Presentation on theme: "Genitourinary Tract Infections: An Evidence-Based Approach"— Presentation transcript:
1 Genitourinary Tract Infections: An Evidence-Based Approach Ralph Gonzales, MD, MSPHAssociate Professor of Medicine; Epidemiology & Biostatistics
2 Self-Assessment Questions -35 yo woman calls with 2-3 days of painful urination, increased urinary frequency and urgency.a) What are the key questions that will help determine if she can be treated by telephone?b) If she fulfills criteria for telephone treatment, what is her probability of having a true UTI?c) If she happened to stop by your office, is there any value to performing a urinalysis?d) What would you treat her with?e) Does she need follow-up appointment or urine culture?f) Patient doesn’t get better, dysuria continues. Other causes?
3 Self-Assessment Questions -35 yo woman calls with 4-5 days of new, foul-smelling vaginal discharge. a) What are the key questions that will help determine if she can be treated by telephone?b) What is her probability of having a candidal vaginitis (ie, available OTC therapy)?c) How helpful are findings on history and physical examination in establishing an etiology?d) How helpful is microscopy?e) What management options should be considered for recurrent yeast infections?
4 Background: Acute Uncomplicated UTI is Common Uncomplicated UTI is an extremely common disorder in womenOver 7 million office visits annuallyAffects half of women at least once during their lifetimeDirect costs attributed to these infections in the US: $1 billion yearly
5 Background: Microbiology and Pathogenesis of Cystitis Organisms:E. coli, S. saprophyticus, Proteus, KlebsiellaPathogenesis:Fecal flora Vaginal introitus Urethra Bladder
6 Important Risk Factors for Cystitis in Women Past history of cystitis, especially if recurrentRecent sexual intercourseRecent diaphragm and/or spermicide useUnmarriedLack of urination after sexual intercoursePresence of asymptomatic bacteruria
7 Clinical Manifestations of UTI Clinical features of cystitisDysuria +/- frequency, urgency, suprapubic painClinical features of pyelonephritisFever, flank pain, CVA tenderness, nausea, vomitingDifferential DiagnosisFor cystitis: urethritis or vaginitisFor pyelonephritis: an abdominal process
8 Clinical Features of Complicated UTIs recent UTIstructural abnormalitiesGenetic/surgical/nephrolithiasisdiabetesimmunosuppressionpregnancyurethral instrumentationRed Flags…
9 How Good is History for the Diagnosis of Cystitis (vs. vaginitis)?
10 Positive Predictive Values for Combinations of Symptoms Prob UTI, % Summary LR-Dysuria Present-Frequency Present-Vaginal Discharge Absent-Vaginal Irritation AbsentOverall %-Dysuria Absent-Vag D/C or Irritation PresentOverall %-Dysuria or Frequency Present-Vag D/C or Irritation AbsentOverall %Bent et al, JAMA 2002
11 How Good are Lab Tests for the Diagnosis of Cystitis (vs. vaginitis)?
12 How Effective is Treatment of Cystitis? Pooled Results from RCTs
13 Irritable Voiding Symptoms 35 yo woman c/o 2-3 d painful urination, increased frequency, urgency. Denies fever, back pain.Question #1:When should I perform urinalysis?
14 Urinary Tract Infections -Test Characteristics (Bent et al) Likelihood Ratiospositive negativeDysuria ( ) 0.5 ( )Frequency ( ) 0.6 ( )Hematuria ( ) 0.9 ( )Fever ( ) 0.9 ( )Flank Pain ( ) 0.9 ( )Vaginal Discharge (Hx) ( ) 3.1 ( )Vaginal Irritation ( ) 2.7 ( )Back Pain ( ) 0.8 ( )Vaginal Discharge (PEx) ( ) 1.1 ( )CVAT ( ) 0.9 ( )UrinalysisMAIN FINDINGS from a meta-analysis… thus, aggregated CIs.Multiple voiding symptoms increase probabilityNotice impact of absence of vaginitis…Let’s see how this plays-out in real life…What do people think is the baseline probability of UTI in a woman who present with voiding symptoms?
