It has been estimated that VUR is present in more than 10% of the population. Younger children are more prone to VUR because of the relative shortness of the submucosal ureters. This susceptibility decreases with age as the length of the ureters increases as the children grow. In children under the age of 1 year with a urinary tract infection, 70% will have VUR. This number decreases to 15% by the age of 12. Although VUR is more common in males antenatally, in later life there is a definite female preponderance with 85% of cases being female.

Smoking is the number one cause of Reinke's edema. Other factors include gastroesophageal reflux, hypothyroidism and chronic overuse of the voice. Smoking is the only risk factor that may lead to cancer. Additionally, the combination of several risk factors increase the likelihood of an individual developing Reinke's edema. For example, an individual who smokes and also has gastric reflux would have an increased susceptibility for developing Reinke's edema over time.

Reinke's edema is commonly diagnosed in middle-aged females with a history of smoking (aged 50 years or older). Because males have lower pitched voices than females, males are less likely to observe a significant changes in the voice, and are therefore less likely to seek treatment. Females also report more physical discomfort due to Reinke's edema. The risk of Reinke's edema increases with age and also with prolonged exposure to smoking. Additionally, individuals in professions that require constant use of the voice, such as singers, teachers, and radio hosts, may be at an increased risk for developing the disease.

Because the disease is heavily linked to smoking, there is no established way to screen for Reinke's edema. Similarly, the only way to prevent Reinke's edema is to avoid smoking. By adopting a non-smoking lifestyle after being diagnosed with Reinke's edema, it is possible to stop the disease's progression, although it is not possible to reverse it. Therefore, it is critical to maintain a non-smoking lifestyle even after surgery, because the fluid can re-emerge. In fact, in many cases surgeons will not perform surgery without the guarantee that the individual will stop smoking.

Occurring at a rate between 1 in 10,000 to 1 in 50,000 with a male-to-female ratio of 2.3-6:1, bladder exstrophy is relatively rare. For those individuals with bladder exstrophy who maintain their ability to reproduce, the risk of bladder exstrophy in their children is approximately 500-fold greater than the general population.

The American Urological Association recommends ongoing monitoring of children with VUR until the abnormality resolves or is no longer clinically significant. The recommendations are for annual evaluation of blood pressure, height, weight, analysis of the urine, and kidney ultrasound.

Hand-foot-genital syndrome is inherited in an autosomal dominant manner. The proportion of cases caused by de novo mutations is unknown because of the small number of individuals described. If a parent of the proband is affected, the risk to the siblings is 50%. When the parents are clinically unaffected, the risk to the sibs of a proband appears to be low. Each child of an individual with HFGS has a 50% chance of inheriting the mutation. Prenatal testing may be available through laboratories offering custom prenatal testing for families in which the disease-causing mutation has been identified in an affected family member.

Granulomatous disease, including sarcoidosis, granulomatosis with polyangiitis, and midline granuloma, may also lead to NLD obstruction.

Duplicated ureter is the most common renal abnormality, occurring in approximately 1% of the population.

Race: Duplicated ureter is more common in Caucasians than in African-Americans.

Sex: Duplicated ureter is more common in females. However, this may be due to the higher frequency of urinary tract infections in females, leading to a higher rate of diagnosis of duplicated ureter.

Involutional stenosis is probably the most common cause of NLD obstruction in older persons. It affects women twice as frequently as men. Although the inciting event in this process is unknown, clinicopathologic study suggests that compression of the lumen of the NLD is caused by inflammatory infiltrates and edema. This may be the result of an unidentified infection or possibly an autoimmune disease.

The female homolog to the male verumontanum from which the valves originate is the hymen.

The cause of multicystic dysplastic kidney can be attributed to genetics. Renal dysplasia can be a consequence of a genetic syndrome, which in turn may affect the digestive tract, nervous system, or other areas of the urinary tract. If the mother had been taking certain prescription drugs such as those for hypertension, this may be a precipitating factor as well.

Ask-Upmark kidneys are a cause of secondary hypertension that can be curable.

While most cases of horseshoe kidneys are asymptomatic and discovered upon autopsy, the condition may increase the risk for:

- Kidney obstruction – abnormal placement of ureter may lead to obstruction and dilation of the kidney.

- Kidney infections – associated with vesicoureteral reflux.

- Kidney stones – deviant orientation of kidneys combined with slow urine flow and kidney obstruction may lead to kidney stones.

- Kidney cancer – increased risk of renal cancer, especially Wilms' tumor, transitional cell carcinoma, and an occasional case report of carcinoid tumor. Despite increased risk, the overall risk is still relatively low.

The prevalence of horseshoe kidneys in females with Turner Syndrome is about 15%.

It can be associated with trisomy 18.

It can be associated with venous anomalies like left sided IVC 9.

In regard to the epidemiology of multicystic dysplasia kidney, the incidence of MCDK is estimated to be 1 in every 4,000 live births, making it rare in terms of the general population.

