Chronic pyelonephritis is a disease that has been damaging the kidneys for many years because of repeated (though usually unrecognized) infections caused by microorganisms in the urine.
In most cases, the disease begins in early childhood and remains unnoticed until many years later, when the symptoms of kidney problems starts to appear.
The cause of chronic pyelonephritis – bacteriae – usually reach the urinary tract through the open end of the urethra (i.e. a tube leading from the bladder to the “outside” of the body) – see the description of acute pyelonephritis. Bacteriae usually attack the lower parts of the tract, as urine leak prevents the spreading of infection by the tract. When a person is urinating, the bladder contracts and ”pushes” the urine into the urethra; at the same time, the valves close the ureter at places where they enter the bladder, thus preventing flowing of urine to the kidneys.
However, sometimes the valves are not working properly, and the bladder pushees the urine in both directions. If the urine is infected, the infection may also affect the kidneys. This combination – infection and defective valves – probably causes chronic pyelonephritis in most people. Kidney stones may also be the cause. Only in very rare cases of chronic pyelonephritis is preceded by repeated attacks of other urinary tract infections, e.g. acute pyelonephritis or cystitis.
Symptoms of chronic pyelonephritis usually occur only when the disease is in an advanced stage. Over time, early signs of chronic renal insufficiency may occur, such as frequent urination and tiredness. Nausea or itching may also occur over time.
In many cases, the disease is discovered much earlier, usually during blood or urine test (for some other reason).
In the United Kingdom, 500 cases of chronic renal insufficiency due to chronic pyelonephritis are registered annually. In most cases the patients are women. Some field studies have shown a likely kidney infection in about 2% of men and 3% of women examined. In even more patients chronic pyelonephritis leads to renal insufficiencywhich means that some people will grow old without knowing they have chronic pyelonephritis.
The disease can develop and damage the kidneys, leading to chronic renal insufficiency. However, this is rarely the case today, as increased awareness of the dangers of urinary infections in children has resulted in improved preventive treatment at an early stage.
What to do?
Self-help: if your doctor finds you have chronic pyelonephritis, even if you have no symptoms, you will be advised to stop the infection progression with these simple measures – drinking large amounts of fluid (up to three liters per day) and avoiding too much protein and salt in your meals. Your doctor will probably advise you on regular blood tests (every 6 or 12 months) to control the progression of the infection.
Professional help: a treatment depends on when the disease is discovered. An operation procedure to correct defective valves is sometimes needed in children, but this measure generally does not help adults. Any other cause of repeated infections – e.g. kidney stones – will respond to appropriate therapy. Otherwise, such infections are treated with antibiotics. Antibiotics are usually given only for a short time, i.e. whenever an urinary tract infection occurs. Sometimes, however, a longer treatment with small doses of antibiotics is needed (e.g. six months to two years) to prevent the bacteriae from appearing in the urine. Since chronic pyelonephritis usually develops slowly, many doctors do not resort to special treatment for middle-aged people, but only advise them to look after signs of renal insufficiency and go to regular medical examinations.