A kidney fungal infection is an uncommon type of urinary or kidney infection caused by fungi rather than the bacteria responsible for most urinary tract infections.

Candida species are the most common fungi associated with fungal urinary tract infections. Fungal infections can involve the bladder, urinary tract or kidneys. In some patients, fungi may reach the kidneys through the bloodstream rather than traveling upward from the urinary tract.

Fungal urinary infections are more likely in people with certain risk factors, including diabetes, weakened immunity, urinary obstruction, urinary catheters, stents or other urinary tract instrumentation.

At Prabhakar Bhurke Clinic, Dr. Sandip Prabhakar Bhurke, super specialist nephrologist and transplant physician, provides individualized evaluation of kidney infections, abnormal kidney function and complex urinary or kidney-related conditions.

Is a Kidney Fungal Infection the Same as a Normal UTI?

No.

Most urinary tract infections are caused by bacteria, whereas fungal urinary infections are generally caused by organisms such as Candida.

This distinction matters because treatment is different.

An antibiotic used for a bacterial UTI does not treat a Candida infection. Similarly, finding Candida in urine does not automatically mean that antifungal treatment is necessary.

The doctor must determine whether the organism represents colonization or an actual infection.

What Causes Fungal Infection in the Kidney?

Several factors can increase the likelihood of fungal urinary infection.

Diabetes

Poorly controlled diabetes is an important risk factor for fungal urinary infections.

Weakened Immune System

People with significant immune suppression may be more vulnerable to invasive fungal infections.

Urinary Catheters

Long-term urinary catheterization can allow Candida colonization and infection.

Urinary Stents

A ureteral stent or other urinary device can provide a surface for organisms to persist.

Urinary Obstruction

Blocked urine flow can increase the risk of complicated urinary infection.

Recent Urinary Procedures

Instrumentation of the urinary tract can increase the risk of fungal infection, particularly in susceptible patients.

Recent Antibiotic Exposure

Broad-spectrum antibiotic use can alter normal microbial populations and may contribute to Candida overgrowth.

Kidney Transplantation

Transplant recipients may have increased susceptibility to infections because of immunosuppressive treatment.

These risk factors do not prove that a person has a fungal kidney infection, but they may prompt more careful evaluation.

What Are the Symptoms of a Kidney Fungal Infection?

Symptoms depend on whether the infection involves the bladder, upper urinary tract or kidney and whether there is obstruction or systemic infection.

Possible symptoms include:

• Fever

• Chills

• Pain in the side or flank

• Pain during urination

• Frequent urination

• Urgency to urinate

• Blood in the urine

• Lower abdominal discomfort

• Nausea or vomiting

• Unexplained deterioration in kidney function

• Reduced urine output when obstruction occurs

Some people with Candida in the urine have no urinary symptoms at all. In these situations, Candida may represent colonization rather than an active infection.

Can a Fungal Kidney Infection Cause Back or Flank Pain?

It can.

When the upper urinary tract or kidney becomes involved, a person may develop pain in the flank or side of the back.

However, back pain alone does not establish a fungal kidney infection. Kidney stones, bacterial kidney infection, obstruction, muscle problems and other conditions can produce similar symptoms.

If flank pain occurs with fever, chills, urinary abnormalities or worsening kidney function, medical assessment is important.

Can a Fungal Infection Cause Blood in Urine?

Yes.

Hematuria can occur with fungal urinary infections, particularly when the urinary tract is inflamed or obstructed.

However, blood in urine has many possible causes, including:

• Kidney stones

• Bacterial urinary infection

• Glomerular kidney disease

• Tumors

• Urinary tract injury

• Other urinary conditions

Therefore, blood in urine should be investigated rather than automatically attributed to a fungal infection.

What Is Candiduria?

Candiduria means that Candida has been detected in the urine.

It does not always mean that Candida is actively infecting the urinary tract.

According to the Infectious Diseases Society of America, asymptomatic candiduria commonly represents colonization, particularly in people with risk factors such as urinary catheters. Removing or addressing predisposing factors may be sufficient in many asymptomatic patients.

Antifungal treatment is generally reserved for selected situations, including symptomatic infection and certain high-risk circumstances.

This is why a positive urine fungal culture should be interpreted by a healthcare professional.

How Is a Fungal Kidney Infection Diagnosed?

Diagnosis requires more than simply identifying Candida in a urine sample.

Urine Examination and Culture

A urine test can identify abnormalities such as:

• White blood cells

• Blood

• Yeast or fungal elements

• Other signs of urinary inflammation

A urine culture can help identify the organism and guide treatment.

Blood Tests

Depending on the patient's condition, doctors may check:

• Serum creatinine

• eGFR

• Urea

• Electrolytes

• Complete blood count

• Blood cultures when systemic infection is suspected

Imaging

Ultrasound, CT or other imaging may be used when obstruction, kidney involvement, abscess or a fungus ball is suspected.