15 Goal of Diagnostic Testing Treatment ThresholdDiagnostic Threshold0%50%100%Probability of Disease
16 Goal of Diagnostic Testing Treatment ThresholdDiagnostic Threshold0%50%100%Probability of Disease
17 Dysuria Case UTI Prob1.5dys*1.8freq*3.1d/c-*2.7irr-=23Step 1:-12/88 = 0.141Step 2:x 23 = 3.22Step 3:-3.22 /4.22 = 76%
18 UTI Post-Test Probabilities Well, it varies quite a bit. I’m using 12% from Komaroff...PreTest ProbBent et al.
20 Voiding symptoms cont. Question #1: Why perform urinalysis? Positive test: ppv = 93%Negative test: npv = 49%You diagnose uncomplicated UTI and refrain from performing UA… what are your treatment options?
21 Uncomplicated UTI RxTMP-sulfa DS bid x 3 daysciprofloxacin, bid x 3 dayskeflex 250 tid x 7 daysmacrobid 100 bid x 7 daysamoxicillin 500 tid x 7 daysFollow-up: No visit or Cx if asymptomatic after 3 days, else return for re-eval.Prevention: avoid spermicides; sexual activity?Cranberry
22 Suspected UTI Algorithm Woman > 1 UTI SxyesRisk Factors?Consider UCx, Empirial RxyesFever, Back Pain, N/V?Consider UCx, Empirial RxyesVaginitis Sx?About 20% UTIPerform PelvicMultiple UTI Sx PresentyesHigh Prob UTI,Rx w/o TestingPerform UrinalysisAdapted from Bent et al
24 STDs can present with dysuria: -gonorrhea, chlamydia, trichomonas Shapiro et al. Bronx, NY, ED setting (Acad Emerg Med. 2005)All women had straight cath urine cultures and pelvic examsUsed low bacteria count criteria for UTI in symptomatic women (100 cfu)Excluded if new vaginal D/C or other reasons to suspect STD presentMean duration of symptoms: 6.8 daysRESULTSUrine culture (+) = 57%Chlamydia (+) = 10%; GC (+) = 1% (n=1); Trich (+) = 8%STD rates equivalent in UCx positive and negative groups**Only predictor of STD was # sexual partners in past yearConclusion: Consider STD testing all women with dysuria seeking ED care, particularly those with >1 sexual partner in the past year.
25 Is Non-Invasive STD Testing Ready for Prime Time?
26 Non-invasive (urine) testing for GC and chlamydia Systematic reviewCook et al. Ann Intern Med 2005;142:Pooled PooledSensitivity SpecificityPolymerase chain reaction >97%-chlamydia women/men %/84%-GC women %Transcription-mediated amplification >97%-chlamydia women %/88%-GC women %Strand displacement amplication >97%-chlamydia women %/93%-GC women %Conclusion: non-invasive testing equivalent to cervical swab testingExcept for GC PCR?confirmatory test when screening low (<5%) prevalence populationIf spec=98%, then about 1/3 positives are false-positivesIf spec>99%, probably not necessary…
28 Vaginitis Symptoms35 yo woman c/o 4-5 days of foul-smelling, cheesy vaginal discharge and severe itching. Calls by telephone.Question #1:What clinical features can be used to reliably diagnose vulvovaginal candidiasis?When should I perform microscopy?
