Chronic Pyelonephritis refers to repeated or persistent kidney infection over a long period of time. This is not as common as the acute form. It majorly affects children and people with obstruction along the urinary tract or inherent distortion of the urinary tract.

What are the symptoms of chronic pyelonephritis?

The symptoms experienced by persons with chronic pyelonephritis may be vague and nonspecific. Sometimes, symptoms may be absent. Listed below are some of the symptoms you may feel: 

1. Fever
2. Flank pain
3. Abdominal pain
4. Malaise (generalised body weakness, fatigue, and general lack of interest in activities)

What is the mechanism of chronic pyelonephritis? 

Chronic kidney infection is usually due to partial obstruction to urine flow, leading to reflux of infected urine back into the kidneys. This obstruction may be due to scaring along the urinary tract following previous urinary tract infection or surgery; kidney, ureteric or bladder stone; tumour along the urinary tract etc.

What investigations are necessary for chronic pyelonephritis? 

Urinalysis may reveal urinary sediments, granular casts and kidney epithelial cells as well as pus cells. Protein in urine is more common and may be massive, depending on the amount of damage the kidneys have undergone due to reflux of urine from the bladder through the ureters into the kidneys.

Urine culture for identification of the organism and antibiotics sensitivity of the organism is necessary as there may be resistance due to repeated use of antibiotics. Culture may be negative or positive for bacteria, mainly Escherichia coli and other gram-negative bacteria.

Imaging studies such as ultrasound, CT scan and intravenous urography (IVU) are particularly important here to detect the site of obstruction or structural abnormality of the urinary tract.

What is the treatment modality for chronic pyelonephritis? 

1. Antibiotics – The treatment of chronic pyelonephritis entails giving long-term antibiotics, usually according to sensitivity as well as analgesics (pain relief), where necessary.
2. Surgery – Surgery may be needed in recurrent pyelonephritis resulting from urinary obstruction due to kidney stone, kidney tumour, scar along the urinary tract, abnormal structure of the urinary tract or to drain abscess (pus) that fails to respond to antibiotics. Part of the kidney may need to be removed if the abscess has affected the tissue of the kidney to the extent that that part of the kidney may not recover with only antibiotic treatment. This part may constitute a site of recurrent infection if it is not removed. 

What are the complications of chronic pyelonephritis?

1. Kidney abscess (pus)
2. Bacteremia (bacteria blood) leading to sepsis
3. Chronic kidney failure
4. Frequent exacerbations of acute pyelonephritis