SHABNAM TEHRANI M.D., MPH ASSISTANT PROFESSOR OF INFECTIOUS DISEASESE &TROPICAL MEDICINE RESEARCH CENTER, SHAHID BEHESHTI UNIVERSITY OF MEDICAL

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1 URINARY TRACT INFECTION SHABNAM TEHRANI M.D., MPH ASSISTANT PROFESSOR OF INFECTIOUS DISEASESE &TROPICAL MEDICINE RESEARCH CENTER, SHAHID BEHESHTI UNIVERSITY OF MEDICAL SCIENCES

2 Definition inflammatory response of urothelium to bacterial invasion. Asymptomatic Bacteriuria : presence of significant bacteriuria in U/C but patient no symptom Cystitis: describe the syndrome involving dysuria, frequency, urgency, and occasionally suprapubictenderness tenderness. Pyelonephritis: describes the clinical i l syndrome characterized by flank pain, tenderness, or both, and fever, often associated with dysuria, urgency, and frequency

3 Complicated VS uncomplicated Uncomplicated UTI: UTI in healthy nonpregnant woman With structurally & functionally normal urinary W s uc u y & u c o y o u y tract.

4 Complicated UTI: Anatomical or funtional abnormality Male Foreign body ( calculi, catheter) Immunosuppresion Pregnant women Children Kidney transplant

5 Epidemiology urinary tract infections are a very common reason to seek health services Second most common infection following respiratory infections

6 The frequency of UTI in infants is about 1% to 2%. It is more common in boys during the first 3 months and thereafter occurs more often in girls. During gthe preschool years, UTI is much more common o in girls than in boys. In preschool boys, it is frequently associated with congenital urologic abnormalities Common in young females and uncommon in males under age 50

7 Up to 60% of the female population p will experience at least one symptomatic UTI at some time during their life. up to 10% of women in the United States have at least one episode of symptomatic infection each year.

8 Risk factors Female Age Low estrogen (menopause) Pregnancy D.M Previous UTI Stone GU malignancy Obstruction Voiding dysfunction Institutionalized elderly

9 risk factors for urinary infection in women Frequent sexual intercourse; a new sex partner Small urethra diaphragm use, especially with a spermicide; lack of urination after intercourse history of previous infection

10 Age-related Risk Factors for UTI Advanced Age Fecal incontinence/impaction Incomplete bladder emptying or neurogenic bladder Vaginal atrophy/estrogen deficiency Pelvic prolapse/cystocele Indwelling foley catheter or urinary catheterization or instrumentation procedures

11 Route of infection 1) Ascending: (Short urethra/reflux/impair ureteric peristalisis/pregnancy/obstruction/organism P pili) 2) Haematogenous: (bacteremia or endocarditis) Uncommon, Staph aureus/candida /salmonella ll 3) Lymphatics: Rarely in inflammatory bowel disease / reteroperitoneal abscess

12 PATHOGENESIS FEMALE SEX AND INTERCOURSE PREDISPOSES PREGNANCY: URETERAL TONE AND URETHRAL PERISTALSIS DECREASES OBSTRUCTION IN FREE FLOW OF URINE: TUMOR, STRICTURE, CALCULI AND BPH ETC. CATHETERISATION, URETHRAL DILATATION, CYSTOSCOPY

13 PATHOGENESIS The normal bladder is capable of clearing itself of organisms within 2 to 3 days of their introduction. Defense mechanisms (1) the elimination of bacteria by voiding (2) the antibacterial properties p of urine and its constituents (3) the intrinsic mucosal bladder defense mechanisms (4) an acid vaginal environment (female) (5) )p prostatic secretions (male)

14 ASCENDING INFECTION The ability of host defense Urinary tract mucosal cells damaged The power of bacterial adhesions(toxicity) organisms urethra,periurethral tissues bladder ureters renal pelvis renal medulla

15 PATHOGENESIS hematogenous route: Because the kidneys receive 20% to 25% of the cardiac output, any microorganism that reaches the bloodstream can be delivered to the kidneys. The major causes of hematogenous infection are S. aureus, Salmonella species, and Candida species.

16 Microbiology More than 95% of uncomplicated UTIs are caused by a single bacterial species Faecal-drived bacteria E.Coli, G-ve baccillus, (up to 85 % ) Staphylococcus saprophyticus, gram-positive organism causes 10 15% Enterococ faecalis

17 Catheter-associated UTI s: caused by ygram-negative g bacteria: Proteus, Klebsiella, Seratia, Pseudomonas Fungi (particularly Candida spp.) occur in patients with indwelling catheters who are receiving antimicrobial therapy

18 Clinical manifestation General manifestations of cystitis: Dysuria Frequency urgency Urine has foul odor, cloudy, bloody (hematuria) Suprapubic pain and tenderness

19 The classic clinical manifestations of pyelonephritis p include : fever (sometimes with chills) flank pain frequently lower tract symptoms (e.g., frequency, urgency, and dysuria)

20 Severe pain with radiation into the groin is rare in acute pyelonephritis per se and suggests the presence of a renal calculus. Patients with UTIs in the presence of an indwelling urinary catheter usually have no lower tract symptoms, but flank pain or fever may occur.

