What are the other Names for this Condition? (Also known as/Synonyms)

• Florid Von Brunn Nests
• Von Brunn Nests

What is Von Brunn's Nests? (Definition/Background Information)

• Von Brunn’s Nests is a common benign condition caused by a reactive process resulting in the formation of lesions in the urothelium (inner lining of the urinary bladder), due to the proliferation of epithelial cells
• It is reported that Von Brunn Nests is detected in between 85-95% of the bladders, mostly in the trigone area (neck region of urinary bladder) during a cystoscopic examination. If the presence of a florid collection of such nests resulting in a mass is noted, then it is large enough to be observed with a naked eye (via a cystoscope)
• Von Brunn Nests is considered to be an exaggerated variation to normal urothelium. But, nevertheless, the condition may raise a suspicion for bladder cancer on imaging studies. Sometimes, Von Brunn’s Nests are observed in the ureters and pelvis of kidney too
• Von Brunn’s Nests are typically diagnosed in adults. Some of the factors causing these abnormal growths include cancer therapy to the region, Botox injections, and other urinary bladder conditions
• Generally, no significant signs and symptoms of Von Brunn’s Nests are noted. In a majority, there is no treatment required for the condition, since it is usually asymptomatic. The prognosis of the condition is excellent, since it is only a benign reactive process

Who gets Von Brunn's Nests? (Age and Sex Distribution)

• Von Brunn’s Nests may affect individuals of any age group, although most cases are reported in adults; the incidence increasing with age
• Both male and females are affected, and no gender preference is noted
• The condition is observed worldwide; all racial and ethnic groups are affected

What are the Risk Factors for Von Brunn's Nests? (Predisposing Factors)

Following are some of the risk factors associated with Von Brunn’s Nests include:

• Advancing age
• Botox injections to the urinary bladder for an overactive bladder 
• Radiation therapy or chemotherapy to the region: In such cases, Florid Von Brunn Nests are generally noted as a reaction to irradiation, or irritation to chemotherapy medications
• Repeated bladder infections
• Urinary bladder outlet obstructions
• Presence of bladder stones (bladder calculi)
• Urinary bladder catheterisation procedures

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases one’s chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Von Brunn's Nests? (Etiology)

Von Brunn’s Nests are considered to be reactive changes occurring in the urinary bladder tissue (urothelium) due to several factors such as cancer therapy, Botox injections for overactive bladder, and urinary bladder stones, among others.

What are the Signs and Symptoms of Von Brunn's Nests?

In many cases, Von Brunn’s Nests does not present any significant signs and symptoms. In some cases, the following may be noted:

• The condition can appear as a papillary mass on cystoscopy
• Single or multiple lesions may be observed anywhere within the urinary bladder

Von Brunn’s Nests most commonly develop in the trigone region of the urinary bladder.

How is Von Brunn's Nests Diagnosed?

Von Brunn’s Nests is often an incidental cystoscopic finding, when the individual is being examined for other medical conditions. These abnormal proliferations may be mistaken for bladder cancer (such as urothelial carcinoma).

The following tests and exams may be performed in the diagnosis of Von Brunn’s Nests:

• Complete evaluation of medical history along with thorough physical exam
• Urinalysis or urine tests
• Urine culture, to check for an infection
• Cystoscopy: Special instruments are used to visually examine and study the insides of the urinary bladder
• Tissue biopsy: A tissue biopsy is performed and sent to a laboratory for a pathological examination, who examines the biopsy under a microscope. After putting together clinical findings, special studies on tissues (if needed) and with microscope findings, the pathologist arrives at a definitive diagnosis

The healthcare provider may undertake a differential diagnosis to eliminate other conditions or tumor types, before arriving at a definitive diagnosis. This may include the following:

• Adenocarcinoma in situ of the urinary bladder
• Carcinoid tumors
• Invasive urothelial carcinoma, microcystic type
• Invasive urothelial carcinoma, nested type
• Inverted urothelial papilloma
• Paraganglioma
• Tubular adenoma of the urinary bladder
• Urothelial carcinoma in situ involving von Brunn nests
• Urothelial carcinoma, nested variant

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Von Brunn's Nests?

No major complications from Von Brunn’s Nests are generally observed. In some cases, the following may be noted:

• Emotional stress due to concerns of bladder tumor/cancer
• Von Brunn’s Nests can become dilated (undergoing cystic degeneration) to form cystitis cystica; it can also undergo glandular metaplasia causing cystitis glandularis
• According to a research study, the condition may cause ureteral stenosis (narrowing of the ureter), especially after a kidney transplantation

How is Von Brunn's Nests Treated?

• In a majority, Von Brunn’s Nests may not require any treatment, unless it causes significant signs and symptoms
• Treating or removing the underlying cause of the condition is beneficial in decreasing the size of existing lesions, or in preventing the appearance of new lesions

How can Von Brunn's Nests be Prevented?

The preventive measures for Von Brunn’s Nests are mostly aimed at controlling or avoiding the factors that cause the condition. These may include:

• Ensuring adequate care while performing medical procedures involving the urinary bladder
• Taking early appropriate treatment for conditions such as bladder infections or bladder stones

What is the Prognosis of Von Brunn's Nests? (Outcomes/Resolutions)

The prognosis of Von Brunn’s Nests is typically excellent in most individuals, since it is a reactive process having no malignancy potential.

Additional and Relevant Useful Information for Von Brunn's Nests:

Please visit our Kidney & Bladder Health Center for more physician-approved health information:

https://www.dovemed.com/healthy-living/kidney-health/