As of 2010 there is insufficient evidence to determine if screening for bladder cancer in people without symptoms is effective or not.

In 2013 a preliminary, small study of 98 samples of urine, all from men—24 who had cancer, and 74 with bladder-related problems but no cancer yet used a gas chromatograph to successfully examine the vapor from heated urine samples to identify cancer.

Cystoscopy, a procedure in which a flexible tube bearing a camera and various instruments is introduced into the bladder through the urethra allows diagnosis and by biopsying suspicious lesions.

The gold standard for diagnosing bladder cancer is biopsy obtained during cystoscopy. Urine cytology can be obtained in voided urine or at the time of the cystoscopy ("bladder washing"). Cytology is not very sensitive (a negative result cannot reliably exclude bladder cancer). There are newer non-invasive urine bound markers available as aids in the diagnosis of bladder cancer, including human complement factor H-related protein, high-molecular-weight carcinoembryonic antigen, and nuclear matrix protein 22 (NMP22). NMP22 is also available as a prescription home test. Other non-invasive urine based tests include the CertNDx Bladder Cancer Assay, which combines FGFR3 mutation detection with protein and DNA methylation markers to detect cancers across stage and grade, UroVysion, and Cxbladder.

The diagnosis of bladder cancer can also be done with a Hexvix/Cysview guided fluorescence cystoscopy (blue light cystoscopy, Photodynamic diagnosis), as an adjunct to conventional white-light cystoscopy. This procedure improves the detection of bladder cancer and reduces the rate of early tumor recurrence, compared with white light cystoscopy alone. Cysview cystoscopy detects more cancer and reduces recurrence. Cysview is marketed in Europe under the brand name Hexvix

However, visual detection in any form listed above, is not sufficient for establishing pathological classification, cell type or the stage of the present tumor. A so-called cold cup biopsy during an ordinary cystoscopy (rigid or flexible) will not be sufficient for pathological staging either. Hence, a visual detection needs to be followed by transurethral surgery. The procedure is called transurethral resection of bladder tumor (TURBT). Further, bimanual examination should be carried out before and after the TURBT to assess whether there is a palpable mass or if the tumour is fixed ("tethered") to the pelvic wall. The pathological classification obtained by the TURBT-procedure, is of fundamental importance for making the appropriate choice of ensuing treatment and/or follow-up routines.

Diagnostic tests typically include complete blood tests, urinalysis, urine culture, X-rays of the abdomen and chest, and bladder imaging. The definitive diagnosis of bladder cancer will require a tissue biopsy and subsequent examination of the cells under the microscope.

Because most bladder cancers are invasive into the bladder wall, surgical removal is usually not possible. The majority of transitional cell carcinomas are treated with either traditional chemotherapy or nonsteroidal anti-inflammatory drugs.

Diagnosis is made by history and examination.

In immunocompromised patients, pus is present in the urine but often no organism can be cultured. In children, polymerase chain reaction sequencing of urine can detect fragments of the infectious agent.

The procedure differs somewhat for women and men. Laboratory testing of urine samples now can be performed with dipsticks that indicate immune system responses to infection, as well as with microscopic analysis of samples. Normal human urine is sterile. The presence of bacteria or pus in the urine usually indicates infection. The presence of hematuria, or blood in the urine, may indicate acute UTIs, kidney disease, kidney stones, inflammation of the prostate (in men), endometriosis (in women), or cancer of the urinary tract. In some cases, blood in the urine results from athletic training, particularly in runners.

The diagnosis of bladder stone includes urinalysis, ultrasonography, x rays or cystoscopy (inserting a small thin camera into the urethra and viewing the bladder). The intravenous pyelogram can also be used to assess the presence of kidney stones. This test involves injecting a radiocontrast agent which is passed into the urinary system. X-ray images are then obtained every few minutes to determine if there is any obstruction to the contrast as it is excreted into the bladder. Today, intravenous pyelogram has been replaced at many health centers by CT scans. CT scans are more sensitive and can identify very small stones not seen by other tests.

There is no standardized evaluation of the symptoms of UAB, in part due to the historic terminologic confusion. A thorough history aimed at detecting underlying disease or prior pelvic surgeries is certainly necessary. As a perception of volume mishandling, a voiding diary (to assess voided volumes and frequency of voiding) and a post-void residual volume would be valuable information. Uninstrumented uroflow, neurologic and pelvic examination may contribute valuable information. Imaging looking for abnormal bladder morphology or vesicoureteral reflux/hydronephrosis may be helpful. If low-pressure urine storage can be assured, and the urinary reservoir is known to be limited to the bladder, the general value of urodynamic study in UAB is unclear. In specific situations, invasive urodynamics may be helpful to distinguish bladder outlet obstruction from DU, although this distinction can be difficult.

The symptoms of IC/BPS are often misdiagnosed as a urinary tract infection. However, IC/BPS has not been shown to be caused by a bacterial infection and antibiotics are an ineffective treatment. IC/BPS is commonly misdiagnosed as chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) in men, and endometriosis and uterine fibroids (in women).

