What is pyelonephritis and what types are there?
Acute pyelonephritis is a urinary tract infection that originates in the urinary tract and subsequently rises to the kidney -up to one of them or even both.
The fact that it is a complicated or uncomplicated acute pyelonephritis will determine the prognosis , depending on whether there are anatomical or functional alterations of the urinary system
For example, it is complicated acute pyelonephritis if there are kidney stones , cystic kidney disease, some obstruction, anatomical abnormalities, foreign bodies, diabetes , pregnancy or kidney transplant .
If treated early and correctly, acute pyelonephritis usually heals without sequelae , but if it continues, it can become complicated and cause lesions that atrophy the kidney or even cause septicemia.
Therefore, acute kidney infection, especially when it is not treated early, especially if there are alterations in the urinary tract, can evolve into a chronic one, characteristically causing permanent kidney damage and destroying kidney tissues. This situation is called chronic pyelonephritis.
Who is affected?
Acute pyelonephritis in its uncomplicated form mainly affects healthy nonpregnant women with a normal genitourinary tract. Risk factors for cystitis , such as a sexually active life, the use of spermicides, or a family history of urinary tract infection, also predispose to the development of acute pyelonephritis.
What is the cause of kidney infection?
Pyelonephritis usually occurs because microorganisms present in the anus or vagina spread to the urethra, bladder, or ureter and ascend to the kidney . The bacterium Escherichia coli -responsible for cystitis- is usually the infectious agent involved in most cases.
Although rare, bacteria that cause infections in other parts of the body can also reach the kidneys through the bloodstream and cause an infection there.
What are the risk factors for developing pyelonephritis?
Kidney stones , which can cause obstruction in the urinary tract , anatomical changes in the urinary tract, having a urinary catheter or surgery that has affected the urinary tract, or having a large prostate can also cause different degrees of obstruction and, therefore, promote the onset of kidney infections. In the elderly, it may be the result of general deterioration or urinary incontinence problems .
In addition, a weak immune system or recurrent cystitis are risk factors for pyelonephritis . In addition, diabetic women have a higher risk of suffering from it -although not men- and pregnancy entails a greater probability of pyelonephritis during the last trimester .
In children, the risk is higher with vesicoureteral reflux, a condition that causes part of the urine stream to back up from the bladder into the ureters and kidneys.
Other people have injuries to the nerves that surround the bladder, which decreases its sensitivity to detect infections of the lower urinary tract, making them more prone to kidney infections because they cannot be detected early.
This is the case of frail elderly people and others especially affected by this circumstance, such as people with paraplegia, who also usually carry catheters or other medical devices in the urinary tract, due to which they frequently suffer from infections and hospitalizations.
What symptoms do you have?
The most common symptoms of pyelonephritis are fever, lower back pain , malaise, vomiting, nausea, and chills . The patient may also present the symptoms of other infections – cystitis , urethritis or prostatitis-, which may have caused the kidney infection. In this case, there may be, for example, more desire to urinate -sometimes urgently-, itching and burning when doing so, blood in the urine, whitish or purulent-looking urine, etc.
Although it tends to be more common in complicated forms of the disease, pyelonephritis can progress to bacteremia -the presence of bacteria in the bloodstream-, severe sepsis and septic shock.
In some specific population groups, for example, in the elderly, the symptoms may not be so clear and manifest as diffuse abdominal pain, drowsiness, affectation of the general state or a fever without a clear clinical origin.
How is pyelonephritis treated?
Treatment consists of resting, drinking fluids in adequate amounts to facilitate the elimination of bacteria through urine , relief of fever and pain with analgesics and antipyretics, and early administration of antibiotics .
The choice of one or the other and the route of administration – intravenous, oral or both consecutively – will depend on the type of germ that has caused the infection, its location and along with the other factors.
In severe cases, complicated pyelonephritis or resistance to initial antibiotic treatment , hospital admission may have to be resorted to. In the case of chronic pyelonephritis, a complete evaluation is necessary, since surgical intervention may be required to correct any anatomical abnormalities and, thus, possible new infections.
