Lower urinary tract infection is also referred to as a bladder infection. The most common symptoms are burning with urination and having to urinate frequently (or an urge to urinate) in the absence of vaginal discharge and significant pain. These symptoms may vary from mild to severe and in healthy women last an average of six days. Some pain above the pubic bone or in the lower back may be present. People experiencing an upper urinary tract infection, or pyelonephritis, may experience flank pain, fever, or nausea and vomiting in addition to the classic symptoms of a lower urinary tract infection. Rarely the urine may appear bloody or contain visible pus in the urine.

In young children, the only symptom of a urinary tract infection (UTI) may be a fever. Because of the lack of more obvious symptoms, when females under the age of two or uncircumcised males less than a year exhibit a fever, a culture of the urine is recommended by many medical associations. Infants may feed poorly, vomit, sleep more, or show signs of jaundice. In older children, new onset urinary incontinence (loss of bladder control) may occur.

Signs and symptoms of emphysematous cystitis include air in the bladder wall, altered mental status, severe abdominal pain, weakness, dark urine, dysuria, fever, lethargy, vomiting, as well as white blood cells and bacteria in the urine (Mccabe). Where some patients may be asymptomatic, others may present with septic shock (De Baets, Baert). Symptoms can vary greatly from patient to patient, which makes the disease difficult to diagnose. In some cases of emphysematous cystitis, patients do not even claim to have any urinary symptoms (Mokabberi). Urinary symptoms can include blood in the urine, increased urinary frequency, urgency, occasional incontinence, difficulty voiding, and burning sensation. Emphysematous cystitis is often indicated in patients who have air in the urine (Bobba). In some cases, emphysematous cystitis can cause thickening of the bladder wall (Weerakkody). Clinical subcutaneous emphysema is a rare complication of emphysematous cystitis that has a poor prognosis (Ahmed-Ramadan, Blake).

Symptomatic bacteriuria is bacteriuria with the accompanying symptoms of a urinary tract infection (such as frequent urination, painful urination, fever, back pain). Symptomatic bacteriuria can be indicative of a urinary tract infection like pyelonephritis or cystitis. The most common type of bacteriuria associated with urinary tract infections is "Escherichia coli" which is a gram-negative rod-shaped bacteria.

Asymptomatic bacteriuria is bacteriuria without accompanying symptoms of a urinary tract infection. It is more common in women, in the elderly, in residents of long-term care facilities, and in people with diabetes, bladder catheters and spinal cord injuries. People with a long-term Foley catheter uniformly show bacteriuria. Chronic asymptomatic bacteriuria without urinary tract infection symptoms occurs in as many as 50% of the population in long-term care.

In pregnant women bacteriuria is associated with low birth weight, preterm delivery, and infection of the newborn. Bacteriuria in pregnancy also increase the risk of preeclampsia.

Emphysematous cystitis is a rare type of infection of the bladder wall by gas-forming bacteria or fungi. The most frequent offending organism is "E. coli". Other gram negative bacteria, including "Klebsiella" and "Proteus" are also commonly isolated. Fungi, such as "Candida", have also been reported as causative organisms. "Citrobacter" and "Enterococci" have also been found to cause Emphysematous cystitis (Mokabberi). Although it is a rare type of bladder infection, it is the most common type of all gas-forming bladder infections (Mccabe). The condition is characterized by the formation of air bubbles in and around the bladder wall. The gas found in the bladder consists of nitrogen, hydrogen, oxygen, and carbon dioxide. The disease most commonly affects elderly diabetic and immunocompromised patients (Sereno). The first case was identified in a post-mortem examination in 1888 (Nemati, Basra).

Signs and symptoms of acute pyelonephritis generally develop rapidly over a few hours or a day. It can cause high fever, pain on passing urine, and abdominal pain that radiates along the flank towards the back. There is often associated vomiting.

Chronic pyelonephritis causes persistent flank or abdominal pain, signs of infection (fever, unintentional weight loss, malaise, decreased appetite), lower urinary tract symptoms and blood in the urine. Chronic pyelonephritis can in addition cause fever of unknown origin. Furthermore, inflammation-related proteins can accumulate in organs and cause the condition AA amyloidosis.

Physical examination may reveal fever and tenderness at the costovertebral angle on the affected side.

Pyelonephritis that has progressed to urosepsis may be accompanied by signs of septic shock, including rapid breathing, decreased blood pressure, shivering, and occasionally delirium.

Men with acute prostatitis often have chills, fever, pain in the lower back, perineum, or genital area, urinary frequency and urgency often at night, burning or painful urination, body aches, and a demonstrable infection of the urinary tract, as evidenced by white blood cells and bacteria in the urine. Acute prostatitis may be a complication of prostate biopsy. Often, the prostate gland is very tender to palpation through the rectum.

Signs indicative of urethral syndrome include a history of chronic recurrent urinary tract infections (UTI) in the absence of both conventional bacterial growth and pyuria (more than 5 white blood cells per High Power Field). Episodes are often related to sexual intercourse.

Some physicians believe that urethral syndrome may be due to a low grade infection of the Skene's glands on the sides and bottom of the urethra. The Skene's glands are embryologically related to the prostate gland in the male, thus urethral syndrome may share a comparable cause with chronic prostatitis.