Imaging can also help identify structural abnormalities that may be contributing to persistent infection.

Evaluation of Predisposing Factors

The doctor may also look for:

• Diabetes

• Urinary obstruction

• Stones

• Catheters

• Stents

• Previous urinary procedures

• Immunosuppression

• Kidney transplantation

What Is the Treatment for Kidney Fungal Infection?

There is no single antifungal medicine that is appropriate for every kidney fungal infection.

Treatment depends on:

• Type of fungus

• Site of infection

• Whether symptoms are present

• Antifungal susceptibility

• Kidney function

• Presence of obstruction

• Urinary devices

• Immune status

• Whether infection has spread beyond the urinary tract

For symptomatic Candida urinary infection caused by a fluconazole-susceptible organism, fluconazole is commonly recommended. For symptomatic ascending Candida pyelonephritis, IDSA guidelines recommend fluconazole for susceptible organisms and alternative therapy for selected resistant species.

The dose and duration must be determined by the treating doctor, especially when kidney function is impaired.

Why Is Kidney Function Important When Choosing an Antifungal?

Some antifungal medicines require adjustment when kidney function is reduced.

This is particularly important in patients with:

• Chronic kidney disease

• Acute kidney injury

• Kidney failure

• Dialysis

• Kidney transplantation

For example, certain antifungal medicines are substantially eliminated through the kidneys and may require dose modification.

Therefore, do not start an antifungal medicine without medical supervision simply because a fungal organism has been detected.

What Happens if the Fungus Is Resistant to Fluconazole?

Some Candida species can be resistant to fluconazole.

Treatment may then require a different antifungal approach based on the organism and its susceptibility.

For example, IDSA guidance recommends amphotericin B-based treatment or selected use of flucytosine for certain resistant Candida urinary infections.

The choice is highly individualized because antifungal medicines differ in:

• Kidney toxicity

• Urinary penetration

• Drug interactions

• Required monitoring

• Dose adjustments

What If a Kidney Fungal Infection Causes Urinary Obstruction?

This situation requires particular attention.

Fungal material can occasionally form a fungus ball in the renal pelvis, ureter or bladder. These masses can obstruct urine flow and prevent successful treatment with antifungal medicines alone.

If obstruction is present, treatment may require:

• Relief of urinary obstruction

• Endoscopic intervention

• Stent or nephrostomy management

• Removal of obstructing fungal material

• Appropriate antifungal treatment

IDSA specifically recommends eliminating urinary tract obstruction in symptomatic ascending Candida pyelonephritis.

Can Kidney Stones Be Related to Fungal Urinary Infection?

Kidney stones can contribute to urinary obstruction and complicated infections.

A person with a fungal urinary infection and a blocked urinary tract may require both infection treatment and restoration of urine drainage.

A stone should therefore be evaluated when imaging suggests obstruction or when infection keeps returning.

The treatment plan may involve urological procedures after the infection and overall clinical condition have been appropriately assessed.

What Happens if a Urinary Stent or Catheter Is Present?

A urinary device can sometimes contribute to persistent Candida colonization or infection.

When clinically appropriate, doctors may consider removing or replacing a catheter or stent.

For symptomatic ascending Candida pyelonephritis, IDSA recommends considering removal or replacement of nephrostomy tubes or stents when feasible.

The decision must be individualized and should not be made by the patient independently.

Can a Fungal Kidney Infection Spread to the Blood?

Yes, invasive Candida infection can involve the bloodstream and other organs.

However, finding Candida in urine does not automatically mean that Candida has entered the blood. Asymptomatic candiduria commonly represents colonization.

When a patient has persistent fever, severe illness or other features suggesting systemic infection, doctors may perform blood cultures and additional investigations.

Who Is at Higher Risk of Kidney Fungal Infection?

Extra caution may be appropriate in people with:

• Diabetes

• Significant immune suppression

• Kidney transplantation

• Urinary catheters

• Ureteral stents

• Urinary obstruction

• Kidney or urinary stones

• Recent urinary procedures

• Recent broad-spectrum antibiotic exposure

• Severe underlying illness

Fungal urinary infections are particularly associated with immunocompromise, diabetes, obstruction and urinary instrumentation.

Can Kidney Fungal Infection Be Treated Completely?

Many fungal urinary infections can be treated successfully when the correct organism and site of infection are identified and contributing factors are addressed.

However, treatment can be more complicated when there is:

• Resistant Candida

• Urinary obstruction

• Fungus ball formation

• Significant immune suppression

• Kidney failure

• Persistent urinary devices

• Infection outside the urinary tract

Successful treatment may therefore require coordination between nephrology, infectious disease and urology specialists.

What Should You Not Do If You Suspect a Fungal Kidney Infection?

Avoid attempting to treat the infection yourself.

