What Is Kidney Abcess?
Kidney and Urologic Diseases Data Verified

Kidney Abscess - Types, Causes, Risk Factors, Symptoms and Treatment.

Published on Oct 17, 2022   -  5 min read


A kidney abscess is a confined pocket of pus that develops in the renal tissue due to various reasons. To know more about this, read the content below.


A kidney abscess, also known as a renal abscess, is the circumscribed collection of pus in the renal parenchyma. They are believed to be caused as a result of the liquefaction phase of localized bacterial nephritis or hematogenous spread of infection from another site. It results from infection of the kidney by different bacterial species due to a variety of reasons. Most cases of renal abscess are reported to be caused as a result of urinary tract infections. Kidney abscess accounts for 0.2 % of all abdominal abscesses.

What Is Kidney Abscess?

A kidney abscess can be defined as the localized collection of pus in any part of the renal tissues leading to the spread of infection and other complications. It may appear as a complex lesion or intrarenal fluid collection layered by the inflammatory cells.

Based on the anatomic location of the abscess in the kidney, it can be categorized into three types,

  • Perinephric Abscess - A perinephric abscess is a collection of pus in the perinephric fat (layer of fat surrounding the kidneys) and fascia surrounding the kidney.

  • Renal Cortical Abscess - It is a term to describe the collection of pus in the renal cortex.

  • Corticomedullary Abscess - A corticomedullary abscess is a collection of pus in the space joining the renal medulla and cortex.

Studies report that kidney abscesses resulting from focal infection usually result in abscesses in the medulla, whereas the hematogenous spread from a remote site will result in a cortical abscess. Either type can crack into the perinephric space causing a perinephric abscess.

What Are the Causes of Kidney Abscess?

The main cause of kidney abscesses is urinary tract infection (UTI). Other causes include:

What Are the Risk Factors for Kidney Abscesses?

  • Diabetes Mellitus - Patients with Increased and uncontrolled blood sugar levels are at increased risk of kidney abscess as the bacterias proliferate in the environment rich in glucose.

  • Traumatized Kidney - Any type of injury to the kidneys would result in a kidney abscess.

  • Skin Abscesses - Any pus collection in the skin can metastasize to the kidneys.

  • Pregnancy - Pregnancy can also be a risk factor as urinary tract infections are more common in pregnancy.

  • Intravenous Drug Abuse - As chances of infection are more in these patients.

  • Immunocompromised State - Immunocompromised patients are at high risk due to the lack of immunity against pathogens.

What Is the Pathogenesis of Kidney Abscess?

Renal abscesses arise as a result of preexisting kidney disease or due to the hematogenous spread of infection from a distant site. Infection in the kidney is mainly caused by organisms such as Escherichia coli, Proteus, and Pseudomonas species, whereas the infection from a distant site is most commonly caused by Staphylococcus aureus. Infection by these organisms either from the local or distant site will lead to the formation of abscess, which is characterized by the intrarenal accumulation of fluid composed of dead cells and bacterial material in the center surrounded by collagenous tissue.

What Are the Symptoms of Renal Abscess?

  • Pain during urination.

  • Pyuria (presence of pus in the urine).

  • Hematuria (blood in the urine).

  • Weight loss.

  • Night sweats.

  • Abdominal pain.

  • Fever and chills.

  • Back pain.

How to Diagnose Renal Abscess?

Diagnostic tests include:

  • Complete Blood Count - This will reveal the increased number of white blood cells (leukocytosis).

  • Erythrocyte Sedimentation Rate (ESR) and C-reactive Protein (CRP) - Values are elevated, indicating active infection.

  • Blood Culture - Reveal the growth of organisms in the blood.

  • Gram Staining - Done to understand whether the organism causing the infection is gram-positive or negative.

  • Urine Test - Reveals the presence of causative bacteria and pus in the urine.

  • X-ray - This is the least advisable, as small abscesses are hard to appreciate in X-ray.

  • Kidney Ultrasound - Kidney ultrasound helps visualize the abscess.

  • Computerized Tomography (CT scan) - CT scan is the most preferred method to diagnose kidney abscesses.

What Are the Complications of Renal Abscesses?

