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Flashcards in Chapter 14 Deck (36):

Who is at risk for bacterial urinary tract infections?

Women (pregnancy and sexual activity increases risk)
Elderly (improper emptying of bladder)
Patients with comorbid conditions (diabetes), spinal cord injuries (improper emptying of bladder), catheters, genitaurinal tract abnormalities (tumor, stone)


What are the two different routes for pathogens to cause a UTI?

Ascending route up the urinary tract from the outside. E. coli
Heamatogenous from the blood to the kidney


What is bacteriuria?

The presence of bacteria in the urine (normally sterile), can be symptomatic (cloudy) or asymptomatic (only found by screening in lab)


When is treatment recommended fro asymptomatic bacteriuria (ASB)?

During pregnancy and prostate resection


What is the proper procedure when taking a urine sample?

Pee a little bit. Stop. Then pee in the cup to avoid getting skin contamination or tract flushing.


What are the two subtypes of a recurrent UTI?

Relapse is when you become infected by the same organism and same strain.
Reinfection is a 2nd subsequent infection from a different organism.


What does it mean to have an uncomplicated UTI?

Occuring in healthy, non-pregnant females
Readily treated with antibiotics


What does it mean to have a complicated UTI?

Occurring in either gender but is more difficult to treat due to underlying diseases, kidney stones, UT abnormalities or indwelling urinary catheters


What are some contributing factors to UTIs?

Length of urethra, sexual activity (females), uncircumcised male infants, blockage and catheterization (each day risk goes up 10%, allows bacteria to avoid urine, biofilm is more resistant)


What is urethritis? What are the symptoms?

Infection of the urethra
Symptoms are dysuria (burning pain on passing urine) and frequency


What is cystitis? What are the signs and symptoms?

Bladder infection, lower UTI
Symptoms: Dysuria, frequency, urgency, pain over bladder area
Signs: Bloody, cloudy urine and bad odour


What is acute urethral syndrome?

Same symptoms as cystitis but less CFU/ml
Pyuria (8 leukocytes/mm3 of uncentrifuged urine)


What is polynephritis? What are the two subtypes?
What are the symptoms?

The infection of the kidney and renal pelvis (acute and subclinical)
Fever, lower UTI symptoms


What is prostatitis?

Infection involving the prostate


What is cervicitis?

Inflammation of the cervix


What is the epidemiology of UTIs in pediatrics?

High morbidity
More likely to develop impaired renal function, hypertension, end-stage renal disease and complications during pregnancy as an adult


What is the epidemiology of UTIs in geriatrics?

Incidence in both men and women increases but more common in men (prostate enlargement, poorer bladder emptying)


What are the microbial virulence factors for pathogens in UTIs?

Adherence (bacterial adhesins), calculi formation, toxin and enzyme production (hemolysins, lipopolysaccharides), capsular polysaccharide, biofilms


How does the urinary tract prevent infection?

Flushing action of urinary flow, growth inhibitory properties of urine (low pH, osmolarity, high urea, organic acid concentrations), mucopolysaccharides, preventing reflux


How does the normal microflora of the urethra change with growing up?
Newborn to pre-pubertal

Newborns: Sterile
1-3 days: Staph aureus, enterococci, diptheroids
3 days-weeks: Lactobacillus acidophilius
Pre-pubertal: Micrococci, streptococci, coliforms, diphtheroids


What does the normal microflora of the urethra look like in pregnancy and post menopausal?

Similar to prepubertal microflora
Micrococci, streptococci, coliforms, diphtheroids


What does the normal microflora of the urethra look like in adulthood?

L. acidophilus, staph epidermidis, streptococci (alpha, non-hemolytic), E.coli, diphtheroids, yeasts


What are the gram negative bacilli that cause UTIs?

Fecal E.coli (uncomplicated)
MDR Enterobacteriaceae (hospital acquired)


How does duration of hospitalization and catheterization change the likely causative agents of a UTI?

Increased pseudomonas, proteus, klebsiella, acinetobacter and enterobacter
Decreased E. coli


What are the gram positive cocci that cause UTIs?

Enterococci (older men, UT manipulation, instrumentation)
Staph saprophyticus (symptomatic sexually active women


What are the gram positive bacilli that cause UTIs?

Diphtheroids, mycobacteria, Listeria monocytogenes
Bacillus (most likely contamination if in sample)


What are the fungi that cause UTIs?

Candiduria in hospitalized patients


What are the causative agents of cystitis?

E.coli, Klebsiella spp, other enterobacteriaceae, enterococci, CoNS


What are the causative agents of acute polynephritis?

Enterobacteriaceae, staphylococcus aureus


What are the causative agents of subclinical polynephritis?

CoNS, Candida spp, Mycobacterium spp, Mycoplasma hominis
Must be treated in pregnancy, young children, instrumentation, elderly and diabetics


How can a UTI be diagnosed?

From a midstream urine sample or right from bladder (avoids contamination, used to find anaerobic) and then microscopic examination


How can you tell if bacteria in urine is from infection or colonization when collected midstream?

1000 CFU/ml is infection


What could change the results of a urine sample?

If collected right from bladder, should have 0 CFU/ml
If on antibiotics, finding some CFU, could be a sign of resistant organisms
Drinking lots of water prior could dilute sample


How should a urine sample be stored?

Cultured within 1 hour of collection and stored at 4 degree for not more than 18 hours


How do we treat uncomplicated UTI (cystitis)?

May resolve spontaneously within 4 weeks
Antibiotics to reduce symptoms and ensure complete eradication, followup at end
Drink lots of fluids to facilitate flushing


How do we treat complicated UTI (pyelonephritis)?

Systemic IV treatment until symptoms subside with oral therapy afterwards
Should be >10 days to sterilize the kidney