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.

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.

Ureteral duplication is either:

- Partial - i.e. the two ureters drain into the bladder via a single common ureter. Partial, or incomplete, ureteral duplication is rarely clinically significant.

- Complete - in which the two ureters drain separately. Complete ureteral duplication may result in one ureter opening normally into the bladder, and the other being ectopic, ending in the vagina, the urethra or the vulval vestibule. These cases occur when the ureteric bud arises twice (rather than splitting).

A ureterocele is a congenital abnormality found in the ureter. In this condition the distal ureter balloons at its opening into the bladder, forming a sac-like pouch. It is most often associated with a duplicated collection system, where two ureters drain their respective kidney instead of one. Simple ureterocele, where the condition involves only a single ureter, represents only twenty percent of cases. Ureterocele affects one in 4,000 individuals, at least four-fifths of whom are female. Patients are frequently Caucasian.

Since the advent of the ultrasound, most ureteroceles are diagnosed prenatally. The pediatric and adult conditions are often found incidentally, i.e. through diagnostic imaging performed for unrelated reasons.

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.

A Gartner's duct cyst (sometimes incorrectly referred to as "vaginal inclusion cyst") is a benign vaginal cystic lesion that arises from the Gartner's duct, which is a vestigial remnant of the mesonephric duct (wolffian duct) in females. They are typically small asymptomatic cysts that occur along the lateral walls of the vagina, following the course of the duct. They can present in adolescence with painful menstruation (Dysmenorrhea) or difficulty inserting a tampon. They can also enlarge to substantial proportions and be mistaken for urethral diverticulum or other structures.

There is a small association between Gartner's duct cysts and metanephric urinary anomalies, such as ectopic ureter & ipsilateral renal hypoplasia. Because of this, imaging is recommended before excision.

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.

Vesicoureteral reflux (VUR), also known as vesicoureteric reflux, is a condition in which urine flows retrograde, or backward, from the bladder into the ureters/kidneys. Urine normally travels in one direction (forward, or anterograde) from the kidneys to the bladder via the ureters, with a 1-way valve at the vesicoureteral (ureteral-bladder) junction preventing backflow. The valve is formed by oblique tunneling of the distal ureter through the wall of the bladder, creating a short length of ureter (1–2 cm) that can be compressed as the bladder fills. Reflux occurs if the ureter enters the bladder without sufficient tunneling, i.e., too "end-on".

Megaureter is a medical anomaly whereby the ureter is abnormally . Congenital megaureter is an uncommon condition which is more common in males, may be bilateral, and is often associated with other congenital anomalies. The cause is thought to be aperistalsis of the distal ureter, leading to dilatation.

The cutoff value for megaureter is when it is wider than 6 or 7 mm.

A functional obstruction at the lower end of the ureter leads to progressive dilatation and a tendency to infection. The ureteric orifice appears normal and a ureteric catheter passes easily.

Definitive surgical treatment involves refashioning the lower end of the affected ureter so that a tunnelled reimplantation into the bladder can be done to prevent reflux.

The signs and symptoms of hydronephrosis depend upon whether the obstruction is acute or chronic, partial or complete, unilateral or bilateral. Hydronephrosis that occurs acutely with sudden onset (as caused by a kidney stone) can cause intense pain in the flank area (between the hips and ribs). Historically, this type of pain has been described as "Dietl's crisis". Conversely, hydronephrosis that develops gradually will generally cause either attacks of a dull discomfort or no pain. Nausea and vomiting may also occur. An obstruction that occurs at the urethra or bladder outlet can cause pain and pressure resulting from distension of the bladder. Blocking the flow of urine will commonly result in urinary tract infections which can lead to the development of additional stones, fever, and blood or pus in the urine. If complete obstruction occurs, kidney failure may follow.

Blood tests may show impaired kidney function (elevated urea or creatinine) or electrolyte imbalances such as hyponatremia or hyperchloremic metabolic acidosis. Urinalysis may indicate an elevated pH due to the secondary destruction of nephrons within the affected kidney. Physical examination may detect a palpable abdominal or flank mass caused by the enlarged kidney.

A urerovaginal fistula is a result of trauma, infection, pelvic surgery, radiation treatment and therapy, malignancy, or inflammatory bowel disease. Symptoms can be troubling for women especially since some clinicians delay treatment until inflammation is reduced and stronger tissue has formed. The fistula may develop as a maternal birth injury from a long and protracted labor, long dilation time and expulsion period. Difficult deliveries can create pressure necrosis in the tissue that is being pushed between the head of the infant and the softer tissues of the vagina, ureters, and bladder.

Radiographic imaging can assist clinicians in identifying the abnormality. A Ureterovaginal fistula is always indicative of an obstructed kidney necessitating emergency intervention followed later by an elective surgical repair of the fistula.

