Definition and Criteria of Urosepsis
Urosepsis is defined as sepsis caused by an infection originating from the urogenital tract, characterized by life-threatening organ dysfunction resulting from a dysregulated host response to urinary tract infection. 1
Core Definition
The fundamental definition follows the Sepsis-3 consensus criteria, which defines sepsis as life-threatening organ dysfunction caused by a dysregulated host response to infection. 1 When this sepsis originates from the urogenital tract, it is specifically termed urosepsis. 2, 3
Clinical Diagnostic Criteria
Organ dysfunction is clinically indicated by an increase in Sequential Organ Failure Assessment (SOFA) score of 2 points or more. 1
For rapid bedside identification, the quick SOFA (qSOFA) score has been developed and includes: 1
- Respiratory rate ≥22 breaths/min
- Altered mental status
- Systolic blood pressure ≤100 mmHg
The presence of two or more qSOFA criteria should trigger immediate concern for sepsis. 1
Underlying Urinary Tract Infection Characteristics
Urosepsis almost exclusively develops from complicated urinary tract infections with involvement of parenchymatous urogenital organs (kidneys, prostate). 3, 4 The underlying UTI typically involves: 5
- Obstruction at any site in the urinary tract
- Presence of foreign bodies (indwelling catheters)
- Incomplete voiding
- Recent instrumentation
- Host factors (male gender, pregnancy, diabetes, immunosuppression)
Septic Shock Criteria
When urosepsis progresses to septic shock, it is defined as a subset of sepsis where underlying circulatory and cellular/metabolic abnormalities are profound enough to substantially increase mortality. 1 This requires: 1
- Persistent hypotension (SBP <90 mmHg or MAP <65 mmHg) despite adequate fluid resuscitation, OR
- Lactate >4 mmol/L after fluid resuscitation
Important Clinical Context
Approximately 25-30% of all sepsis cases are urosepsis. 3, 4, 6 The mortality rate remains approximately 10% even with optimal treatment, making early recognition critical. 1
Key Diagnostic Pitfalls to Avoid:
The Sepsis-3 guidelines discontinued the use of SIRS (Systemic Inflammatory Response Syndrome) criteria for sepsis classification, though SIRS remains useful as a screening tool. 1 The expanded diagnostic criteria for sepsis now include: 1
- General parameters: Fever >38.3°C, hypothermia <36°C, tachycardia, tachypnea, altered mental status
- Inflammatory parameters: Elevated C-reactive protein or procalcitonin >2 SD above normal
- Hemodynamic parameters: Arterial hypotension, mixed venous oxygen saturation >70%
- Organ dysfunction parameters: Hypoxemia, oliguria, creatinine elevation, coagulation abnormalities, thrombocytopenia
- Tissue perfusion parameters: Hyperlactatemia >3 mmol/L, decreased capillary refill
Clinical Recognition Framework
The diagnosis requires both evidence of infection from the urogenital tract and evidence of organ dysfunction. 1, 6 Time from admission to effective treatment is the most critical factor determining outcomes—the shorter the interval, the higher the success rate. 3, 4