Introduction

Interstitial cystitis (IC) and pyuria are connected with each other in multiple ways. Pyuria, the presence of white blood cells (WBC) in the urine, is one of the key findings in interstitial cystitis, and is misdiagnosed in many cases as urinary tract infections (UTIs) because of the same clinical finding in both — pyuria.

Pyuria is not the only deciding factor of interstitial cystitis; let’s understand both conditions.

Understanding pyuria

Pyuria is the presence of WBCs in the urine, which may or may not be due to infection. The most common cause of pyuria is inflammation in the urinary tract. 

Pyuria is of two types:

• Infectious pyuria 
• Sterile Pyuria

Infectious pyuria

This type of pyuria is found in bacterial infections of the genitourinary tract. It is always present as a result of bacterial infection.¹

Sterile pyuria

Sterile pyuria is detected when a urine sample contains more than 10 WBCs/mm³ (a measurement for WBC in a sample)without bacteria. The name sterile pyuria can be considered a misnomer, as it can be detected in a few infections other than bacterial infections.

Sterile pyuria can be detected in cases of other infections caused by mycobacterium tuberculosis, viruses, fungi, and protozoan species.² Therefore, it is a little challenging to find the exact cause of it.

Therefore, we can say sterile pyuria is found with or without infection

The most common causes of sterile pyuria related with any infection:²

• Genitourinary Tuberculosis
• Sexually Transmitted Infections
• Viral infections
• Fungal infections
• Parasitic infections
• Inflammation outside the urinary tract
• Malignancy

The most common cause of sterile pyuria without infection:³

• Polycystic kidney
• Use of urinary catheter
• Urinary tract stones
• Urinary fistula
• Rejection of a renal transplant
• Interstitial cystitis

Exploring interstitial cystitis

Interstitial cystitis (IC), also called bladder pain syndrome( BPS), is a chronic inflammatory condition of the urinary bladder that lasts for more than 6 weeks, and pyuria is one of the diagnostic markers. It is characterised by symptoms such as pain, discomfort, urgency and increased frequency of urination.⁴

Symptoms and diagnosis

It is a little challenging to directly diagnose intersitial cystitis as there is no single test to diagnose it. Several tests are done to rule out other diseases with similar symptoms. Different diagnostic tests, such as urine examination, ultrasound, are done to identify the intersitial cystitis. 

The main symptoms associated with the intersitial cystitis are:⁵

• Pain in the lower abdomen
• Pressure
• Discomfort
• Urge to pee
• Increased frequency of urination

Potential causes and risk factors

The actual cause of interstitial cystitis is not well known, but recent researches suggest inflammation to be the underlying cause.

Cystoscopy findings in patients with intersitial cystitis/bladder pain syndrome suggest loss of mucosal barrier in the urinary bladder, which is the urothelium.. This could be the possible reason for increased antibodies and immunity mediators in the urine, reflecting chronic inflammation.

Some of the probable causes of intersitial cystitis are the following: 

• Autoimmune diseases
• Chronic inflammation
• Increase in the gray matter volume, causing high pain sensitivity
• Mast cell dysfunctionUrothelial dysfunction

The link between pyuria and interstitial cystitis

Pyuria is the presence of WBCs in the urine culture, and interstitial cystitis is a chronic inflammatory disease of the urinary system. Pyuria is one of the frequent findings in urine examinations of interstitial cystitis.

The type of pyuria present in interstitial cystitis is sterile pyuria, without any bacterial infection. It is mostly confused with other urinary diseases, especially urinary tract infections (UTI).⁶

Research findings

Research findings suggest that sterile pyuria is present in the case of interstitial cystitis. Presence of WBCs does not rule out other possibilities. If a urinary tract infection (UTI) is suspected, a culture and sensitivity test is needed.

Persistent sterile pyuria may point to other infections including Mycoplasma and Corynebacterium species.⁷

What is the importance of connection?

Diagnosing interstitial cystitis is most challenging because of the lack of a single confirmatory test.⁴ The symptoms of interstitial cystitis mimic those of UTI, therefore, can misleaddoctors and leads to unwanted antibiotic therapy.

Multiple tests must be done to rule out other diseases, so that a proper treatment can be given. 

