Urosepsis - an overview | ScienceDirect Topics (2023)

Urosepsis

The principles of management of urosepsis are similar to those for patients with severe sepsis from any site. Parenteral empirical antimicrobial treatment and supportive care should be initiated promptly.¹⁴ The antimicrobials selected should provide broad-spectrum coverage for potential uropathogens, including resistant bacteria. Antimicrobial therapy should be reassessed when urine and blood culture results become available and the infecting organism and susceptibilities are identified.

Infection and Urosepsis

Although community-acquired urinary tract infections (UTIs) are very common and are considered relatively easy to treat, complicated UTIs such as those acquired in the hospital setting are a legitimate cause for concern in urology. The termcomplicated UTI connotes infections brought about by a functional or anatomic abnormality in the urinary tract, but it may also be used to indicate an infection that occurs in a patient with altered defense mechanisms.⁹¹ When an infection previously localized to the urinary tract enters the bloodstream and causes a systemic infection, urosepsis ensues.

Judicious use of prophylactic antibiotics in surgical procedures has served to minimize the incidence of these preventable yet potentially lethal complications in urologic practice.⁹² However, the rising incidence of antimicrobial resistance, especially of gram-positive pathogens such as methicillin-resistantStaphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE), can lead to treatment failure and life-threatening sepsis.⁹³ Moreover, the increasing numbers of patients who are immunocompromised either by an underlying disease (e.g., HIV/AIDS) or through concurrent medical therapy (e.g., steroids, chemotherapy)⁹⁴ also lead to greater infection risk. These risk factors are particularly relevant when surgery entails instrumentation and manipulation of the urinary tract. Given that certain host factors predispose the urologic patient to complicated infection, it is necessary to determine the need for antimicrobial prophylaxis preoperatively and to prevent the occurrence of systemic septicemia.

Both demographic factors and medical conditions play a role in susceptibility to complicated UTI. Advanced age in a patient should alert the urologist to the possible presence of UTI. The prevalence of UTI increases with age and reaches approximately 3.6% in men ≥70 years old and 7% in women ≥50 years old.⁹⁵ As previously discussed, nutritional imbalances leading to obesity and malnutrition could impair cellular immunity and thereby predispose patients to UTI. Preexisting local or systemic infections intuitively are associated with complicated UTI.

Recent antimicrobial use has been linked to complicated UTI, possibly through two mechanisms: (1) antibiotic therapy fails, and the initial infection, either systemic or local, progresses to complicated UTI or frank urosepsis; or (2) antibiotics used to eliminate competing pathogens promote the growth of resistant strains and lead to infection with a more virulent strain.⁹⁶ Diabetes mellitus not only increases the incidence of UTI in adults but also contributes to a complicated course despite antibiotic prophylaxis and treatment. This situation is the result of defects in the secretion of urinary cytokines and increased adherence of microorganisms to the uroepithelial cells in diabetic patients.⁹⁷

Discussion

A 55-year old Turkish woman presents with fever of unknown origin. She has travelled to Turkey shortly before and has a history of double heart valve replacement. Treatment with co-trimoxazole results in some improvement, but then the patient develops signs of congestive heart failure.

Urosepsis

In 20% to 30% of all septic patients, the initial infectious focus is in the urogenital tract. The most frequent causes for urosepsis are obstructive diseases of the urinary tract such as ureteral stones, anomalies, stenosis, or tumor. Early relief from the obstruction controls the infectious focus and improves organ perfusion. This is one reason why mortality in urosepsis is usually lower than that in other septic forms (Fig. 123-2).³³

Immediately after microbiological sampling of urine and blood, empiric broad-spectrum antibiotic therapy should be started parenterally. Adequate initial (e.g., in the first hour) antibiotic therapy ensures improved outcome in septic shock.^34,35 Inappropriate antimicrobial therapy in severe UTIs is linked to a higher mortality rate.³⁶ Empiric antibiotic therapy is based upon the expected bacterial spectrum, institution-specific resistance rates, specific pharmacokinetic and pharmacodynamic factors in UTIs, and individual patient characteristics.

