what is acute pyelonephritis

3 min read 14-03-2025

Acute pyelonephritis is a serious bacterial infection of your kidney. It's a type of urinary tract infection (UTI) that spreads from your bladder or urethra to one or both of your kidneys. Left untreated, it can lead to serious complications, even life-threatening sepsis. Understanding its symptoms, causes, and treatment is crucial for prompt diagnosis and recovery.

Understanding the Symptoms of Acute Pyelonephritis

Recognizing the symptoms of acute pyelonephritis is vital for early intervention. These can vary in severity, but common signs include:

Fever and Chills: A high fever, often accompanied by shivering, is a hallmark symptom.
Flank Pain: This is a deep, aching pain in your lower back or side, usually on one side but potentially both.
Nausea and Vomiting: Gastrointestinal distress is frequent.
Frequent Urination: A strong urge to urinate, often with small amounts of urine.
Burning Sensation During Urination: Dysuria, or painful urination, is common.
Cloudy or Foul-Smelling Urine: Changes in urine appearance can indicate infection.
Fatigue and Weakness: General malaise and lethargy can accompany the infection.

Important Note: Some individuals, especially those with weakened immune systems, may experience less pronounced symptoms. Therefore, it’s essential to seek medical attention if you experience any combination of these symptoms. Don't delay treatment; early diagnosis is key.

What Causes Acute Pyelonephritis?

Acute pyelonephritis is primarily caused by bacteria, most commonly Escherichia coli (E. coli). These bacteria typically ascend from the lower urinary tract (bladder and urethra) to infect the kidneys. Several factors can increase your risk, including:

Urinary Tract Obstructions: Kidney stones, tumors, or other blockages can hinder urine flow, creating a breeding ground for bacteria.
Vesicoureteral Reflux (VUR): This condition causes urine to flow backward from the bladder to the ureters and kidneys.
Weakened Immune System: Individuals with compromised immune systems are more vulnerable to infections.
Pregnancy: Changes in the urinary tract during pregnancy increase susceptibility.
Diabetes: Poorly controlled blood sugar can increase the risk of infection.
Neurogenic Bladder: This condition involves nerve damage affecting bladder control.

How is Acute Pyelonephritis Diagnosed?

Your doctor will likely conduct a physical exam, checking for tenderness in your flank area. Diagnostic tests may include:

Urinalysis: Examining your urine sample under a microscope to detect bacteria, blood, and other abnormalities.
Urine Culture: Growing bacteria from your urine sample to identify the specific type and determine the most effective antibiotic.
Blood Tests: Checking for signs of infection, such as elevated white blood cell count.
Imaging Tests: Ultrasound, CT scan, or other imaging techniques may be used to visualize your kidneys and urinary tract to identify any obstructions or abnormalities.

Treating Acute Pyelonephritis

Treatment for acute pyelonephritis typically involves antibiotics, which are crucial for eradicating the infection. The specific antibiotic and duration of treatment will depend on the type of bacteria identified and the severity of the infection.

Antibiotics: Oral or intravenous antibiotics are often prescribed, depending on the severity of the infection. You'll likely need to complete the entire course of antibiotics, even if you feel better before finishing the medication.
Pain Management: Over-the-counter pain relievers, such as ibuprofen or acetaminophen, may help manage flank pain and fever.
Hydration: Drinking plenty of fluids helps flush out bacteria from your urinary tract. Avoid alcohol and caffeine, which can irritate the bladder.
Rest: Adequate rest is important to allow your body to fight the infection.

Hospitalization: In severe cases, hospitalization may be necessary for intravenous antibiotics and supportive care. This is especially crucial for individuals with severe symptoms, weakened immune systems, or complications.

Potential Complications of Untreated Acute Pyelonephritis

Ignoring or delaying treatment of acute pyelonephritis can lead to serious consequences, including:

Kidney Abscess: A localized collection of pus within the kidney.
Sepsis: A life-threatening condition caused by the body's overwhelming response to infection.
Chronic Kidney Disease: Long-term kidney damage.
Urosepsis: A severe bloodstream infection arising from a urinary tract infection.

Preventing Acute Pyelonephritis

While not always preventable, you can reduce your risk through these measures:

Drink Plenty of Fluids: This helps flush bacteria from your urinary tract.
Urinate Frequently: Don't hold your urine for extended periods.
Wipe From Front to Back: Proper hygiene after urination or bowel movements helps prevent bacteria from entering the urethra.
Practice Safe Sex: Sexually transmitted infections can increase the risk of UTIs.

Acute pyelonephritis is a serious infection requiring prompt medical attention. Recognizing the symptoms and seeking treatment promptly can prevent severe complications and ensure a full recovery. If you suspect you might have acute pyelonephritis, don't hesitate to consult your doctor immediately.