Uncomplicated Urinary Tract Infection Jayme Bristow PharmD Candidate UGA COP

UTI UTI is the most common bacterial infection in the ambulatory care setting in the US 8.6 million visits in % of those were women

Causes UTIs typically occur when bacteria outside the body enter the urinary tract through the urethra and begin to multiply The bladder secretes a protective coating that prevents bacteria from attaching to its wall Urine also has antibacterial properties that inhibit the growth of bacteria Bacterial bladder infections may occur in women as a result of sexual intercourse. During sexual activity, bacteria may be introduced into the bladder through the urethra Women are susceptible to lower urinary tract infections because the female genital area often harbors bacteria that can cause cystitis Most cases of cystitis are caused by Escherichia coli (E. coli), a species of bacteria commonly found in the genital area

Risk Factors Are sexually active: sexual intercourse can result in bacteria being pushed into the urethra Use certain types of birth control: women who use diaphragms are at increased risk of a UTI. Diaphragms that contain spermicidal agents further increase your risk Are pregnant: Hormonal changes during pregnancy may increase the risk of a bladder infection Interference with the flow of urine: this can occur in conditions such as a stone in the bladder or, in men, an enlarged prostate Changes in the immune system: this can occur with conditions such as diabetes, HIV infection and cancer treatment Prolonged use of bladder catheters: prolonged use can result in increased vulnerability to bacterial infections as well as bladder tissue damage

Non-Risk Factors Precoital or postcoital voiding patterns Daily beverage consumption Frequency of urination Delayed voiding habits Wiping patterns Tampon use Douching Use of hot tubs Type of underwear Body mass index

Cystitis vs Pyelonephritis Cystitis is the medical term for inflammation of the bladder Most of the time the inflammation is caused by a bacterial infection  In which case it may be referred to as a urinary tract infection

Cystitis vs Pyelonephritis Symptoms of cystitis include:  A strong, persistent urge to urinate  A burning sensation when urinating  Passing frequent, small amounts of urine  Blood in the urine (hematuria)  Passing cloudy or strong-smelling urine  Discomfort in the pelvic area  A feeling of pressure in the lower abdomen  Low-grade fever

Cystitis vs Pyelonephritis Kidney infection (pyelonephritis) is a specific type of urinary tract infection (UTI) that generally begins in your urethra or bladder and travels up into your kidneys Kidney infection can permanently damage your kidneys or the bacteria can spread to your bloodstream and cause a life- threatening infection

Cystitis vs Pyelonephritis Symptoms of pyelonephritis include;  Fever  Nausea/Vomitting  Back, side (flank) or groin pain  Abdominal pain  Frequent urination  Strong, persistent urge to urinate  Burning sensation or pain when urinating  Pus or blood in your urine (hematuria)  With or without symptoms of cystitis

Microbiology E. coli causes 75 to 95% of episodes of uncomplicated cystitis and pyelonephritis The remaining cases are caused by other Enterobacteriaceae ( Klebsiella pneumoniae) or grampositive bacteria:  Staphylococcus saprophyticus  Enterococcus faecalis  Streptococcus agalactiae (group B streptococcus)

Diagnosis Assessment for pyuria and bacteriuria is often performed with the use of commercially available dipsticks Test for leukocyte esterase:  Enzyme released by leukocytes Test for nitrites:  Some bacteria reduce urinary nitrates to nitrites Urine culture is performed to confirm the presence of bacteriuria and antimicrobial susceptibility of the infecting uropathogen

Management – Cystitis Antimicrobial drugs are routinely prescribed, the primary goal being the rapid resolution of symptoms Choice of regimen has become more complicated as resistance among the uropathogenic strains of E. coli has increased worldwide Rates of resistance to amoxicillin of 20% or higher in all regions and similar rates of resistance to trimethoprim– sulfamethoxazole in many regions

Management – Cystitis The choice of an antimicrobial agent should be individualized on the basis of:  The patient’s allergy and compliance history  Local practice patterns  The prevalence of resistance in the local community (if known)  Availability  Patient and provider threshold for failure

Management – Cystitis If a first-line antimicrobial agent is not a good choice on the basis of one or more of the previously mentioned factors, fluoroquinolones or beta lactams are reasonable alternatives It is preferable to minimize their use because of concerns about ecologic adverse effects and, with respect to beta- lactams, efficacy

Management – Pyelonephritis Most episodes of acute uncomplicated pyelonephritis are treated as outpatients Culture and susceptibility test should be performed to guide treatment Women should be admitted if:  Pyelonephritis is severe  Hemodynamic instability  Any complicating factor  Oral medications are not tolerated  There is concern regarding potential nonadherence

Recurrence – Cystitis Urinary symptoms that persist or recur within a week or two of treatment for uncomplicated cystitis suggest infection with an antimicrobial-resistant strain or, rarely, relapse Urine culture should be performed and treatment should be initiated with a broader-spectrum antimicrobial agent, such as a fluoroquinolone

Recurrence – Cystitis The vast majority of episodes of recurrent cystitis in healthy women, up to two thirds of which are recurrences involving the same strain of bacteria that caused the initial infection, are thought to be reinfections Uropathogenic strains can persist in the fecal flora for years after elimination from the urinary tract and can cause recurrent urinary tract infections

Follow Up Urine culture is unnecessary if symptoms have resolved, except in pregnant women for whom treatment of persistent asymptomatic bacteriuria is recommended Women with pyelonephritis who have;  Severe or worsening illness  Persistent fever 48 to 72 hours after the initiation of appropriate antimicrobial treatment  Symptoms suggestive of a stone, abscess, or obstruction Urologic evaluation should be performed to rule out these latter abnormalities

References “Uncomplicated Urinary Tract Infections.” N Eng J Med 2012;366: “Cystitis.” MayoClinic. Accessed 6 May /DSECTION=complications 85/DSECTION=complications “Pyelonephritis.” MayoClinic. Accessed 6 May infection/DS00593http:// infection/DS00593