How Kidney Infection Is Treated

Kidney infections (also known as pyelonephritis) are a serious type of bacterial infection. They are treated with antibiotics. The drugs vary by the severity of the infection and the type of bacteria you have. In some cases, hospitalization is needed.

Recurrent kidney infections may be due to structural problems affecting the normal flow of urine, some of which may be congenital (present at birth). In rare cases, surgery may be needed.

Unlike some lower urinary tract infections (UTIs) that may go away on their own, upper UTIs like pyelonephritis are not left untreated because they can lead to potentially severe complications like kidney damage, kidney failure, and septicemia (the spread of infection into the bloodstream).

This article looks at the various treatments for kidney infections, including the types of antibiotics used. It also describes at-home and over-the-counter (OTC) remedies that can support treatment, as well as when surgery and other specialist treatments may be needed.

Prescriptions

Kidney infections are treated with antibiotics. The choice of antibiotics and duration of therapy can vary by the type of bacteria you have, the severity of the infection, your age and general health, and whether or not you are pregnant.

The antibiotics may be delivered orally (by mouth) for people who don't need to be hospitalized. For those who need hospitalization, the drugs are given intravenously (into a vein).

Hospitalized people also require supportive care with oral or intravenous fluids, analgesics, antipyretics, and antiemetics.

Uncomplicated Kidney Infection

For people with uncomplicated kidney infections who don't require hospitalization, oral antibiotics are prescribed for anywhere from five to 14 days.

Certain drugs and classes of drugs are preferred—such as fluoroquinolone antibiotics and Bactrim (trimethoprim/sulfamethoxazole)—but increasing rates of antibiotic resistance may limit treatment options.

Most kidney infections are caused by Escherichia coli (E. coli). In recent decades, multidrug-resistant E. coli strains have been identified. Increased rates of resistance are seen with other bacterial causes, including Klebsiella pneumonia, Pseudomonas aeruginosa, and Enterococcus faecalis.

Anyone with symptoms of acute kidney infection should get a urine culture. By providing a urine sample, the lab can identify which type of bacteria you have, and your healthcare provider can select which antibiotic is most active against it.

For uncomplicated kidney infections, the following oral antibiotics are recommended, dosed in milligrams (mg):

Hospitalized People

People with severe kidney infections or those at risk of severe complications require hospitalization. This includes people who are frail or pregnant, those who failed oral antibiotic therapy, or individuals with serious co-occurring medical conditions.

If hospitalization is required, antibiotics are delivered intravenously in milligrams or grams (g), or calculated by milligrams per kilogram of a person's body weight (mg/kg).

For hospitalized people with mild to moderate kidney infections, the following intravenous (IV) antibiotics may be used:

In less serious cases, intravenous antibiotics may be started and then transitioned to oral antibiotics.

People with severe pyelonephritis who have sepsis (a potentially deadly reaction to an infection that has spread to the bloodstream) require aggressive intravenous therapies. These include newer classes of antibiotic drugs or a combination of antibiotic drugs.

Pregnancy

Whether hospitalized or not, pregnant people need to avoid two antibiotics that can cause harm to a fetus, including congenital disabilities:

• Bactrim (sulfamethoxazole and trimethoprim)
• Gentamicin

Other newer antibiotics are used with caution in pregnant people because there are limited studies available to assess their safety. The following may be used if the benefits of treatment outweigh the risks:

• Avycaz (ceftazidime/avibactam)
• Merrem IV (meropenem)
• Primaxin (imipenem/cilastatin)
• Vabomere (meropenem/vaborbactam)
• Zerbaxa (ceftolozane/tazobactam)

Children

Studies suggest that oral antibiotics alone are as effective in children with kidney infections as a short course of intravenous antibiotics followed by oral antibiotics for 10 to 14 days.

In children with a kidney infection, the recommended oral antibiotics (and antibiotic dosages) vary by the child's age and weight.

When intravenous antibiotics are used, a short course (three to four days) followed by oral antibiotics is as effective as a longer course (seven to 10 days).

Home Remedies and Lifestyle

Kidney infections are not treated with home remedies, but certain at-home treatments may improve symptoms and help you recover as you undergo antibiotic therapy.

