Kidney infection symptoms

Kidney infections are also called pyelonephritis. They are serious infections that may require hospitalization. In the last 15 years, I have personally treated thousands of hospitalized patients with kidney infection symptoms. I am writing this article based on my personal experience as well as a review of relevant medical journals.

In this article, I will go into great details to tell you everything you need to know about kidney infection symptoms without using any medical jargon. After reading this article, you will be able to recognize kidney infection symptoms when you see them.

Types of kidney infection symptoms

There are three different categories of kidney infection symptoms:

  • Category 1: Symptoms that may be present in both kidney infections and simple urine infections
  • Category 2: Kidney pain associated with a kidney infection
  • Category 3: Systemic symptoms of a kidney infection

A kidney infection is more severe and more serious than a simple urine infection.

Click here if you would like to read the article comparing and contrasting kidney infections with urine infections.

Kidney infections may start from a simple urine infection. Kidney infections may have some or all of the symptoms of a urine infection. However, if you only have category 1 symptoms without any of the category 2 or 3 symptoms, you are more likely to have a simple urine infection instead of a kidney infection.

On the other had, you may have a kidney infection without any of the category 1 symptoms as long as you have one or more of the category 2 or 3 symptoms.

Symptoms that may be present in both kidney infections and simple urine infections (category 1 symptoms)

Here are the common symptoms that may be present in both kidney infections and simple urine infections:

  1. Increased urinary frequency: You may feel like you have to urinate frequently, but you may only have a small amount of urine each time you urinate.
  2. Urinary urgency: You may feel the urge to urinate all the time. Even a few minutes after urinating, you may feel like you have to go again. However, you may not be able to produce any urine if you go back and try.
  3. Pain with urination: You may feel a burning pain whenever you urinate.
  4. Pain over the urinary bladder: You may feel a constant gnawing pain in your lower mid-belly, over your urinary bladder.
  5. New urinary incontinence: When people unintentionally leak urine, it is called urinary incontinence. Some older people may have frequent problems with urinary incontinence, having to wear adult diapers to avoid embarrassing situations. Those types of habitual urinary incontinence is not caused by a urine infection. However, if someone suddenly starts to have urinary incontinence, it may be a symptom of a urine infection.
  6. Bloody urine: Blood in the urine can be a symptom of many different conditions, including urine infections. Any time you see blood in your urine, you need to seek medical attention and have the urine tested as soon as possible.
  7. Cloudy or foul-smelling urine: Cloudy or foul-smelling urine by itself is not necessarily a symptom of a urine infection. The odor of your urine depends on the food you eat. Urine cloudiness could be related to dehydration. If you have cloudy or foul-smelling urine and any of the other symptoms of a urine infection, you need to be concerned. If you only have cloudy or foul-smelling urine, drink more water and check again in a few hours. Call your doctor to see if you need to get your urine tested if it is still cloudy or foul-smelling.

Although these symptoms of urine infections may happen with other symptoms of kidney infections, it is important to understand that these symptoms are not always present. Many patients with kidney infections do not have any symptoms of urine infections.

Kidney pain associated with a kidney infection (Category 2 symptoms)

A diagram describing where kidney pain is felt and where the kidney is located.
A diagram showing the location of the kidneys and kidney pain

Kidney pain is a very distinct type of pain. After reading the characteristics of kidney pain, you should be able to recognize it quickly if it happens to you.

First, It is important to understand where your kidneys are located. Your two kidneys are located towards the back of your belly, one on each side. The left kidney sits a little higher than the right kidney in most people. Both kidneys are located slightly below the 12th rib on the back. They are about 10 to 12 centimeters long and 5 to 7 centimeters wide.

The area where kidney pain is usually felt is known as the flank area. The flank is the area of the body below your rib case and above your hip. You can see your kidneys and your flank area in this picture.

Kidney pain is felt in a number of different problems related to the kidneys other than kidney infections. Kidney stones, ureter stones, kidney tumors, and kidney injuries are some examples of kidney problems other than kidney infections that can cause kidney pain in the flank area. All kidney pains have similar qualities with minor differences. Kidney pains are very sharp and agonizing, feeling like they are coming from deep inside your body. The pain makes you very uncomfortable and restless. Unlike some other types of pain, you can’t find any specific body position that makes your pain better. The pain may radiate to your groin area or towards your back.

