HIGH-YIELD Q&A REVIEW FOR CLIN MED:
INFECTIOUS DISEASE EXAM 1 — SIRS, SEPSIS, AND
RELATED CONDITIONS
Q: What is a Systemic Inflammatory Response Syndrome (SIRS)?
A: SIRS is a widespread, excessive inflammatory reaction triggered by a harmful
stressor such as infection, trauma, burns, or pancreatitis.
Q: What criteria are used to diagnose SIRS?
A: A diagnosis requires two or more of the following abnormalities:
Temperature: >100.4°F (38°C) or <96.8°F (36°C)
Heart rate: >90 bpm
Respiratory rate: >20 breaths/min or PaCO₂ <32 mmHg
WBC count: >12,000/mm³ or <4,000/mm³
Q: Can SIRS develop without an infection?
A: Yes. Non-infectious causes include trauma, burns, pancreatitis, and other severe
physiological insults.
Q: What does SIRS commonly progress to when an infection is present?
A: Sepsis.
Q: Complete the statement: “Not all SIRS is ______, but all ______ involves
SIRS.”
A: Not all SIRS is septic, but all sepsis involves SIRS.
,Q: Which category of organisms tends to cause more severe sepsis?
A: Gram-negative bacteria, often due to endotoxin release.
Q: What is the most common cause of sepsis?
A: Pneumonia.
Q: What condition frequently progresses to SIRS/sepsis, especially in diabetics and
catheterized patients?
A: Pyelonephritis.
Q: Which organisms are linked to toxic shock syndrome leading to SIRS?
A: Staphylococcus aureus and Streptococcus pyogenes, often seen in cellulitis,
abscesses, or necrotizing fasciitis.
Q: Roughly what percentage of ED patients with SIRS actually have an infection?
What should always be investigated?
A: About 25%. Always determine the underlying cause, not every case is
infectious.
Q: What vital sign patterns are common in SIRS?
A:Fever or hypothermia (hypothermia especially in elderly)
Tachycardia (compensatory response)
Tachypnea (early respiratory alkalosis)
,Q: What does normal blood pressure indicate early in SIRS?
A: Early BP may be normal. Hypotension suggests progression toward shock or
another serious process.
Q: In adults over 65, what does acute confusion often indicate during SIRS
evaluation?
A: Possible hypotension or poor perfusion—monitor frequently.
Q: What physical exam findings point toward different SIRS sources?
Pneumonia: crackles, decreased breath sounds
Pancreatitis/perforation: abdominal tenderness or guarding
Cellulitis/wound infection: warmth, redness, swelling
Pyelonephritis: costovertebral angle tenderness
Q: Why is it important to trend values over time?
A: Serial measurements reveal deterioration or improvement; a single reading can
be misleading due to stress or anxiety.
Q: What medications should you review while evaluating SIRS?
A:
Beta blockers → may hide tachycardia
Antipyretics → may suppress fever
, Q: How do elderly patients commonly present despite serious infection?
A: With minimal fever, subtle symptoms, or a normal WBC count, making
diagnosis more challenging.
Q: What four major signs show SIRS progression to severe illness?
Low urine output → suggests kidney hypoperfusion
Altered mental status → reduced cerebral perfusion
Peripheral mottling/cyanosis → poor tissue perfusion
Respiratory distress → worsening oxygen demand, possible ARDS
Q: What are essential labs when evaluating SIRS?
A:
CBC
BMP
Lactate (elevated = major warning sign)
Liver function tests (LFTs)
Findings may include leukocytosis or leukopenia, rising creatinine, electrolyte
abnormalities, high lactate, elevated transaminases, or bilirubin.
Q: When infection is suspected in SIRS, what is the first step?
A: Obtain cultures before giving antibiotics, including:
Two sets of blood cultures
Urine culture
INFECTIOUS DISEASE EXAM 1 — SIRS, SEPSIS, AND
RELATED CONDITIONS
Q: What is a Systemic Inflammatory Response Syndrome (SIRS)?
A: SIRS is a widespread, excessive inflammatory reaction triggered by a harmful
stressor such as infection, trauma, burns, or pancreatitis.
Q: What criteria are used to diagnose SIRS?
A: A diagnosis requires two or more of the following abnormalities:
Temperature: >100.4°F (38°C) or <96.8°F (36°C)
Heart rate: >90 bpm
Respiratory rate: >20 breaths/min or PaCO₂ <32 mmHg
WBC count: >12,000/mm³ or <4,000/mm³
Q: Can SIRS develop without an infection?
A: Yes. Non-infectious causes include trauma, burns, pancreatitis, and other severe
physiological insults.
Q: What does SIRS commonly progress to when an infection is present?
A: Sepsis.
Q: Complete the statement: “Not all SIRS is ______, but all ______ involves
SIRS.”
A: Not all SIRS is septic, but all sepsis involves SIRS.
,Q: Which category of organisms tends to cause more severe sepsis?
A: Gram-negative bacteria, often due to endotoxin release.
Q: What is the most common cause of sepsis?
A: Pneumonia.
Q: What condition frequently progresses to SIRS/sepsis, especially in diabetics and
catheterized patients?
A: Pyelonephritis.
Q: Which organisms are linked to toxic shock syndrome leading to SIRS?
A: Staphylococcus aureus and Streptococcus pyogenes, often seen in cellulitis,
abscesses, or necrotizing fasciitis.
Q: Roughly what percentage of ED patients with SIRS actually have an infection?
What should always be investigated?
A: About 25%. Always determine the underlying cause, not every case is
infectious.
Q: What vital sign patterns are common in SIRS?
A:Fever or hypothermia (hypothermia especially in elderly)
Tachycardia (compensatory response)
Tachypnea (early respiratory alkalosis)
,Q: What does normal blood pressure indicate early in SIRS?
A: Early BP may be normal. Hypotension suggests progression toward shock or
another serious process.
Q: In adults over 65, what does acute confusion often indicate during SIRS
evaluation?
A: Possible hypotension or poor perfusion—monitor frequently.
Q: What physical exam findings point toward different SIRS sources?
Pneumonia: crackles, decreased breath sounds
Pancreatitis/perforation: abdominal tenderness or guarding
Cellulitis/wound infection: warmth, redness, swelling
Pyelonephritis: costovertebral angle tenderness
Q: Why is it important to trend values over time?
A: Serial measurements reveal deterioration or improvement; a single reading can
be misleading due to stress or anxiety.
Q: What medications should you review while evaluating SIRS?
A:
Beta blockers → may hide tachycardia
Antipyretics → may suppress fever
, Q: How do elderly patients commonly present despite serious infection?
A: With minimal fever, subtle symptoms, or a normal WBC count, making
diagnosis more challenging.
Q: What four major signs show SIRS progression to severe illness?
Low urine output → suggests kidney hypoperfusion
Altered mental status → reduced cerebral perfusion
Peripheral mottling/cyanosis → poor tissue perfusion
Respiratory distress → worsening oxygen demand, possible ARDS
Q: What are essential labs when evaluating SIRS?
A:
CBC
BMP
Lactate (elevated = major warning sign)
Liver function tests (LFTs)
Findings may include leukocytosis or leukopenia, rising creatinine, electrolyte
abnormalities, high lactate, elevated transaminases, or bilirubin.
Q: When infection is suspected in SIRS, what is the first step?
A: Obtain cultures before giving antibiotics, including:
Two sets of blood cultures
Urine culture