Possible non-infective causes include hormonal imbalance, trauma, allergies, anatomical features such as diverticula, and post-surgical scarring and adhesions.

The symptoms of a cystocele may include:

- a vaginal bulge

- the feeling that something is falling out of the vagina

- the sensation of pelvic heaviness or fullness

- difficulty starting a urine stream

- a feeling of incomplete urination

- frequent or urgent urination

- fecal incontinence

- frequent urinary tract infections

A bladder that has dropped from its normal position and into the vagina can cause some forms of incontinence and incomplete emptying of the bladder.

Pyelonephritis is inflammation of the kidney, typically due to a bacterial infection. Symptoms most often include fever and flank tenderness. Other symptoms may include nausea, burning with urination, and frequent urination. Complications may include pus around the kidney, sepsis, or kidney failure.

It is typically due to a bacterial infection, most commonly "Escherichia coli". Risk factors include sexual intercourse, prior urinary tract infections, diabetes, structural problems of the urinary tract, and spermicide use. The mechanism of infection is usually spread up the urinary tract. Less often infection occurs through the bloodstream. Diagnosis is typically based on symptoms and supported by urinalysis. If there is no improvement with treatment, medical imaging may be recommended.

Pyelonephritis may be preventable by urination after sex and drinking sufficient fluids. Once present it is generally treatment with antibiotic, such as ciprofloxacin or ceftriaxone. Those with severe disease may required treatment in hospital. In those with certain structural problems of the urinary tract or kidney stones, surgery may be required.

Pyelonephritis is common. About 1 to 2 per 1,000 women are affected a year and just under 0.5 per 1,000 males. Young adult females are most often affected, followed by the very young and old. With treatment, outcomes are generally good in young adults. Among people over the age of 65 the risk of death is about 40%.

Chronic bacterial prostatitis is a relatively rare condition that usually presents with an intermittent UTI-type picture. It is defined as recurrent urinary tract infections in men originating from a chronic infection in the prostate. Symptoms may be completely absent until there is also bladder infection, and the most troublesome problem is usually recurrent cystitis.

Chronic bacterial prostatitis occurs in less than 5% of patients with prostate-related non-BPH lower urinary tract symptoms (LUTS).

Dr. Weidner, Professor of Medicine, Department of Urology, University of Gießen, has stated: "In studies of 656 men, we seldom found chronic bacterial prostatitis. It is truly a rare disease. Most of those were E-coli."

Acute prostatitis is relatively easy to diagnose due to its symptoms that suggest infection. The organism may be found in blood or urine, and sometimes in both. Common bacteria are "Escherichia coli, Klebsiella, Proteus, Pseudomonas, Enterobacter, Enterococcus, Serratia," and "Staphylococcus aureus." This can be a medical emergency in some patients and hospitalization with intravenous antibiotics may be required. A complete blood count reveals increased white blood cells. Sepsis from prostatitis is very rare, but may occur in immunocompromised patients; high fever and malaise generally prompt blood cultures, which are often positive in sepsis. A prostate massage should never be done in a patient with suspected acute prostatitis, since it may induce sepsis. Since bacteria causing the prostatitis is easily recoverable from the urine, prostate massage is not required to make the diagnosis. Rectal palpation usually reveals an enlarged, exquisitely tender, swollen prostate gland, which is firm, warm, and, occasionally, irregular to the touch. C-reactive protein is elevated in most cases.

Prostate biopsies are not indicated as the (clinical) features (described above) are diagnostic. The histologic correlate of acute prostatitis is a neutrophilic infiltration of the prostate gland.

Acute prostatitis is associated with a transiently elevated PSA, i.e., the PSA is increased during an episode of acute prostatitis and then decreases again after it has resolved. PSA testing is not indicated in the context of uncomplicated acute prostatitis.

The hallmark sign of urethral stricture is a weak urinary stream. Other symptoms include:

- Splaying of the urinary stream

- Urinary frequency

- Urinary urgency

- Straining to urinate

- Pain during urination

- Urinary tract infection

- Prostatitis

- Inability to completely empty the bladder.

Some patients with severe urethral strictures are completely unable to urinate. This is referred to as acute urinary retention, and is a medical emergency. Hydronephrosis and renal failure may also occur.

A cystocele, also known as a prolapsed bladder, is a medical condition in which a woman's bladder bulges into her vagina. Some may have no symptoms. Other may have trouble starting urination, urinary incontinence, or frequent urination. Complications may include recurrent urinary tract infections and urinary retention. Cystocele and a prolapsed urethra often occur together and is called a cystourethrocele. Cycstocele can negatively affect quality of life.

Causes include childbirth, constipation, chronic cough, heavy lifting, hysterectomy, genetics, and being overweight. The underlying mechanism involves weakening of muscles and connective tissue between the bladder and vagina. Diagnosis is often based on symptoms and examination.

If the cystocele causes few symptoms, avoiding heavy lifting or straining may be all that is recommended. In those with more significant symptoms a vaginal pessary, pelvic muscle exercises, or surgery may be recommended. The type of surgery typically done is known as a colporrhaphy. The condition becomes more common with age. About a third of women over the age of 50 are affected to some degree.