21 Symptoms of UTI are frequently difficult to elicit in older adults ( presence of dementia, indwelling urinary catheters, and the atypical symptoms). Fever is generally absent with cystitis and, if present, should suggest upper tract infection.

22 Diagnosis

23 Diagnostic Tests a. Urinalysis: assess pyuria, bacteria, blood cells in urine; Bacterial count >100, /ml lindicative i of infection b. Rapid idt tests t for bacteria in urine 1. Nitrite dipstick (turning pink = presence of bacteria) 2. Leukocyte esterase test (identifies WBC in urine) c. Gram stain of urine: identify by shape and characteristic (gram positive or negative)

24 Dipstick leukocyte esteraseof MSU: WBC ( pyuria ) 75%to96% sensitivity infection Nitrite testing: Bacteriuria. + test infection infection 94% to 98% specificity Other causes of pyuria

25 The dipstick leukocyte esterase test is a rapid screening test for detecting pyuria It should be emphasized that the finding of pyuria is nonspecific, and patients with pyuria may or may not have infection

26 WBC casts in the presence of an acute infectious process are strong evidence for pyelonephritis, WBC casts can also be seen in renal ldisease in the absence of infection. Proteinuria is a common although not universal finding in UTI. Most patients with UTI excrete less than 2 g of protein/24 hr.

27 Urine Culture: Significant bacteriuria Acceptable methods for urine collection include Midstream clean catch : (preferred) Catheterization: In patients unable to cooperate, such as those with an altered sensorium or those who are unable to void for neurologic or urologic suprapubic aspiration:premature infants, neonates,

28 Indications for further investigations in UTI. Symptoms of Upper UTI. Recurrent UTI. Pregnancy Unusal infecting organism ( proteus suggest infection stone) KUB Ultrasound IVU CT

29 Management Hydration: produces rapid dilution of the bacteria and removal of finfected urine by frequent bladder emptying. Analgesics:Urinary analgesics such as phenazopyridine hydrochloride have little place in the routine management of symptomatic infections. Th d i f UTI ll d idl t The dysuria of UTI usually responds rapidly to antibacterial therapy and requires no local analgesia.

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34 Response to therapy Cure Persistance recurrent

35 Bacteriologic Relapse: This usually occurs within 1 to 2 weeks after the cessation of chemotherapy and is often indicates that the infecting microorganism i has persisted din the urinary tract tduring therapy.(renal infection, structural abnormalities of the urinary tract, or chronic bacterial prostatitis) Reinfection

36 Reinfection: Patients with symptomatic reinfections can generally be divided into two groups: (1) those who have relatively infrequent reinfections, perhaps p only once every 2 or 3 years to several times a year (2) those who develop frequent reinfections.these are usually young and middle-aged sexually active women who have recurrent cystitis

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39 Asymptomatic bacteriuria screening for or treatment of asymptomatic bacteriuria is not recommended for any group of adult patients, including diabetics, except in renal transplant patients during pregnancy those who are to undergo traumatic genitourinary procedures associated with mucosal bleeding, such as transurethral prostatectomy and percutaneous lithotomy

40 UTI in pregnancy During gpregnancy, there is dilation of the ureters and renal pelves, with markedly decreased ureteral peristalsis. The microbiologic picture of bacteriuria during gestation is similar to that seen in nonpregnant women. The prevalence of asymptomatic bacteriuria in pregnancy ranges from 4% to 7%.

41 The development of symptomatic pyelonephritis late in pregnancy is usually an expression of asymptomatic bacteriuria that was present earlier in the pregnancy. About 20% to 40% of the patients with untreated bacteriuria early in gestation develop acute symptomatic pyelonephritis later in pregnancy. In contrast, less than 1% of patients whose urine is uninfected early in gestation develop acute infection

42 Treatment with an appropriate antimicrobial agent is recommended for all pregnant patients found to have significant bacteriuria. All women should be screened in the first and, ideally, third trimesters of pregnancy The goal of therapy is to maintain sterile urine The goal of therapy is to maintain sterile urine throughout gestation and thereby avoid the complications associated with UTI during pregnancy.

43 In the treatment of asymptomatic bacteriuria and cystitis, treatment modalities include single-dose fosfomycin 3 g or cephalexin 500 mg four times a day for 3 to 5 days, or a 7-day course of nitrofurantoin. Trimethoprim-sulfamethoxazole for 3 days

44 Acute pyelonephritis p in pregnancy is treated vigorously initially with parenteral antibiotics,such as third-generation cephalosporins for 14 days In selected patients with mild disease a trial of oral p antibiotic therapy with cefixime can be given for 14 days with close follow-up.

45 U/C should be obtained 1 to 2 weeks after discontinuing therapy and at regular intervals (e.g., monthly) for the remainder of gestation because recurrence is common (20%to30%) 30%). Patients with a prepregnancy history of UTI should undergo repeated screening during pregnancy If relapses or multiple reinfections occur during pregnancy,an imaging evaluation should be considered postpartum

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