Kidney infection: Symptoms, causes, and treatment (original) (raw)

Kidney infections (pyelonephritis) can occur when bacteria from the urinary tract travel up the urethra and affect one or both kidneys.

Sometimes, the bacteria that cause kidney, or renal, infections come from another part of the urinary tract, such as the bladder, ureters, or urethra.

Kidney infections most commonly affect people who already have a bladder infection, females, and those who are pregnant.

People who experience symptoms of a kidney infection should seek medical attention as soon as possible, as the condition may cause permanent kidney damage or spread to other parts of the body.

This article will explain the symptoms of a kidney infection and how doctors diagnose and treat it.

Males and females with a kidney infection may have similar symptoms.

The American Kidney Fund notes that females are more likely to contract a kidney infection. A female’s urethra is typically shorter than that of a male. A female’s vagina and anus are also closer to the urethra. This can make it easier for bacteria to enter the body via the urinary tract. Pregnant people are also more likely to develop a UTI or kidney infection.

A kidney infection develops due to bacteria or viruses entering the urethra and reproducing in the bladder, triggering an infection. Typically, a kidney infection results from a bladder infection that travels to the kidneys.

An infection may happen when pathogens transfer from the bowel to the genitals during sexual intercourse or through accidental transference of feces to the urethra while wiping with toilet paper after a bowel movement.

The American Kidney Fund notes that risk factors of kidney infection include:

• kidney stones
• having a urinary catheter
• an enlarged prostate in males
• having a urinary tract shaped in a way where urine may not pass through easily
• having vesicoureteral reflux, where the urinary tract allows urine to flow back up into the ureters
• pregnancy
• diabetes
• a weakened immune system because of medication or a medical condition
• a spinal cord injury or nerve damage that could block symptoms of a bladder infection

If a person suspects they have a kidney infection, their doctor or another healthcare professional will likely recommend a urine test. The usual course of treatment for a kidney infection is antibiotics, though some people require other forms of treatment.

Antibiotics

If a person’s symptoms suggest an infection, a doctor may prescribe antibiotics before the test results return. A person may also take pain relief.

It is essential to finish the whole course of antibiotics. When test results return, the healthcare professional may change the antibiotic to one that will treat the infection more effectively.

Types of antibiotics

The antibiotics a doctor prescribes depend on the individual and their medical history. Some people may be sensitivite to certain antibiotics. The first treatment usually involves a general antibiotic, with stronger medication available if the first one fails.

Antibiotics for the treatment of a kidney infection may include:

• nitrofurantoin
• trimethoprim/sulfamethoxazole
• fosfomycin
• pivmecillinam hydrochloride
• amoxicillin
• cephalexin
• ciprofloxacin
• cefuroxime
• amoxicillin-clavulanate

Fluids

When a person has a kidney infection, it is essential to consume plenty of fluids to help prevent fever and dehydration. Fluid intake recommendations may vary depending on the type of infection.

Hospital treatment

A person whose symptoms are not improving or who has more severe symptoms may require treatment in the hospital. Some people may need intravenous antibiotic treatment through a vein in their arm.

If a person experiences dehydration, fluids may be administered with a drip. According to the NHS, people will stay in the hospital for 3 to 7 days.

Surgery

A person who has a kidney stone or enlarged prostate that is blocking their urinary tract may require treatment through surgery.

A medical professional will usually check a person’s medical history for health conditions that link to a kidney infection. Diagnostic procedures may include:

• Physical examination: A medical professional will conduct a physical examination, checking a person’s general state of health, including heart rate, blood pressure, temperature, signs of dehydration, and respiratory rate. A healthcare professional will assess the mid to lower back for pain, sensitivity, or tenderness.
• Rectal examination: If a person is male, a medical professional may carry out a digital rectal examination to check for an enlarged prostate blocking the neck of the bladder.
• Pelvic examination: If the person is a young female, the doctor may carry out a pelvic examination to verify whether there is any pelvic inflammatory disease. A female may also need to take a pregnancy test.
• Urine sample: A person will collect a mid-stream urine sample in a special container for lab analysis. If the urine sample contains bacteria and white blood cells, it could indicate an infection. Both symptoms and lab results can help in diagnosis.
• Imaging: A healthcare professional may request imaging of the kidney area, such as a CT scan, MRI scan, or ultrasound.

If a person does not seek prompt treatment for a kidney infection, there is a risk of serious complications, including:

• Emphysematous pyelonephritis (EPN): This is a very rare, potentially fatal complication. EPN is a severe infection in which necrotizing bacteria destroy kidney tissue. Symptoms include fever, nausea, abdominal pain, vomiting, and confusion. Risk factors include women living with diabetes. A person may require surgery if they have this condition.
• Kidney abscesses: Pus can accumulate in kidney tissues in abscesses. Symptoms include blood in urine, weight loss, and abdominal pain. Sometimes, surgery is necessary to drain the pus. Risk factors include kidney stones, pregnancy, and diabetes.
• Acute renal failure: One or both kidneys may stop working if a person has acute renal failure. A person may need dialysis while treatment starts to take effect.
• Renal vein thrombosis: A blood clot in one of the major kidney veins may result in a lack of blood reaching the organ. This condition can cause acute kidney injury or chronic kidney disease.
• Blood poisoning, or sepsis: Sepsis is a medical emergency that needs swift medical diagnosis and treatment. It results from an extreme immune system reaction. Initial symptoms of sepsis may include:
  • difficulty breathing
  • fever, chills, or shivering
  • sweaty or clammy skin
  • changes in skin color and swelling around a wound
  • severe pain or discomfort

Risks of complication

Anyone who suspects they have a kidney infection should seek prompt medical attention. Kidney infections are more likely to cause complications in:

• males
• pregnant females who may have asymptomatic infections
• people with an obstruction in the tubes from the kidneys
• people with a weak immune system
• older adults
• hydronephrosis
• kidney stones
• colovesical fistula
• a person who has had a catheter inserted or as a result of relying on a catheter after medical procedures
• infections that occur or persist despite good treatment

A person who does not seek medical advice could develop serious complications.

Contact a healthcare professional if a person is:

• experiencing persistent or severe pain in the mid to low back or side
• feeling shivery or has a fever
• confused
• breathing rapidly or has a high heart rate
• experiencing shortness of breath

Often, a kidney infection results from a preexisting infection in the urinary tract. The best way to help prevent a kidney infection is by taking steps to help avoid an infection in the urethra or bladder. The American Kidney Fund offers some tips to help prevent a kidney infection. These include:

• Hydration: Drink plenty of fluids, particularly water.
• Urination: Urinate whenever there is an urge. Do not wait.
• Sexual intercourse: Urinate after sexual intercourse. Wash the genitals before and after intercourse.
• Hygiene: Wash the genitals every day. Do not use deodorant sprays or a douche on the genitals.
• Toilet hygiene: After passing stools, wipe the anus from front to back. This reduces the risk of spreading bacteria to the genitals.
• Fiber: Eat plenty of fiber so that stools pass easily and do not cause irritation or skin lesions. Constipation increases the risk of developing a kidney infection.

A kidney infection can be due to various conditions, the most common of which is a UTI. Females of all ages are more likely to contract a kidney infection than males.

Treatment typically includes a short course of antibiotics. Some people may require additional treatment.

A person should consult a medical professional if they suspect a kidney infection. Some infections can lead to more serious conditions that may require hospital treatment.