There is a genetic predisposition, first-degree relatives have a great increase in the chance of VUR. The gene frequency is estimated to be 1:600. The American Academy of Pediatrics recommends that children from 2 to 24 months presenting with a UTI should be investigated for VUR.

For patients in need of tracheal intubation to receive oral drugs, an oversized tube, excessive movement of the tube, or infection can lead to contact granulomas, but this is rare.

Diagnosis is based on physical examination including radiographs of the hands and feet and imaging studies of the kidneys, bladder, and female reproductive tract. HOXA13 is the only gene known to be associated with HFGS. Approximately 60% of mutations are polyalanine expansions. Molecular genetic testing is clinically available.

Inflammatory issues associated with contact granuloma include gastroesophageal reflux, allergy or infection. There is some disagreement among researchers as to whether inflammatory issues are a direct cause. Some researchers identify reflux and infection as indirect causes due to aggressive coughing that usually occurs as a result.

The most important criterion for improving long-term prognosis is success of the initial closure. If a patient requires more than one closure their chance of continence drops off precipitously with each additional closure - at just two closures the chance of voiding continence is just 17%.

Even with successful surgery, people may have long-term complications. Some of the most common include:

- Vesicoureteral reflux

- Bladder spasm

- Bladder calculus

- Urinary tract infections

It is thought to be congenital or the consequence of vesicoureteral reflux.

The frequency is unknown, but the disease is considered to be very rare.

The causes of diseases of the body are common to the urinary tract. Structural and or traumatic change can lead to hemorrhage, functional blockage or inflammation. Colonisation by bacteria, protozoa or fungi can cause infection. Uncontrolled cell growth can cause neoplasia.

For example:

- Urinary tract infections (UTIs), interstitial cystitis

- incontinence (involuntary loss of urine), benign prostatic hyperplasia (where the prostate overgrows), prostatitis (inflammation of the prostate).

- Urinary retention, which is a common complication of benign prostatic hyperplasia (BPH), though it can also be caused by other types of urinary tract obstruction, nerve dysfunction, tethered spinal cord syndrome, constipation, infection and certain medications.

- Transitional cell carcinoma (bladder cancer), renal cell carcinoma (kidney cancer), and prostate cancer are examples of neoplasms affecting the urinary system.

- Urinary tract obstruction

The term "uropathy" refers to a disease of the urinary tract, while "nephropathy" refers to a disease of the kidney.

Horseshoe kidney, also known as "ren arcuatus" (in Latin), renal fusion or super kidney, is a congenital disorder affecting about 1 in 600 people, more common in men.

In this disorder, the patient's kidneys fuse together to form a horseshoe-shape during development in the womb. The fused part is the isthmus of the horseshoe kidney.

Fusion abnormalities of the kidney can be categorized into two groups: horseshoe kidney and crossed fused ectopia. The 'horseshoe kidney' is the most common renal fusion anomaly.

The following increase an individual's chances for acquiring VCD:

- Upper airway inflammation (allergic or non-allergic rhinitis, chronic sinusitis, recurrent upper respiratory infections)

- Gastroesophageal reflux disease

- Past traumatic event that involved breathing (e.g. near-drowning, suffocation)

- Severe emotional trauma or distress

- Female gender

- Playing a wind instrument

- Playing a competitive or elite sport

Without diagnostic evaluation, the cause of UAB is unclear, as there are multiple possible causes. UAB symptoms can accurately reflect impaired bladder emptying due either to DU or obstruction (normal or large storage volumes, elevated post-void residual volume), or can result from a sense of incomplete emptying of a hypersensitive bladder (small storage volumes, normal or elevated postvoid residual volume). UAB potentially might also result from inaccurate perceptions of bladder function, such as in neurologic or psychiatric disease. DU itself is often linked to a weak detrusor muscle (impaired contractility), however this association is weak. Both UAB and DU have been associated with diminished sensitivity to bladder volumes rather than objective detrusor weakness, suggesting both symptoms (UAB) and function (DU) have a significant component of sensory dysfunction, leading to impaired bladder sensations and control (Smith et al., 2015).

The underlying contributors to UAB include neurologic disease, metabolic disease (e.g. diabetes), chronic bladder outlet obstruction (e.g. obstructive BPH or complications of anterior vaginal surgery), cognitive decline (such as with aging), psychiatric disorders, and adverse effects of medications. Additionally, structural abnormalities expanding the urinary reservoir beyond the bladder, such as massive vesicoureteral reflux or large bladder diverticulae, can result in UAB. While aging itself is often associated with UAB (and DU), there is scant evidence to support this claim.

Posterior urethral valve (PUV) disorder is an obstructive developmental anomaly in the urethra and genitourinary system of male newborns. A posterior urethral valve is an obstructing membrane in the posterior male urethra as a result of abnormal "in utero" development. It is the most common cause of bladder outlet obstruction in male newborns. The disorder varies in degree, with mild cases presenting late due to milder symptoms. More severe cases can have renal and respiratory failure from lung underdevelopment as result of low amniotic fluid volumes, requiring intensive care and close monitoring. It occurs in about one in 8000 babies.