APPROACH TO URINARY INFECTION IN PRIMARY CARE

ASSOC PROF HÜLYA AKAN,MD

DEPARTMENT OF FAMILY MEDICINE

Objectives

• At the end of this lesson students should be able to explain approach to

- Acute uncomplicated lower tract infection in women

- Recurrent lower tract infection in women- Acute upper tract infection (pyelonephritis) in

women- UTIs in men- UTI s in children

• The urinary tract is comprised of the kidneys, ureters, bladder, and urethra

• A urinary tract infection (UTI) is an infection caused by pathogenic organisms (for example, bacteria, fungi, or parasites) in any of the structures that comprise the urinary tract.

• Dysuria is the most prominent symptom and accounts for 3% of primary care office visits

• Approach to urinary infection differs according to age, sex and underlying diseases

• Acute uncomplicated lower tract infection in women

• Recurrent lower tract infection in women

• Acute upper tract infection (pyelonephritis) in women

• UTIs in men, children and geriatric population

• The most common causes of UTI infections (about 80% to 90%) are Escherichia coli bacterial strains that usually inhabit the colon.

• Klebsiella, Pseudomonas, Enterobacter, Proteus, Staphylococcus, Mycoplasma, Chlamydia, Serratia and Neisseria

• Some parasites (Trichomonas, Schistosoma) also may cause UTIs

Differential Diagnosis

• Vaginal atrophy

• Vaginitis

• Urethritis

• Interstitial cystitis

• Prostatitis

• Urethritis

Risk factors

• %10-20% of women have epithelium makes easy adherence of m.o.

• Colonization of vagina – use of contaceptive cream-jelly, nonoxynol-9

• Barrier use• Shorter distance between urethra and anus-

sexual intercourse• Fecal incontinence• Stasis of baldder

Risk factors of pyelonephritis

• Recurrent urinary tract infection

• Diabetes mellitus

• Recent incontinence

• New sexual partners

• Use of spermicide

• Mother with history of UTI

History

• Urinary frequency

• Dysuria

• Nocturia

• Suprapubic discomfort

• Urgency

• Malodorous urine

Probability of symptoms

•Dysuria+nocturia: %65

•Malodorus urine and nocturia or urgency or recurrence of symptoms fallowing UTI: 90%

•Vaginal complaints, external dysuria: STI /vaginitis

• Upper urinary infection (pyelonephritis)

Fever

Chills

Flank pain

Abdominal pain

Vomitting

Physical Examination

• Vital signs

• Palpation of mid and lower abdomen

• Percussion of flanks

• Genital examination (prostatitis, vaginitis)

Red Flags for a complicated Infection

• Male gender• Infant or geriatric age• Symptoms more than 7 days• Immunosuppressive condition• Diabetes mellitus• Episode of acute pyelonephritis within the past

year• Known anatomic abnormality• Fever• Flank pain or tenderness

Laboratory Tests: Collecting specimen

• Midstream urine: First few seconds of urine is not collected

• Catheterization in infants and very young

• Plastic bag collection

Urinanalysis

Dry reagent test strip (dipstick)• Leukocyte esterase: Detects presence of

esterase from WBC. False positive: chlamydial infection, high urine pH, high levels of urine glucose, certain drugs

• Nitrite: Dietary nitrates are excreted into the urine and converted to nitrit by bacteria

False negative: Gram positive ones and Pseudomonas don’t convert nitrate to nitrite, E. Coli need sometime to convert and vegeterians

• Leucocyte esterase + nitrite: both positive and both negative is better predictor of infection presence or absence

• Blood:Peroxidase like activity

False positive: Myoglobin, peroxidase producing bacteria

Direct microscopy:• Centrifuge 10 ml freshly

voided urine, decanting the urine than resuspending the sediment

• Leukocyte:High-power field (x 400) 5 or more

• Bacteria: 10 or more ; if no bacteria rule out

• White cell casts

Urine Culture• Not cost-effective in routine care• Do it:- Children, men, geriatric population- Patients with red flags

- Younger women: Risk of upper tract infection

- Infection with bacteria not likely respond firt line antibiotics

Management: Acute uncomplicated lower tract infection in women

• Telephone directed• Ampiric antibiotic treatment: 3 days or 7 days

regimen

- Trimethoprim/sufamethoxazole

- Nitrafurantoin (7 days)

- Fluoroquinolone (e.g.ciprofloxacine)• Occult pyelonephritis: 7 days regimen• Phenazopyridine analgesia for severe dysuria

Management: Acute uncomplicated lower tract infection in women

• Recurrent infection: Urine culture and treat in the same way

• Prevention: • Patient initiated treatment• Unsweetened cranberry juice• Increasing fluid intake• 3 or more a year related STI: single dose

antibiotic after intercourse• Behavioral advices( not using pantyhose, wiping

font to back, postcoital voiding) have not been proven effective.

Acute Pyelonephritis inYounger Women

• Women who are medically stable and maintaining hydration with oral intake: Can be treated as outpatients

• Women who, because of severity of infection or underlying disability, are not medically stable or unable to take oral fluids or medications: Refer for hospitilization

• Women who have been infection complicated by abcess or obstruction, regardless of ability to take fluids by mouth

Adult Men with UTIs

• Differentiate lower or upper UTIs

• Differentiate prostatitis and urethritis

• Treat as complicated UTIs: - Order urine culture

pretreatment - First line usually

floroquinalone 14 days• After second infection or first

episode of pyelonephritis: Imaging for anatomic abnormality or nephrolithiazis

UTIs in Older Adults

• Atypic symptoms: Mental status change, tachpnea, tachycardia, fever, gait instability, or falls

• Pretreatment urine culture• 3 days regimen acceptable but 7-14 days are

prefered• Frequent relapses: Search for nephrolithiazis or

urinary retention• Elder women: Local estrogen decrease

repeating gram negative organisms

UTIs in Children

• Girls: 5-8 %• Boys: 1-2 %• Noncircumsized v

circumsized• Young children:

perineal colonization• Older children: stasis• Vesicoureteral reflux:

30-50 %

• Vesicoureteral reflux: 30-50 %

• Recurrent infection and renal scarring

• First year of life: unexplained fever consider UTIs

• Neonates: Late-onset jaundice, Poor weight gain, Irritability, Hypothermia

• Infants: Diarrrhea , vomiting, failure to thrive

• School children: Back pain, abdominal pain, incontinence

• Urinanalysis has limited sensitivity in young children; Urine culture routinely

• Older children dipstick and urine microscopy have similar sensitivity and specifity as in adults

• Older than 3 mo: 3 days antibiotic regimen if no systemic signs

TMP/SMXAmoxicillin/clavunateNitrafurantoinThird generation cephalosporins• Younger than 3 mo: refer for hospitilization;

treated with parenteral antibiotics• Urine culture after cpmpletion of treatment to

confirm successful treatment

Imaging studies to detect anatomic or functional abnormalities:

• < 2 yrs

• > 2 yrs with recurrent infections

• >2 yrs with single episode of acute pyelonephritis