Disease Description (Causes and Symptoms)
- Definition: An acute bacterial infection of the upper urinary tract (kidneys and renal pelvis), usually caused by an ascending infection from the bladder or urethra, and rarely through the bloodstream.
- Main causes: Escherichia coli (E. coli) is the most common. Other gram-negative bacteria and antibiotic-resistant bacteria are also becoming more prevalent.
- Pathophysiology: Bacteria ascend to the renal pelvis through lower urinary tract infection, urinary reflux (vesicoureteral reflux), urinary tract obstruction, urethral catheters, and other mechanisms, causing inflammation. In severe cases, renal parenchymal damage, abscesses, and hematogenous spread (sepsis) may occur.
- Main symptoms: Fever, chills, flank or back pain (costovertebral angle tenderness), dysuria, urinary frequency, urinary urgency, a feeling of incomplete bladder emptying, nausea, vomiting, generalized malaise, and muscle pain. Children and older adults often have nonspecific symptoms, while high fever, loss of appetite, and vomiting are common.
Treatment Methods
- General principles: Mild, uncomplicated cases are treated as outpatients with oral antibiotics (initial empiric antibiotics → changed according to culture results). Severe or complicated cases (high fever, hypotension, signs of sepsis, dehydration, pregnancy, impaired renal function, urinary tract obstruction, etc.) require hospitalization for intravenous antibiotics and supportive care.
- Empiric antibiotics (selected according to local resistance rates):
- Mild outpatient treatment: Fluoroquinolones (levofloxacin, ciprofloxacin) or TMP-SMX (susceptibility testing is required); in some regions, beta-lactams (ampicillin-based or cephalosporin-based antibiotics) are used.
- Hospitalized or severe cases: Broad-spectrum intravenous antibiotics, such as third-generation cephalosporins (e.g., ceftriaxone), piperacillin-tazobactam, or carbapenems (when resistant bacteria are suspected).
- Treatment duration: Generally 7–14 days (7 days for mild cases; longer for severe or complicated cases). In cases such as a renal abscess, antibiotics may be needed for up to 4–6 weeks after drainage.
- Other treatment and supportive care: Adequate fluid intake, antipyretics and analgesics (such as acetaminophen), electrolyte and hemodynamic monitoring, and drainage in cases of urinary tract obstruction (ureteral stent or nephrostomy) may be necessary.
- Precautions and self-care
- Take antibiotics for the prescribed duration according to the doctor's instructions. Do not stop them on your own even if symptoms improve.
- Recent antibiotic use or high local resistance rates may affect the choice of empiric treatment until culture results are available.
- During pregnancy: Fluoroquinolones are contraindicated, and TMP-SMX is restricted during certain stages of pregnancy → beta-lactams are preferred.
- Risk of complications: Renal abscess, sepsis, and, in cases of recurrent infection, chronic renal damage (scarring) may occur. In children, the risk of renal damage increases if vesicoureteral reflux or urinary tract obstruction is present.
Checkpoints Before an Outpatient Visit (Including Items to Bring, Things to Confirm, and Sample Questions)
- Items to prepare/bring
- A list of currently used medications (including prescription drugs, over-the-counter medicines, and supplements) and a history of allergies
- Copies of recent urinalysis, culture, blood test, or imaging results (ultrasound/CT), if available
- A record of when symptoms began and how they have progressed (degree of fever, changes in urination, and whether vomiting or dehydration is present)
- Information about the possibility of pregnancy or current pregnancy, and a history of diabetes, immunosuppression, urinary tract abnormalities, or similar conditions
- Information about tests that may be performed during an outpatient visit
- Urinalysis (urine sediment), urine culture, and, if necessary, blood tests (including blood cultures), renal function tests, and abdominal or renal ultrasound (if complications are suspected)
- Precautions before an outpatient visit
- If you are already taking antibiotics, record the date you started taking them and the medication name. If you are taking them, test results (especially cultures) may be affected.
- Sample questions helpful for patients (including topics that are useful to ask the doctor in advance)
- Based on my symptoms, do I need to be hospitalized? When should I go to the emergency room?
- What side effects can I expect from the initially prescribed antibiotic, and what precautions should I take while taking it?
General Sample Questions to Ask the Doctor
- What are the main side effects of this antibiotic, and how should I respond if they occur?
- Do I need inpatient treatment in my case? What are the criteria for hospitalization?
- How long will treatment take? Will I need additional tests after treatment (follow-up urinalysis/imaging)?
- What lifestyle changes should I make to reduce the risk of recurrence?
- If I am pregnant, which antibiotics are safe?
- If the culture shows resistant bacteria, what will the next treatment plan be?
Disease-Specific Sample Questions
- If pregnant: "I am pregnant (or may be pregnant). Which antibiotics and treatment methods are safe and recommended?"
- If there is a urinary tract anatomical abnormality or recurrent infection: "I have recurrent pyelonephritis. Should I be tested for vesicoureteral reflux or urinary tract obstruction? Is surgical correction necessary?"