Infecção do trato urinário (ITU) - Aula MR

Summary

Urinary tract infections (UTIs) are more common in women due to anatomical factors and sexual activity. The main cause is *Escherichia coli*, which can lead to asymptomatic bacteriuria, cystitis (bladder infection), or pyelonephritis (kidney infection). Asymptomatic bacteriuria is treated in high-risk groups like pregnant women and those undergoing urological procedures. Cystitis is typically managed with oral antibiotics, while pyelonephritis may require intravenous treatment, especially in complicated cases. Early detection and proper treatment are essential to prevent complications like kidney damage or preterm birth. Diagnosis involves urine cultures and analysis, and treatment duration varies based on infection severity.

Takeaways

• 😀 UTIs are more common in women than men due to anatomical differences, such as a shorter urethra and its proximity to the anal region.
• 😀 The main bacterial agent responsible for urinary tract infections is *Escherichia coli*, which adheres to the urological epithelium and ascends into the urinary tract.
• 😀 Asymptomatic bacteriuria is the presence of bacteria in the urine without any symptoms, typically requiring treatment only in specific groups such as pregnant women and patients undergoing urological procedures.
• 😀 Cystitis (bladder infection) is characterized by symptoms like painful urination (dysuria), increased frequency (pollakiuria), and urgency, but it does not cause systemic symptoms like fever.
• 😀 Pyelonephritis (kidney infection) is more severe and causes symptoms like fever, flank pain, and chills, and may require more aggressive treatment.
• 😀 Pregnant women with asymptomatic bacteriuria must be treated to prevent complications such as preterm birth, making routine urine cultures part of prenatal care.
• 😀 Urinary tract infections in patients undergoing invasive urological procedures or those with recent renal transplants should be treated to prevent bacteremia or further complications.
• 😀 Diagnosis of UTIs can involve urinalysis and urine cultures. For cystitis, a urine culture is not always necessary unless symptoms persist, while pyelonephritis requires a more thorough workup with urine culture and imaging if needed.
• 😀 Treatment for cystitis can include antibiotics like fosfomycin (single dose), nitrofurantoin (5-7 days), or beta-lactams (7 days).
• 😀 Severe or complicated pyelonephritis may require hospitalization and intravenous antibiotics such as piperacillin-tazobactam, and treatment may last up to 21 days depending on the case.

Q & A

Why are urinary tract infections (UTIs) more common in women than men?

UTIs are more common in women due to anatomical differences. Women have a shorter urethra, which is closer to the anus, making it easier for bacteria to enter the urinary tract compared to men, whose longer urethra makes bacterial entry more difficult.

What are the primary risk factors for UTIs in women?

The main risk factors for UTIs in women include sexual activity, pregnancy (especially asymptomatic bacteriuria), undergoing invasive urological procedures, and recent kidney transplants.

What is asymptomatic bacteriuria and who needs treatment for it?

Asymptomatic bacteriuria refers to the presence of bacteria in the urine without symptoms. Treatment is necessary for pregnant women, patients undergoing urological procedures, and those with recent kidney transplants.

How is asymptomatic bacteriuria diagnosed?

Asymptomatic bacteriuria is diagnosed through a urine culture showing at least 100,000 colony-forming units per milliliter (CFU/mL) of bacteria in the urine. In patients with a catheter, a lower threshold of 10^2 CFU/mL may be used.

What are the typical symptoms of cystitis (lower UTI)?

Symptoms of cystitis include painful urination (dysuria), frequent urination (pollakiuria), and lower abdominal discomfort. Unlike pyelonephritis, cystitis does not cause systemic symptoms like fever.

How do you diagnose cystitis in a patient?

Cystitis is diagnosed based on clinical symptoms and a urine analysis that shows signs like pyuria (pus in the urine), positive nitrites, or the presence of bacteria. A urine culture is not always required if clinical diagnosis is clear.

What are the treatment options for cystitis?

Cystitis can be treated with antibiotics such as fosfomycin (single dose), nitrofurantoin (for 7 days), or beta-lactams (e.g., amoxicillin) for 7 days. Empiric treatment can begin without a urine culture if symptoms strongly suggest cystitis.

What distinguishes pyelonephritis from cystitis?

Pyelonephritis is a more serious upper UTI that causes fever, flank pain, chills, and can lead to sepsis. Cystitis, on the other hand, is a lower UTI with symptoms localized to the bladder without systemic symptoms like fever.

What is the treatment for pyelonephritis?

Treatment for pyelonephritis depends on whether it is complicated or uncomplicated. Uncomplicated cases can be treated with oral antibiotics like ciprofloxacin or levofloxacin for 7 days. Complicated cases require hospitalization and intravenous antibiotics, such as piperacillin-tazobactam, for 14 days.

When is imaging necessary in a patient with pyelonephritis?

Imaging is necessary in cases of complicated pyelonephritis, especially if there is suspicion of abscesses, renal stones, or structural abnormalities. A CT scan with contrast is the gold standard for diagnosing these complications.