These include:

• Drinking plenty of water: Keeping well hydrated can help flush bacteria, waste, blood, pus, and acids out of the kidney and aid with healing. The aim is to urinate frequently and empty the bladder completely.
• Heat application: Applying a heating pad or hot water bottle to your belly, back, or side may help ease kidney pain. It also promotes blood circulation, which can aid with healing. (Do not fall asleep with a heating pad on, as overheating the kidneys can cause more harm than good.)

Because of how serious kidney infections can become, it’s important that you don’t rely on home remedies if you have signs of an acute infection.

Over-the-Counter (OTC) Therapies

As with home remedies, OTC therapies are intended to alleviate symptoms of kidney infection. They do not treat the infection and are not a substitute for antibiotics.

Your healthcare provider may recommend the following types of OTC medication if you are being treated for kidney infection:

• Nonsteroidal anti-inflammatory drugs (NSAIDs): This class of drugs, which include Aleve (naproxen) and Advil (ibuprofen), reduces pain and swelling caused by inflammation. NSAIDs should be used with caution in people with chronic kidney disease (CKD) as they can impair the function of the kidneys if overused.
• Tylenol (acetaminophen): This painkiller is both an analgesic (pain-relieving) and antipyretic (fever-reducing). Tylenol is often recommended for people with CKD as they are less likely to affect the kidneys than NSAIDs.
• Antiemetics: These drugs can be used to reduce nausea and vomiting. OTC options include Kaopectate or Pepto-Bismol (bismuth subsalicylate) and Dramamine (dimenhydrinate).
  

Surgeries and Specialist-Driven Procedures

Although a kidney infection can return if a person doesn't take their antibiotics as prescribed, there are other reasons why someone may experience recurrent bouts of infection (referred to as chronic pyelonephritis).

One of the most common causes is vesicoureteral reflux (VUR), in which urine flows backward from the bladder to the kidneys. VUR is often caused by congenital abnormalities of the ureters (the tubes that drain urine from the kidneys to the bladder). In fact, between 30% and 45% of children with severe urinary tract infections have VUR.

VUR can also be caused by an obstruction in the urinary tract or the malfunctioning of nerves controlling the bladder.

If VUR is causing chronic pyelonephritis, your healthcare provider may recommend antibiotics for acute episodes. But if recurrence is causing kidney damage, the following treatments may be needed:

• Endoscopic injection: This involves the insertion of a narrow scope into the urethra (the tube through which urine exits the body) to inject a biodegradable gel called Deflux near the opening of one or both ureters. This creates a hardened bulge.
• Urethral reimplantation: This is a surgery in which one or both of the ureters are repositioned to correct the backflow of urine from the bladder. It can be done endoscopically (through the urethra), laparoscopically (through keyhole incisions in the abdomen), or with open surgery (using a scalpel and sutures).

Complementary and Alternative Medicine (CAM)

No CAM therapies can treat kidney infections or replace antibiotics in their first-line treatment. With that said, there are natural remedies that may prevent lower UTIs, which can migrate to the kidneys and cause pyelonephritis.

These include:

• Cranberry juice: This popular remedy remains controversial but is thought to prevent bacteria from sticking to the walls of urinary vessels and organs. There is evidence that cranberry juice (as opposed to cranberry pills, powders, or tablets) can prevent kidney infections in people susceptible to recurrence.
• Vitamin C supplement: Also known as ascorbic acid, these supplements are thought to increase the acidity of urine, creating a hostile environment for bacteria. Even so, the association between vitamin C and UTI reduction remains weak.
• Probiotics; Lab studies suggest that the probiotic bacteria Lactobacillus acidophilus and Lactobacillus casei are active against E. coli and may lower the risk of UTIs. While studies are lacking, some research suggests that probiotic foods or supplements may help support antibiotic therapy.

Summary

Kidney infections (pyelonephritis) are treated with antibiotics. The antibiotics are selected by the type of bacteria you have, the severity of the infection, your age, and pregnancy status. A urine culture can help select the drugs with the strongest activity against your specific bacteria.

Other home remedies and over-the-counter or prescription drugs may be used to reduce pain, fever, and nausea. These include heating pads, OTC painkillers, and antiemetic drugs.

Surgery and other special procedures may be needed if recurrent kidney infections are caused by vesicoureteral reflux (VUR), in which urine flows back from the bladder to the kidneys.