UTI’s Flashcards
What are UTI’s?
Urinary tract infections (UTIs) are infections of the bladder, urethra, ureters, or kidneys that are most commonly caused by bacteria, especially E. coli.
What is the aetiology of UTI’s?
Bacteria - infection ascends from urethra to bladder. Causative agents - E.coli, staph aureus, klebsiella pneumonia, nosocomial bacteria.
Viruses - immunocompromised patients and children especially susceptible. Causative agents include - adenovirus, cytomegalovirus, and BK virus.
Fungi - rare (usually Candida species)
What are the predisposing factors?
Host dependent factors - structural opt functional abnormalities of the urinary tract
Female sex
Pregnancy
Post menopause
Chronic constipation
Prior conditions - previous UTI, history of kidney surgery, iummunosuppreression, diabetes mellitus
Sexual intercourse
Catheter associated UTI
What is the classification of UTI’s?
Look at amboss notes on UTI
What are the clinical features of a UTI?
Clinical features of lower UTI [19][20]
Irritative lower urinary tract symptoms (LUTS)
Increased urinary frequency
Urinary urgency
Dysuria
Hematuria
Suprapubic tenderness
Clinical features of upper UTI (pyelonephritis) [21]
Symptoms of lower UTI
Fever
Flank pain
Costovertebral angle tenderness
Fatigue/malaise
Nausea and vomiting
See “Clinical features” in “Pyelonephritis.”
Additional features (special patient groups) [19]
Male individuals: pain in the prostatic/perineal area
Children: See “Clinical features of pediatric UTI.”
Older adults: delirium/acute confusion
What is the diagnosis for a UTI?
For symptomatic, uncomplicated UTI’s, can be diagnosed clinically
For others, urinalysis is the most important initial test
What is the diagnosis for an uncomplicated lower UTI in women?
Perform urinalysis using urine dip stick test and or microscopy - positive urinalysis (proof of pyuria and bacteriuria): initiate treatment. Negative urinalysis but persisting suspicion: obtain urine culture
what is the diagnosis for a complicated UTI in women?
Obtain urinalysis and urine culture
What is the diagnosis for a lower UTI in men?
Obtain urinalysis and urine culture
First febrile UTI - perform CT or ultrasound of urinary tract
Consider referral to urology (in case of unclear diagnosis eg Hematuria)
What are the typical urinalysis findings for a UTI?
Pyuria - presence of WBC’s in urine
Positive leukocyte esterase - an enzyme produced by WBC
More than or equal to 5WBC/HPF (HIGH POWER FIELD) or more than or equal to 8-10WBC/mm cubed
Bacteriuria - presence of bacteria in urine - positive urinary nitrites, direct visualisation by gram stain
Other findings - leukocyte casts may indicate pyelonephritis
Micro or macroscopic Hematuria may be present
Alkaline urine (pH>8) and struvite crystals in sediment
Presence of squamous epithelial cells can b a sign of contamination
What are some indications for a urine culture?
Suspicion for complicated UTI or healthcare-associated UTI
Suspicion for pyelonephritis or urosepsis
Suspicion for uncomplicated cystitis with either of the following:
History of recurrent UTIs [10]
Equivocal urinalysis
Atypical symptoms
Concern for multiresistant pathogens, e.g., due to recent antibiotic use [15]
Age ≥ 65 years [28]
Follow-up cultures for test of cure in the following cases:
Nonresolving symptoms despite antibiotic treatment
Anatomic or functional abnormalities of the urinary tract
Continued pathological findings on urinalysis
When is a urine culture positive for a UTI?
Bacteriuria - ≥ 10^5CFU/mL in a clean-catch specimen
Any organisms in a specimen obtained by suprapubic aspiration
What are sine additional diagnostics for a UTI?
Pregnancy test - for women of child bearing age
Testing for STI’s
Imaging - not generally indicated but can do CT abdomen and pelvis with or without IV contrast (indicated in urinary tract obstruction)
What is the DD for UTI?
Interstitial cystitis
Asymptomatic bacteriuria
What is the general treatment for a UTI?
Antibiotic therapy for symptomatic UTI e