A ureterovaginal fistula is an abnormal passageway existing between the ureter and the vagina. It presents as urinary incontinence. Its impact on women is to reduce the "quality of life dramatically."

Hydronephrosis—literally "water inside the kidney"—refers to distension and dilation of the renal pelvis and calyces, usually caused by urinary retention due to obstruction of the free flow of urine from the kidney. Untreated, it leads to progressive atrophy of the kidney. One or both kidneys may be affected. In cases of hydroureteronephrosis, there is distention of both the ureter and the renal pelvis and calices.

Obstructive uropathy is a structural or functional hindrance of normal urine flow, sometimes leading to renal dysfunction (obstructive nephropathy).

It is a very broad term, and does not imply a location or cause.

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.

Symptoms, less likely in chronic obstruction, are pain radiating to the T11 to T12 dermatomes, anuria, nocturia, or polyuria.

In medicine, ovarian vein syndrome is a rare (possibly not uncommon, certainly under-diagnosed) condition in which a dilated ovarian vein compresses the ureter (the tube that brings the urine from the kidney to the bladder). This causes chronic or colicky abdominal pain, back pain and/or pelvic pain. The pain can worsen on lying down or between ovulation and menstruation. There can also be an increased tendency towards urinary tract infection or pyelonephritis (kidney infection). The right ovarian vein is most commonly involved, although the disease can be left-sided or affect both sides. It is currently classified as a form of pelvic congestion syndrome.

A preureteric vena cava, also known as a retrocaval ureter, is a rare congenital malformation of the right human ureter, in which the ureter passes behind the inferior vena cava, causing compression possibly leading to hydronephrosis. The prevalence of this condition is approximately 1 per 1,000 persons, with males 2-3 times more likely than females to develop the condition. Symptoms often do not manifest until those with the condition are aged in their 20s or 30s.

Symptoms vary between individuals and can be dependent upon the stage of growth of the carcinoma. Presence of the carcinoma can lead to be asymptomatic blood in the urine (hematuria), Hematuria can be visible or detected microscopically. Visible hematuria is when urine appears red or brown and can be seen with the naked eye. Other symptoms are not specific. Other inflammatory conditions that affect the bladder and kidney can create similar symptoms. Early detection facilitates curing the disease. Other symptoms can involve:

- pain or burning on urination

- the sensation of not being able to completely empty the bladder

- the sensation of needing to urinate more often or more frequently than normal

These symptoms are general and also indicate less serious problems.

In patients with this condition, the central portion of the kidney may be found just inferior to the inferior mesenteric artery because the normal embryologic ascent of the kidneys is arrested by its presence in people with central fusion of the kidneys. Horseshoe kidney is often asymptomatic, though persons affected by this condition may experience nausea, abdominal discomfort, kidney stones and urinary tract infections at greater frequency than those without renal fusion. There is currently no treatment for renal fusion other than symptomatic treatment.

Imaging Findings -

The 2 kidneys on opposite sides of the body with the lower poles fused in midline. Midline or symmetrical fusion (90% of cases).

May be missed on US, therefore pay careful attention to identification of lower poles of kidneys.

Renal long axis medially orientated,

Lower poles with curved configuration, elongation and poorly defined

Isthmus crosses midline anterior to spine and great vessels.

US for diagnosis in utero

IVP followed by CT or scintigraphy for pre-operative assessment

Variant arterial supply -

Bilateral renal arteries,

Inferior mesenteric Artery,

Arteries arising from aorta or common iliac, internal iliac, external iliac or inferior mesenteric arteries.

The lower poles of these kidneys fuse in the midline anterior to the aorta and spine. The isthmus is usually located at L4/5 level between the aorta and IMA.

Nuclear medicine (DMSA) scan confirms horseshoe kidney with fusion of both renal lower poles.

Renal colic is a type of abdominal pain commonly caused by kidney stones.

An inverted papilloma is a type of tumor in which surface epithelial cells grow downward into the underlying supportive tissue. It may occur in the nose and/or sinuses or in the urinary tract (bladder, renal pelvis, ureter, urethra). When it occurs in the nose or sinuses, it may cause symptoms similar to those caused by sinusitis, such as nasal congestion. When it occurs in the urinary tract, it may cause blood in the urine.

Renal colic typically begins in the flank and often radiates to the hypochondrium (the part of the anterior abdominal wall below the costal margins) or the groin. It is typically colicky (comes in waves) due to ureteric peristalsis, but may be constant. It is often described as one of the strongest pain sensations known.

Although this condition can be very painful, kidney stones usually cause no permanent physical damage. The experience is said to be traumatizing due to pain, and the experience of passing blood, blood clots, and pieces of the stone. Depending on the sufferer's situation, nothing more than drinking significant amounts of water may be called for; in other instances, surgery may be needed. Preventive treatment can be instituted to minimize the likelihood of recurrence.

Dipygus manifests as duplicated lower limbs and could include additional organs or bodily structures.

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