Urinary Tract InfectionsHongbiao (Hank) Liu MD PhD Luna Medical Care
Urinary Tract Infections Leading cause of morbidity and health care expenditures in persons of all ages. An estimated 50 % of women report having had a UTI at some point in their lives. 8.3 million office visits and more than 1 million hospitalizations, for an overall annual cost > $1 billion.
Acute Uncomplicated Cystitis Sexually active young women. Causes: anatomy and certain behavioral factors, including delays in micturition, sexual activity, and the use of diaphragms and spermicides tract. Aggressive diagnostic work-ups are unwarranted in young women presenting with an uncomplicated episode of cystitis.
Acute Uncomplicated Cystitis The microbiology is limited to a few pathogens. 70%- 85% are caused by Escherichia coli 5-20%are caused by coagulase-negative Staphylococcus saprophyticus 5-12% are caused by other Enterobacteriaceae such as Klebsiella and Proteus.
Acute Uncomplicated Cystitis Diagnosis: direct history and PE PE: Temperature, abdominal exam, assessment of CVA tenderness, pelvic exam. H/o STD’s, new sexual partner, partner with urethral symptoms, gradual onset.
Acute Uncomplicated Cystitis Guidelines for tx of acute cystitis recommend empiric antibiotic tx. Unnecessary antibiotic use?? Clinical criteria for Dx: Dysuria, presence of > trace urine leukocytes, and presence of nitrites or... Dysuria and frequency in the absence of vaginal discharge.
Acute Uncomplicated Cystitis UA: Evaluation of midstream urine for pyuria. White blood cell casts in the urine are Dx of upper tract infection. Urine Culture: Not necessary Warranted in: Suspected complicated infection, persistent symptoms following tx, symptoms recur < 1 mo after tx.
Acute Uncomplicated Cystitis Urine dipsticks: Leukocyte esterase (pyuria), sensitivity 75-90%, specificity 95% Nitrite (Enterobacteriacea), sensitivity 35-85%, specificity 95%, false positive with phenazopyridine, beets. Microscopic evaluation for pyuria or a culture is indicated in pt with negative leukocyte esterase that have urinary symptoms.
Acute Uncomplicated Cystitis Susceptibility: E.coli 30% isolates resistance to ampicillin and sulfonamides Increasing of resistance to TMP-SMX Resistance to nitrofurantoin is <5% Resistance to fluoroquinolones <5% S.saprophyticus 3% resistant to TMP-SMX 0% resistant to nitrofurantoin 0.4% resistant to ciprofloxacin
Acute Uncomplicated Cystitis Treatment: Short course vs. prolonged tx Short course preferred except with beta-lactam agents TMP-SMX (160/800mg BID x 3) first-line tx if: no allergy to the drug, no antibiotics in the past 3 mo, no recent hospitalization. Nitrofurantoin(100mg BID x 5 days) Analgesia: Phenazopyridine 200mg TIDx2
Acute Urethral Syndrome Acute symptomatic women with dysuria and frequency with a midstream culture containing < 10(5) CFU/mL. > 10(2) CFU/mL in women with acute symptomatic pyuria = UTI Tx as an uncomplicated UTI Mycoplasma genitalium, Ureaplasma urealyticum
Acute Complicated Cystitis UTI when/with structural, functional or metabolic abnormalities (polycystic, solitary, transplant kidney;DM, CRF, indwelling cath, neurogenic bladder) or elderly, male, child, pregnant or h/o recurrent UTI) E.coli accounts for fewer than one third of complicated cases. Clinically, the spectrum of complicated UTIs may range from cystitis to urosepsis with septic shock.
