Podcast
Questions and Answers
What is the most common bacteria causing urinary tract infections?
What is the most common bacteria causing urinary tract infections?
Men are more likely to experience urinary tract infections than women.
Men are more likely to experience urinary tract infections than women.
False
Name one of the risk factors for urinary tract infection.
Name one of the risk factors for urinary tract infection.
Incomplete bladder emptying
At what age does the prevalence of UTI in women begin to increase?
At what age does the prevalence of UTI in women begin to increase?
Signup and view all the answers
The classic triad of symptoms for pyelonephritis includes loin pain, fever, and __________.
The classic triad of symptoms for pyelonephritis includes loin pain, fever, and __________.
Signup and view all the answers
What is the first choice antibiotic for lower urinary tract infections?
What is the first choice antibiotic for lower urinary tract infections?
Signup and view all the answers
Match the following urinary tract infection types with their descriptions:
Match the following urinary tract infection types with their descriptions:
Signup and view all the answers
What is the most common bacteria causing urinary tract infections?
What is the most common bacteria causing urinary tract infections?
Signup and view all the answers
UTIs are more common in men than in women.
UTIs are more common in men than in women.
Signup and view all the answers
What are the common clinical features of cystitis?
What are the common clinical features of cystitis?
Signup and view all the answers
The main risk factor for urinary tract infection is ______.
The main risk factor for urinary tract infection is ______.
Signup and view all the answers
Which gender has a higher prevalence of urinary tract infections?
Which gender has a higher prevalence of urinary tract infections?
Signup and view all the answers
What percentage of urinary tract infections exhibit resistance to trimethoprim?
What percentage of urinary tract infections exhibit resistance to trimethoprim?
Signup and view all the answers
Acute pyelonephritis typically presents with loin pain, fever, and tenderness over the kidneys.
Acute pyelonephritis typically presents with loin pain, fever, and tenderness over the kidneys.
Signup and view all the answers
Which investigation is standard for detecting urinary pathogens?
Which investigation is standard for detecting urinary pathogens?
Signup and view all the answers
The urinary tract is usually sterile except for the lower end of the ______.
The urinary tract is usually sterile except for the lower end of the ______.
Signup and view all the answers
What type of pyelonephritis may show gas formation in patients with diabetes?
What type of pyelonephritis may show gas formation in patients with diabetes?
Signup and view all the answers
Study Notes
Urinary Tract Infection
- The urinary tract is normally sterile, but the lower urethra is colonized by bacteria.
- The most common cause of urinary tract infection (UTI) is E.coli, which originates from the gastrointestinal tract.
- UTIs can present in several ways including asymptomatic bacteriuria, symptomatic acute urethritis, cystitis, acute pyelonephritis, acute prostatitis and septicemia.
Prevalence
- UTIs are more prevalent in women than men.
- Prevalence in women rises with age, starting at 3% at age 20 and increasing by 1% per decade.
- UTIs are uncommon in men, except for the first year of life and after 60 years old, when complications like bladder outflow obstruction can occur.
- The shorter urethra and absence of bactericidal prostatic secretions contribute to the higher prevalence in women.
Pathophysiology
- Urine is an excellent medium for bacterial growth.
- Urothelium in susceptible individuals can have more receptors, increasing the adherence of virulent E. coli strains.
Risk Factors
-
Incomplete bladder emptying:
- Bladder outflow obstruction (Benign prostatic hyperplasia, Prostate cancer, Urethral stricture, Vesico-ureteric reflux)
- Uterine prolapse
- Neurological problems: Multiple sclerosis, Spina bifida, Diabetic neuropathy leading to atonic bladder.
-
Foreign bodies:
- Urethral catheter or ureteric stent
- Urolithiasis
-
Loss of host defences:
- Atrophic urethritis & vaginitis in post-menopausal women.
- Diabetes mellitus.
Lower Urinary Tract Infection (UTI): Cystitis and Urethritis
-
Cystitis (inflammation of the bladder):
- Frequent urination and urgency.
- Burning pain during urination (dysuria).
- Suprapubic pain during and after voiding.
- Intense urge to urinate after voiding (strangury).
- Cloudy urine with a foul odor.
- Microscopic or visible hematuria.
-
Urethritis (inflammation of the urethra):
- Pain during urination (dysuria).
Upper Urinary Tract Infection (UTI): Pyelonephritis
-
Pyelonephritis (inflammation of the kidney):
- Classic triad of loin pain, fever, and tenderness over the kidneys.
- Rigors, vomiting, and hypotension.
- Loin pain, guarding, or tenderness.
- Possible hospitalisation.
- Can lead to papillary necrosis with the passage of renal tissue fragments, potentially causing ureteric obstruction and acute kidney injury (AKI).
Predisposing Factors for Pyelonephritis
- Diabetes mellitus
- Chronic urinary obstruction
- Analgesic nephropathy
- Sickle cell disease
Complications of Pyelonephritis
- Emphysematous pyelonephritis: Necrotizing form with gas formation, often seen in diabetic patients.
- Xanthogranulomatous pyelonephritis: Chronic infection resembling renal cell cancer, usually associated with obstruction.
Investigation of UTI
All Patients
- Dipstick urine estimation of nitrite, leucocyte esterase, and glucose.
- Microscopy of clean-catch midstream urine.
- Urine culture: Growth of urinary pathogen ≥ 100,000 cfu/ml urine (standard method).
Infants, children, and those with fever or complicated infection
- Full blood count, urea, electrolytes, creatinine
- Blood cultures
Pyelonephritis, males, children, and women with recurrent infections
- Renal tract ultrasound or CT.
