Sepsis is a life-threatening condition resulting from the body’s response to an infection, which can rapidly lead to tissue damage, organ failure, and death. Procedures to remove kidney stones, such as ureteroscopy (URS) or percutaneous nephrolithotomy (PCNL), are common but carry a risk of introducing bacteria from the urinary tract into the bloodstream. When surgical instruments disrupt natural barriers, bacteria contained within a stone can circulate, triggering an inflammatory cascade. Recognizing this complication and its early signs is important due to the speed at which sepsis progresses.
Understanding How Sepsis Develops
The mechanism behind sepsis following stone removal is rooted in the presence of bacteria within the kidney or the stone itself. Many stones, particularly struvite stones, form as a result of a chronic urinary tract infection (UTI) and contain colonies of bacteria. When a urologist fragments or manipulates a stone, these trapped bacteria are released into the urine within the kidney’s collecting system.
Procedures like PCNL and URS rely on continuous irrigation fluid to maintain visibility and flush out stone fragments. If the irrigation fluid pressure becomes too high, it can force bacteria-laden urine through tiny ruptures in the kidney lining. This process, known as pyelovenous or pyelolymphatic backflow, allows bacteria to enter the systemic circulation, a condition called bacteremia.
Once bacteria enter the bloodstream, they trigger the host’s immune system to release inflammatory molecules. This widespread, uncontrolled inflammatory response defines sepsis, causing damage far beyond the original site of infection.
The risk of systemic spread is elevated in complex or prolonged procedures. The incidence of urosepsis after these procedures ranges from 0.5% to 5.0%, with PCNL for large stones carrying a higher risk.
Recognizing Warning Signs After the Procedure
Recognizing the early warning signs of sepsis is crucial for improving patient outcomes. Sepsis symptoms often develop rapidly, usually within the first 24 to 72 hours following the procedure. A sudden, high-grade fever exceeding 100.4°F (38°C), accompanied by shaking and chills, is an early indicator of systemic infection.
Patients may experience a change in mental status, such as new confusion, disorientation, or difficulty tracking conversations. The body’s attempt to compensate can manifest as a rapid heart rate, often above 90 beats per minute, or fast, shallow breathing. Physical signs like clammy or sweaty skin may appear, even if the patient feels cold to the touch.
Extreme, unexplained pain or discomfort disproportionate to typical post-operative soreness should also raise suspicion. This discomfort may be localized to the flank or abdomen, or it can be a generalized feeling of severe illness. If any combination of these symptoms appears, the patient or caregiver must seek emergency medical attention immediately and inform the medical staff about the recent kidney stone procedure.
Patient and Procedural Risk Factors
Several factors related to the patient’s health and the nature of the surgery increase the likelihood of developing post-operative sepsis. Patients with pre-existing health conditions, such as diabetes mellitus, chronic kidney disease, or immunosuppression, have a diminished ability to fight infection and are at a significantly higher risk. Advanced age is another factor, as the immune system naturally becomes less robust over time.
A positive urine culture obtained before the surgery, indicating an active or recent urinary tract infection, is one of the strongest predictors of post-operative infection. A high bacterial load increases the chance of bloodstream contamination during manipulation. Female patients also demonstrate a slightly increased risk of urosepsis following ureteroscopy.
Procedural factors also play a substantial role in risk stratification. Surgeries that are technically complex, involve a large stone burden, or require a longer operative time are associated with greater risk. The presence of infected stones, such as struvite stones, or finding a positive culture from the stone or renal pelvis during the procedure elevates the risk. Furthermore, if the kidney was severely blocked or infected before the surgery, a condition known as obstructive pyelonephritis, the chance of developing sepsis post-procedure is higher.
Acute Medical Response and Treatment
When a patient presents with suspected sepsis, the medical response must be immediate. Rapid diagnosis involves drawing blood samples for tests such as blood cultures to identify the specific bacteria, and a lactate level to measure organ dysfunction. Elevated lactate is a marker of cellular stress and inadequate oxygen delivery, indicating potential septic shock.
Treatment begins immediately, often within the first hour of recognition, which is critical for patient survival. Initial management involves the rapid administration of broad-spectrum intravenous (IV) antibiotics, chosen to target common urologic bacteria like E. coli before culture results are available. Supportive care is initiated simultaneously, usually with large volumes of IV fluids to combat low blood pressure caused by vasodilation.
If blood pressure remains low despite fluid resuscitation, vasopressors may be administered to constrict blood vessels and stabilize circulation. Controlling the source of the infection is a necessary step that cannot be delayed. If the kidney is obstructed by stone fragments or swelling, the infected, pressurized urine must be drained immediately. This is typically achieved by placing a ureteral stent or a percutaneous nephrostomy tube, which diverts the infected urine and relieves pressure. Source control is paramount to stabilizing the patient and is often performed before definitive stone removal.
Summary and Urgency
Sepsis after kidney stone removal is a severe complication requiring immediate action. It results from the body’s reaction to bacteria entering the bloodstream during surgical manipulation. The development of high fever, persistent chills, confusion, or extreme pain following discharge should be treated as a medical emergency. Speed is the determining factor in the outcome of sepsis. Prompt recognition and immediate presentation to an emergency department allow for rapid initiation of IV antibiotics, supportive care, and draining the infected kidney.