Do not:

• Take leftover antibiotics

• Start antifungal tablets without testing

• Stop prescribed kidney medicines independently

• Remove a urinary catheter or stent yourself

• Drink excessive water to “flush” the infection

• Use unverified herbal antifungal remedies

Excessive fluid intake can be particularly inappropriate for people with kidney failure, heart disease, dialysis or urinary obstruction.

When Is a Fungal Kidney Infection an Emergency?

Seek urgent medical care if suspected urinary infection is accompanied by:

• High fever

• Chills or shaking

• Severe flank pain

• Confusion

• Very low or absent urine output

• Severe weakness

• Persistent vomiting

• Rapidly worsening kidney function

• Severe breathlessness

• Low blood pressure or sudden deterioration

An infected and obstructed urinary tract can become a serious medical emergency.

Kidney Fungal Infection Evaluation at Prabhakar Bhurke Clinic

At Prabhakar Bhurke Clinic, Dr. Sandip Prabhakar Bhurke, super specialist nephrologist and transplant physician, provides individualized assessment for patients with complicated kidney and urinary conditions.

Depending on the situation, evaluation may include:

• Review of urinary symptoms

• Kidney-function testing

• Urine examination and culture review

• Assessment of candiduria

• Evaluation for kidney or urinary obstruction

• Imaging review

• Assessment of kidney stones

• Medication review

• Evaluation of diabetes and immune-related risk factors

• Management of kidney complications

• Coordination with urology or infectious disease specialists when required

Treatment is based on the identified organism, infection site, kidney function and overall clinical condition.

Frequently Asked Questions

What is the best treatment for a fungal infection in the kidney?

Treatment depends on the fungal species, location of infection, symptoms, susceptibility, kidney function and presence of obstruction. Candida urinary infections may require an appropriate antifungal medicine, while obstruction or fungus balls may require an additional procedure.

Can fluconazole treat a kidney fungal infection?

Fluconazole is commonly used for susceptible Candida urinary infections because it reaches high concentrations in urine. It is not appropriate for every fungal infection or every Candida species.

Is Candida in urine always an infection?

No. Asymptomatic candiduria frequently represents colonization rather than active infection. Treatment is not routinely recommended for every asymptomatic patient.

Can a fungal kidney infection cause kidney failure?

Severe fungal urinary infection can contribute to worsening kidney function, particularly when there is obstruction or extensive infection. However, kidney failure has many possible causes and should not automatically be attributed to fungus.

Can a kidney fungal infection cause fever?

Yes. Fever may occur with upper urinary tract or systemic fungal infection. Persistent fever in a high-risk patient with candiduria may require further evaluation.

Can a fungal infection cause blood in urine?

Yes. Hematuria can occur with fungal urinary infection, although kidney stones, bacterial infection and other urinary conditions can also cause blood in urine.

Is a fungal kidney infection contagious?

A urinary Candida infection is generally not considered something that is transmitted through ordinary person-to-person contact. It usually occurs because of the patient's own Candida colonization and specific risk factors.

Which doctor treats a fungal kidney infection?

A nephrologist can evaluate kidney function and kidney-related complications. Depending on the infection and whether a urinary procedure is needed, an infectious disease specialist or urologist may also be involved.

Conclusion

Kidney fungal infection treatment requires a different approach from treatment of a routine bacterial UTI.

Candida is the most common fungal organism associated with fungal urinary infections, but the presence of Candida in urine does not automatically mean that antifungal therapy is required. Doctors must distinguish colonization from genuine infection and consider symptoms, risk factors, kidney function and imaging findings.

When symptomatic Candida infection affects the upper urinary tract, appropriate antifungal treatment may be required. If urinary obstruction, a stent, catheter or fungus ball is contributing to the infection, addressing the underlying urinary problem can be an essential part of treatment.

Because antifungal medicines can have important kidney-related dosing and safety considerations, self-treatment is not advisable.

For individualized assessment of fungal urinary infection, kidney function abnormalities and complicated kidney conditions, consult Dr. Sandip Prabhakar Bhurke at Prabhakar Bhurke Clinic.

Medical Disclaimer

This article is intended for general educational and informational purposes only and should not be considered a substitute for medical diagnosis, treatment or individualized medical advice. Fungal infections of the urinary tract and kidneys are uncommon and require appropriate clinical assessment, urine testing and, when indicated, imaging or other investigations. Finding Candida in urine does not always mean that an active infection is present, and antifungal treatment is not appropriate for every case. Antifungal selection and dosage depend on the organism, susceptibility, kidney function, other medicines and clinical condition. Do not start antifungal medicines, antibiotics or herbal remedies without professional guidance. Do not remove urinary stents or catheters yourself. Seek urgent medical attention for high fever with chills, severe flank pain, confusion, very little or no urine, persistent vomiting, severe weakness or rapidly worsening health. Consult Dr. Sandip Prabhakar Bhurke or another qualified nephrologist for personalized evaluation and treatment.