- Pelvic examination in women.
- Rectal examination in men.
Continuing hematuria or suspicion of bladder lesions
- Cystoscopy
Common Urinary Tract Infection Organisms
-
Community-acquired UTI:
- E. coli (75% of infections)
- Proteus spp.
- Pseudomonas spp.
- Streptococci
- Staphylococcus epidermidis
-
Hospital-acquired UTI:
- E. coli is still the most common, but Klebsiella or streptococci are more prevalent.
Management of UTI
- Antibiotics are recommended for all confirmed UTIs.
- Start treatment while awaiting culture results.
Lower Urinary Tract Infection: Cystitis and Urethritis
- First-line treatment: Trimethoprim.
- Alternatives: Nitrofurantoin, quinolone antibiotics (ciprofloxacin, norfloxacin, levofloxacin).
- Duration: 3 days.
- Pregnancy Considerations: Penicillins and cephalosporins are safe, but avoid trimethoprim, sulphonamides, quinolones, and tetracyclines
Pyelonephritis, especially in seriously ill patients
- Intravenous antibiotics: Cephalosporins, quinolones, or gentamicin.
Urinary Tract Infections (UTI)
- The urinary tract is typically sterile, with bacteria only found in the lower urethra.
- The most common cause of UTIs is Escherichia coli (E. coli), originating from the gastrointestinal tract.
- UTIs present in various forms, including asymptomatic bacteriuria, symptomatic urethritis and cystitis, acute pyelonephritis, acute prostatitis, and septicemia.
Prevalence and Risk Factors
- UTIs are more common in women than men.
- The prevalence of UTIs in women increases with age, reaching around 3% at age 20 and increasing by about 1% every decade.
- In men, UTIs are less frequent except in infants and men over 60, where they can be associated with bladder outflow obstruction.
- The shorter urethra in women makes ascending infections easier.
- Risk factors for UTIs include:
- Incomplete bladder emptying:
- Bladder outflow obstruction (e.g., benign prostatic hyperplasia, prostate cancer, urethral stricture, vesicoureteric reflux)
- Uterine prolapse
- Neurological problems (e.g., multiple sclerosis, spina bifida, diabetic neuropathy) leading to atonic bladder
- Foreign bodies:
- Urethral catheters or ureteric stents
- Urolithiasis (stones in the urinary tract)
- Loss of host defenses:
- Atrophic urethritis and vaginitis in postmenopausal women
- Diabetes mellitus
- Incomplete bladder emptying:
Lower UTI (Cystitis and Urethritis)
- Symptoms include:
- Frequent urination and urgency
- Scalding pain during urination (dysuria)
- Suprapubic pain during and after urination
- Intense desire to urinate after voiding due to bladder wall spasm (strangury)
- Cloudy urine with unpleasant odor
- Microscopic or visible hematuria (blood in the urine)
Upper UTI (Pyelonephritis)
- Presents with a classic triad of:
- Loin pain
- Fever
- Tenderness over the kidneys
- Other symptoms can include:
- Rigors (shivering attacks)
- Vomiting
- Hypotension (low blood pressure)
- Loin pain, guarding, or tenderness, which may necessitate hospitalization
- Rare complications include:
- Papillary necrosis: fragments of renal tissue passed in the urine, potentially causing obstruction and leading to acute kidney injury
- Emphysematous pyelonephritis: a necrotizing form with gas formation, seen more commonly in diabetic patients.
- Xanthogranulomatous pyelonephritis: a chronic infection with characteristic foamy macrophages, often associated with obstruction and typically requiring nephrectomy (kidney removal).
Investigation
- All patients should undergo:
- Dipstick urine analysis for nitrite, leukocyte esterase, and glucose
- Microscopy of a clean-catch midstream urine sample
- Urine culture to determine bacterial growth (≥100,000 colony forming units/mL)
- Infants, children, and patients with fever or complicated infections require:
- Complete blood count, urea, electrolytes, and creatinine levels
- Blood cultures
- Patients with pyelonephritis, males, children, or women with recurrent infections may need:
- Renal tract ultrasound or CT scan
- Pelvic examination in women, rectal examination in men
- If hematuria persists or other bladder lesions are suspected, a cystoscopy (endoscopic examination of the bladder) may be indicated.
Typical Organisms
- Common organisms causing UTIs in the community include:
- E. coli (approximately 75% of UTIs)
- Proteus spp.
- Pseudomonas spp.
- Streptococci
- Staphylococcus epidermidis
- In hospitalized patients, E. coli remains common, but Klebsiella or streptococci may be more frequent.
Management
- Antibiotics are recommended for all confirmed UTIs.
- Treatment can begin while awaiting culture results.
- For lower UTI, preferred treatment options include:
- Trimethoprim (resistance rates between 10-40%)
- Nitrofurantoin
- Quinolone antibiotics (e.g., ciprofloxacin, norfloxacin, levofloxacin)
- Treatment usually lasts 3 days.
- Penicillins and cephalosporins are generally safe during pregnancy, but trimethoprim, sulfonamides, quinolones, and tetracyclines should be avoided.
- Pyelonephritis, especially in severely ill patients, may require intravenous therapy with cephalosporins, quinolones, or other appropriate antibiotics.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
This quiz covers the essential details about urinary tract infections (UTIs), including their causes, prevalence, and pathophysiology. It highlights the reasons why women are more affected and the role of bacteria like E.coli. Test your knowledge on the various forms UTI can present and the factors influencing their occurrence.