29 Etiology of Vaginitis in PC 40% Bacterial Vaginosis30% Unknown20% Candida10% TrichomonasOther CausesGC/chlamydia?… investigate when fever/lower abd painHSVallergic reaction (chemical, latex, semen)atrophic vaginitis
30 Challenges in History Women buying OTC yeast preps candida=33%; BV=19%; mixed=21%; normal exam=12%; trichomonas=2%Patients and physicians disagree on key findingspatient physicianclear d/c 21% %yellow d/c 15% %white/gray d/c 42% %Poor agreement between call center nurse diagnosis and physicianIf a woman presents with suspected yeast… ppv goes from 20% to 33%All of these problems have led toward recommendations for accurate diagnosis to be based on physical examination
31 Vaginitis -Likelihood Ratios for Hx/PEx (Anderson et al) positive negativeYEASTCheesy Discharge ( ) 0.5 ( )Watery Discharge ( ) 1.5 ( )Itching ( ) 0.3 ( )Chief Complaint ( ) 0.8 ( )Malodor ( ) ( )Curdy D/C or Vulvar Inflamm (8.8-32) ( )Curdy D/C + Itching (20-100) ( )Fishy Odor (PEx) (0-0.5) ( )BACTERIAL VAGINOSISMalodor (Hx) ( ) 0.07* ( )“High Cheese” Odor (PEx) ( ) ( )MAIN FINDINGS** tricky, since unlike PNA and UTI… we are trying to diagnose specific etiologies… So each cause get’s its own set of LRsWARNING… many of these studies are single or multiple small trials… hence the wide confidence intervals.Watery does not equate with YeastMalodor does no equate with Yeastvulvar/vaginal inflammation (erythema, edema, excoriations) are all strong predictors of Yeast
32 Candida Vaginitis Post-Test Probabilities .So, you might perform microscopy to confirm that vulvar inflammation is due to yeast… when positive it yields a 70% prob… but when negative, it’s still almost 50%!!PreTest ProbAnderson et al.
34 Vaginitis symptoms cont. Question #2: Why perform microscopy?Agreement between clinician-read microscopy & culture is poor.Rapid commercial tests are here/around the cornerYou diagnose candidal vaginitis… you treat with fluconazole 150 mg x 1, but patient returns 1 week later with recurrence. What now?
35 Complicated Candidiasis CDC MMWR 2002;51:RR-6 Recurrent vulvovaginal candidiasisobtain vaginal culture to assess for non-albicans speciestreatment: topical therapy x 7-14 d; or fluconazole 150 mg, po, repeated in 3 dmaintenance (x 6 mo): clotrimazole 500 mg vag supp q week; fluconazole mg q week; itraconazole 400 mg q month or 100 mg q d.Severe vulvovaginitisNon-albicans vulvovaginitistreatment: d non-fluconazole azole drug; if recurs, 600 mg boric acid in gelatin capsule qd x 2 wks
36 Bacterial Vaginosis CDC MMWR 2002;51:RR-6 Criteria3 of 4 present:vaginal dischargeclue cellsvaginal pH > 4.5whiff test (fishy odor after 10% KOHManagement of Sex Partnersresponse to Rx and relapse are not affected by Rx of sex partnerClinical CriteriaTreatmentRecommended Regimen*metronidazole 500 mg bid x 7 d, ORmetronidazole gel 0.75%, one full applicator (5 g) iv, qd x 5 d, ORclindamycin cream 2%, one full applicator (5 g) iv qhs x 7dAlternative Regimensmetronidazole 2 g po x 1, ORclindamycin 300 mg po bid x 7 d, ORclindamycin ovules 100 g iv qhs x 3 d
37 Trichomoniasis CDC MMWR 2002;51:RR-6 CounselingManagement of Sex Partnerstreat sex partnersMicroscopy or CxTreatmentRecommended Regimen*metronidazole 2 g po x 1Alternative Regimensmetronidazole 500 mg bid x 7 d
38 SUMMARY UTI Typical Voiding Sx and no vaginitis... Empiric Rx Know local E.coli antibiotic-resistance ratesThreshold 20-30% sulfa-resistance to switch to FQ first-line…Consider STD testing, particularly in young, sexually active women (prevalence >=10%)… particularly for ChlamydiaNon-invasive testing is a reliable optionVaginitisCurdy discharge + vulvar inflamm/itching = YeastMalodor = non-yeastAbsence of malodor history may rule-out BV.