These lymphomas are difficult to differentiate from gastric adenocarcinoma. The lesions are usually ulcers with a ragged, thickened mucosal pattern on contrast radiographs.

The diagnosis is typically made by biopsy at the time of endoscopy. Several endoscopic findings have been reported, including solitary ulcers, thickened gastric folds, mass lesions and nodules. As there may be infiltration of the submucosa, larger biopsy forceps, endoscopic ultrasound guided biopsy, endoscopic submucosal resection, or laparotomy may be required to obtain tissue.

Imaging investigations including CT scans or endoscopic ultrasound are useful to stage disease. Hematological parameters are usually checked to assist with staging and to exclude concomitant leukemia. An elevated LDH level may be suggestive of lymphoma.

Jackstone calculi are rare bladder stones that have an appearance resembling toy jacks. They are almost always composed of calcium oxalate dihydrate and consist of a dense central core and radiating . They are typically light brown with dark patches and are usually formed in the urinary bladder and rarely in the upper urinary tract. Their appearance on plain radiographs and computed tomography in human patients is usually easily recognizable. Jackstones often must be removed via cystolithotomy.

The majority of gastric lymphomas are non-Hodgkin's lymphoma of B-cell origin. These tumors may range from well-differentiated, superficial involvements (MALT) to high-grade, large-cell lymphomas. Sometimes, it's hard to differentiate poorly differentiated high grade B-cell gastric lymphoma from gastric adenocarcinoma clinically or radiologically, yet histopathology with immunohistochemistry is recommended to stain specific markers on the malignant cell that favor the diagnosis of lymphoma. Immunohistochemistry stains specific clusters of differentiation that are present on B-cells like CD20. Cytokeratin is also a surface marker that is presented on epithelial cells, is stained histochemically and favors the diagnosis of epithelial tumors like adenocarcinoma.

Differentiating poor gastric lymphoma from adenocarcinoma is essential because the prognosis and modalities of treatment differ significantly.

Other lymphomas involving the stomach include mantle cell lymphoma and T-cell lymphomas which may be associated with enteropathy; the latter usually occur in the small bowel but have been reported in the stomach.

A diagnosis of IC/BPS is one of exclusion, as well as a review of clinical symptoms. The AUA Guidelines recommend starting with a careful patient history, physical examination and laboratory tests to assess and document symptoms of IC, as well as other potential disorders.

The KCl test, also known as the "potassium sensitivity test", is no longer recommended. The test uses a mild potassium solution to evaluate the integrity of the bladder wall. Though the latter is not specific for IC/BPS, it has been determined to be helpful in predicting the use of compounds, such as pentosan polysulphate, which are designed to help repair the GAG layer.

For complicated cases, the use of hydrodistention with cystoscopy may be helpful. Researchers, however, determined that this visual examination of the bladder wall after stretching the bladder was not specific for IC/BPS and that the test, itself, can contribute to the development of small glomerulations (petechial hemorrhages) often found in IC/BPS. Thus, a diagnosis of IC/BPS is one of exclusion, as well as a review of clinical symptoms.

In 2006, the ESSIC society proposed more rigorous and demanding diagnostic methods with specific classification criteria so that it cannot be confused with other, similar conditions. Specifically, they require that a patient must have pain associated with the bladder, accompanied by one other urinary symptom. Thus, a patient with just frequency or urgency would be excluded from a diagnosis. Secondly, they strongly encourage the exclusion of confusable diseases through an extensive and expensive series of tests including (A) a medical history and physical exam, (B) a dipstick urinalysis, various urine cultures, and a serum PSA in men over 40, (C) flowmetry and post-void residual urine volume by ultrasound scanning and (D) cystoscopy. A diagnosis of IC/BPS would be confirmed with a hydrodistention during cystoscopy with biopsy.

They also propose a ranking system based upon the physical findings in the bladder. Patients would receive a numeric and letter based score based upon the severity of their disease as found during the hydrodistention. A score of 1–3 would relate to the severity of the disease and a rating of A–C represents biopsy findings. Thus, a patient with 1A would have very mild symptoms and disease while a patient with 3C would have the worst possible symptoms. Widely recognized scoring systems such as the O'Leary Sant symptom and problem score have emerged to evaluate the severity of IC symptoms such as pain and urinary symptoms.

Various modalities of diagnosis are available:

- Cystoscopy

- Colonoscopy

- Poppy seed test

- Transabdominal ultrasonography

- Abdominopelvic CT

- MRI

- Barium enema

- Bourne test

- Cystogram

A definite algorithm of tests is followed for making the diagnosis.

Unfortunately mesna is ineffective as a treatment once hemorrhagic cystitis has developed. Although rare, once a case of radiation-induced hemorrhagic cystitis is diagnosed there is no empirically-proven treatments to heal this type of condition, which can severely degrade a patient's quality of life and might possibly lead to renal failure with risk of death.

Viral hemorrhagic cystitis in children generally spontaneously resolves within a few days.