Acute Complicated Cystitis Urine culture and susceptibility are necessary. These infections are usually associated with high- count bacteriuria (> 10(5) CFU/mL). MO: Proteus, Klebsiella, Pseudomonas, Serratia, and Providencia, enterococci, staphylococci and fungi AND E.coli
Acute Complicated Cystitis Empiric therapy for these patients should include an agent with a broad spectrum of activity against the expected uropathogens: fluoroquinolone, ceftazidime, cefepime, aztreonam, imipenem- cilastatin. (Obtain Ucx prior to Tx) Tx x 7-14 days Follow-up urine culture should be performed within 14 days after treatment???
Recurrent Cystitis Up to 27% of young women with acute cystitis develop recurrent UTIs. The causative organism should be identified by urine culture. Relapse: infection with the same organism (multiple relapses = complicated UTIs). Recurrence: infection with different organisms.
Recurrent Cystitis >3 UTI recurrences documented by urine Cx within one year can be managed using one of three preventive strategies:1. Acute self-treatment with a three-day course of standard therapy.2. Postcoital prophylaxis with one-half of a TMP-SMX double-strength tablet (80/400 mg).3. Continuous daily prophylaxis TMP-SMX one-half tablet per day (40/200 mg); nitrofurantoin 50 to 100 mg per day; norfloxacin 200 mg per day.
Uncomplicated Pyelonephritis Suspect if: Cystitis-like illness and accompanying flank pain Severe illness with fever, chills, nausea, vomiting, abdominal pain Gram-negative bacteremia.
Uncomplicated Pyelonephritis DX: Clinical, confirm with: UA:pyuria and/or WBC casts UCx with > 10 (5) CFU/mL (80%) Tx: 14 days total Oral: TMP/SMX, fluoroquinolones IV: 3rd gen cephalosporin, aztreonam, quinolones, aminoglycoside
Uncomplicated Pyelonephritis Pt with symptoms after 3 days of appropriate antimicrobial tx should be evaluated by renal US or CT for obstruction or abscess.
UTI in Men At risk: Older men with prostatic disease, UT instrumentation, anal sex, or partner colonized with uropathogens. UCx: 10 (3) CFU/mL sensitivity and specificity 97%. Additional studies? Notnecessary in young healthy men who have a single episode.
UTI in Men Tx: Uncomplicated cystitis: TMP/SMX or fluoroquinolones x 7 days Complicated cystitis: Fluoroquinolones x 7-14 days Bacterial prostatitis: Fluoroquinolone x 6-12 weeks
Catheter-Associated UTI Risk of bacteriuria is ~ 5%/day (long term catheter bacteriuria is inevitable). 40% of nosocomial infections Most common source of gram-negative bacteremia. Dx: Ucx 10 (2) CFU/mL MO: E.coli, Proteus, Enterococcus, Pseudomona, Enterobacter, Serratia, Candida
Catheter-Associated UTI Mild to mod: oral quinolones10-14days Severe infection: IV/oral 14-21days Asymptomatic bacteriuria in pt with an indwelling Foley should not be Tx unless they are immunosuppressed, have risk of bacterial endocarditis or pt who are about to undergo urinary tract instrumentation.
Asymptomatic Bacteriuria UCx: > 10(5)CFU/mL with no symptoms Three groups of pt with asymptomatic bacteruria have been shown to benefit from tx: Pregnant Renal transplant Pt who are about to undergo urinary tract procedures.
Pregnant patients Asymptomatic bacteriuria: two consecutive voided urine specimens with isolation of the same bacterial strain >10(5) or a single cath urine specimen. Nitrofurantoin 100mg BID x 5-7 days Amoxi/Clav 500mg BID or 250 TID x 7days Fosfomycin 3g PO x 1
Interstitial Cystitis Frequency, urgency, urge incontinence with periurethral and suprapubic pain on bladder filling that is improved by voiding. Terminal hematuria may be present. Etiology. Unclear (autoimmune, altered glycosaminoglycal layer, allergic)
Interstitial Cystitis TX Refer to urology for cystoscopy. Dietary modifications Behavioral modifications Rx: Pyridium Pentosan polysulfate 100mg TID x 6mo to 2 years. Amitriptyline 10-75mg QHS