requiring emergent intervention.

2. **Approximate SOFA score calculation** (varies by exact parameters):
   - Respiratory (PaO2/FiO2 ~324 on RA): 0-1 points
   - Coagulation (platelets 68K): 2 points
   - Liver (bilirubin 8.4): 2 points
   - Cardiovascular (MAP <70, requiring pressors): 3-4 points
   - CNS (potentially altered): 1-2 points
   - Renal (Cr 3.1): 2 points
   - **Estimated total: 10-13 points** - indicates severe organ dysfunction

3. **B) Biliary decompression (ERCP or PTC) plus antibiotics** - Acute cholangitis requires:
   - Source control through biliary drainage (ERCP with sphincterotomy preferred)
   - Emergent drainage (<24 hours) for severe cholangitis
   - Broad-spectrum antibiotics covering enteric gram-negatives and anaerobes
   - PTC (percutaneous transhepatic cholangiography) if ERCP fails or unavailable

4. **Vasopressor initiation in septic shock**:
   - Start vasopressors if MAP <65 despite fluid resuscitation (or during resuscitation if severe hypotension)
   - **Norepinephrine** is first-line vasopressor
   - Target MAP ≥65 mmHg
   - Add **vasopressin** (up to 0.03-0.04 units/min) as second agent if refractory
   - Add **epinephrine** or **dobutamine** if cardiac dysfunction present
   - Consider **hydrocortisone** 200 mg/day if vasopressor requirements are high or increasing

5. **Significance of elevated lactate**:
   - Lactate >2 mmol/L indicates tissue hypoperfusion
   - Lactate >4 mmol/L associated with significantly increased mortality
   - Serial lactate measurements guide resuscitation adequacy
   - Target: Normalization of lactate (or >10% decrease per 2 hours)
   - Persistent elevation despite treatment suggests ongoing shock or inadequate source control
   - This patient's lactate of 6.8 indicates severe tissue hypoperfusion

---

## Case 3: Sepsis Resuscitation and Reassessment

### Patient Presentation
A 55-year-old man with no significant medical history presents with 2 days of fever, productive cough, and worsening shortness of breath. Chest X-ray shows right lower lobe consolidation. Initial vitals show: BP 95/60, HR 105, RR 24, T 38.9°C, SpO2 92% on room air. Lactate is 3.8 mmol/L. He receives 30 mL/kg crystalloid and ceftriaxone plus azithromycin.

### Post-Resuscitation Assessment (2 hours later)
- Blood Pressure: 102/65 mmHg (MAP 77)
- Heart Rate: 95 bpm
- Respiratory Rate: 20/min
- Oxygen Saturation: 96% on 2L NC
- Urine output: 60 mL in past hour
- Repeat lactate: 2.4 mmol/L
- Mental status: Alert and oriented

### Physical Examination Post-Fluids
- General: Improved, more alert
- Cardiovascular: Regular rhythm, warm extremities, capillary refill <2 seconds
- Pulmonary: Crackles at right base, improved work of breathing
- Extremities: No mottling

### Clinical Image
![Sepsis Resuscitation Goals](image_03.png)
*Figure 3: Algorithm for sepsis resuscitation showing dynamic assessment of fluid responsiveness and perfusion markers.*

**Image Source**: Educational illustration for teaching purposes.

### Questions

1. **What markers indicate adequate resuscitation in this patient?**
   - A) Normal blood pressure only
   - B) Improved MAP, decreasing lactate, adequate urine output, improved mental status, warm extremities
   - C) Absence of fever
   - D) Normal heart rate

2. **What is the role of dynamic measures of fluid responsiveness?**
   - A) Replacing clinical assessment
   - B) Guiding further fluid administration to avoid both under- and over-resuscitation
   - C) Determining antibiotic choice
   - D) Predicting mortality

3. **What is the appropriate duration of antibiotic therapy for uncomplicated pneumonia with sepsis?**
   - A) 3 days
   - B) 5-7 days
   - C) 14 days
   - D) 21 days

4. **What are the potential harms of excessive fluid resuscitation?**

5. **When should corticosteroids be considered in septic shock?**

### Answers

1. **B) Improved MAP, decreasing lactate, adequate urine output, improved mental status, warm extremities** - Multiple markers of perfusion should be assessed:
   - MAP ≥65 mmHg
   - Lactate clearing (this patient: 3.8 → 2.4 mmol/L)
   - Urine output ≥0.5 mL/kg/hr
   - Mental status improvement
   - Normalization of skin perfusion (warm, not mottled)

2. **B) Guiding further fluid administration to avoid both under- and over-resuscitation** - Dynamic measures include:
   - Passive leg raise response
   - Pulse pressure variation (mechanically ventilated)
   - Stroke volume variation
   - IVC collapsibility (limited accuracy)
   - These help determine if patient will benefit from additional fluids vs. moving to vasopressors

3. **B) 5-7 days** - For most pneumonia with sepsis, 5-7 days is sufficient if clinical improvement occurs. Procalcitonin can guide discontinuation. Longer courses may be needed for:
   - Pseudomonas or MRSA
   - Lung abscess or empyema
   - Immunocompromised patients

4. **Harms of excessive fluid resuscitation**:
   - Pulmonary edema and worsening respiratory failure
   - Peripheral edema and impaired wound healing
   - Intra-abdominal hypertension/abdominal compartment syndrome
   - Dilutional coagulopathy
   - Increased mortality in some studies (FEAST trial, CLOVERS trial suggests equipoise)
   - Need for prolonged mechanical ventilation
   - Goal is "just enough" fluid to optimize perfusion

5. **Corticosteroid indications in septic shock**:
   - Consider if vasopressor requirements are escalating or persistently high
   - Typically hydrocortisone 200 mg/day (50 mg IV q6h or 200 mg continuous infusion)
   - Survival benefit in refractory shock (APROCCHSS trial)
   - May speed shock reversal (ADRENAL trial)
   - Do not routinely test cortisol levels
   - Discontinue once vasopressors weaned

---

## Learning Points

1. **Sepsis-3 definition** requires infection plus organ dysfunction (SOFA score increase ≥2); septic shock adds hypotension requiring vasopressors and lactate >2 despite fluids.

2. **Hour-1 Bundle** includes lactate measurement, blood cultures, antibiotics, and fluid resuscitation initiated within 1 hour.

3. **Norepinephrine** is the first-line vasopressor for septic shock; target MAP ≥65 mmHg.

4. **Source control** (e.g., drainage of abscess, removal of infected catheter, biliary decompression) is essential and should not be delayed.

5. **Reassessment** of perfusion markers guides ongoing resuscitation; both under-resuscitation and over-resuscitation can cause harm.