The first step in the treatment of HC should be directed toward clot evacuation. Bladder outlet obstruction from clots can lead to urosepsis, bladder rupture, and renal failure. Clot evacuation can be performed by placing a wide-lumen bladder catheter at bedside. The bladder can be irrigated with water or sodium chloride solution. The use of water is preferable because water can help with clot lysis. Care must be taken to not overdistend the bladder and cause a perforation.. Hyperbaric oxygen (HBO2) therapy has been proven to be effective in treating radiation-induced hemorrhagic cystitis.

Splenic MZL is difficult to diagnose and can look similar to other types of lymphoma. Tests include a physical examination, blood tests to determine overall health and detect infections (ex. hepatitis C), a bone marrow biopsy, CT scan, and a PET scan. Sometimes a splenectomy is necessary during the diagnosis process in order to determine the exact type of lymphoma. If the spleen is removed, you will be at a larger risk of infection.

Gastric MALT lymphoma is frequently associated (72–98%) with chronic inflammation as a result of the presence of "Helicobacter pylori", potentially involving chronic inflammation, or the action of "H. pylori" virulence factors such as CagA.

The initial diagnosis is made by biopsy of suspicious lesions on esophagogastroduodenoscopy (EGD, upper endoscopy). Simultaneous tests for "H. pylori" are also done to detect the presence of this microbe.

In other sites, chronic immune stimulation is also suspected in the pathogenesis (e.g. association between chronic autoimmune diseases such as Sjögren's syndrome and Hashimoto's thyroiditis, and MALT lymphoma of the salivary gland and the thyroid).

In order to diagnose MALT, a biopsy is needed from the affected tissue. If the abnormal tissue is suspected to be in the stomach or bowel, an endoscopy is done in order to get the biopsy. This requires either a gastroscopy or colonoscopy. If the lymphoma is thought to have spread to other areas in this region, an ultrasound scan is often done at the same time. If the abnormal tissue is thought to be in the lungs, a bronchoscopy is ordered.

In order to determine the correct type of lymphoma and stage it accurately, the physician will also need to do a physical exam, blood tests to determine blood cell counts, a CT scan, an MRI and/or a PET scan. A PET scan is the most important in planning a course of treatment.

A bone marrow biopsy may be ordered to test for lymph node involvement. If the lymphoma is in the stomach, the physician will test for H.pylori infection through a stool sample. This infection would be necessary to treat in conjunction to treating the cancer.

Due to the causal relationship between "H. pylori" infection and MALT lymphoma, identification of the infection is mandatory. Histological examination of GI biopsies yields a sensitivity of 95% with five biopsies, but these should be from sites uninvolved by lymphoma and the identification of the organism may be compromised by areas of extensive intestinal metaplasia. As proton-pump inhibition can suppress infection, any treatment with this class of drug should be ceased 2 weeks prior to biopsy retrieval. Serology should be performed if histology is negative, to detect suppressed or recently treated infections. Following the recognition of the association of gastric MALT lymphoma with "H. pylori" infection, it was established that early-stage gastric disease could be cured by "H. pylori" eradication, which is now the mainstay of therapy. Fifty to 95% of cases achieve complete response (CR) with "H. pylori" treatment.

A t(11;18)(q21;q21) chromosomal translocation, giving rise to an "API2-MLT" fusion gene, is predictive of poor response to eradication therapy.

The Gold standard for all Urinary incontinence is an urodynamic study that looks for bladder capacity, detrusor stability, contractility and voiding ability (Cystometry)

Prognoses and treatments are different for HL and between all the different forms of NHL, and also depend on the grade of tumour, referring to how quickly a cancer replicates. Paradoxically, high-grade lymphomas are more readily treated and have better prognoses: Burkitt lymphoma, for example, is a high-grade tumour known to double within days, and is highly responsive to treatment. Lymphomas may be curable if detected in early stages with modern treatment.

Diagnosis usually occurs at an early stage of disease progression.

Bladder tamponade is obstruction of the bladder outlet due to heavy blood clot formation within it. It generally requires surgery. Such heavy bleeding is usually due to bladder cancer.

Many people with OAB symptoms had those symptoms subside within a year, with estimates as high as 39%, but most have symptoms for several years.

Diagnosis of OAB is made primarily on the person's signs and symptoms and by ruling out other possible causes such as an infection. Urodynamics, a bladder scope, and ultrasound are generally not needed. Additionally, urine culture may be done to rule out infection. The frequency/volume chart may be maintained and cystourethroscopy may be done to exclude tumor and kidney stones. If there is an underlying metabolic or pathologic condition that explains the symptoms, the symptoms may be considered part of that disease and not OAB.

OAB causes similar symptoms to some other conditions such as urinary tract infection (UTI), bladder cancer, and benign prostatic hyperplasia (BPH). Urinary tract infections often involve pain and hematuria (blood in the urine) which are typically absent in OAB. Bladder cancer usually includes hematuria and can include pain, both not associated with OAB, and the common symptoms of OAB (urgency, frequency, and nocturia) may be absent. BPH frequently includes symptoms at the time of voiding as well as sometimes including pain or hematuria, and all of these are not usually present in OAB. Diabetes insipidus, which causes high frequency and volume, though not necessarily urgency.

Lymphoma Association (UK)

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