The bacterial spectrum in urosepsis predominantly consists of Enterobacteriaceae such asE. coli,Proteus spp.,Enterobacter andKlebsiella spp., nonfermenting organisms such asP. aeruginosa, and gram-positive organisms.^37-38Candida spp. andPseudomonas spp. occur as causative agents in urosepsis mainly if the host defense is impaired. Patients with candiduria show frequently invasive candidiasis and candidemia.^39,40 Candiduria at any time in an ICU is associated with higher mortality rates (OR, 2.86).⁴⁰ Viruses are not common causes of urosepsis.

Although urosepsis is a systemic disease, the activity of an antibiotic at the site of the infection is critical. A variety of studies have shown that inflammatory mediators such as IL-6, CXC chemokines, endotoxin, or HMGB1 are produced and released in the urinary tract.^41-43 Therefore, predominantly antimicrobial substances with high activities in the urogenital tract are recommended.^44,45

The increasing antibiotic resistance rates of pathogens causing urosepsis significantly diminish the choice of antibiotics available for adequate empiric initial therapy in urosepsis. In particular, the increasing rates of Enterobacteriaceae producing ESBL pose clinically relevant problems.^5,46-48 Other recent developments of concern include increased rates of fluoroquinolone-resistant enterobacteria and vancomycin-resistant enterococci.^49,50 Currently, there are no specific pharmacokinetic/pharmacodynamic parameters available for the treatment of patients with urospesis.

UROSEPSIS

As a primary disease, urosepsis is rarely asymptomatic, except in very debilitated or immunosuppressed patients. However, as a nosocomial infection in an already critically ill patient, urosepsis may be asymptomatic and the clinician must rely on the vitals (fever, tachycardia, low blood pressure), blood work, urine analysis, and cultures to reach an accurate diagnosis.⁶

General sepsis treatment guidelines apply for urosepsis as for any sepsis. Rapid liquid repletion with concomitant parenteral wide-spectrum antibiotics should be started immediately. The source (pyelonephritis, renal or perirenal abscess, but rarely simple UTIs) should be identified.⁶ Indwelling urinary catheters should be removed and replaced only if necessary. When the source and the nature of the microorganism are known, targeted actions should be taken and antibiotic spectrum should be narrowed. The clinician should remember that even if the urinary tract is one of the most frequent sites of origin for gram-negative bacteremia, gram-positive bacteremia and fungus cannot be ignored, especially in a critically ill patient.

Complications such as adult respiratory distress syndrome and disseminated intravascular coagulation can be seen as a result of cytokine release and activation of several mediators involved in the pathophysiology of gram-negative sepsis.

Natural History & Prognosis

Answer 4: Clinical Considerations: Treatment of Endometrial Cancer in a Very Elderly Patient

Such patients are occasionally managed by our gynecologic oncology service. The family should be informed that her urosepsis must be stabilized. A nutrition consult should be obtained and parameters, such as serum prealbumin, assessed for possible intervention with enteral alimentation. A CT (or MRI) of the abdomen and pelvis should be obtained to rule out ureteral obstruction or extrauterine malignancy. We would review our own operative findings from the D&C. How large was the uterus on examination under anesthesia and by sounding? Was the cervix involved? These data would help in clinical staging and further treatment plans. She should be placed on low–molecular-weight heparin, until fully ambulatory, to avoid deep vein thrombosis and pulmonary embolism. Physical therapy should be consulted. If the clinical stage is I, we would place her on high-dose oral megestrol acetate (unless contraindicated). If she cannot undergo a major operation after these interventions, we would perform another endometrial biopsy or repeat D&C (depending on the size of the uterus) about 2 to 3 months later. If persistent invasive cancer is found, radiation should be considered. Either brachytherapy alone or with the addition of external-beam irradiation is possible. The family can be told that in this scenario, the 5-year survival rate drops about 10% for stage I disease to around 80%, compared with operative management. If there is no cancer found on repeat D&C, consideration for continued oral megestrol acetate should be given.

Getting Started

Key Differential Diagnosis Issues