Symptoms

Kidney infection may cause one or more of these signs and symptoms:

• Frequent urination
• Strong, persistent urge to urinate
• Burning sensation or pain when urinating
• Abdominal pain or pressure
• Cloudy urine with a strong odor
• Pus or blood in your urine (hematuria)
• Inability to urinate (urine retention)
• Need to urinate during the night (nocturia)
• Back, side (flank) or groin pain
• Fever

Severe kidney infection also may involve:

• High fever - body temperature of 101 F (38.3 C) or greater
• Shaking chills
• Night sweats
• Extreme fatigue
• Nausea or vomiting
• Confusion

In infants and young children, signs and symptoms of kidney infection may include:

• Irritability
• Loss of appetite
• Loose bowel movements
• New episodes of bed-wetting (enuresis)

In older adults, mental changes, such as confusion, sometimes are the only signs of kidney infection.