55. UTI

a. Chills, fever, and flank pain. Acute pyelonephritis is a clinical syndrome of chills, fever, and flank pain that is accompanied by bacteriuria and pyuria, a combination that is reasonably specific for an acute bacterial infection of the kidney

b. Colonization. Bacteriuria without pyuria is generally indicative of bacterial colonization without infection of the urinary tract

a. Occur in patients who are hospitalized or institutionalized. Nosocomial or health care–associated UTIs occur in patients who are hospitalized or institutionalized and may be caused by Pseudomonas and other more antimicrobial-resistant strains.

b. Reinfections. Recurrent infections are hypothesized to be secondary to either bacterial persistence within the urinary tract or, more commonly, novel reinfection. Persistence, caused by the same bacterial strain, usually leads to recurrent infections in a short time frame, whereas reinfections generally occur over a more remote period. Reinfection is likely secondary to ascent of uropathogens from fecal flora into the urinary tract or from reemergence of bacteria from uroepithelial intracellular colonies

d. Antimicrobial treatment. Whether a patient receives no treatment or short-term, long-term, or prophylactic antimicrobial treatment, the risk of recurrent bacteriuria remains the same; antimicrobial treatment appears to alter only the time until recurrence

e. Minimal. The long-term effects of uncomplicated recurrent UTIs are not completely known, but so far, no association between recurrent infections and renal scarring, hypertension, or progressive renal azotemia has been established.

e. Frequent voiding. This route is further enhanced in individuals with significant soilage of the perineum with feces, women using spermicidal agents, and patients with intermittent or indwelling catheters.

b. Staphylococcus saprophyticus. S. saprophyticus is recognized as causing frequent symptomatic UTIs in young, sexually active females, whereas it rarely causes infection in males and elderly individuals.

c. Pili. Studies have demonstrated that interactions between FimH and receptors expressed on the luminal surface of the bladder epithelium are critical to the ability of many uropathogenic E. coli strains to colonize the bladder and cause disease

b. Affects bacterial virulence. This process is called phase variation and has obvious biologic and clinical implications. For example, the presence of type 1 pili may be advantageous to the bacteria for adhering to and colonizing the bladder mucosa but disadvantageous because the pili enhance phagocytosis and killing by neutrophils

. a. Increased adherence of bacteria to vaginal cells. These studies established increased adherence of pathogenic bacteria to vaginal epithelial cells as the first demonstrable biologic difference that could be shown in women susceptible to UTI

c. Voiding. Bacteria presumably make their way into the bladder fairly often. Whether small inocula of bacteria persist, multiply, and infect the host depends in part on the ability of the bladder to empty

c. Obstruction. A patient who suffers from an acute ureteral obstruction caused by a sloughed papilla and who has a concomitant UTI should have the condition treated as a urologic emergency

a. Spinal cord injuries. Of all patients with bacteriuria, no group compares in severity and morbidity with those who have spinal cord injury.

a. Squamous epithelial cells. The validation of the midstream urine specimen can be questioned if numerous squamous epithelial cells (indicative of preputial, vaginal, or urethral contaminants) are present.

a. Women. Imaging and cystoscopic evaluation are not warranted in all women with recurrent UTIs. Indeed, the yield of imaging in women without suspected complicated UTI is low and is not recommended by the American College of Radiology, the Canadian Urological Association Guidelines, or the European Association of Urology Guidelines. However, in women with risk factors for a complicated UTI the evaluation should include imaging and cystoscopy

e. CT. CT and magnetic resonance imaging are more sensitive than excretory urography or ultrasonography in the diagnosis of acute focal bacterial nephritis, renal and perirenal abscesses, and radiolucent calculi.

c. Urine level. Efficacy of the antimicrobial therapy is critically dependent on the antimicrobial levels in the urine and the length of time that this level remains above the minimum inhibitory concentration of the infecting organism. Thus resolution of infection is closely associated with the susceptibility of the bacteria to the concentration of the antimicrobial agent achieved in the urine

e. Nitrofurantoin. According to the Infectious Diseases Society of America 2010 update, nitrofurantoin 100 mg twice daily for 5 days or Bactrim DS twice daily for 3 days should be preferential regimens for the treatment of uncomplicated UTIs in women. Sensitivity to these agents should be confirmed on urine culture, especially if the patient does not report a resolution of symptoms at the end of their course

d. Indwelling orthopedic pins. Bacterial seeding of implanted orthopedic hardware is a rare but morbid event. A joint commission of the American Urological Association, the American Academy of Orthopaedic Surgeons, and infectious disease specialists convened in 2003 and released an advisory statement on antibiotic prophylaxis for urologic patients with total joint replacement. In general, antimicrobial prophylaxis for urologic patients with total joint replacements, pins, plates, or screws is not indicated. Prophylaxis is advised for individuals at higher risk of seeding a prosthetic joint and include those with recently inserted implants (within 2 years).

