bladder with fever

Overview

A bladder infection with fever often means the infection has moved from the bladder to the kidneys, causing a more serious condition called pyelonephritis. The bladder is part of your urinary tract that stores urine. When bacteria get into the bladder, they can cause an infection. If you also have a fever, it is a sign that your body is fighting a more widespread infection.

Bladder infections are very common, especially in women. However, having a fever along with bladder symptoms is less common and may signal that the infection has spread to the kidneys.

Anyone can get a bladder infection, but they are more common in women, older adults, people with weakened immune systems, and those who use a urinary catheter.

Symptoms

Common symptoms

• Frequent urge to urinate
• Burning pain when urinating
• Cloudy or strong-smelling urine
• Lower belly pain or pressure
• Feeling tired or unwell

Symptoms in children

• Fever (often the main sign)
• Irritability or fussiness
• Poor feeding or vomiting
• Strong-smelling urine
• Crying when urinating

Symptoms in older adults

• Confusion or sudden change in behavior
• Fever without typical urinary symptoms
• Agitation or restlessness
• Loss of appetite
• Incontinence or worsening of existing incontinence

Causes

Main causes

• Bacteria (most often Escherichia coli or E. coli) entering the bladder through the urethra
• The infection then moving up to the kidneys, causing fever

Risk factors

• Being female (shorter urethra makes it easier for bacteria to reach the bladder)
• Sexual activity
• Menopause (changes in the urinary tract increase risk)
• Using a urinary catheter
• Conditions that block the flow of urine, such as kidney stones or an enlarged prostate
• Weakened immune system (due to diabetes, chemotherapy, or other reasons)

When to see a doctor

See a doctor urgently if:

• If you have a fever along with any bladder symptoms
• If you have back pain, chills, or are vomiting
• If you are pregnant and have bladder symptoms
• If you have a weakened immune system

Book a routine appointment if:

• If you have mild bladder symptoms without fever, you can call your doctor for advice within a day or two
• If you have frequent bladder infections (more than 2 in 6 months), see your doctor for an evaluation

Diagnosis

Your doctor will ask about your symptoms and medical history. They will typically order a urine test to check for infection.

Tests that may be done

• Urine dipstick test (a quick test that looks for signs of infection)
• Urine culture (takes a few days to confirm which bacteria are present and which antibiotics will work)
• Blood tests if a kidney infection is suspected
• Imaging tests (like an ultrasound or CT scan) if you have frequent infections or there are concerns about blockages

What to expect at your appointment

You will be asked to provide a clean-catch urine sample (you clean your genital area before collecting urine midstream). The test is painless. If you have a fever, the doctor may also check your temperature and vital signs. In most cases, you will start treatment before the culture results are back.

Treatment

Treatment focuses on clearing the infection and relieving symptoms. Most bladder infections with fever require antibiotics to prevent the infection from spreading further.

Self-care at home

• Drink plenty of water to help flush bacteria out of your bladder
• Rest to help your body fight the infection
• Use a heating pad on your lower belly or back for pain relief
• Avoid drinks that can irritate your bladder, like coffee, alcohol, and acidic fruit juices
• Urinate often and completely empty your bladder each time

Medical treatments

A doctor will prescribe a course of antibiotics to kill the bacteria. It is important to take the full course as directed, even if you start feeling better. For severe infections with high fever or vomiting, you may need antibiotics through a vein (intravenously) in a hospital.

When is surgery considered?

Surgery is rarely needed for a simple bladder infection. It may be required if there is a blockage (like a kidney stone or enlarged prostate) that is causing repeated infections, or if an abscess forms in the kidney.

Living with this condition

While you are recovering, take it easy and follow your treatment plan. Monitor your symptoms and watch for any warning signs that the infection is getting worse. Finish all your antibiotics even if you feel better.

Lifestyle tips

• Urinate when you feel the urge – holding it in can allow bacteria to multiply
• Wipe from front to back after using the toilet to prevent bacteria from entering the urethra
• Stay well hydrated every day
• Avoid using spermicidal products or diaphragms if you get frequent infections

Diet and exercise

A balanced diet helps support your immune system. Drinking cranberry juice may reduce the risk of future infections, but it is not a treatment for an active infection. Gentle exercise like walking can help you feel better, but rest when you are tired.

Mental health and emotional wellbeing

Recurrent bladder infections can be frustrating and worrying. It is normal to feel anxious or stressed. Talk to your doctor about strategies to reduce recurrence and manage any anxiety.

Prevention

You can reduce your risk of bladder infections by staying well hydrated, urinating after sexual activity, wiping front to back, and avoiding unnecessary use of catheters. For some people, low-dose antibiotics may be prescribed to prevent frequent infections – talk to your doctor if this is a concern.

Complications

If left untreated

• Kidney infection (pyelonephritis), which can cause permanent kidney damage
• Kidney abscess (a pocket of pus in the kidney)
• Sepsis (a life-threatening infection that spreads through the blood)
• In pregnant women, an increased risk of preterm labor or low birth weight

Long-term outlook

With prompt and proper treatment, most people recover completely from a bladder infection with fever. The outlook is excellent. Even serious kidney infections can be treated successfully with antibiotics, especially when caught early. If you have frequent infections, your doctor can help you find ways to prevent them.

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