Urethral syndrome is characterised by a set of symptoms typically associated with lower urinary tract infection, such as painful urination (dysuria) and frequency. It is a diagnosis of exclusion, made when there is no significant presence of bacteriuria with a conventional pathogen ruling out urinary tract infection, and when cystoscopy shows no inflammation of the bladder, ruling out interstitial cystitis and cystitis cystica. In women, vaginitus should also be ruled out.

Ectopic ureter (or ureteral ectopia) is a medical condition where the ureter, rather than terminating at the urinary bladder, terminates at a different site. In males this site is usually the urethra, in females this is usually the urethra or vagina. It can be associated with renal dysplasia, frequent urinary tract infections, and urinary incontinence (usually continuous drip incontinence). Ectopic ureters are found in 1 of every 2000–4000 patients, and can be difficult to diagnose, but are most often seen on CT scans.

Ectopic ureter is commonly a result of a duplicated renal collecting system, a duplex kidney with 2 ureters. In this case, usually one ureter drains correctly to the bladder, with the duplicated ureter presenting as ectopic.

Most children with vesicoureteral reflux are asymptomatic. Vesicoureteral reflux may be diagnosed as a result of further evaluation of dilation of the kidney or ureters draining urine from the kidney while in utero as well as when a sibling has VUR (though routine testing in either circumstance is controversial). Reflux also increases risk of acute bladder and kidney infections, so testing for reflux may be performed after a child has one or more infections.

In infants, the signs and symptoms of a urinary tract infection may include only fever and lethargy, with poor appetite and sometimes foul-smelling urine, while older children typically present with discomfort or pain with urination and frequent urination.

The younger the patient and the lower the grade at presentation the higher the chance of spontaneous resolution. Approximately 85% of grade I & II VUR cases will resolve spontaneously. Approximately 50% of grade III cases and a lower percentage of higher grades will also resolve spontaneously.

Urethral strictures most commonly result from injury, urethral instrumentation, infection, non-infectious inflammatory conditions of the urethra, and after prior hypospadias surgery. Less common causes include congenital urethral strictures and those resulting from malignancy.

Urethral strictures after blunt trauma can generally be divided into two sub-types;

- Pelvic fracture-associated urethral disruption occurs in as many as 15% of severe pelvic fractures. These injuries are typically managed with suprapubic tube placement and delayed urethroplasty 3 months later. Early endoscopic realignment may be used in select cases instead of a suprapubic tube, but these patients should be monitored closely as vast majority of them will require urethroplasty.

- Blunt trauma to the perineum compresses the bulbar urethra against the pubic symphysis, causing a "crush" injury. These patients are typically treated with suprapubic tube and delayed urethroplasty.

Other specific causes of urethral stricture include:

- Instrumentation (e.g., after transurethral resection of prostate, transurethral resection of bladder tumor, or endoscopic kidney surgery)

- Infection (typically with Gonorrhea)

- Lichen sclerosus

- Surgery to address hypospadias can result in a delayed urethral stricture, even decades after the original surgery.

Prenatally diagnosed hydronephrosis (fluid-filled kidneys) suggest post-natal follow-up examination.

The strongest neo-natal presentation is urinary tract infection. A hydronephrotic kidney may present as a palpable abdominal mass in the newborn, and may suggest an ectopic ureter or ureterocele.

In older children, ureteral duplication may present as:

- Urinary tract infection - most commonly due to vesicoureteral reflux (flow of urine from the bladder into the ureter, rather than vice versa).

- Urinary incontinence in females occurs in cases of ectopic ureter entering the vagina, urethra or vestibule.

Causes of urinary tract obstruction include:

- Bladder stone and renal stone

- Benign prostatic hyperplasia

- Obstruction as a congenital disorder.

The signs and symptoms of ureterocele in the latter two forms can easily be confused with other medical conditions. Symptoms can include:

- Frequent urinary tract infections

- Pyelonephritis

- Obstructive voiding symptoms

- Urinary retention

- Failure to thrive

- Hematuria

- Cyclic abdominal pain

- Urolithiasis

- Cobra head sign is seen in radiography

- In females: salpingitis, hydrosalpinx with sepsis or torsion. T.O. mass.

Duplicated ureter or Duplex Collecting System is a congenital condition in which the ureteric bud, the embryological origin of the ureter, splits (or arises twice), resulting in two ureters draining a single kidney. It is the most common renal abnormality, occurring in approximately 1% of the population. The additional ureter may result in a ureterocele, or an ectopic ureter.

A prostatic stent is a stent used to keep open the male urethra and allow the passing of urine in cases of prostatic obstruction and lower urinary tract symptoms (LUTS). Prostatic obstruction is a common condition with a variety of causes. Benign prostatic hyperplasia (BPH) is the most common cause, but obstruction may also occur acutely after treatment for BPH such as transurethral needle ablation of the prostate (TUNA), transurethral resection of the prostate (TURP), transurethral microwave thermotherapy (TUMT), prostate cancer or after radiation therapy.