b. 3 days. According to IDSA guidelines, a 3-day therapy is the preferred regimen for uncomplicated cystitis in women

c. Pregnant. In populations other than those for whom treatment has been documented to be beneficial (e.g., pregnant women and patients undergoing urologic interventions), screening for or treatment of asymptomatic bacteriuria is not appropriate and should be strongly discouraged.

a. Pregnant women. In populations other than those for whom treatment has been documented to be beneficial (e.g., pregnant women and patients undergoing urologic interventions), screening for or treatment of asymptomatic bacteriuria is not appropriate and should be discouraged

e. Initial bacterial resistance. Most commonly, the bacteria are resistant to the antimicrobial agent selected to treat the infection.

a. Urine. Nitrofurantoin, which does not alter the bowel flora, is present for brief periods at high concentrations in the urine and leads to repeated elimination of bacteria from the urine, presumably by interfering with bacterial initiation of infection

b. P-piliated bacteria. If vesicourethral reflux is absent, a patient bearing the P blood group phenotype may have special susceptibility to recurrent pyelonephritis caused by E. coli that have P pili and bind to the P blood group antigen receptors

b. Cephalexin. Macrobid is concentrated in the urine and cannot treat blood-borne infections. Amoxicillin has been used to treat cystitis in pregnancy but does not have broad enough gramnegative coverage for the treatment of pyelonephritis. Levofloxacin is contraindicated in pregnancy due to possible damage to fetal cartilage, and trimethoprim should be avoided in pregnancy because it may cause fetal megaloblastic anemia, and, in the first trimester, neural tube and cardiovascular defects by inhibiting folic acid metabolism

. a. Observation. Even though the urine usually becomes sterile within a few hours of starting antimicrobial therapy, patients with acute uncomplicated pyelonephritis may continue to have fever, chills, and flank pain for several more days after initiation of successful antimicrobial therapy. They should be observed.

d. Diabetic adults. Emphysematous pyelonephritis predominantly affects female diabetics and can occur in insulin-dependent and non-insulin-dependent patients in the absence of ureteral obstruction. Nondiabetic patients can also develop this form of pyelonephritis but often have ureteric obstruction and do not seem to develop extensive disease

d. Percutaneous drainage. Although surgical drainage, or nephrectomy if the kidney is nonfunctioning or severely infected, is the classic treatment for perinephric abscesses, renal ultrasonography and CT make percutaneous aspiration and drainage of small perirenal collections possible.

e. No symptoms. There are no symptoms of chronic pyelonephritis until it produces renal insufficiency, and then the symptoms are similar to those of any other form of chronic renal failure.

d. Proteus mirabilis. Although review of the literature shows Proteus to be the most common organism involved with xanthogranulomatous pyelonephritis, E. coli is also common.

b. Malacoplakia. Malacoplakia, from the Greek word meaning “soft plaque,” is an unusual inflammatory disease that was originally described to affect the bladder. It is an inflammatory lesion described originally by Michaelis and Gutmann 1902. It was characterized by von Hansemann 1903 as soft, yellow-brown plaques with granulomatous lesions in which the histiocytes contain distinct basophilic lysosomal inclusion bodies or Michaelis-Gutmann bodies. Although its exact pathogenesis is unknown, malacoplakia probably results from abnormal macrophage function in response to a bacterial infection, which is most often E. coli.

d. Surgical removal of the hydatid cyst. Surgery remains the mainstay of treatment of renal echinococcosis. The cyst should be removed without rupture to reduce the chance of seeding, antigen reaction, and recurrence. If the cyst ruptures or cannot be removed and marsupialization is required, the contents of the cyst initially should be aspirated and filled with a scolicidal agent.

c. Hyperventilation. Even before temperature extremes and the onset of chills, bacteremic patients often begin to hyperventilate. Thus the earliest metabolic change in septicemia is a resultant respiratory alkalosis.