Kidney pain caused by a kidney infection could be somewhat less severe than kidney pain caused by kidney stones, but the quality of the pain is similar. If you only have category 2 symptoms (kidney pain) without any of the category 1 or category 2 symptoms, you are more likely to have kidney stones than a kidney infection. However, kidney stones can lead to a kidney infection by blocking the flow of urine and exposing it to an infection. Kidney stones and kidney infections may, therefore, happen together. If you start with category 2 symptoms but later develop category 3 symptoms, you may have started with kidney stones that later caused a kidney infection.

A simple test to confirm kidney pain

A diagram describing the steps to confirm kidney pain
A diagram showing how to confirm kidney pain

This is a simple test that can be done by hand without the need for any special equipment. This is how it is done:

  • Step 1: The patient sits upright or lies down on one side
  • Step 2: The examiner goes to the back of the patient and locates the 12th rib on the back. It is the lowest rib.
  • Step 3: The examiner places one palm in the area where the spine and the lowest rib form an angle, as seen in the picture.
  • Step 4: The examiner makes a fist with the other hand and thumps the hand sitting on the patient’s back
  • Step 5: The kidney on the side of the hand vibrates with the thump. If that kidney was the source of the paint, the patient will experience a sharp worsening of the pain.

If the patient feels a sharp worsening of the pain with the thump, kidney pain is certain. You can repeat the test on the other side to check the other kidney.

Systemic symptoms of a kidney infection (Category 3 symptoms)

These symptoms are called systemic symptoms because they affect the whole body instead of just the urinary system. You are most likely to have a kidney infection if you have kidney pain (category 2 symptoms) along with systemic symptoms (category 3 symptoms). When you only have category 3 symptoms without any category 1 or 2 symptoms, you may have a kidney infection or other serious infections. In that situation, you need to keep an open mind and let your doctors investigate further. In any case, these systemic symptoms should never be ignored, because they can lead to life-threatening complications regardless of what caused them.

Here are those symptoms:

  1. High fevers and chills: You may suddenly feel very cold, have goosebumps everywhere, or start shaking. You may also start to sweat a lot and feel feverish. Your temperature will start going up as you continue to shiver. It may go as high as 102 or 103 degrees Fahrenheit.
  2. Whole-body muscle pain: Along with high fevers and chills, you may feel muscle aches or even severe pain throughout your body. This type of pain makes you feel miserable, as if every muscle in your body is hurting.
  3. Nausea and vomiting: You may get sick to your stomach and start throwing up. Persistent nausea and vomiting may make you very weak.
  4. Fast heart rate: You may feel your heart racing in your chest. Your heart rate starts to go up as your temperature rises.
  5. Dizziness and lightheadedness: You may feel dizzy and lightheaded with high fevers, nausea, or vomiting.
  6. Excessive sweating and dehydration: You may become drenched with sweat, leading to dehydration.

A kidney infection is a common cause of sepsis. Read [Link“Low bloodLink] pressure and a fever: think about sepsis” if you would like to learn more about sepsis.

Here is a table explaining how to interpret the combination of three different categories of kidney infection symptoms:

Combination of symptomsWhat it means
Category 1 symptoms onlyMore likely to have a simple urine infection instead of a kidney infection
Category 1 + category 2 + category 3Likely to have a kidney infection
Category 2 + category 3 onlyLikely to have a kidney infection or both kidney stones and a kidney infection
Category 2 onlyMore likely to have kidney stones than a kidney infection
First category 2 symptoms, and later developing category 3 symptomsLikely to have kidney stones that eventually led to a kidney infection
Category 3 symptoms onlyMay have a kidney infection or one of the other common infections that could lead to sepsis
Three categories of kidney infection symptoms

I hope you have a clear understanding of kidney infection symptoms after reading this article. It is our attempt to put together the most comprehensive article on kidney infection symptoms that anyone can understand. After reading this article, if you still have any questions or doubts about kidney infection symptoms, please go to our contact us page and send us an email. We will update the article, including additional information that may be helpful to our readers. Remember, we will not answer any specific medical questions, but we will be happy to include any new informational topics that may be valuable to our readers.