Signs and Symptoms of a Urinary Tract Infection (UTI)

A urinary tract infection (UTI) is a bacterial infection that affects any part of the urinary system— including the bladder, kidneys, ureters, and urethra. You may feel a sudden and strong urge to urinate only for a small amount of urine to come out, make frequent trips to the bathroom, and experience pain and burning while urinating. If the infection moves into the kidneys then fever, chills, severe pain, nausea, and vomiting can occur.

UTIs are among the most common infections, affecting millions of people of all ages worldwide each year. Anyone can get a UTI, but they are more common in women than men—about 60% of women will experience at least one UTI in their lifetime.

Common Symptoms 

Symptoms of a urinary tract infection depend on the part of the urinary system affected. The urinary tract is divided into two distinct parts: the lower and upper urinary tract.

• Lower urinary tract: The bladder and urethra (the tube that carries urine out of the body). An infection affecting this part of the urinary system is called a bladder infection (cystitis).
• Upper urinary tract: The kidneys and ureters (ducts that move urine from the kidneys to the bladder). An infection in the upper urinary tract is a kidney infection (pyelonephritis).
  

Lower Urinary Tract Infection (Bladder Infection) Symptoms 

Lower urinary tract infections affect the bladder or urethra and are the most common type of UTI. A bladder infection, or cystitis, occurs when bacteria normally found in the bowel enter the urethra and travel to the bladder, causing an infection.

Symptoms usually come on suddenly and can include:

• Pain or burning when urinating
• Frequent urination 
• A strong urge to urinate, even when only a small amount of urine comes out
• Cloudy or reddish-colored urine 
• Smelly urine 
• Cramping or pain in your lower abdomen, back, or pelvic area

Upper Urinary Tract Infection (Kidney Infection) Symptoms 

If left untreated, a bladder infection can move up to the kidneys. A kidney infection, or pyelonephritis, is a serious condition that requires immediate medical attention. Kidney infection symptoms can include:

• Fever
• Chills
• Nausea
• Vomiting 
• Cloudy, dark, or bloody urine
• Smelly urine
• Frequent urination
• Pain when urinating 
• Pain in the back, side, or groin 

Older adults (ages 65+) may not have typical kidney infection symptoms. Instead, they may seem confused, have jumbled speech, or experience hallucinations (seeing things that are not there). 

Symptoms in Children 

Urinary tract infections are common in children, especially in males younger than 12 months and females ages 4 and under. UTI symptoms in children vary, depending on the age of the child. 

UTI symptoms in children ages 2 and under include: 

• Fever higher than 100.4°F 
• Irritability 
• Fussiness 
  

UTI symptoms in children ages 3 and older include: 

• Pain or burning during urination
• Frequent urination
• Bedwetting or daytime wetting (after potty training) 
• Strong-smelling urine
• Cloudy or bloody urine
• Pain or discomfort in the lower abdomen or flanks (sides of the back)
• Fever higher than 100.4°F 

When to See a Healthcare Provider 

UTI symptoms can range from mild to severe. It is important to see a healthcare provider right away, especially if your symptoms worsen or persist for 3-4 days, or if you get frequent UTIs. Most UTIs are treated with antibiotics that help to ease symptoms within a few days of treatment.

Certain UTI symptoms can indicate a more serious infection and warrant immediate emergency evaluation. Seek prompt medical attention if you have the following symptoms:

• High fever 
• Blood in your urine
• Pain in your lower abdomen or back 
• Lethargy
• Confusion 
• Chills
• Nausea or vomiting 

If you have been treated for a UTI and your symptoms return after you finish taking antibiotics, call your healthcare provider. UTI recurrences are common; nearly 30% of women will have a recurrent UTI within six months after an initial UTI.

A Quick Review 

A urinary tract infection (UTI) can affect any part of the urinary system, including the bladder, urethra, kidney, and ureters. Anyone can get a UTI, but they are most common in women. Common UTI symptoms include pain or burning when urinating, frequent trips to the bathroom, feeling like you urgently need to urinate but little comes out, foul-smelling urine, dark or cloudy urine, and lower abdominal and back pain.

If you have symptoms of a UTI, see a healthcare provider. Seek emergency medical care if you have UTI symptoms along with a fever, bloody urine, and intense back or side pain.