Urinary Tract Infections Flashcards
Urine Characteristics
- Low pH
- Extremes in osmolality
- High urea and organic acid concentration
Flushing Mechanisms
Introduction of bacteria stimulates increased diuresis
Anti-Adherence Mechanisms
Coated epithelial cells of the bladder
Other Potential Factors
- Presence of lactobacillus in vaginal flora
- Estrogen levels
Classification
Uncomplicated
Nonpregnant female
Childbearing age (15-45 yo)
Otherwise healthy
No structural or functional abnormalities
Classification
Complicated
Pregnant females Males Children Diabetics Anatomical or structural abnormalities
Pylonephritis
Is a type of urinary tract infection (UTI) that generally begins in your urethra or bladder and travels to one or both of your kidneys. A kidney infection requires prompt medical attentio.
Infection of renal parenchyma
Signs and Symptoms
Uncomplicated Cystitis in Adults
Dysuria Polyuria Urgency Nocturia Suprapubic discomfort Gross hematuria
Signs and Symptoms
Pyelonephritis in Adults
Fever Nausea and vomiting Leukocytosis Dysuria, polyuria, urgency Flank pain Costovertebral angle (CVA) tenderness
Signs and Symptoms: Special Populations
Elderly
Altered mental status
Change in eating habits
GI symptoms
Lower UTI
Local symptoms: dysuria, frequency, urgency, suprapubic tenderness, hematuria (+/-)
Systemic symptoms: rarely present
Upper UTI
Local symptoms: lower UTI symptoms often NOT present
Systemic symptoms: fever, flank pain, abdominal pain, malaise, vomiting, chills, leukocytosis
Elderly
Altered mental status, change in eating habits, gastrointestinal symptoms
diagnosis of UTI
***Symptomatic Patients **
±
Positive Urine Culture
Urinalysis: Macroscopic
Color, appearance, and odor
Dipstick
Urinalysis: Macroscopic
Dipstick
Urine pH
Presence of glucose, blood, bilirubin, or protein
Leukocyte esterase
Detect presence of WBC
Nitrite test
Formed by bacteria that reduce nitrate to nitrite
Only members of the Enterobacteriaceae family
Urinalysis: Microscopic
Bacteriuria
≥ 10^5 CFU/mL –> indicative of UTI
≥ 10^2 CFU/mL –> diagnostic in presence of symptoms
Urinalysis: Microscopic
Pyuria
> 10 WBC/mm3
Nonspecific to UTI
Signifies presence of inflammation
Microscopic hematuria
Nonspecific to UTI
Urine Cultures
Gold standard for diagnosis Obtain prior to initiating antibiotics Identification and quantification Sensitivities Alter antibiotic treatment as needed
Gram-Negative
Escherichia coli Proteus species Klebsiella pneumoniae Enterobacter species Pseudomonas aeruginosa
Gram-Positive
Staphylococci species
Enterococcus species
Uncomplicated
Escherichia coli
•Most common: 80-90%
Uncomplicated
Staphylococcus saprophyticus
- Usually seen in young sexually active females
* Less common: 5-15%
Uncomplicated
Klebsiella pneumoniae, Proteus spp., Enterococcus spp., Citrobacter spp.
•Less common: 5-10%
Complicated
Escherichia coli
•Most common: <50%
Complicated
Enterococcus spp.
•Second most frequently isolated organism in hospitalized patients
Complicated
Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella pneumoniae, Proteus spp., Citrobacter spp., Acinetobacter spp.and Morganella spp.
•Less common
Causartive agents - Pearls
E. coli
Most common – responsible for 80-90% of cases
Causartive agents - Pearls
Proteus species
Produce urease – increases pH of urine
Causartive agents - Pearls
E. coli and K. pneumoniae
Common ESBL organisms