Renal abscesses, if left untreated or unnoticed, may lead to the dissemination of the organisms throughout the body, causing a life-threatening condition called sepsis.

What Is the Prognosis of Renal Abscess?

Renal abscesses show a good prognosis with early recognition of the condition and treatment with appropriate antibiotics. The prognosis is reported to be bad when it progresses to sepsis.

What Is the Treatment for Renal Abscesses?

The various methods in the management of renal abscess involve:

Incision and Drainage

Once the kidney abscess is diagnosed, it is important to clear the infection by draining the pus through incision and drainage. Drainage of pus results in decreased bacterial load and increased renal perfusion, and the antibiotics can be delivered effectively. Incision and drainage in case of larger abscess need surgical intervention where a catheter is placed surgically to drain the abscess.

Percutaneous Drainage

It is a less invasive procedure in which the catheter is placed in the kidney with the aid of imaging guidance. With the CT or ultrasound guidance, the catheter is inserted into the skin over the kidney, and the pus is drained. The advantages of this technique include decreased morbidity by offering faster recovery than the open surgical technique, preserving the kidney by avoiding unnecessary damage to the kidney tissues, and the procedure can be performed under the local anesthetic.


Antibiotics should be given based on the causative agents, appropriate choice of antibiotics is mandatory in the treatment of this condition. Studies have shown that around 75 % of kidney abscesses are caused by gram-negative bacteria, Escherichia coli (E-coli) being the most common organism; hence antibiotics should be chosen based on the culture reports. Intravenous (IV) administration of antibiotics is found to be more effective in managing it well.

Treating the Underlying Cause

The underlying cause for the formation of the renal abscess should be treated to prevent the recurrence of the condition. If kidney stones are present, they should be removed to avoid obstruction and reinfection of renal tissues.


A kidney abscess is an infectious condition where the pus accumulates in the renal tissue. With timely diagnosis and prompt treatment, the prognosis of this condition is good. Percutaneous nephrostomy and appropriate antibiotics are found to be the most effective in the management of kidney abscesses. The underlying conditions which serve as a secondary cause of kidney abscess should be addressed and should be eliminated to prevent reinfection or recurrence.

Frequently Asked Questions


How Serious Is Kidney Abscess?

Kidney abscesses can be severe if a person already has diabetes and is in the advanced kidney abscess phase, which is challenging to treat. However, patients with early diagnosis and treatment for kidney abscesses can have a better prognosis. Therefore, kidney abscess is a severe condition that can even cause the death of a patient.


Does Kidney Abscess Burst?

Kidney abscess burst is a rare condition mainly caused by gram-positive microorganisms. The disease mostly occurs in intranephric abscesses. The bacteria causing kidney abscess burst is Staphylococcus aureus.


When Should We Get the Kidney Abscess Drained?

Kidney abscess should be drained if the abscess size is more significant than three centimeters. Also, drainage should be done if the antimicrobial therapy is ineffective and does not resolve the problem. Therefore, large renal abscesses require drainage if there is no improvement in the patient after one week and they have persistent fever and chills.


What Are the Causes of Kidney Abscesses?

The causes of kidney abscesses include
Urinary tract infections (UTIs).
Nephritis or inflammation of the kidneys.
Polycystic kidney disease or multiple cysts formed in the kidney.
Vesicular ureteral reflux or backflow of urine.
Kidney stones.
Urinary tract surgery.


How Common Is a Kidney Abscess?

Kidney abscess is an uncommon condition, usually occurring in a person with kidney stones, inflammation, and other renal diseases. It mainly occurs in females due to urinary tract infections. Therefore, kidney abscess is a very rare condition accounting for almost 0.2% of abdominal abscesses.


What Foods Should Be Avoid if a Person has Kidney Abscess?

A person should avoid alcohol, caffeine, and various sugary drinks if they have kidney abscesses. Also, people suffering from this condition should not eat processed and fast food. In addition, people should also avoid food high in potassium and sodium or salt.


What Are the Symptoms That Indicate Kidney Abscess In a person?

The symptoms of kidney abscess are as follows:
Chills and fever.
Weight loss.
Back pain.
Pyuria or pus in the urine.
Abdominal pain.
Night sweats.
Hematuria or blood in the urine.