c. Acute pyelonephritis. Pyelonephritis develops in 1% to 4% of all pregnant women and in 20% to 40% of pregnant women with untreated bacteriuria

a. Maternal sepsis. Pregnant women with asymptomatic bacteriuria are at higher risk for developing a symptomatic UTI that results in adverse fetal sequelae, complications associated with bacteriuria during pregnancy, and pyelonephritis and its possible sequelae, such as sepsis in the mother. Therefore all women with asymptomatic bacteriuria should be treated.

d. Penicillin. The aminopenicillins and cephalosporins are considered safe and generally effective throughout pregnancy. In patients with penicillin allergy, nitrofurantoin is a reasonable alternative.

a. Asymptomatic. Most elderly patients with bacteriuria are asymptomatic

f. None of the above. The American Heart Association’s recommendations on the prevention of bacterial endocarditis are based on the patient’s risk of developing endocarditis and the likelihood that a procedure will cause bacteremia with an organism that can cause endocarditis. Antibiotic prophylaxis solely for the prevention of infectious endocarditis is not recommended for GU procedures, even in the setting of high-risk patients including individuals with prosthetic heart valves, previous bacterial endocarditis, cyanotic congenital heart disease, and systemic-pulmonary shunts or conduits

d. Catheterization. Catheter-associated bacteriuria is the most common hospital-acquired infection

a. Closed drainage. Careful aseptic insertion of the catheter and maintenance of a closed dependent drainage system are essential to minimize development of bacteriuria.

a. Clean intermittent catheterization (CIC). Although never rigorously compared with indwelling urethral catheterization, CIC has been shown to decrease lower urinary tract complications by maintaining low intravesical pressure and reducing the incidence of stones.

a. Obesity. An association between Fournier gangrene and urethral obstruction associated with strictures and extravasation and instrumentation has been well documented. Predisposing factors include diabetes mellitus, local trauma, paraphimosis, periurethral extravasation of urine, perirectal or perianal infections, and surgery such as circumcision or herniorrhaphy.

e. The effects of vaginal estrogen on recurrent UTI risk are related to modulation of local pH and vaginal microflora. Randomized controlled trials of vaginal estrogen use have not been designed to analyze outcomes such as cancer or cardiovascular disease. However, observational studies have found no increased risk of fracture or breast cancer in women who used vaginal estrogen. Vaginal estrogen is effective in preventing recurrent UTIs in postmenopausal women through lowering the vaginal pH and restoring the normal microenvironment such as lactobacilli. The beneficial effect from vaginal estrogen use can take at least 12 weeks to manifest

e. Polycystic native kidneys. Transplant recipients are at higher risk for vesicoureteral reflux. Risk factors for infection include cadaveric graft, diabetes, prolonged hemodialysis prior to transplantation, two episodes of asymptomatic bacteriuria, and female gender

f. None of the above. The American Heart Association’s recommendations on the prevention of bacterial endocarditis are based on the patient’s risk of developing endocarditis and the likelihood that a procedure will cause bacteremia with an organism that can cause endocarditis. Antibiotic prophylaxis solely for the prevention of infectious endocarditis is not recommended for GU procedures, even in the setting of high-risk patients including individuals with prosthetic heart valves, previous bacterial endocarditis, cyanotic congenital heart disease, and systemicpulmonary shunts or conduits

d. Administration of an antimicrobial agent within 60 to 120 minutes of the initiation of a procedure and for a period of time that covers the duration of the procedure. Surgical antimicrobial prophylaxis entails treatment with an antimicrobial agent before and for a limited time after a procedure to prevent local or systemic postprocedural infections

a. Enterococcus. Most gram-negative bacteria are capable of producing positive results on a nitrite test. Pseudomonas aeruginosa and most gram-positive organisms do not produce nitrites.

c. History of human papilloma virus (HPV). HPV history does not impact ability to provide an adequate sample; the other variables are important influencing factors and a catheterized urine sample should be considered in these situations.

a. Family history of postmenopausal UTIs. Family history of postmenopausal UTIs is least relevant to the patient’s immediate evaluation; the other variables list individual behaviors, infection history, and anatomic factors that can have a direct impact on the patient’s ongoing UTI diathesis. Family history of UTIs in childhood or young adulthood bears more relevance regarding structural issues (such as vesicoureteral reflux) or genetic risk factors for recurrent infections.