Pyelonephritis is an acute bacterial infection and inflammatory condition of the kidney and the renal pelvis that involves either one or both kidneys.It causes the kidneys to swell and become dysfunctional, and this usually results in scarring of the affected kidney/s.

In the United States, established through a population-based study of this condition, it was found that pyelonephritis has an estimated annual incidence of 3-4 cases per 10,000 men, and 15-17 cases per 10,000 women. Approximately 80% of these cases require hospitalization due to severity of the symptoms.

An individual of any age can contract pyelonephritis. In infants below 12 months old, it is twice as common to occur in boys as in girls, and is usually linked to the presence of abnormalities of the renal tract. With children who are more than a year old, incidence becomes higher in girls. In adults, urinary tract infections become much more common again in young women, but by the age of 65, the males play catch up to the females in terms of frequency of infection cases.



Most pyelonephritis cases are the result of ordinary bladder and/or urethral infections. The causative agent enters the lower urinary tract through the urethral meatus, going up to the bladder via the urethra, then through the ureters to the kidneys. The bacteria that commonly cause the infection are Escherichia coli.

The infection can also be caused by bacteria present in the bloodstream. The staphylococcus bacteria can reach the kidney via the blood in cases like endocarditis and intravenous drug abuse.

There are also conditions or situations that increase the risk for the incidence of pyelonephritis. Among these are:

  • Conditions that restrict or reduce urine flow or cause obstruction in the urinary tract such as abdominal or pelvic masses, renal calculi, benign prostatic hypertrophy);
  • Physical abnormalities in the urinary tract (especially in neonatal cases);
  • Anatomical structure of the urinary tract (with women having shorter urethrae than men);
  • Suppressed immune systems such as in conditions akin to diabetes, cancer, or AIDS;
  • Incomplete emptying of the bladder;
  • Use of instruments and/or implements inside the urinary tract (catheters);
  • Use of certain drug therapiessuch as anticholinergics; and
  • Surgery in the urinary tract.


Signs and Symptoms

As this infection can possibly be organ-threatening and/or life-threatening, depending on its severity, it is important that the symptoms of this condition be recognized so that medical attention can be sought without delay.

The signs and symptoms of this renal infection include:

  • Fever that is usually high grade (may reach up to 103°F or more, and can be accompanied by chills);
  • Flank and/or back pain on the side of the affected kidney;
  • Nausea and vomiting;
  • Presence of blood in the urine;
  • Painful urination;
  • Increase in the frequency and/or urgency in urination;
  • Difficulty in feeding (in infants and children below 2 years of age); and
  • Confusion or change in mental status (in the elderly).



Treatment for pyelonephritis usually involves the use of antibiotics to help combat the infection. To determine the bacteria causing the infection, urine culture and sensitivity testing is conducted; this is also to ascertain the proper medication for the condition.

Those cases that do not respond to antibiotic therapy may resort to surgery such as nephrectomy, or surgical drainage if abscesses are present. Other treatment methods may also be utilized to treat the underlying conditions of pyelonephritis.


Disability Tax Credits for Pyelonephritis


Pyelonephritis can hinder an affected person in his daily activities. If you have been diagnosed with this condition, you may be entitled to disability tax credits; or if you have a child with pyelonephritis, he can be eligible for a lifetime disability savings plan from the Canadian Revenue Agency. To know more about disability tax credits for pyelonephritis and on how to secure a disability certificate for it, call the HandyTax hotline.