Does Kidney Abscess Cause Kidney Failure?

Kidney abscess can lead to severe complications if left untreated in a person. In addition, the disease can cause severe kidney infection in the patient, which can cause kidney scarring. This can further lead to high blood pressure, chronic kidney diseases, and eventually kidney failure in a person.


Which Fruit Is Good for Kidney Abscess?

Foods which have anti-inflammatory properties are suitable for kidney abscess conditions. These food include apples, pineapples, cranberries, cabbage, strawberries, peaches, plums, blueberries, boiled cauliflower, etc.


Which Bacteria Causes Kidney Abscess?

Staphylococcus bacteria is responsible for kidney abscess conditions in a person. These bacteria cause infections from a distant site or locally but can lead to abscess formation in the kidney. In addition, other kidney infections are caused by Proteus, Escherichia coli, and Pseudomonas species


How Does a Person Get a Kidney Abscess?

A person can get a kidney abscess from any preexisting kidney disease or bacterial infection caused by various microorganisms. When infectious bacteria enter a person's body, the body's immune system sends white blood cells to fight infections in the affected area. Unfortunately, the attack of white blood cells on the bacteria can also cause damage or death to nearby tissues. The tissue death forms holes in the affected area, which gets filled with pus and dead tissues and, thus, causes abscess formation.


What Can Renal Abscess Lead To?

Renal or kidney abscess can lead to the following conditions:
Perinephric abscess.
Psoas abscess.


Does Kidney Abscess Go Away Without Draining?

Small kidney abscesses can go away alone or dry up naturally without treatment. However, a large renal abscess requires antibiotic therapy to treat the infection and also drainage of the pus to treat the condition. Large abscess of about more than three centimeters in size needs drainage.

Last reviewed at:
17 Oct 2022  -  5 min read




Comprehensive Medical Second Opinion.Submit your Case

Related Questions & Answers

Scarlet Fever - Symptoms, Causes, Risk Factors, Diagnosis, and Treatment

Article Overview: Scarlet fever is an infectious disease caused by a bacteria called group A streptococcus. Read the article to know about the causes, symptoms, and treatment. Read Article

Amit Jauhari
Amit Jauhari
Pulmonology (Asthma Doctors)

What Is Scarlet Fever? Scarlet fever is otherwise known as scarlatina. Scarlet fever is an infection that usually develops in people who might have an existing strep throat infection. The typical features of scarlet fever are bright red rashes on the body. They are often accompanied by sore throat a...  Read Article

Hyperparathyroidism - Types, Causes, Symptoms, and Treatment

Article Overview: Hyperparathyroidism is a disorder in which the parathyroid glands produce too much parathyroid hormone (PTH). Read the article to know more about the condition. Read Article

Shaikh Sadaf
Shaikh Sadaf

Introduction: Parathyroid glands are four pea-sized glands located in the neck behind the thyroid gland, two on each side. Parathyroid glands secrete a hormone called parathyroid hormone (PTH) or parathormone, which is responsible for regulating calcium, phosphorus, and vitamin D levels in the blood...  Read Article

Preauricular Cyst - Causes, Symptoms, Diagnosis, and Treatment

Article Overview: A preauricular cyst is a congenital (inborn) non-cancerous deformity of preauricular soft tissue. It is variably termed as a preauricular sinus or pit. Read Article

Akshay. B. K.
Akshay. B. K.
Otolaryngology (E.N.T)

Introduction The auricle is a visible part of the ear. A preauricular (front part of the ear) cyst is a very uncommon congenital deformity seen in front of the ears on facial skin. It is also variably known as preauricular sinus, preauricular fistula, and preauricular pit. Preauricular cyst occurs d...  Read Article

Popular Articles Most Popular Articles

Do you have a question on Kidney Disorders or Kidney Abscess?

Ask a Doctor Online

* guaranteed answer within 4 hours.

Disclaimer: No content published on this website is intended to be a substitute for professional medical diagnosis, advice or treatment by a trained physician. Seek advice from your physician or other qualified healthcare providers with questions you may have regarding your symptoms and medical condition for a complete medical diagnosis. Do not delay or disregard seeking professional medical advice because of something you have read on this website. Read our Editorial Process to know how we create content for health articles and queries.