The most common diagnostic tests are:⁸

• Urine analysis
• ytoscopy
• ltrasound
• MRI
• CT scan of the urinary tract and kidneys

Management strategies

The American Urological Association suggests education about the complexities of the disease before initiating treatment.⁷ 

The management strategies for interstitial cystitis include: 

• Lifestyle modifications
• Medical Treatments

Lifestyle modifications

Lifestyle modifications can help reduce the symptoms of interstitial cystitis. A few lifestyle changes, such as a healthy diet, exercise, and stress management, have helped many patients alleviate the pain.⁹

Reduced consumption of tea, coffee, spicy foods, and chocolates has helped reduce the symptoms of people suffering from interstitial cystitis.⁹

Medical treatments 

The medicinal treatment aims to relieve the pain of patients at different levels by aiming to reduce general pain, neural pain and the urge to urinate 

Proper diagnostic tests must be done to rule out other related diseases like UTI, sexually transmitted disease (STD), and malignancies.

The most effective medicine for interstitial cystitis include: 

• Amitriptyline
• Cyclosporin A
• Pentosan-polysulfate. 

Amitriptyline and Cyclosporin A

It is an antidepressant and helps in reducing chronic pain, whereas cyclosporin A is an immunosuppressive drug.

Pentosan polysulfate 

Is the only oral drug approved by FDA for the treatment of IC. It helps in restoring the bladder epithelium lining, hence further restoring the functions of the urinary bladder.⁴

Proper diagnostic tests must be done to rule out other related diseases like UTI, sexually transmitted disease (STD), and malignancies.

FAQs

Can someone have pyuria without an actual infection?

Yes, pyuria can occur without an actual infection, too. Pyuria is actually the presence of WBCs in the urine. It is usually seen in cases of infections like UTIs, but can also be seen without infection, which is called sterile pyuria. Inflammation and infections, which are non-bacterial, can also lead to pyuria.

How is pyuria linked with interstitial cystitis?

Interstitial cystitis is a chronic inflammatory condition of the urinary bladder. It is marked by the presence of WBCs in the urine analysis, which is pyuria. Pyuria is also seen in many other urinary tract diseases, along with interstitial cystitis.

What is sterile pyuria?

Sterile pyuria is the presence of WBCs in the urine without any bacterial presence. The word sterile is a misnomer, as sterile means without any infections; however, sterile pyuria can be present in other infections, like fungal, protozoan, etc.

Why is it important to differentiate between IC and UTI in patients with pyuria?

The main symptoms of urinary tract infection (UTI) are similar to those of interstitial cystitis, including pain in the lower abdomen, fullness in the bladder, increased frequency of urination, and, in some cases, burning sensation. The urine analysis also suggests pyuria in both cases; this can lead to wrong diagnoses and wrong treatment.⁶

In UTI, along with pyuria, bacteria are also seen in the urine examination, confirming an infection. Therefore, antibiotics are the right choice of treatment for UTIs. But in the case of IC, there is no bacteria; therefore, incorrect treatment can lead to unwanted consumption of antibiotics. This can lead to resistance to the antibiotics without any relief from the disease.

When to seek medical advice?

We need medical advice when symptoms like consistent pain, discomfort, burning sensation, and increased frequency in urination are present to an extent that is affecting our daily routine.¹⁰

Summary

Pyuria is the presence of WBCs in the urine, and interstitial cystitis is a chronic inflammatory disease of the urinary bladder. Both are interlinked, as pyuria is one of the main findings in the urine analysis of IC. The type of pyuria found in interstitial cystitis is sterile pyuria, which means without any bacteria.

Interstitial cystitis is misdiagnosed as UTI in most cases because of similar symptoms and pyuria as common factors. The main aim in understanding the link is to prevent incorrect treatment of interstitial cystitis, which leads to unnecessary use of antibiotics.

There is no single test to diagnose interstitial cystitis; therefore, multiple tests such as urine examination, ultrasound, and cytoscopy are done to rule out other diseases. 

The management of interstitial cystitis includes lifestyle and diet modifications: stress management, physiotherapy, healthy diet, and reduction in consumption of tea, coffee. 

We must seek medical advice if any of the symptoms occur and affect our daily lives.